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Additives for Plastics Handbook

2nd Edition

This Page Intentionally Left Blank

Additives for Plastics Handbook 2nd Edition

John Murphy

ELSEVIER ADVANCED TECHNOLOGY

UK USA JAPAN

Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, UK Elsevier Science Inc, 360 Park Avenue South, New York, NY 10010, USA Elsevier Science Japan, Tsunashima Building Annex, 3-20-12 Yushima, Bunkyo-ku, Tokyo 113, Japan Copyright © 2001 Elsevier Science Ltd. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means: electronic, electrostatic, magnetic tape, mechanical, photocopying, recording or otherwise, without permission in writing from the publishers. First edition 1996 Second edition 2001 I S B N l 85617 370 4 Second impression 2003

No responsibility is assumed by the Publisher for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. Published by Elsevier Advanced Technology, The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, UK Tel: +44(0) 1865 843000 Fax:+44(0) 1865 843971 Typeset by Variorum Publishing Ltd, Rugby Printed and bound in Great Britain by Biddies Ltd, www.biddies,co.uk

CONTENTS List of Tables

xvii

List of Figures

xxi

Preface and Publishers' note

xxiii

Chapter 1

An Overview of Additives

1

Chapter 2

Types of Additive and the Main Technical Trends

5

2.1

2.2

2.3 2.4 2.5 Chapter 3

Chapter 4

Current Lines of Development 2.1.1 Fillers 2.1.2 Pigments 2.1.3 Plasticizers 2.1.4 Stabilizers 2.1.5 Flame retardants Special Additives 2.2.1 Antistatic and conductive additives 2.2.2 Food contact and medical additives 2.2.3 Clarifiers, nucleating agents, compatibilizers Multi-functional Formulations Masterbatches Dendritic Polymers

5 6 7 7 8 8 9 9 9 10 10 10 11

The World Market

13

3.1 3.2 3.3 3.4 3.5

13 15 15 16 16

World Consumption of Additives The Market for Masterbatch Overall Commercial Trends Growth of Specialist Compounders Regional Factors

Modifying Specific Properties: Mechanical Properties - Fillers

19

4.1

21 21 21 21 21

Effect of Fillers 4.1.1 Mechanical properties 4.1.2 Thermal properties 4.1.3 Moisture content 4.1.4 Reinforcement mechanism of

fillers

vi


4.2 4.3

4.4 4.5 4.6

Chapter 5

Factors for Compounding 4.2.1 Aggregation of fillers Types of Fillers 4.3.1 Calcium carbonate Kaolin 4.3.2 Magnesium hydroxide (talc) 4.3.3 4.3.4 WoUastonite Silica 4.3.5 Metal powders 4.3.6 Microspheres 4.3.7 Expandable microspheres 4.3.8 Cellulose fillers 4.3.9 Surface Modification Modification Particle geometry 4.4.1 4.4.2 Coating Nano-technology 4.5.1 Processing nano-composites Commercial Trends

22 23 24

24 26 26 27 27 28 28 29 30 30 30 31 32 32 35

Modifying Specific Properties: Mechanical Properties Reinforcements

5.1 5.2

5.3

5.4 5.5 5.6 5.7

5.8

Fibres: The Basic Properties Types of Reinforcing Fibre 5.2.1 Aramid fibres Carbon or graphite fibres 5.2.2 Glass fibre 5.2.3 5.2.3.1 E-CRglass 5.2.3.2 Other developments 5.2.3.3 Forms of glass fibre 5.2.3.4 Chopped/milled products 5.2.4 Polyester fibre Polyethylene fibre 5.2.5 Hybrid fibres 5.2.6 Other Fibres Asbestos fibre 5.3.1 Boron fibre 5.3.2 Nylon fibre 5.3.3 Natural Fibres Forms of Reinforcement Long-fibre Reinforcement New Developments Polyurethane/long fibres 5.7.1 ABS/long fibres 5.7.2 Shaped fibres 5.7.3 Commercial Trends

37

39 40 40 41 43 45 46 47 47 48 48 49 49 49 49 49 50 51 51 53 54 54 54 55

Contents Chapter 6

Modifying Specific Properties: Appearance - Colorants, Pigments, Dyes, Special Effects

6.1

6.2 6.3 6.4

6.5 6.6 6.7 6.8 6.9 6.10 6.11

6.12 Chapter 7

Main Types ofPigment and Colorant 6.1.1 Mixed metal oxides 6.1.2 Dyes 6.1.3 Liquid colours Addition of Colorants Replacement of Cadmium Pigments for Special Effects 6.4.1 Aluminium pigments 6.4.2 Pearlescents 6.4.3 Light interference pigments 6.4.4 Fluorescents 6.4.5 Thermochromic and photochromic pigments 6.4.5.1 Intelligent' heat protection for food products 6.4.5.2 High-performance dyes for CD manufacture 6.4.5.3 Solar heat Laser Marking Pigment Dispersants Multi-functional Systems Pigments for Engineering Plastics The Effect of Pigments on Dimensions Colorants for Food and Medicals Recent Developments 6.11.1 Colour strength 6.11.2 Weathering 6.11.3 Natural effects 6.11.4 New forms of pigment 6.11.5 Surface treatment 6.11.6 New pigment chemistry Market Trends

Modifying Specific Properties: Appearance - Black and White Pigmentation

7.1

Types of White Pigment 7.1.1 Titanium dioxide 7.1.1.1 Surface treatments 7.1.1.2 Titanium dioxide grades 7.1.1.3 Opacity and tinting strength 7.1.1.4 Colour 7.1.2 Zinc sulphide 7.1.3 Other white pigments and extenders 7.1.3.1 Aluminium silicates 7.1.3.2 Barium sulphate ('blanc fixe')

vii

57

58 58 58 59 60 61 62 63 63 63 64 64 65 65 65 66 66 67 67 68 69 69 69 69 70 70 70 70 71

73

73 73 74 76 76 78 78 80 80 80

viii


7.2

7.3 7.4 Chapter 8

7.1.3.3 Calcium silicate 7.1.3.4 Magnesium silicate 7.1.4 White masterbatch 7.1.5 New developments Black Pigments 7.2.1 Types of carbon black 7.2.1.1 Thermal oxidative decomposition processes 7.2.1.2 Thermal decomposition processes 7.2.1.3 Effect of particle size and structure on properties of carbon blacks 7.2.1.4 Testing for properties: structure effect and determination 7.2.2 Other black pigments 7.2.3 Black masterbatch 7.2.4 Recent developments Commercial Trends: Titanium Dioxide Commercial Trends: Carbon Black

85 86 86 87 89 90 91 92 92

Modifying Specific Properties: Resistance to Heat - Heat Stabilizers

8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8

8.9 8.10 Chapter 9

80 81 82 82 84 84

How They Work Antioxidants 8.2.1 Primary antioxidants 8.2.2 Secondary antioxidants Blends Replacement of Heavy Metals 8.4.1 Organotins Effect of Silica on the Activity of Stabilizers Benzoxazolone Derivatives for PVC New Chemistry for Stabilizers 8.7.1 Lactone chemistry 8.7.2 Vitamin E Recent Developments 8.8.1 Pipes and fittings 8.8.2 Foamed pipe 8.8.3 Cable insulation 8.8.4 Medical products Other Stabilizers Commercial Trends

Modifying Specific Properties: Resistance to Light - UV Stabilizers

9.1 9.2 9.3 9.4

How They Work UV Screening Pigments Absorbers Energy Transfer Agents/Quenchers

93

93 95 95 96 97 97 98 99 100 100 100 102 103 103 104 104 104 105 105 107

107 108 109 109

Contents

ix

Scavengers: Hindered Amine Light StabiUzers Synergists with HALS Polymeric Stabilizers Blends Replacement of Heavy Metals Selection of Antioxidants for Use with UV Stabilizers Concentrates, Masterbatches New Chemistry Recent Developments

109 110 111 111 111 112 113 113 113

Mod if)îng Specific Properties: Flammability - Flame Retardants 10.1 How They Work 10.2 Summary of FR additives 10.2.1 Reactive FRs 10.2.2 Additive FRs 10.2.2.1 Inorganics 10.3 Halogenated Compounds 10.3.1 Chlorinated compounds 10.3.2 Brominated compounds 10.4 Other Flame Retardants 10.4.1 Melamine cyanurate (MC) 10.4.2 Zinc borate 10.4.3 Zinc hydroxystannate (ZHS) and zinc stannate (ZS) 10.4.4 Zinc sulphide 10.4.5 Metal hydrates 10.5 Phosphorus 10.6 Intumescent Flame Retardants 10.7 Halogen-free Systems 10.7.1 Wire and cable compounds 10.8 Combinations of Flame Retardants 10.9 Synergistic Reactions 10.10 Health and the Environment 10.11 Recycling 10.12 New Developments 10.13 Nano-composites 10.14 Commercial Trends

115 115 116 118 118 118 120 121 122 123 123 124

9.5 9.6 9.7 9.8 9.9 9.10 9.11 9.12 9.13

Chapter 11 Modifying Specific Properties: Conductivity - Antistatic/Conductive Additives

11.1 11.2 11.3 11.4 11.5 11.6

Classificationof Antistatic Additives Conductive Additives ESD (Electrostatic Discharge) Compounds EMI (Electromagnetic Interference) Compounds Metallic Additives Coated Polymers

125 125 125 126 127 128 129 130 132 135 136 137 138 139

141

143 143 144 144 144 147

X Additives for Plastics Handbook

11.7 11.8 11.9

Intrinsically Conductive Materials Moulded Circuitry Recent Developments

Chapter 12 Modifying Processing Characteristics: Curing and Cross-linking

12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 12.9 12.10 12.11 12.12 12.13

The Curing Process Terminology Curing Agents, Accelerators Inhibitors Curing with Accelerators Curing without Accelerators Selecting a Curing System Curing Agents for Epoxy Systems Cure Promoters UV Cure Initiators New Developments Thermoplastics Cross-linking Commercial Trends

Chapter 13 Modifying Processing Characteristics: Couplings Compatibilizing Agents

13.1

New Developments

Chapter 14 Modifying Processing Characteristics: Plasticizers

14.1 14.2

14.3 14.4 14.5 14.6 14.7

The Function of Plasticizers Main Types of Plasticizers 14.2.1 Phthalates 14.2.2 Sebacates and adipates 14.2.3 Fatty acid esters 14.2.4 Oligomeric/polymeric plasticizers 14.2.5 Epoxies Extenders and Secondary Plasticizers Health and Safety of Plasticizers Reducing the Level of Plasticizers Recent Developments Commercial Trends

Chapter 15 Modifying Processing Characteristics: Blowing Agents

15.1 15.2 15.3 15.4

15.5

The Function of Blowing Agents Physical Blowing Agents Chemical Blowing Agents (CBAs) Structural Foams 15.4.1 In-house gas generation 15.4.2 Nucleating agents 15.4.3 Dispersion agents Syntactic Structural Foam

148 148 149 151

151 152 152 153 154 154 155 157 160 160 160 162 164

167

168 169

169 170 170 171 171 172 173 173 173 174 175 175 177

177 178 179 180 181 181 181 181

Contents

15.6

15.7

Replacement of CFCs 15.6.1 Flexible foams 15.6.2 Rigidfoams 15.6.3 Pentane 15.6.4 Expanded polystyrene 15.6.5 Economics of CFC replacement 15.6.6 Testing the insulation value of blowing agents New Developments 15.7.1 Liquid carbon dioxide

Chapter 16 Modifying Processing Characteristics: Modifiers and Processing Aids

16.1

Impact Modification 16.1.1 Impact modifiers for PVC 16.1.1.1 MBS modifiers 16.1.1.2 ABS modifiers 16.1.1.3 Acrylic modifiers 16.2 Elastomer Modification 16.2.1 Acrylic rubber 16.2.2 Styrenics 16.2.3 Polyolefins 16.2.4 Polybutene 16.3 Dimer Acids 16.4 Calcium Carbonate 16.5 Modification of CPEE Polymers 16.6 Modification of PMMA with Silicon and Phosphorus 16.7 Impact Modifiers for Thermosetting Resins 16.8 Processing Aids 16.8.1 Low-temperature flexibility 16.9 Clarifying/Nucleating Agents 16.10 Fluoropolymers 16.11 New Developments 16.11.1 Core-shell rubbers 16.11.2 Silicones 16.11.3 Modification of engineering thermoplastics Chapter 17 Modifying Processing Characteristics: Lubricants^ Mould Release Agents, Anti-slip and Anti-blocking

17.1 17.2

Lubricants for Performance Improvement Lubricants as Processing Aids 17.2.1 Metallic stearates 17.2.2 Hydrocarbons 17.2.3 Fatty acid amides and esters 17.2.5 Polyolefin waxes 17.2.6 Polyamides 17.2.7 Fluoropolymers

xi

182 183 183 184 185 186 186 186 187

189

189 190 190 190 191 192 193 193 194 195 195 196 196 197 197 198 200 200 202 203 203 204 204

205

205 206

207 207 208 210 210 211

xii


17.3 17.4 17.5 17.6

17.2.8 Silicones 17.2.9 Boron nitride Combination and Modification Release Agents for Thermosets Anti-blocking, Anti-slip Additives New Developments

Chapter 18 Other Types of Additive: Miscellaneous Additives

18.1

Anti-bacterials and Biocides 18.1.1 Anti-allergy agent 18.2 Degradation Additives 18.3 Shrinkage Modifiers, Low-profile Additives 18.4 Improved Barrier Properties 18.4.1 Gas barrier coating 18.4.2 Resorcinol additives 18.4.3 Plasma technology 18.4.4 Oxygen absorption in food packaging 18.5 Hard Coatings 18.6 Thermal Insulation 18.7 Fragrance 18.8 PVC Matting Agent 18.9 Anti-fogging 18.10 Acoustic Insulation 18.11 Surfactants, Foam Control Additives 18.12 Mould Treatment Agents Chapter 19 Other Types of Additive: Additives for Rubber

19.1 19.2

Guidance on Safety New Developments 19.2.1 Silica

Chapter 20 Other Types of Additive: Additives for Recycling

20.1 20.2 20.3 20.4 20.5 20.6 20.7 20.8

Stabilizing, Re-stabilizing Stabilizers Improvement of Properties 20.3.1 Fibres/compatibilizers/impact modifiers Desiccants PE/PVC Compatibilizing Melt Flow/Viscosity Modification Additives for Identification of Plastics Equipment for Recycling

212 213 213 214 216 216 219

219 221 221 222 222 223 223 224 224 225 22 5 226 226 226 227 228 229 231

233 233 233 237

23 7 238 239 239 239 240 240 241 244

Chapter 21 Background Information: Equipment - Mixings Compounding^ and Dosing

21.1 21.2

Incorporation of Additives Mixing Thermosets

245

245 246

Contents

21.3

21.4 21.5

Mixing Thermoplastics 21.3.1 Drymixers 21.3.2 Calendering 21.3.3 Extrusion compounding 21.3.4 Compounding mineral fillers 21.3.5 Fine talc masterbatch 21.3.6 Single- and twin-screw extruders 21.3.7 Adjustable screw geometry Colour Dosing Recent Developments

Chapter 22 Background Information: Health and Safety

22.1

22.2

22.3

22.4

22.5 22.6

Hazards by Additive 22.1.1 Carbon black 22.1.2 Titanium dioxide 22.1.3 Flame retardants 22.1.4 Glassflbre 22.1.5 Styrene monomer 22.1.6 Isocyanates Hazards During Production, Storage, and Transportation (Workers) 22.2.1 Fire/explosion 22.2.2 Emissions 22.2.3 Skin/body contact 22.2.4 Dust Hazards During Use (Direct Consumer and General Public) 22.3.1 Toxicity-food contact 22.3.2 Flame retardants 22.3.3 Plasticizers Hazards During Disposal (Workers and General Public) 22.4.1 Landfill-heavy metals 22.4.2 Incineration HealthandSafety at the Workplace: Some Guidelines 22.5.1 Reduction ofemissions at the workplace New Developments: Solvents

Chapter 23 Background Information: Legislation and Testing

23.1 23.2 23.3 23.4 23.5 23.6

xiii

247 247 248 248 249 249 250 251 252 253 257

257 257 258 259 259 2 59 260 260 261 261 261 262 262 263 263 264 266 266 267 267 268 268 269

Blowing Agents 269 Flame Retardants 269 23.2.1 Halogenated and brominated flame retardants 2 71 Heavy Metals/Cadmium Pigments 2 71 Plasticizers 2 72 Food Packaging 2 73 Migration Levels 2 74

xiv


23.7

Moves to Establish a Threshold of Regulatory Concern (TRC) 23.7.1 US history 23.7.2 European history 23.8 The User's Viewpoint 23.9 Medical Products and Packaging 23.10 Waste and Recycling 23.10.1 Packaging 23.10.2 Electrical and electronics 23.10.3 Automobiles 23.11 Physical Testing 23.11.1 Mechanical tests 23.11.1.1 Tensile strength and modulus 23.11.1.2 Flexural strength and modulus (ISO 178 and ISO 3597) 23.11.1.3 Compressive strength (ISO 3604) 23.11.1.4 Shear strength 23.11.1.5 Impact strength 23.11.2 Thermal testing 23.11.2.1 Heat stability 23.11.2.2 Light stability 2 3.11.3 Electrical properties 23.11.3.1 Surface and volume resistivity 2 3.11.3.2 Surface resistivity 23.11.3.3 Electrostatic discharge 23.11.3.4 Static decay 23.11.4 Flammability 23.11.5 Heatrelease 23.11.6 Ease of ignition 23.11.6.1 Calorificvalue: ISO 1 7 1 6 calorific value of materials 23.11.6.2 Flamespread 23.11.7 Smoketests 23.11.7.1 AS 1530: Part 3 - t e s t for early fire hazard properties of materials 23.11.7.2 DIN 4102 Part 1 - B l Brandschacht test 23.11.7.3 VDE 0472 Part 804 23.11.7.4 FAR Part 2 5: Federal Aviation Regulations for materials used in aircraft 23.11.8 Fire tests for building materials 23.11.9 Combustibility 23.11.10 Floor covering

2 76 276 2 76 2 77 2 77 277 278 2 78 279 279 280 280 280 280 281 281 282 282 283 283 283 283 284 284 284 286 286 286 286 287 288 288 288 288 288 289 290

Contents

23.11.11 New developments 23.11.12 Analysis 23.11.13 Surface quality tests 23.11.13.1 Barcol hardness test 23.11.13.2 Acetone sensitivity 23.11.13.3 Surface analysis 23.11.14 Colour testing 23.11.14.1 Colour stability Database Appendix A: Conversion Tables Appendix B

xv

292 292 292 292 293 293 293 294 294 295 299

Technical Terms Standards and Testing Institutions Recommended Books and Journals Manufacturers'handbooks Journals covering additives for plastics and rubber

299 302 303 303 304

Appendix C: Standard Abbreviations for Plastics and Elastomers

307

Appendix D: Trade Names

311

Appendix E: Directories

327

Directory of Suppliers Industry Associations and Federations

32 7 3 64

Fillers and extenders Reinforcements, fibrous and microspheres Pigments, colorants, whites, blacks Antioxidants and stabilizers: heat and light Flame retardants Antistatics and conductive additives Curing, cross-linking agents Property modifiers, processing aids Plasticizers Blowing Agents, Dispersants, Miscellaneous Additives Lubricants, release agents, slip/anti-block

369 386 392 399 405 414 417 420 423 428 430

Data Sheets

369

Editorial Index

445

Index of Advertisers

471


LIST OF TABLES Table 1.1 Table 1.2 Table 1.3 Table 3.1 Table 3.2 Table 3.3 Table 4.1 Table 4.2 Table 4.3 Table 4.4 Table 4.5 Table 4.6

Table Table Table Table

5.1 5.2 5.3 5.4

Table 5.5 Table 5.6 Table 5.7

Types and uses of additives The main effect of additives on the properties of a compound Main types of additive for plastics, and their functions World production and consumption of major thermoplastics, 1 9 9 9 - 2 0 0 5 (thousand tonnes) Regional production and consumption of thermoplastics, 1 9 9 9 - 2 0 0 5 (% of total) Recent mergers and takeovers in the additives sector, 1 9 9 7 - 2 0 0 0 At a glance: fillers Common fillers and reinforcements for plastics Some properties of silica particles and the amounts of added silanes for surface treatment Properties of a nano-composite P A6 compound, compared with conventional reinforcement Polypropylene nano-composite made by a slurry process compared with conventional compounds Physical properties of nano-tubes in polycarbonate At a glance: fibre reinforcements A quick guide to the relative properties of fibres Comparison of commonly used reinforcing fibres Typical properties of continuous pitch-based carbon fibres (based on BP Amoco Thornel grades) Typical properties of continuous P AN-based carbon fibres (based on BP Amoco Thornel grades) Main properties of glass fibre Glass fibre: comparison of E-and E-CR glass

14 17 17 19 20 17 33

34 35

37 39 40 42 42 44 45

xviii


Table 5.8 Table 5.9 Table 5.10 Table 5.11 Table 5.12 Table 6.1 Table 6.2 Table 6.3 Table 7.1 Table 7.2 Table 7.3 Table 7.4 Table Table Table Table

7.5 7.6 7.7 7.8

Table 7.9 Table 7.10 Table Table Table Table Table

7.11 8.1 8.2 8.3 8.4

Table 8.5 Table 8.6 Table 8.7 Table 9.1 Table 9.2

Long fibre-reinforced thermoplastics: effect of fibre length 52 Properties of typical long-fibre thermoplastic compounds 53 Long-fibre plastics compared with die-cast metals (2 3°C) 53 Cost comparison between glass fibre and carbon fibre, specific mechanical properties (glass cost = 1.00) 56 Capacities for carbon fibre, worldwide, 56 1 9 9 6 - 2 0 0 0 (tonnes) At a glance: pigments, dyes, special effects 58 Replacements for cadmium pigment master62 batches Influence of pigment type on dimensional plates 68 At a glance: white pigments 73 Melt flow index of polycarbonate, pigmented with 5% Ti02 showing the effect of various surface treatments 75 Comparison of the hardness of pigments 78 Zinc sulphide compared with titanium dioxide for glass-reinforced thermoplastics 79 Properties of white pigments and fillers 81 82 Typical grades of white masterbatch 84 At a glance: black pigments Effects of changing particle size or structure on 86 specific peoperties of carbon black Effects of changing both particle size and structure on specific peoperties of carbon black H7 Variations in carbon black produced by different processes 89 Typical grades of black masterbatch (universal) 90 93 At a glance: heat stabilizers 95 Polymer heat stabilizers: selection guide Stabilizer systems in different PVC applications 99 Extrusion compound for window profiles; comparison between a classical lead formulation and tin maleate (Thermolite 410) 99 Flexible PUR foam scorch evaluation: delta E after microwave test 101 Effect of the structure of HAS on the colour strength of a compound 102 World consumption of stabilizers (thousand 106 tonnes) 107 At a glance: UV stabilizers 112 UV stabilizers: selection guide

List of Tables xix

Table 9.3 Table 10.1 Table 10.2 Table 10.3 Table 10.4 Table 10.5 Table 10.6 Table 10.7 Table 10.8 Table 10.9 Table 10.10 Table 10.11 Table Table Table Table

10.12 10.13 10.14 10.15

Table 11.1 Table 11.2 Table 11.3 Table Table Table Table

11.4 12.1 12.2 12.3

Table Table Table Table

12.4 12.5 12.6 12.7

Table 12.8 Table Table Table Table

13.1 14.1 14.2 15.1

Typical UV stabilizing systems in masterbatch form At a glance: flame retardants Summary of the main FR additives Eff'ectofchlorinatedFR additives on PE and PP compounds Effect of varying ratios of chlorine and bromine on ABS compounds Effectofindividualfillers (UL 94 test ofPP) Influence of intumescent gel coats on fire behaviour of composites (RTM process) Examples of halogen-free flame-retardant grades (M A Hanna Group) General wire and cable specifications to meet BS7211 Effect of a mineral filler/melamine combination with PP on LOT and UL 94 tests FR formulations using various synergists Halogen compounds found effective with antimony oxide Flame retardants: selection guide Cost and properties of flame-retarded PP ConsumptionofFRsby major region ConsumptionofFRsby type and region, 1998 (thousand tonnes) At a glance: anti-static/conductive additives Classification of electrical insulation/ conductivity Performance of stainless steel fibres at various loadings Comparison ofdifferent conductive systems At a glance: curing systems Applications of organic peroxides Cross-linking with peroxides: dosage of peroxide per 100 parts polymer Curing systems and when/where to use them Curing agents for epoxy resins General specifications for BS7211 Advantages and disadvantages of available cross-linking methods Use of radiation-cured products in the USA, 1 9 8 9 - 2 0 0 3 (tonnes) At a glance: coupling, compatibilizing agents At a glance: plasticizers Main types of plasticizers At a glance: blowing agents

113 115 116 121 123 126 12 7 128 129 131 132 134 135 138 139 139 141 142 147 147 151 152 153 155 161 163 164 165 168 169 170 177

XX Additives for Plastics Handbook

Table 15.2 Table 15.3 Table 15.4 Table 16.1 Table Table Table Table

16.2 16.3 16.4 16.5

Table 16.6 Table 17.1 Table 17.2 Table 17.3 Table 17.4 Table 18.1 Table 19.1 Table 20.1 Table 20.2 Table 22.1 Table 23.1 Table 23.2 Table 23.3 Table 23.4 Table 23.5 Table 23.6 Table 23.7 Table 23.8

Blowing gases for plastics Typical processing temperatures for thermoplastics Replacement of blowing gases for expanded polystyrene At a glance: process modifiers and processing aids A quick guide to impact modifiers Kraton G as a compatibilizer Typical processing aids Clarified polypropylene compared with other transparent packaging materials Eff'ectsofPPA-l onprocessability ofHDPE resins (capillary rheometry 190°C) Typical lubricants for various thermoplastics Characteristics of acrylic processing aids Effect of an internal lubricant on injection moulding of electrical housing and cap Typical high-slip and anti-blocking masterbatches Acoustic properties of some commonly used materials Additives used in rubber compounding At a glance: additives for recycling Forms of waste, processing lines and potential recycled products Typesof additives and their potential hazards Summary of relevant environmental legislation German BGA limit values for migration of elements from raw materials (DIN 53 7 70) Permissible migration in toys (European Norm EN 71-3) A guide to food-contact additives Tests designed mainly for rigid materials Tests designed mainly for flexible materials UL 94 requirements EC classification of fire tests for construction products

178 180 186 189 191 194 199 202 203 205 209 210 215 228 2 32 2 37 243 2 58

2 70 2 74 274 2 75 285 285 287 291

LIST OF FIGURES Figure 2.1

Figure 2.2

Figure 4.1. Figure 5.1.

Figure 6.1.

Figure 7.1.

Figure 11.1.

Figure 11.2. Figure 16.1.

Acting like a plastic 'sponge', Accurel is one of the new systems for introducing additives homogeneously to a granular compound. (Photograph: Akzo Nobel) 6 Many types of additives, such as stabilizers, are now supplied in forms that are easier and safer to handle and use. (Photograph: Akcros Chemicals) 8 A typical compounding line for reinforced thermoplastics. (Illustration: FTP Co) 22 Polypropylene is reinforced with chemically coupled glass fibre for injection moulding this Whirlpool washing machine tub, giving high performance for low cost. (Photograph: Ticona) 38 Structures of inorganic pigments: (top) rutile-cassiterite structure of inorganic colour pigments and (bottom) the spinel structure. (Illustration: Ferro Corporation) 59 Diagram of carbon black molecules illustrates how the size and structure influence the processing and properties. (Illustration: Cabot Corporation) 85 Carbon black additives can also conduct electricity, offering a simple and effective means of providing anti-static properties or EMI shielding. (Photograph: Cabot Corporation) 145 Carbon black particles. (Photograph: Cabot Corporation) 146 A new dimension for polypropylene is signalled by the development of clarifying agents, such as Millad. (Photograph: Milliken Chemical) 201

xxii


Figure 17.1.

Figure 21.1.

Figure 21.2.

Figure 21.3.

With an average particle diameter of 4.5 /xm, Tospearl is an advanced silicone anti-blocking agent. (Photograph: GE Silicones) 217 For better compounding efficiency, recent barrier screw designs by Davis-Standard include (top) DSB-V, with variable-pitch barrier flight, and DSB-V I, with a dual-barrier design and variable lead barrier flight. (Photograph: Davis-Standard) 2 52 Powerful shearing and homogenizing of sensitive materials, retaining vital rheological properties, is provided by Farrel Corporation's Advex. (Photograph: Farrel Corporation) 2 53 Looking towards a new market demand, the Davis-Standard Woodtruder combines in a single system the latest plastics extrusion technology with technology for processing wood fibre. (Photograph: Davis-Standard) 2 54

Preface Both technically and economically, additives form a large and increasingly significant part of the polymer industry, both plastics and elastomers. In the five years since the first edition of this handbook, there have been wide-ranging developments, covering the chemistry and formulation of new and more efficient additive systems and the safer use of additives, both by processors in the factory and, in the wider field, as they affect the general public. It has also become clear that, to meet today's requirements, the budgets for research and development and the structure needed to maintain a global presence are beyond the resources of individual companies, resulting in many mergers and takeovers, leading to the creation of a few world-scale giant producers, complemented by a number of specialists. This second edition follows the successful formula of the first, presenting a comprehensive view of all types of additives, concentrating mainly on their technical aspects (chemistry/formulation, structure, function, main applications) with notes on the commercial background of each. Whereas reports concentrate on only one sector (such as pigments or 'performance' additives), in this handbook we have again expanded the field to include any substance that is added to a polymer to improve its use, so including reinforcing materials (such as glass fibre), and carbon black and titanium dioxide. As with the first edition, this information is again presented in a more 'userfriendly' form, starting from the information requirement of the user, and so classifying additives by the properties that they offer and the appUcations in which they are used. To avoid excessive cross-referencing, there may be some repetition, but it is hoped that the advantages of this form of presentation will outweigh any disadvantage. JSM, June 2001 Publishers' note Sadly, just before completion of this book the author, John Murphy, passed away. Elsevier Advanced Technology has endeavoured to complete this work to John's very high standards. We hope that Additives for Plastics Handbook will live up to John's expectations and prove to be an invaluable aid.


Adding value to polymers

Slip & Antiblocking Fatty Acid Amides Amides Concentrates

Antistatic Fatty Amine Ethoxylates Fatty Amide Ethoxylates Glycerolmonosteatate Sodium Alkane Sulphonate Concentrates High Purity

Electroconductive Black Non-Aromatic

Flame Retardant Processing Aids

1U_ AKZO NOBEL

www.poiymerchemicals.com


CHAPTER 1 An Overview of Additives From the very beginnings of the plastics industry, it has been necessary to add materials to a basic polymer resin in order, at least, to make it processable. It has also been clear that additive materials are necessary to modify a resin, to improve properties that are desirable, and to eliminate or mitigate properties that are undesirable. In developing additive systems, the plastics industry has learnt much from the earlier experience of the rubber industry, but the pace of development responding to market needs has produced research in completely new fields, developing additive systems using new chemistry. While the plastics industry is a major user of additives, it is not the only one. Additives overall can be classified as follows:

Table 1.1 Types and uses of additives Type

Main applications

Additives

Products, normally used in small quantities, which enhance the value of materials such as plastics, paints, colour prints, and lubricants, by improving their processability, performance, and appearance during manufacture and in use.

Antimicrobials

Substances that prevent the growth of microbes and give consumer products such as soaps and toothpastes a medicated property.

Coatings

The broad term for paints, inks, and lacquers. While often associated with decoration, coatings also protect surfaces from corrosion and damage.

Colours

Can be soluble dyes for textiles, leather, paper, or insoluble pigments for plastics, coatings, and printing inks.

Fine chemicals

Highly complex functional intermediates or ingredients for 'high-tech' applications; for example, in the pharmaceutical, agrochemical, and electronic industries.

Heat and light stabilizers

Additives that prevent the degradation of plastics and coatings under the effects of heat, oxygen, and light.

Optical brighteners

Chemicals which impart whiteness to textiles, detergents, paper, fibres, and plastics.

2

An Additives for Plastics Handbook

Type

Main applications

Photo/repro additives

Additives that, when irradiated with light, promote the hardening of printing inks, coatings, and adhesives, and chemically fix images used in electronic or graphic materials.

Pigments

Colorants that remain undissolved before, during, and after application: they are used to colour plastics, inks, paints, and synthetic fibres.

UV curing

Hardening of coatings and adhesives by means of ultraviolet light.

Water treatments

Help purify water for industrial and domestic applications. They also modify water as an agent for the processing of minerals and oils, and have a variety of properties to process water (for example, flocculants separate water from solid particles).

Source: Ciba Specialty Chemicals

For plastics, the range of additives is very large, involving the improvement of many properties:

Table 1.2 The main effect of additives on the properties of a compound

Physical properties Thermal conductivity Heat deflection temperature Abrasion resistance Impact strength Tensile strength Flexural strength Compressive strength Dielectric constant Processing Exotherm Thixotropy Machinability Cost reduction Key: - decreases; ++ increases; = essentially no effect.

Calcium carbonate, calcium silicate. powdered aluminium. or copper

Chopped Mica, Alumina, flint powder. glass silica. carborundum. powdered or flaked silica, molybdenum glass disulphide

Metallic Colloidal fillers or silica, alumina bentonite clay

++ ++

++ ++

++ ++

++ ++

++ ++

=

= -

++

-

-

++

++ ++ ++ ++ ++ ++

++

= = =

++

= = =

++

= = = =

-

=

= -

=

-

++

=

++

-

++

++

-

++ ++ ++

An Overview of Additives

3

Table 1.3 Main types of additive for plastics^ and their functions Type

Examples

Functions

Fillers and mineral reinforcements

Calcium carbonate, talc, mica

Adding bulk to a compound: increasingly used to improve stiffness, surface hardness

Fibre reinforcements

Aramid, carbon, glass, natural fibres

Mechanical strength: used as short fibre, long fibre, spheres

Colorants

Pigments, liquid colours, colour pastes, dyestuffs, special effects

Virtually unlimited, added as powders or liquids: easier mixing, replacement of heavy metals

Black and white pigments

Carbon black, titanium dioxide

Also for improved UV resistance and (carbon black) electrical conductivity

Heat resistance

Antioxidants and stabilizers

Act to delay/prevent oxidation of polymer under heat, during processing or application

UV resistance

UV stabilizers

Delay/prevent oxidation of end-product under prolonged exposure to sunlight

Flame retardants

Reactive, additive, other systems

Prevent ignition of polymer, promote extinguishing: types not producing smoke or fumes

Antistatics, conductives

Antistatic/conductive additives

Increase electrical conductivity, to prevent electrostatic discharge, sticking/clinging (e.g. films)

Curing systems for thermosets

Accelerators, curing agents, and catalysts

Initiate and control the cure of thermosetting resins

Cross-linking, coupling, compatibilizing

Forming cross-links between suitable polymer and other molecules

Cross-linking agents for thermoplastics; coupling agents, compatibilizers to promote bonds between polymers and additives

Plasticizers

Mainly phthalates, but many systems are used

Improvement in processability, flexibility: used mainly in PVC, but limited use in other plastics

Process modifiers, processing aids

Lubricants and plasticizers, nucleating agents

Improvement of mixing/blending; control of viscosity

Blowing agents

Inert gas or gas-forming chemicals injected or mixed into a compound to react during processing

Production of foams and expanded plastics; replacement of chlorofluorocarbons (CFCs)

Lubricants

Lubricants, mould release agents, slip and anti-block

Improvement in processing; release properties; reduced slippage and blocking with films

Other types

Barrier properties, shrinkage, acoustics, surfactants, antimicrobials

Giving specific properties

RecycUng additives

Impact modifiers, stabilizers

Used to improve/protect properties of waste plastics during mechanical recycling


CHAPTER 2 Types of Additive and the Main Technical Trends Additives are becoming more technical, doing more work, offering greater value, and so commanding a higher price. PVC is still by far the largest user, in volume terms, but polyolefins have emerged as a growing second-runner and the development of engineering plastics has opened up a fast-growing market for speciality additives, ranging from flame retardants to stabilizers, pigments, and processing aids that will resist the higher processing and service temperatures involved. These naturally impose more critical performance requirements. Many additives have more than one effect on a plastics compound. Plasticizers will often aid in processing and lubrication. Light stabilizers also have an effect of weathering. Carbon black, which is widely used as a pigment, also functions as a light shield, as an electrically conductive component, and as a reinforcement.

2.1 Current Lines of Development

A main line of development now is multi-functional additives, such as reinforcing fillers: talc is added to polypropylene to improve stiffness and heat stability, pigments can aid in UV protection, plasticizers also function as lubricants and anti-static agents. A potentially fertile field is that of synergism between components, where better performance in vital properties such as weathering and flammability can be achieved by using lower concentrations of synergistic additives. The aim, all along, is to simplify operations at the compounding or processing level and to remove the need for precision weighing and metering of very small amounts. Delivery of additives in a more convenient and safer form is also high on priority lists. This obviously calls for significant research and development budgets and capital expenditure in more sophisticated production/processing plants, which has the effect of raising the entry cost all the time for new producers. A further cost pressure is the necessity of complying with legislation, often worldwide - and to be able to provide customers right down the line with documentation to prove compliance. There is also active development of surface-modification technology, to render fillers of all types (especially inexpensive mineral fillers) more acceptable

6


Figure 2.1. Acting like a plastic 'sponge', Accurel is one of the new systems for introducing additives homogeneously to a granular compound. (Photograph: Akzo Nohel)

to the matrix and improve interfacial bonding, for better, more durable mechanical properties. A third major line of development is to meet increasingly strict regulations for health and safety, both in the workplace and in public use. This particularly affects flame retardants (where concern has been expressed about possible escape of flame-retardant components during storage, under heat and flame, and in recycling) and pigments (where legislation has centred on the use of heavy metals in pigment formulations, possibly creating hazards in disposal of the product). 2.7.7 Fillers

Filler technology is shaping an entirely new and 'active' role for these very traditional materials, especially using coating and other surface treatments to confer other properties, such as pigmentation and processing assistance. Expandable fillers continue to be promising. Calcium carbonate is the most important filler, in terms of volume, but is relatively low in value. In the plastics industry, it has mainly been used in PVC compounds, but 'engineered' grades (produced by adjusting particle size or geometry, and/or modifying the surface) are opening up a large potential market in polyolefins, where the aim is not to extend the bulk of the compound but to offer positive properties, such as reducing cycle time and improving physical properties. For example, very fine particles give marked increases in the


7

strength of films. Stearic acid-coated grades give good mechanical properties and improved processing. Suitable calcium carbonates can be used in part replacement of white pigment and to achieve high gloss (and to offset the reduction in gloss produced by replacement of lead stabilizers with calcium/zinc systems). Other mineral fillers are coming into prominence, as users demand more and more of compounds. Talc, mica, and wollastonite improve stiffness, heat stability, and expansion/shrinkage, and certain clays in sub-micrometre particle sizes (nano-particles) are currently the focus of research, to improve mechanical and also barrier properties, for very small percentage loadings. A new area of development is to incorporate the filler permanently into the polymer matrix, by use of coupling reactions. This can increase impact strength and thermal properties of polyamides and modify the anisotropy of partially crystalline plastics, such as polyamides and polyesters. In polypropylene, bonding with kaolin can also improve scratch resistance, which is a useful benefit for automobile interior applications. Surface modification of fillers such as silica, mica, and wollastonite allows these to penetrate markets that were formerly the province of reinforcements such as carbon black and glass fibre. 2.7.2 Pigments

Regulations are still the key problem, as manufacturers strive to come up with effective pigments that also meet the heavy metal-free legislation. High concentrations are also important, to save costs, but there is also fast-growing interest in pigments to produce special effects, such as pearlescence and edgeglow, and also strong interest in systems for laser marking. The main trend is still the development of alternatives to classic pigments based on heavy metals, such as cadmium. While, ironically, voices are now being raised questioning whether cadmium pigments are really such a danger to the environment, new pigment systems are being commercialized that can effectively replace them and give brilliance that is comparable. Colorants in liquid form are another area of study, to give processors the flexibility of changing colours within a production run, and pigments that give novel effects (such as metallics, pearlescents, and 'flip-flop' colour changes) are increasing in popularity. 2.7.3 Plasticizers

While the plasticizers sector (which is almost totally bound up with PVC) has been dominated in recent years by controversy over the use of phthalates, there has been significant development in systems based on other materials, such as polymeric plasticizers. Lubricants and processing aids also come into this classification, where the trend is towards adaptation to other plastics compounds, both standard and engineering plastics, and new systems that reduce or overcome migration, for use especially in food contact and medical/ healthcare applications.

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Figure 2.2 Many types of additives, such as stabilizers, are now supplied informs that are easier and safer to handle and use. (Photograph: Akcros Chemicals)

2.1.4 Stabilizers

Stabilization (against both heat and light) is a main object of development, using new chemistry and fulfilling new market niches. Stabilizers are increasingly needed in engineering plastics, to stabilize the compound during processing at higher temperatures and/or to provide stability for the application during continued exposure to elevated temperatures and/or outdoor conditions. In this direction, the development of hindered amine light stabilizers (HALS) has been the most significant achievement, and there is also considerable research into the synergistic effects of employing two stabilizer systems in a compound. Replacement of heavy metal formulations is influencing all development, and the introduction of cadmium/zinc systems in a more effective form is significant. Classically, stabilizers have used lead compounds and, on environmental grounds, manufacturers have volunteered to reduce levels to about 60% of today's usage by 2010. Calcium/zinc systems are now not included in the European Commission Ust of heavy-metal stabilizers, and these are seen as a key material for the future. 2.7.5 Flame retardants

Flame retardants are probably the most researched group of additives today, to meet performance requirements under increasingly tight environmental conditions (which now also include behaviour during disposal of products by incineration). Recent development has been aimed especially at systems also


9

offering zero or very low emission of smoke and fumes when exposed to the heat of combustion. There is continuing controversy over the use of halogenated flame-retardant systems, and a general move towards non-halogenated/zero smoke types (especially among European legislators). The critical end products involved are housings for consumer and office electronics equipment, wire and cable sheathing, and (as a result of recent tragedies) electrical equipment and rolling stock used for railways. There is a move (also in Europe) to limit or prevent the use of flame retardants based on brominated systems, on the grounds of alleged difficulty in recycling, but this is being strongly opposed by the industry (and there is disagreement also among legislators). A consequence of the need for investment in research and development will be the rationalization of the number of types on the market, and the emergence of a limited number of grades (possibly with fewer manufacturers).

2.2 Special Additives

In terms of functions, the emphasis is now on improvement of film processing, anti-static additives, 'special effect' pigments, multi-functional fillers, and stabilizing systems for engineering plastics. Many of the new developments in individual additives are now being offered at the same time in safe, convenient technical masterbatch formulations. 2.2.7 Antistatic and conductive

additives

Conductive additives such as high-purity carbon blacks are commonly added to compounds where there is a potential hazard from electrostatic discharge. There is also extensive development of systems based on metal fibres, to give higher protection or shielding against electromechanical interference. 2.2.2 Food contact and medical

additives

Special purity requirements naturally have to be met for the many types of additives used for applications in contact with foodstuffs (such as packaging) and for medical products. For many years, world authorities have operated a degree of control over the use of additives in critical applications such as food contact and medical products. A review of the relevant legislation is given in Chapter 2 3 . In the USA, the relevant authority is the Food and Drug Administration (which also exerts considerable influence over products worldwide). In Europe, the European Union (EU) is the legislative authority. In July 2000 it ratified an EU directive on food contact, listing additives in food-contact plastics that will require migration testing. Production of compounds for use in the medical sector has become an attractive (if very demanding) 'niche' for highly qualified specialists, able to operate globally, with strong financial resources.

10


2.2.3 Clarifiers, nucleating agents,

compatibilizers

Clarifiers and nucleating agents are making considerable progress, especially in polypropylene compounds, where they improve the clarity of the compound while assisting processability and set-up. The advantages show themselves particularly in medical products and packaging. Compatibilizers are increasingly used to aid the more effective use of other additives.

2.3 Multi-functional Formulations

There is a marked trend towards multi-functional formulations (sometimes based on upgraded fillers or pigments) and single-pack formulations, such as for PVC. The aim, all along, is to simplify operations at the compounding or processing level and to remove the need for precision weighing and metering of very small amounts. Delivery of additives in a more convenient and safer form is also high on priority lists. This obviously calls for significant research and development budgets and capital expenditure on more sophisticated production/ processing plants, which has the effect of raising the entry cost all the time for new producers. A further cost pressure is the necessity to comply with legislation - often worldwide - and to be able to provide customers right down the line with documentation to prove compliance.

2.4 Masterbatches

Most resins can be coloured by masterbatch or colour concentrate, or modified with an increasing range of special additive concentrates, at dosing rates of 0 . 5 10%, but usually around 2%. The use of self-colouring, however, is growing again, with the availability of more reliable and cheaper dosing equipment, with greatest growth being in gravimetric systems. Apart from the technical advantages, including reduction/rationalization of inventory, masterbatch has economic advantages, it is claimed. Specialist Hanna notes that the cost of pre-colouration can generally be taken as about the same as that of compounding, which is about 0.2 7-0.3 kg"^. Masterbatch at 7.5 kg~^, dosed at 2% to colour a natural resin costing 0.90 kg~^ produces a cost of 0.13 kg~^. Adding the cost of the dosing equipment adds about 0.015 kg"^ to the total. Most major suppliers now offer masterbatches containing special additive formulations. A typical range is that produced by Chrostiki. It includes Mastertint black, white, colour, and special effect, Masterad slip, anti-static, and cleaning agent. Filolen masterbatch offers calcium carbonate with very high softness and dispersion, giving very high whiteness and high purity. Addition levels range from 2 to 5% for polypropylene woven tapes and big bags, to 5-20% for polyolefin injection mouldings, and 20-50% for biaxially oriented polypropylene film, thermoforming and pipe, sheet, and profiles.


11

2.5 Dendritic Polymers

DSM has commercialized new dendritic (highly branched) polymers, under the name Hybrane. Related to the original dendrimer, Astramol, these performance additives are described as 'hyperbranched'. They do not require such a perfect structure as a dendrimer, but they generally retain many of the properties characteristic of these materials. They can assume a globular-like structure, leading to low melt viscosity because there is little entanglement between the molecules. The globular molecules can also act as hosts for small *guest' molecules. Interesting results can be obtained by combining different functional groups on the same polymer. For example, one type of end-group can give compatibility with the matrix while another can provide surface-active effects or facilitate take-up of other molecules. DSM sees potential applications in plastics as rheology modifiers and compatibilizers, and, in the wider field, in adhesives, toners, detergents, and cross-linkers. Hybrane additives have also been studied for dyeing polypropylene fibres. When used as compatibilizers, they can form links with other additives such as fillers, flame retardants, stabilizers, anti-statics, and fungicides. They can take up 2 0 - 2 5% of their own weight in water (compared with the maximum 10% of which linear polymers are capable) and can easily be modified by the addition of other functional groups, including groups to regulate the migrating power of the additive in the compound during processing, possibly producing an enrichment of additive at the surface.


CHAPTER 3 The World Market Additives form a growing and valuable sector of speciality chemicals that has been selected by a number of manufacturers as a business sector. It is difficult to give an accurate estimate of the world market for additives for polymers, because the figure depends very much on what is defined as an 'additive'. There are as many different estimates as there are forecasters. Most tend to limit the field to the so-called 'performance' additives - such as plasticizers, lubricants, stabilizers, flame retardants, and anti-statics - that confer a specific property or protection on the compound. This excludes fillers and pigments, but increasingly significant portions of these are now also developed and marketed as 'performance' fillers or pigments, special carbon blacks, or titanium dioxides. So it is not surprising that there is some difference in estimates, arising to some extent from such overlaps. As well as regular market forces, other forces acting on the additives market include environmental and health issues, new technologies, inter-material competition, strategic repositioning for increased shareholder value, and customer-driven factors.

3.1 World Consumption of Additives

While the volume of additives worldwide increased by 6% from 1996 to 1998, value actually fell, by 1%, due to the Asian crisis. Trying to find some common ground between the best forecasts, it appears that the world additives market amounts to about 7.8 million tonnes, valued at about US$16 billion and is growing overall at about 3.5-4% per year. Fillers account for an estimated 50% by volume but in value they make up only 15% - and here Ues the stimulus for much current development. Asia Pacific is the largest global user of additives, accounting for some 35% of demand, by value. North America and Europe are about equal, at 28 and 25%, respectively, while the rest of the world takes up the remaining 12%. There have been dramatic changes in the additives market. The research agency Townsend considers that the world market for performance additives (flame retardants, stabilizers, anti-oxidants, modifiers, and lubricants) today

14


amounts to about 2.72 million tonnes, worth nearly US$16 billion. Flame retardants make up 3 1 % of the volume (nearly 850 000 tonnes) and stabilizers, modifiers, and lubricants each account for around 16-17% (about 430 000 to 460 000 tonnes). There is some agreement, however, over flame retardants, where forecasting agencies estimated the world market in 1996 at about 850 000 tonnes with a value of some US$2 billion, and the Western European sector in 1995 at 316 000 tonnes. Additives with a significant value have a smaller volume, and so the next largest segment is probably plasticizers, which are estimated to account for 1 million tonnes in Europe alone, worth US$1.8 billion. Next are pigments and colorants, which might account for around 2 million tonnes worldwide - but it is unclear whether this figure includes titanium dioxide and carbon black (Rapra estimates the European colorants market at 728 000 tonnes, worth US$1.2 billion).

Table 3.1 World production and consumption (thousand tonnes)

of major thermoplastics, Consumpti on

Production 1999 Polypropylene PVC Polyethylene, high density Polyethylene, low density Polystyrene Polyethylene, linear low density ABS Total

27 26 20 16 10 12

1999-2005

2005

Growth rate(%)

1999

2005

Growth rate(%)

870 188 889 121 668 033

39 924 31 821 29 160 18 147 13 307 18881

6.17 3.30 6.71 1.99 3.75 7.79

2 7 608 25 538 21075 16538 10 596 11 302

40 098 32 008 29 229 18 304 13 339 18829

6.42 3.83 5.60 1.70 3.91 8.88

3966 117735

5227 156467

4.71 4.85

3940 116597

5230 157037

4.83 5.09

Source: Enichem/ParpineUi

In terms of additive type, the best estimates suggest that, in volume terms, performance additives break down as: 69% modifiers (including plasticizers), 23% polymer extenders, and 8% process additives. In sales value, modifiers represent 51%, polymer extenders 41%, and processing aids 8%. By polymer matrix, PVC compounds account for 73% of additives by volume. Polyolefins make up 10% and styrenics 5%, while the other polymers make up the remaining 12%. In value terms, PVC drops to 59%, while polyolefins rise to 17%. Styrenics account for 7% and other polymers increase their share to 17%. This sharp difference in volume and value is a key factor in the technical development in the industry, where the trend is to upgrade performance, introducing new technology and, where possible, to simplify use of presentation with the development of multi-functional additives in a safe, more convenient form.

The World Market

15

3.2 The Market for Masterbatch

An important market for additives is in masterbatch - concentrated formulations that offer the processor a convenient means of handling additives, particularly pigments, by 'diluting' with natural material beside or actually in the processing machine. They also offer advantages in inventory size and raw materials storage space. The international compounding group Ampacet estimates that worldwide consumption of masterbatch will reach 2.15 million tonnes in 2 0 0 1 . This is a somewhat higher estimate than that given by market researchers Applied Market Information, probably due to different product classifications. Both, however, agree that the mature markets in North America, Europe, and Japan are currently consuming about 76% of the world total, and Ampacet forecasts that this share will fall to 73% in 2 0 0 1 , as demand rises in Southeast Asia and Latin America. Film (blown and cast), blow moulding, and injection moulding make up about 70% of consumption. About 56% of the total polymer consumption in masterbatch is polyolefins, estimates Ampacet, with polyethylenes making up 41.14 million tonnes and polypropylenes 24 million tonnes. Ampacet identifies the main world market trends in masterbatch as: (i) more customers are expanding worldwide; (ii) masterbatch growth is slowing in North America and Europe; and a two-tier industry will continue to evolve.

3.3 Overall Commercial Trends

The number of small suppliers is decreasing. Recent years have seen companies building and exchanging their portfolios and global giants emerging, such as Ciba Specialty Chemicals (US$5.5 billion turnover), Clariant (US$5.23 biUion), W R Grace (US$3.7 billion), Morton (US$3.33 billion), and Great Lakes (US$2.5 billion). Looking at the pattern of recent takeovers and share exchanges (see table blow), three clear trends can be identified: •

•

Globalization. Following the key end-users (especially in automobiles, electronics, medicals, and packaging) as they set up manufacturing worldwide, to be able to deliver exactly the same formulation, anywhere. This has been a feature of many recent mergers and partnerships, and also of new investment (such as in carbon black, by Columbian). Redefinition of core business and identification of key sectors, to concentrate on new technology and product development. Great Lakes has identified flame retardants as a core sector and is now looking to improve its position in stabilizers; DuPont, Millennium, and KerrMcgee have decided to stay in titanium dioxide, purchasing the assets of ICI and Bayer; and Elf Atochem has identified hydrogen peroxides as a core business. A global position in phosphates (partly as a source for flame retardants)

16


•

was also the aim of the mergers and takeovers involving FMC, Solutia, and Rhodia. Cost of new product development. Driven by competitive pressures, patent expirations, environmental regulations, and the opportunities presented by the growth of metallocene-catalyzed polyolefins and engineering resins, companies appear to be adopting a ^horizontal' approach (to concentrate on specific industries, meeting specific regulatory requirements) as well as the Vertical' approach (concentrating on specific materials and chemistries).

All in all, the additives business in recent years has emerged as a major global segment of value-added speciality chemistry.

3.4 Growth of Specialist Compounders

A significant trend in the industry is the emergence of a number of companies, usually compounders, which have identified specific product areas. A typical specialist producer is AlphaGary (itself recently taken over), which identified medical compounds as one of its key business sectors. The company claims to be the leading North American and European supplier of performance compounds, specializing in compounds for disposable medical components, as well as closures and seals, and data transmission cables. A comprehensive range of engineering plastics for medical applications has been developed by the US specialist Boedeker Plastics. Aimed particularly at equipment components and housings, it ranges from polystyrene and ABS to polycarbonate and polysulphones, meeting USP and FDA requirements. Another specialist in high-specification moulding compounds is RTF, which has commercialized a series of speciality compounds based on alloys of polycarbonate and poly(methyl methacrylate), offering greater impact strength than polycarbonate alone while maintaining the ease of processing associated with acrylics (including food-contact grades). Coded RTF 1800A Series, it incorporates selected additives such as flame retardants, EMI shielding, permanent anti-static protection, anti-wear additives, and colouring.

3.5 Regional Factors

The rate of growth of plastics consumption varies in different parts of the world, and a lesson that Western producers have had to learn in recent years is that the focus of growth is shifting away from them and towards Asia and Latin America and there is no evidence that the recent financial crises have done anything more than to delay that growth. The highest rates of growth are expected in all areas of Asia, and also in the Middle East and Africa. The world market divides roughly into four even segments, each of about 1 8 0 0 - 2 0 0 0 tonnes (US$3.7 billion-4 billion): the USA and North America, Europe, Japan, and the Asia/Facific region.

The World Market

17

Naturally, the size of each segment is directly related to the production and particularly the consumption of plastics. The relative growth of the Asia/Pacific area, both as a producer and consumer of plastics, will have a significant effect on additives, and it lies behind the number of mergers and takeovers that are occurring in the additives sector. This is clearly driving producers of fillers and additives to follow the polymer producers and adopt a more 'global' outlook, by direct investment in other regions, or by forming partnerships and alliances with local producers in other regions. This has been a key factor behind much of the recent restructuring in the industry. Table 3.2 Regional production and consumption of thermoplastics, 1999-2005 (% of total) Consumpt ion

Production 1999

2005

1999

Growth rate

2005

(%) Western Europe Eastern Europe CIS USA Canada Latin America Middle East Africa Japan Eastern Asia'' Asia/Pacific'' Total

Growth rate

(%)

24.35

23.09

3.57

24.18

21.26

3.22

2.54 1.58 24.85 2.86 5.69 3.79 1.16 8.44 16.84 7.90 100

2.57 1.75 23.09 2.65 6.61 5.36 1.37 6.82 19.25 9.48 100

5.03 6.64 3.57 3.53 7.48 11.48 7.96 1.19 7.21 8.08 4.85

2.21 1.58 24.16 2.16 7.08 1.98 2.41 7.12 18.69 7.77 100

2.27 1.53 21.26 2.00 7.52 2.24 2.46 6.62 22.52 10.17 100

5.52 4.58 2.87 3.76 6.18 7.31 5.44 3.81 7.46 9.90 5.09

'' China, Hong Kong, Korea, and Taiwan. Âustralia, Bangladesh, India, Indonesia, Malaysia, and New Zealand. Source: Enichem/Parpinelli

Table 3.3 Recent mergers and takeovers in the additives sector, 1997-2000^ Date

Purchaser

Product/division

Seller

January 1997 January 1997 January 1997 March 1997 June 1997 June 1997 November 1997 December 1997 February 1998 April 1998 March 1998 March 1998 October 1998

Joint venture Hoechst DSM Melamine Ciba Speciality Clariant ICI Great Lakes Anzon Millennium Ciba Merger Kerr-McGee Elementis Rheox Columbian

Additives Organic pigments Flame retardants Additives Red phosphorus Speciality chemicals Flame retardants Titanium dioxide 100% Carbon black/plastics Titanium dioxide Rheological additives Carbon black

Clariant (Sandoz)/Hoechst Cookson DSM/DSM Chemie Linz Merger Ciba/Sandoz Albright and Wilson Unilever Cookson R-P Thann et Mulhouse Allied Colloids Degussa/Hiils Bayer NL Industries Copebras SA

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Date

Purchaser

Product/division

Seller

November 1998 July 1998

Akzo Ciba/Witco

Elementis Witco/Ciba

July 1998 July 1998 November 1998 March 1999 March 1999 April 1999 May 1999 May 1999 June 1999 June 1999

Millennium Elf Atochem Cabot Columbian Rohm and Haas Imetal Huntsman Rhodia Great Lakes Merger

June 1999 July 1999

Ampacet Merger

50% share in Akcros Heat stabilizers/epoxies Titanium dioxide Hydrogen peroxide Aventis aerogels Carbon black Additives Calcium carbonate Titanium dioxide Flame retardants Flame retardants Phosphorus chemicals Concentrates Additives, polymers

November 1999 December 1999 March 2()()() March 2()()()

Joint venture Rohm Velsicol Albemarle

Speciality peroxides PVC processing aids Sodium benzoate Flame retardants

" This is not necessarily a comprehensive list. Source: Additives for Polymers

Titanio do Brazil Air Liquide 50% share Hoechst Korea Kumho Petro 100% Morton 100% ECC ICI Tioxide 100% Albright and Wilson FMC Corp FMC/Solutia Equistar Crompton + Knowles/Witco Akzo/Coin Chem, Taiwan Degussa/Bayer DCV Inc Ferro

CHAPTER 4 Modifying Specific Properties: Mechanical Properties — Fillers Fillers have been used by the plastics industry since its inception. It was the discovery that wood flour made it possible to mould the liquid resin phenol formaldehyde that effectively launched the industry at the beginning of the twentieth century, and subsequently PVC has proved a major user of fillers. In the intervening years, however, the use of fillers for plastics has changed significantly. While the original, basic low-performance materials such as clays and chalks are still used very widely, the modern market is placing increasing pressure on manufacturers to offer fillers that give some additional value, such as improvement in mechanical properties. They are increasingly called upon to provide other value-added functions, such as mechanical properties, UV or heat stability, thermal or electrical conductivity, dimensional stability, or flame retardancy. Increased interest in environmental aspects is creating demand now for fillers that are based on vegetable materials such as cellulose. The potential offered by a filler is determined essentially by its chemistry, and especially by its physical aspects, such as the size and geometry, surface area, and surface energy of its particles. Nevertheless, the weight of the filler remains important. Some fillers (such as barytes) are especially selected for their heavy weight, giving the compound an improvement in acoustic-deadening properties. There is also considerable interest also in fillers that are lightweight, such as hollow particles, usually ceramic or glass microspheres.

Table 4.1 At a glance: fillers Function

The basic purpose is to 'fill' a compound (increase bulk at low cost). To do this the mix must be homogeneous, with good filler/polymer adhesion, and the filler also begins to improve mechanical properties. Most particulate fillers have a higher specific gravity than polymers, but some have been developed that can reduce the weight of the compound. Geometry and surface texture fundamentally influence adhesion properties: these can be improved by surface treatment.

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Properties affected

Stiffness, hardness, shrinkage/dimensional stability; thermal stability and flame retardancy may also be improved.

Materials/characteristics

Clays, calcium carbonates, talc, silicates. Pigments such as titanium dioxide and carbon black may also have a reinforcing effect. Glass or ceramic microspheres can also offer good properties.

Disadvantages

Compounding may present problems, but surface treatments and dispersing agents will help. Solid mineral fillers add to weight.

New developments

Improved surface treatments for better dispersability, multi-functions, lightweight fillers; nano-composites.

Table 4.2 Common fillers and reinforcements for plastics Type

Characteristics/main applications

Alumina trihydrate

Extender; serving as flame retardant and smoke suppressant

Barium sulphate

Filler and white pigment; increases specific gravity, frictional resistance, chemical resistance

Boron fibres

High tensile strength and compressive load-bearing; expensive

Calcium carbonate

Most widely used extender/pigment or filler for plastics

Calcium sulphate

Extender; also enhances physical properties, increases impact, tensile, and compressive strengths Filler; used as pigment and anti-static agent, or as an aid in cross-linking; electrically conductive

Carbon black Carbon/graphite fibres

Reinforcement: high modulus and strength; low density, coefficient of expansion, coefficient of friction; conductive

Feldspar, nepheline syenite Speciality filler; easily wetted and dispersed; gives transparency/translucency; resistant to chemicals and weathering Glass fibre

Largest volume reinforcement: giving high strength, dimensional stability, heat resistance, chemical resistance

Kaolin

Second-largest extender/pigment by volume: mainly used in wire and cable, PVC flooring, SMC/BMC

Metal fillers, filaments

Electrical and/or thermal conductivity or magnetic properties; reduce friction: expensive

Mica

Flake-form reinforcement: improves dielectric, thermal, and mechanical properties; low in cost

Microspheres (hollow)

Reduced weight; improved stiffness and impact resistance

Microspheres (solid)

Improved flow properties and stress distribution

Organic fillers

Extenders/fillers (wood flour, nutshell, corncobs, rice, peanut hulls)

Polymeric fillers

Reinforcement; Ughtweight

Silica

Filler/extender/reinforcement; makes more thixotropic, aiding plate-out in PVC; acts as flatting agent

Talc

Filler/extender/reinforcement: improves stiffness, tensile strength, resistance to creep Improves strength, reduces moisture absorption, higher heat/dimensional stability, improved electrical properties; high loadings possible

Wollastonite

Source: Based on Plastic Compounding Redbook


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4.1 Effect of Fillers 4.7.7 Mechanical

properties

Impact strength and flexural modulus are the mechanical properties that can most be improved by careful selection of mineral fillers, and the shape of the particle is important. Fibre-like woUastonite particularly improves the flexural modulus while cube-shaped calcium carbonate can improve both impact strength and modulus. Talc offers many options because it is capable of many different modifications and surface treatments. The high aspect ratio of glass fibres means that they can provide the greatest improvement in mechanical properties. 4.7.2 Thermal

properties

Fillers usually have a thermal conductivity about 20 times higher than plastics, and the specific heat is about 50%. By improving the heat transfer in the melt, the use of a filler may therefore give a faster set-up when moulding, and so improve the cycle time. In applications, the same effect may be useful in engineering components, improving heat dissipation and/or producing a thermal expansion closer to that of metal. 4.7.3 Moisture

content

Water-soluble compounds in the filler (such as sodium or potassium salts) may be affected by outdoor exposure, so damaging the performance of the compound. For example, an outdoor application with a calcium carbonate-filled compound may have its outer layer converted to calcium sulphide and then to calcium sulphate (gypsum) by the effect of sulphur dioxide in the air. Fortunately, gypsum is virtually insoluble in water and cannot be washed out. However, in products with a high percentage of dolomite, the magnesium carbonate eventually combines with sulphur dioxide to form water-soluble magnesium sulphate, producing efflorescence. 4.7.4 Reinforcennent mechanism of fillers

Reinforcement depends on two features: the number of interactions at the interface between polymer and filler (which is mainly controlled by the low primary particle size in conjunction with the surface activity) and the hydrodynamic effects of particle aggregation and agglomeration (which are linked with shear modulus and hysteresis during dynamic or static deformation). One key is the shape and size of the primary aggregates, which are largely dependent on the manufacturing process, but the distribution of the particles is also important, which is largely controlled by processing conditions. This is particularly true in the case of elastomeric matrices. Recent thinking is that the differences in the aggregate size distributions are particularly responsible for the processing and vulcanization characteristics of the compound.

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Methods currently used to determine this require the filler to be comminuted by means of ultrasound - but this causes severe degradation of the agglomerates in carbon blacks, and also distorts the distribution of silicas. An alternative method has been developed using transmission electronic microscopy, in which the filler morphology retained is similar to that obtained in the incorporation process. Anisometry and fractal dimension are also used as parameters for characterizing fillers, the former to predict various mechanical properties of filled compounds and vulcanizates and the latter to investigate the surface structure. Anisometry, which is always subject to distribution, is found to widen with the fillers investigated, with an increase in the dimensions of the objects detected.

4.2 Factors for Compounding

Modern compounding, especially for technical or 'engineering' plastics, may require the addition of a complex range of materials, each with its own characteristics. The sequence in which these are introduced into the compounder (and the position down the screw) is fundamentally important. Fillers, with their weight and volume, are usually brought in first, but the latest technology, in which polymerization or cross-linking takes place in the extruder, may alter the sequence. When compounding there may often be an adhesion problem between a nonpolar polymer matrix and a filler, so it is essential to obtain perfect 'wetting' of the particles by the matrix. Before it can do anything, a filler has to bond effectively with the polymer matrix. The size and geometry of the filler particles influence

Glass fibres

Granulator

RTP pellets

Figure 4.1. A typical compounding line for reinforced thermoplastics. (Illustration: FTP Co)


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the ease with which it can be compounded and the bond strength with the other components. Surface energy influences the polymer/filler interaction, and hence the mechanical properties, particularly of polar plastics. The surface energy of fillers (stated in mj m~^) is not measurable directly. High surface energies produce dispersion problems, reducing mechanical properties, but surface energy may be improved to some extent by surface coating. To assist in obtaining a good dispersion of filler/reinforcement in a compound, it may be useful to employ a dispersing agent (see Chapter 17). Typical are phosphoric esters of fatty alcohols, used to improve dispersion of alkaline fillers and pigments in thermoplastics, including polyolefins, polystyrenes, and plastisols. The additive can be introduced before the filler is added or can be premixed with the filler. In polypropylene, it is claimed that calcium carbonate loadings can be increased to 70% without significant change in mechanical properties, while Charpy impact strength is improved by better dispersion. An aggregate of calcium carbonate with a multiple surface coating (such as Omyalene G200) allows calcium carbonate to be added directly to thermoplastics during processing. The granulated product can be mixed easily with the thermoplastic and fed directly into the machine. Redispersion is very good. It can be used with all thermoplastics, and in all processes. Dosing ranges from 2 to 15% by weight for film to 10-50% for cables, sheeting, and profiles. Abrasion can be serious when using mineral fillers. Fillers with alpha-quartz components have by far the highest abrasion rate, but heavy and tabular spars and dolomite also show high abrasion compared with some calcium carbonates. The measurement value usually cited is the Mohs hardness scale, but this is not a decisive indicator. 4.2.1 Aggregation

of fillers

A continuing problem with particulate fillers is that they often will not flow smoothly, but tend to aggregate, leading to irregular distribution of the particles in a compound, with attendant processing problems, poor surface quality, and reduction in mechanical properties. Research has shown that aggregation is determined by the relative magnitude of attractive and separating forces, the most important factors influencing the homogeneity of polymer composites being the size of the particles, their surface tension, and the shear forces acting on them during homogenization. The extent of aggregation is always determined by the relative magnitude of the forces attracting and separating. In polymer composites, the most important attractive force is adhesion, while hydrodynamic forces (such as shear) lead to separation of particles. The size and surface tension of the particles strongly influence aggregation. Although the specific surface area tends to give a good indication of the aggregation tendency of a filler, the particle size distribution is more important, since individual particles tend to interact with each other. The results obtained also indicate that the properties of the powder and the suspension may yield valuable indirect information about aggregation. The

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extent of aggregation may be reduced by non-reactive surface treatment and increased shear.

4.3 Types of Fillers 43.1 Calcium

carbonate

In terms of weight, calcium carbonate is the most important filler for plastics and it is also widely used in rubber and paints. Calcium carbonate is, in fact, much more than 'chalk' (as it is universally described in the plastics industry). The term covers natural chalk, limestone, and marble - and also precipitated calcium carbonate, which has a very fine particle size, is relatively expensive, and offers some interesting properties in polymer compounds. The natural deposits in various parts of the world have large differences in chemical purity making each suited to specific applications. The material is generally very well suited to additional surface treatment and this, together with closer control over particle size and distribution, has given most producers a range of grades serving as functional additives rather than mere fillers. Calcium carbonate is still a long way from the end of its potential. In plastics, it is used mainly in PVC, both flexible and rigid. Coarser particles are mainly used, but as compound specifications become more exacting fine-particle stearic acidcoated grades are used for better mechanical and processing properties. Being white, these grades can also aid in pigmentation and can also assist gloss, including compensating for loss of gloss where lead stabilizers have been replaced by calcium/zinc systems. It is also an important component of polypropylene, alone or with talc, for rigidity and whiteness that resists weathering. Metalloceneproduced polypropylenes, with greater self-reinforcement, can tolerate higher loadings, for better whiteness. Unsaturated polyesters, such as bulk and sheet moulding compounds, make extensive use of calcium carbonate. Polymer-coated calcium carbonates based on Carrara marble and aluminium hydroxide, with pigment integrated into the coating, have been developed to overcome the problem of irregular distribution of pigments in highly engineered polyesters, such as shrink-free formulations. The latest products offer a high concentrate of 90% CaC03/10% polyolefin binder (compared with 60-70%, which is usually regarded as the limit) in pellet form, so that moulders and extruders can add the mineral direct, with good dispersion. In the mix, the mineral also acts as a heat conductor, so aiding processing and reducing the cycle time. Applications include bottles, household articles, caps and closures, and industrial packaging. For polyolefin films, grades in powder or pellet form comprise very fine particles, averaging 1 jiim in diameter, with narrow particle size distribution and surface coated with a substance compatible with organic compounds. At loadings of 60% or higher there are increases in film strength that are described as 'dramatic'. Among recent developments are grades claiming 10-40% improvement in moulding productivity as a result of faster cooling. Electrical grades for


25

thermosetting electrical insulation offer good electrical and mechanical properties, including very high operating temperatures, including calcined clay giving cost-effective performance in rubber extrusions and low-voltage cable and wire insulation. Recent modified grades of calcium carbonate (from ECC International) include an ultrafine stearate-coated grade made from pure Italian marble, giving high whiteness in rigid PVCs and optimization of the cost-performance of titanium dioxide. Special types of calcium carbonate include: • fine calcined clays: produced from highly refined china clays, and have excellent optical properties; • treated with vinyl functional silane: for use with peroxide and other free radical cross-linking systems; designed for very high-voltage EP rubber cable insulation; • treated with vinyl functional silane and a coupling agent: eliminating surface acidity; designed as an inert carrier for organic peroxides in wire/ cable applications; silane treatment gives cable insulation high electrical stability in water; • coated with aminosilane coupling agent (also used as an opacifying extender for matt emulsion paints). High-whiteness calcium carbonate (derived from pure Italian marble) comes in various grades: • • •

Milled below 45 |im: exceptional whiteness, controlled particle size, good matting characteristics; for PVC plastisols, emulsion paints, and unsaturated polyesters; Milled below 30 }im: good dispersion, low oil absorption; for PVC cables, PVC plastisols, masterbatches, DMC/BMC, acrylic sealants, and paints; Milled below 10 )im: uncoated/coated with stearic acid; high gloss, toughne ss/rigidity in thermoplastics; for uPVC extrusions, plasticized PVC cables and extrusions, polypropylene mouldings, masterbatch, and silicone sealants.

Calcites come in various forms: • • •

Microcrystalline: good colour with extremely fine particle size and amorphous shape; for PVC compounds, rubber, and high-quality paints; crystalline, surface modified with stearic acid: spherical shape, low binder demand, capable of high loadings in PVC compounds; crystalline: surface modified with calcium stearate; functional performance in compounds, capable of high loadings; for PVC and uPVC calendered sheet, injection mouldings, and polyethylene cable sheathing.

26


Chalk whitings are used as general purpose extenders. High-quality china clays provide low-cost fillers: • •

predispersed china clays; with alkaline pH, dispersing readily in aqueous media without the need for deflocculant addition; various particle sizes and brightness; highly refined china clays; ultrafine particle size and brightness.

Ball clays. These are secondary clays, processed to reduce the level of coarse particles to a minimum. They are low-cost, semi-reinforcing clays for use where colour is not important. 432

Kaolin

Kaolin was produced 150 million years ago. Its main content is kaolinite, occurring with other silicates such as mica, feldspar, and quartz or metallic oxides such as hematite and rutile. In form it consists of thin pseudo-hexagonal lamellar particles. When heated to above 500°C, kaohnite loses its water of crystallization and changes to metakaolinite, which is stable up to 960°C. Kaolin has an increasing number of uses in plastics, often related to its coupling characteristics. It is used for anti-blocking in polyethylene and PET films and as an infra-red absorber in agricultural film. This also offers the use of this additive for laser marking of moulded packaging. In PVC cables, metakaolinite can increase resistance by removing harmful ions from the matrix. Hydroxyl groups on the surface of calcined kaoUn can also participate in coupling reactions, increasing impact strength and heat resistance of polyamides. Anisotropy can also be adjusted in partially crystalline plastics, with or without glass fibre. New kaolins give excellent tensile and tear strength, and abrasion resistance in general purpose compounds where colour is not a critical factor. They also offer the processability and particle shape advantages of kaolin, and can be used as a partial replacement for carbon black, where they give good cost effectiveness. There are also grades that can partially replace carbon black, improve the flow properties of glass-reinforced nylon, reinforce tyres, and significantly improve air retention. They can also produce 'low-profile' mouldings with good colouration, zero shrinkage, and high gloss, add flame retardancy, produce a matt finish and scuff resistance, or prevent blocking in films. 433

Magnesium hydroxide

(talc)

Hydrated magnesium silicate has a lamellar structure of thin sheets of magnesium hydroxide sandwiched between layers of silica. In plastics (especially polypropylene) it gives a good balance of rigidity and impact strength. Advanced milling technology is used to obtain the finest talcs without reducing the reinforcing power of the lamellar structure. High purity gives very good longterm thermal stability, making compounds good for use in packaging (including


27

odour-sensitive food-contact applications). With whiteness and low yellow index, talc-filled compounds are easier to colour, with a reduced pigment requirement. Some grades will also reduce shrinkage and warpage in larger mouldings. 43.4 Wollastonite WoUastonite is the subject of much development today, as a potential replacement of calcined clay and other minerals used in thermoplastics and engineered resins, and also on health grounds. New grades under development will have a higher aspect ratio in the smaller particle size ranges, where the mineral can provide increased flexural modulus and flexural strength, with improvement also in heat distortion temperature and dimensional stability. Work on high-aspect-ratio grades also demonstrates improved resistance (compared with talc) to scratching and marring, maintenance of flexural modulus, improved cold and room temperature impact strength, and reduced stress cracking at knit lines. 43.5 Silica When a particulate filler is introduced into a ductile polymer compound, the yield stress is normally decreased but, where the filler is a silica and is treated with a coupling agent it can in fact improve the yield stress. Untreated silicas in PVC compounds show a decrease in yield stress with increasing particle content and size, which is higher when the filler particles are irregular in shape than when the compounds are filled with particles of spherical shape. To improve the adhesion at the particle/matrix interfaces, treatment with a silane coupling agent (y-aminopropyl methyldiethoxysilane) increases the yield stress generally, and more so with irregular shaped than spherical particles.

Table 4.3 Some properties of silica particles and the amounts of added silanes for surface treatment Shape

Mean particle size ()im)

Specific surface area(gm"^)

Added APDES^^ (phr^)

Added HMOS"^ (phr^)

Irregular Irregular Irregular Irregular Spherical Spherical Spherical Spherical Spherical Spherical

5 11 17 27 2 6 11 17 30 51

7.8 3.0 1.9 1.2 10.9 6.2 3.0 2.1 1.5 0.9

1.91 0.73 0.46 0.29 2.67 1.52 0.73 0.51 0.37 0.22

0.26 0.10 0.06 0.04 0.37 0.21 0.10 0.07 0.05 0.03

^ y-Aminopropyl methyldiethoxysilane. ^ Hexamethyl disilazane. ^ Parts per hundred filler by weight. Source: Polymers and Polymer Composites

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The use of ultrafine silica as a reinforcement for the treads of tyres has come into prominence in recent years because, as well as offering better resistance to wet skidding than does carbon black reinforcement, it also gives better low-loss properties to the tread compound, with consequent improvement in resistance to rolling and therefore a reduction in fuel consumption. Silica resembles carbon black in its particle morphology, but the surface properties are very different (see Chapter 19). 4.3.6 Metal

powders

Metal powders for highly dense plastics compounds have been developed by Ametek Specialty Metal Products, USA. Stainless steel alloys can be used in lock hardware, appliance parts, and exhaust system components. A 50:50 mixture of irregular stainless steel powder and PTFE gives parts with cross direction elongation of 200-240%, 69065 Shore D hardness, and a bulk density of 6 0 0 1000 g 1~^. The recommended moulding pressure is 500 kg cm~^ and maximum sintering temperature is 3 75°C. 4.3.7

Microspheres

Microscopic solid glass spheres added to a plastics compound give smoothness, hardness, and excellent chemical resistance, with low oil absorption. The spheres can be used with both thermoplastic and thermosetting resins, lowering the viscosity of most resin mix systems - in fact, acting as miniature 'ball bearings' to improve flow. They have the appearance of a fine white odourless powder, in diameter ranges up to 850 jim. The precise geometry of the spheres allows even dispersion, close packing, and easy wetting out, for high filler loadings that add significantly to the dimensional stability of finished products, by reducing shrinkage and improving flatness. Specially formulated coupling agents are incorporated in coatings on the spheres for optimum performance in specific resin systems. High loadings can also increase flexural modulus, abrasion resistance, and surface hardness, and also improve stress distribution. In thermoplastic compounds, solid glass spheres can be added to most materials and used in most processes. The advantages can be summarized as:

Smooth spherical shape

- 'ball bearing'-like action improves flow in difficult mouldings - improvement in processability in fibre-reinforced compounds: better loading capacity, dispersion, and flow, improved stress distribution - up to 60% improvement in cycle time (in some cases) - low, uniform shrinkage; low warpage; close tolerances - even distribution in the resin matrix - improvement in surface finish - improved distribution of stress - reduction in wear on equipment, compared with angular fillers - very low resin absorption

Modifying Specific Properties: Mechanical Properties - Fillers High crush strength

- easily processed in injection moulding machine or extruder - virtually no breakage, even in high-shear mixing - reduction in deformation under load

Chemically inert

- no health hazard during use - can be used in most compounds

Chemically resistant

- can be used in harsh environments

Hardness

- improved abrasion resistance

Temperature resistant

- low coefficient of thermal expansion - high thermal resistance

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- resistant to most chemicals

Hollow glass spheres will displace the same volume of resin as solid spheres, but are lighter in weight: the typical density is 1.1 g cm~^ (where most mineral fillers have a density of 2.4-2.9 g cm~^). Although hollow, they will stand up to the high pressure of injection moulding with insignificant breakage of spheres. Dimensional stability, lower viscosity, and improved flow are the main advantages, but there are also improvements in mechanical properties. Loadings are generally from 5 to 15%, but some thermoplastics have been tested to 25% loading, with good results. Spherical particles can also be added to conventional glass-fibre reinforcement to compensate for directional orientation and improve the overall reinforcement effect. Tensile, flexural, and impact properties of compounds filled with hollow glass spheres are similar to those with solid spheres and research shows that there are significant benefits in properties when organosilane coupling agents are used. Lightweight, hollow, inert ceramic microspheres (Cenospheres), formed during the burning of pulverized fuel, have gained interest as a complement or alternative to hollow glass microspheres. They have a specific gravity in the range 0.55-0.75 g cm"^ (significantly lighter than conventional fillers and polymer matrices). Application depends essentially on reduction in volume cost of the compound. A plastics compound can be filled to a level of 40% by volume and still be a readily mouldable material, but without the additional weight of a solid filler such as talc. The microspheres can be direct-dosed into the moulding machine. Expanded perlite particles are friable and vulnerable in thermoplastic processing equipment, unless added at a late stage in plasticizing, where there is considerably lower shear. With a smaller size and tougher particles, ultrafine expanded perlite is claimed to offer advantages under such conditions. It is virtually impossible to avoid damaging these microspheres but, even when there is a substantial degree of breakage under processing conditions, a thin ceramic flake is produced with good potential for reinforcing and hardening the surface of a thermoplastics compound. 43.8 Expandable

microspheres

Another approach is to use thermoplastic microspheres encapsulating a gas, in unexpanded or pre-expanded form. When heated (usually at about 100°C), the

30


thermoplastic shell softens and the vapour pressure of the encapsulated gas increases, expanding the sphere 34-50 times, creating an ultralight microsphere with resilient properties. The expansion also results in reduction of surface defects, voids, and hollow parts. Expanding polyacrylonitrile microspheres, filled with pressurized iso-pentane which expand when the shell softens at moulding temperatures, are offered by Akzo Nobel Casco Products Division, under the Expancel name. New applications include shoe soles and slush-moulded PVCs. Fly ash ^floaters' - tiny hollow spheres of ash from the scrubbers of power plants - are used by the US processor Power Composites for mechanical and acoustic properties in a polyurethane mix, for moulding automobile loudspeaker enclosures. They flow easily and uniformly in the mould as part of the polyurethane mixture, giving good additional strength to the enclosure. 43.9 Cellulose fillers

The growing interest in environmentally friendly materials has produced a reevaluation of cellulose materials as fillers in plastics and, with the advantages of modern technology, some progress has been made in producing materials that are technically consistent. A cellulose granule claimed to have wide applications as an extender in plastics is derived from the woody ring of the corn cob. Named Grit-0'Cobs (marketed by Andersons) it is very hard, dense, and absorbent. Environmentally inert and biodegradable, it is reported to be virtually non-dusting and capable of absorbing more than 95% water, while retaining free-flowing characteristics. It has a pH value of 4.9, making it compatible with a wide range of active agents. Particle sizes range from grade mesh 8 to 'flour'; bulk density and absorption characteristics can be modified to suit the application and colorants can easily be added.

4.4 Surface Modification

4.4.7 Particle

geometry

To offer better value, fillers are usually coated and surface modified, and special manufacturing processes are used to control the size and geometry of the particles. Researchers are now going down to the microscopic - and even to nanoscopic - scales to modify the surface of the material and improve the interface bond. The latest work on nano-sized particles show that these submicroscopic particles can give, at 5% addition, the sort of mechanical reinforcement that needs around 40% of a conventional filler such as talc. Small particle geometry generally does not improve mechanical characteristics, except for providing more rigidity. Lamina or fibre structures with larger particle geometry normally give stabilization with improved mechanical characteristics.


31

But smaller particles may well also give increased stabilization by the increased cohesion between filler surface and polymer chain. Particle-type mineral additives are classified as two- and three-dimensional. The two-dimensional silicates in layers (such as talc and mica) essentially give rigidity and thermal stability but do not completely reach the stiff'ening effect of fibre-type reinforcements. They share high precision with three-dimensional fillers such as calcium carbonate, due to lower shrinkage anisotropy. The surface determines the number of potential polymer/filler adhesion points: a large surface gives many points, with better mechanical characteristics, but too large a surface can give dispersion problems or uncontrollable viscosity in processing. Fillers can be surface treated to improve adhesion and improve mechanical properties. The process can also improve moisture resistance, reduce surface energy and melt viscosity, improve dispersion and processing characteristics, reduce the need for stabilizers and lubricants, and improve the end-product surface. Special silane coupling agents that produce a chemical reaction with the polymer may improve stiffness and/or toughness considerably, but they tend to be expensive, and other routes are worth investigating. Thermo-oxidative stability is also important, and is influenced by trace amounts of heavy metals (iron, magnesium, copper) in most carbonates and silicates. These also influence UV stability for outdoor applications. 4.4.2 Coating Coating is increasingly used to enhance the properties of fillers. One of the most widely used materials is stearic acid. Metal stearates are particularly effective as coatings for reactive particulate fillers, such as magnesium hydroxide (MH), producing polypropylene compounds with better impact resistance than those containing uncoated, or stearic acid-coated fillers. Stearic acid will react to produce stearates, while stearates melt and form coatings. In some cases stearic acid or products of the intermediate melting temperature are produced later in the process, presumably by hydrolysis. Stearic acid produces the best coverage on calcium carbonate, but the poorest on MH. Of the metal stearates, the best filler coverage is produced when zinc stearate is used. An advantage is that hydrated inorganic fillers, in particular MH and aluminium hydroxide (ATH) and certain inorganic tin compounds such as zinc hydroxystannate (ZHS), are established fire-retardant additives for polymers. When specially coated with ZHS, MH and ATH confer significantly increased combustion resistance and lower levels of smoke evolution on plastizised PVC and polychloroprene. This permits large reductions to the additive loading without sacrificing flame-retardant or smoke-suppressant performance. Under certain conditions, ZHS and other tin compounds may also inhibit combustion in the vapour phase, functioning as non-toxic alternatives to antimony trioxide in halogen-containing formulations. Physical mixtures of ZHS and ATH also appear to give synergistic effects in PVC.

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4.5 Nano-technology

The intimacy of the filler/matrix bond is the main key to the performance of fillers and, with the latest technology, it is possible to achieve very good dispersion and an almost molecular bond. Tiny filler particles - sub-microscopic and also nanosized - have been shown to produce better mechanical properties at considerably lower loadings, and also give better flow, high barrier properties, inherent flame retardancy, and difl'erent surface textures in the same moulded part. Incorporated in a polymer matrix, typically to improve its barrier properties, they literally form a labyrinth' in the matrix, which considerably impedes the passage of substances like gases, oils, and greases. Alternatively, they can be incorporated in coatings to perform a UV screening function, with the significant advantage that, being smaller than the wavelength of visible light, the coating remains transparent. The unique properties arise mainly from the aspect ratio - a single gram has a surface area of more than 750 m^. Some automobile companies have been testing compounds: GM has been working with Montell on a thermoplastic olefin elastomer with 5% smectite clay from Southern Clay Products, giving stiffness equivalent to 2 5-35% talc and Dow Automotive Group has been working with Magna. Nano-particles may also play a significant role in development of 'hard' coatings on plastics glazing for automobiles. Incorporation of somewhat larger particles provides another interesting technology being developed by Bayer, in the field of polyurethanes. The company, with its machinery subsidiary Hennecke, has developed a new mixing head which enables expanded graphite in the form of millimetre-sized particles to be processed as a filler for rigid foams. The graphite particles must not be physically damaged during mixing, even under high pressure, and also have to be uniformly distributed in the foam, which is a real challenge to chemical engineering. A process has been developed and patented which could make it possible to produce flame-retardant polyurethane rigid foams without the use of halogenated additives. This new development could be especially important in the thermal insulation of buildings. Nano-scale hollow carbon tubes thousands of times smaller in diameter than carbon fibres are also of interest. Compounder RTP has commercialized a range of Nanotube Compounds (NTCs) that deliver uniform and precise surface resistivity throughout a spectrum from strong electrostatic discharge (ESD) to strong anti-static (typically ranging from 10^ to 10"^ ^/sq). To achieve similar levels of conductivity using conventional additives such as carbon fibre or carbon black would require higher loadings that may affect physical properties such as strength and toughness/impact, processing, and surface finish. 4.5.7 Processing

nano-composites

The key components of polymeric nano-composites are water-swellable synthetic and natural layered silicates such as montmorillonites (the main


33

fraction of the clay mineral bentonite). These are commonly used for a number of other purposes and are commercially available in different types. The high aspect ratio of the layers strongly influences the properties of the host polymer and polypropylene provides one of the most interesting of these. To obtain the value of the properties, the layers have to be separated (called 'exfoliation'). For addition to a polymer melt the layered silicates are usually swollen, making exfoliation much easier than with dry silicates. The swelling agent has to have a boiling point higher than the melting temperature of the polymer but noticeably lower than the permissible melt processing temperature. In the case of polypropylene, swelling agents with boiling points between 180 and 200°C have been used. The consistency of the mixture of silicate and swelling agent depends on the silicate/swelling agent relationship, the 'swellability' of the silicate, the type of swelling agent, and the temperature, and can range from liquid through slurry to a crumbly paste. The are two basic ways of making polymer/clay hybrids. Direct polymerization in the presence of clay platelets has been used successfully for polyamides and for epoxy and other resins. But, at a less exotic and more flexible level, compounding offers an economic way of modifying polypropylene - in theory - and there has been some active development of processes to produce polypropylene/clay hybrids by melt mixing. To achieve the high level of dispersion required, slurry processes are being developed both as a means of opening up the fine clay particles and separating the plate-like layers, and also to incorporate sub-microscopic particles of calcium carbonate into polypropylene. The filler is introduced as a slurry in 2 5% water at the start of the process and with polypropylene in powder form. During plasticizing, the water content of the slurry vaporizes and is vented by the usual degassing aperture. Researchers at Dresden University and at Elf Atochem's research and development centre at Serquigny, France, have been working on modification of a standard Werner and Pfleiderer in which, rather than adding the filler to the melt, the filler is brought in at the beginning of the process, as a slurry in water, and mixed with a powdered form of polypropylene.

Table 4.4 Properties of a nano-composite PAG compound, compared with conventional reinforcement

Tensile strength (psi) Flexural modulus (1000 psi) Notched Izod impact strength Heat distortion temperature (°C) Specific gravity Source: RTP Co

Unfilled

3-5% organo-clay

30% mineral

30% glass fibre

7250 120 1.2 66 1.13

11 800 500 1.2 110 1.14

8000 650 1.6 120 1.36

23 000 1100 1.8 194 1.35

34


Table 4.5 Polypropylene nano-composite made by a slurry process compared with conventional compounds Unit

Reference (pure polypropylene)

Conventional compound

Slurry process

Chalk

wt%

().()

24.9

22.5

Flexural modulus

MPa

992

1428

1379

Elongation at break

%

639

125

594

Unnotched Charpy impact, 23°C Notched Charpy impact, 2 3°C

kjm-^

NB

140 1()0%B

kjm-^

13.7

10.3

160 40% B 60% NB 50.0

Multiaxial impact total energy, 3 mm. 4.3ms-^23°C

J

80 (ductile)

35 (semi-ductile)

74 (ductile)

Melt flow index, 23()°C, 5 kg

g(l()min)-i

10.5

4.0

4.5

Sourcc: Elf Atochcin

RTP has developed a technology for incorporating organo-clay hybrids into extruded nylon sheet or film via the compounding process. This form of lightweight composite requires only a loading of the order of 2-8% to exhibit properties equivalent to or better than typical mineral-filled compounds at 0 30% loadings. Much of the original wôrk on nano-composites came out of the Toyota Central Research Laboratories in the 198()s and the original licensee vâs Ube Industries, which has since been pursuing work on nylon 6 compounds. Other Japanese researchers have been concentrating their efforts on methods for the production of nano-sized carbon and fullerene tubes. These are tiny hollow fibres of carbon atoms arranged in rolled hexagonal lattices. Discovered by NEC's Sumio Ijima in 1991, they are creating interest in the plastics and automotive sector as conductive reinforcements for plastics, with possible large-scale use in automotive bodywork panels. Carbon nano-tubes are reported to be effective in assisting electrostatic painting at as low as 2% addition, and they also offer a better surface finish. But they are still expensive. Resin masterbatches containing 15-20% loadings are around US$44 kg~^ but producers expect these prices levels to fall with increasing use. GE Plastics reports that several automobile manufacturers in various parts of the world are running tests on filled mouldings for body panels, with the first commercial applications expected in 2 0 0 1 . Hyperion Catalysis International has introduced a range of graphite nano-tubes, under the trade name Fibril, for conductive applications in plastics.


35

Table 4.6 Physical properties of nano-tubes in polycarbonate Property Tensile strength (kpsi) Tensile modulus (kpsi) Elongation (%) Flexural strength (kpsi) Flexural modulus (kpsi) Izod impact un-notched (ft lb in~^) Heat distortion temperature at 264 psi (°C) Shrinkage (%) Specific gravity

Base polymer

3.5% nano-tubes

5.0% nano-tubes

10.0

8.7 364 24 13.4 372 NB 129 0.5 1.21

8.9 399 30 14.5 401 26.5 124 0.5 1.25

-

125 14.0 340 NB 129 0.5 1.20

Source: Hyperion Catalysts

4.6 Commercial Trends

It is virtually impossible to place a value on the world fillers market, but specific sectors involving speciality types with higher economic potential have been surveyed. The best documentation comes from the US market, and it can be expected that the markets in Europe and Japan/Asia will be about the same size. US consumption of fine particle-sized calcium carbonates (which improve brightness and reduce absorption in a variety of polymer matrices) is expected to reach about 176 500 tonnes by 2003, valued at US$38.6 million. Use of fineparticle kaolin and other clay-based fillers in plastics will total 5 7 600 tonnes, valued at US$21.7 million, and compounders and resin producers are expected to increase use of fine-particle and surface-treated alumina trihydrate by 6.2% per year, from about 30 800 tonnes in 1998 to 41 700 tonnes by 2003. Antimony oxide fillers are now seen not only as useful flame retardants but also as providing valuable synergistic abilities (acting as potential replacements for titanium dioxide), while also controlling opacity, colour, and tone in various resin systems. MH fillers continue to gain market acceptance as alternatives to ATH and halogen-based flame-retardant systems. There is renewed interest in halogen-free formulations with smoke-suppressing properties and thermal stability, driving an annual growth rate of 6.1 % over the next five years. The global market for speciality silicas, including precipitated silica, silica gel, fumed silica, and colloidal silica, is estimated (by Kline, Belgium) at a value of US$1.7 billion. Demand is fairly evenly divided between Western Europe (34%), Asia/Pacific (32%), and North America (2 7%), with other regions accounting for approximately 7%. The market is expected to grow at a rate of about 4% a year in real terms, excluding significant inflation, to exceed US$2 billion by 2002. Precipitated silica is expected to grow at nearly 5% a year, because of expanding manufacture of rubber footwear in Asia, as well as emerging growth in 'green tyre' applications. Fumed silica, which is heavily dependent on silicone rubber, has an expected growth rate of more than 5% a year. The largest producers, Degussa, PPR, and Rhone-Poulenc, account for about two-thirds of global capacity for precipitated silica.


CHAPTER 5 Modifying Specific Properties: Mechanical Properties - Reinforcements The reinforcement used with plastics, both thermosetting resins and thermoplastics, is usually a fibre or filament, used either on its own, or in mixtures. Non-fibrous materials can also be used in some cases. Reinforcing fillers are also used, including glass flakes, mica platelets, fibrous and finely divided minerals, and hollow and solid glass microspheres. Table 5.1 At a glance: fibre reinforcements Function

Fibrous materials offer good reinforcement to plastics, depending on the strength and length of the fibre and the effectiveness of the fibre/matrix bond. Being fibrous, however, the main constraint is processability. For injection moulding and reaction injection moulding of polyurethanes, fibres must be very short, limiting the effectiveness of the reinforcement. Long and continuous fibres can be used in thermoset compression moulding, but these may require some form of preforming. Surface treatment of reinforcing fibre influences adhesion properties; coupling agents can improve properties with materials such as polypropylene.

Properties affected

Tensile strength, elasticity, dimensional stability under heat, wear properties; carbon and metal fibres/filaments/whiskers also give anti-static/electrically conductive properties.


Glass fibre (overwhelmingly the most important). High-performance fibres (aramid, boron, carbon) are mainly of interest for thermosetting resin composites: growing use of high-performance thermoplastics will extend use of fibres.

Disadvantages

Adaptation of a two-dimensional fibrous reinforcement to a three-dimensional moulded component.

New developments

Long-fibre injection moulding compounds; improved surface treatment/coupling agents; use of high-performance fibres in forms more suitable for injection moulded thermoplastics.

The method by which the compound will be moulded or shaped naturally dictates the form of reinforcement. In thermoplastic compounds (which will be predominantly injection moulded), short-length fibre or particulate reinforcement is used, but there has been important development of so-called Tong'-fibre compounds, with a higher ratio of reinforcement to resin matrix and a longer

38


length of fibre, delivering to the compound more of the basic strength of the reinforcement. In thermosetting compounds (which are in various forms for moulding by compression or by a modified form of injection), fibre lengths can be much higher. These are known as bulk moulding compounds (BMCs) or dough moulding compounds (DMCs). A third form of both thermoplastics and thermosetting compounds takes the form of a sheet material that is press-moulded or stamped. It comprises a mat of reinforcement (which can include non-woven or woven structures, with chopped or continuous filament reinforcement) impregnated with the thermoplastic or thermosetting resin. The mechanical properties of the compound are largely dictated by the reinforcement and its positioning (or orientation): a high reinforcement content

Figure 5.1. Polypropylene is reinforced with chemically coupled glass fibre for injection moulding this Whirlpool washing machine tub, giving high performance for low cost. (Photograph: Ticona)

39

Modifying Specific Properties: Mechanical Properties - Reinforcements

produces high tensile strength, but not necessarily high rigidity. As resin content increases, so does resistance of the moulding to chemical attack and weathering. The resin/reinforcement ratio is therefore one of the most important factors determining the properties of a reinforced plastics structure.

5.1 Fibres: The Basic Properties

Fibrous materials act to reinforce a matrix material by transferring the stress under an applied load from the weaker matrix to the much stronger fibre. Polymers provide valuable and versatile materials for use as matrices. For an efficient composite under stress, the elongation of the fibre must be less and its stiffness modulus higher than that of the matrix. Stress transfer along the all-important fibre/matrix interface can be improved by use of sizings, binders, or special coupling agents. The diameter of the fibre also plays an important part in maximizing stress transfer. Smaller diameters give a greater surface area of fibre per unit weight, to aid stress transfer in a given reinforcement context. Glass is predominantly the most important and widely used fibre in reinforced plastics. Other fibres are natural (cotton, sisal, jute), synthetic (nylon, polyester, acetate, rayon), or organic and inorganic high-performance fibres (aramid, boron, carbon/graphite). Fibres are used mainly in the form of short or long chopped filaments/strands, mats made of random chopped strands, or woven fabrics of varying density. Woven and non-woven fabrics can be used to improve surface qualities such as appearance, impact resistance, abrasion, and chemical resistance. To improve distribution and orientation of fibres in a three-dimensional moulding, there has been considerable development of preforming techniques, and machine-made three-dimensional arrangements of fibre, which offer better 'drape' in a mould. When more than one fibre is used, the composite is termed a hybrid. Table 5.2 A quick guide to the relative properties of fibres Property

Aramid

Carbon

Glass

Tensile strength Tensile modulus Compressive strength Compressive modulus Flexural strength Flexural modulus Impact strength Interlaminar shear strength In-plane shear strength Density Tension-tension fatigue

0 0

0

0 ++ 0

++ ++ ++ ++ ++ ++ 0 ++

0 ++ 0

++ 0 ++

Key: ++ = best,

0 = average,

-

0

-

- = poorest.

0 0 0 ++ ++

40


Table S.3 Comparison of commonly used reinforcing fibres Fibre/grade

Density (gcm-^)

Tensile strength (MPa)

Flexural modulus (GPa)

Specific modulus (Mm)

Carbon HT Carbon IM Carbon HM Carbon UHM Aramid LM Aramid HM Aramid UHM E-glass R-glass Quartz glass Aluminium Titanium Steel (bulk) Steel (extruded) Steel(stainless)

1.8 1.8 1.8 2.0 1.45 1.45 1.47 2.5 2.5 2.2 2.8 4.5 7.8 7.8 7.9

3500 5300 3500 2000 3600 3100 3400 2400 3450 3700 400 930 620 2410 1450

160-2 70 270-325 325-440 440+ 60 120 180 69 86 69 72 110 207 207 197

90-150 150-180 180-240 200+ 40 80 120 27 34 31 26 24 26 26 25

5.2 Types of Reinforcing Fibre

5.2.7 Aramid fibres

These have a low density/high tensile strength ratio and are produced by spinning a liquid crystal polymer, usually as filament yarns, rovings, or chopped fibres. They are produced from an aromatic polyamide and have a characteristic bright golden yellow colour. The fibre has high strength and relatively low density, with very high specific tensile strength. All grades are particularly good in resistance to high impact; lower modulus grades are widely used in antiballistic applications. The compressive strength, however, is unexceptional and only equivalent to that of glass. Aramids represent a large part of the world market for high-performance fibres, which totalled some 40 000 tonnes in 1990, with a growth rate estimated at 10% annually. Applications are no longer limited to the very high-performance sector; in fact, a large part of the business of aramid fibres is in combinations with other reinforcements, giving precise properties precisely where they are required. To date, however, the majority of applications have been in fairly large structures with thermosetting resins (as in aerospace and transport). Outside the thermosetting resins, aramid fibre is also used in speciality tyres and, as commingled yarns, in production of thermoplastic composites, using a polymer melt, solution, or powder, or a hybrid yarn or fabric, suitable for high drapability and coping with very sharp fillet radii.


41

An interesting development for thermoplastics is a technique for pulping or fibrillation that greatly increases the surface area of short-length fibres of paraaramid, and renders them suitable for reinforcement of plastics and elastomers. While a typical staple fibre will have a surface area of about 0.1 m^ g~^, the new compounding process increases this to 7-9 m^ g~^, so increasing the area available for adhesion to the matrix polymer. The bond achieved will improve properties of the compound, particularly abrasion resistance. High strength/low weight, mechanical stiffness, and resistance to thermal and chemical attack are other advantages. The development has been commercialized (by DuPont) as a masterbatch for elastomers (for power transmission belting, hose, tyre bead and tread areas, bearings, packings, and seals) and for thermoplastics (for a wide variety of applications). A similar development has been reported by Akzo. Techniques for production of three-dimensional structures of high-tenacity aramid fibre have also been developed, offering excellent fatigue resistance to abrasion, flexure, and stretching. One such system is on a wire frame basis, with mechanized frame building, and is proposed as a reinforcement for concrete pillars and other structures. As well as the strength of the fibre, this application exploits the high chemical resistance of aramid to acids, alkalis, and cement. 5.2.2 Carbon or graphite fibres

These are widely used in high-performance applications, well repaying their high cost. The fibre ranges from amorphous carbon to crystalline graphite, depending on manufacturing method. Stiffness or Young's modulus can range from less than glass to three times that of steel; the most widely used types have a modulus of 2 0 7 - 2 6 8 GPa. The fibre is available as short-length fibres, twisted and non-twisted yarns, continuous filament, and tows. Carbon/graphite fibre is produced by controlled oxidization and carbonization of precursors in fibre form. The usual precursors are cellulose, polyacrylonitrile (PAN), lignin, and pitch, of which PAN is most commonly used as it has a high carbon content. Treatment at temperatures up to 2 600°C produces a high-strength fibre and increasing the temperature to 3000°C produces a high-modulus graphite fibre. This chemically changes the fibre, yielding high strength/weight, high stiffness/ weight properties obtained through oxidation, carbonisation, and graphitization. Successive surface treatment and sizing improves bonding and ease of handling. The resulting fibre is stronger than steel, lighter than aluminium, and stiffer than titanium. Fibre can also be produced from a pitch precursor, but the elongation of these fibres tends to be low. The usual grades of carbon fibre (indicated by their initials) are high strain (HS), high strength (HT), and intermediate grades, such as intermediate modulus (IM). The most common form is a high-tensile-strength fibre, produced by most suppliers. Carbon fibres have the highest specific stiffness and very high strength in both tension and compression. Their impact strength is lower than that of glass or aramid fibres, and carbon is often combined with these to form hybrid materials.

42


Table 5.4 Typical properties of continuous pitch-based carbon fibres (based on BP Amoco Thornel grades)

Tensile strength (GPa) Tensile modulus (GPa) Density (gem'^) Elongation at break (%) Filament diameter (|im) Carbon assay (%) Surface area (m- g~^) Electrical resistivity ()i ohm-m) Thermal conductivity (W m"^ K~^) CTEat2rC(ppm°C"M

Carbon

Graphite

Ultra-high conductivity graphite

1.38-2.07 159-3 70 1.90-2.0 0.9-0.5 11-10 97+-99+ 0.70-0.35 13-8.5 22-120 -().60to-1.3

2.10-2.41 517-82 7 2.00-2.17 0.4-0.3 10 99 + 0.3 5-0.40 7.0-2.2 18 5-640 -l.14to-l.45

2.34-3.10 896-965 2.17-2.20 0.3 10 99 + 0.40 1.2-1.3 800-1000 -1.45

Source: BPAmoco

Table 5.5 Typical properties of continuous PAN-based carbon fibres (based on BP Amoco Thornel grades)

Tensile strength (GPa) Tensile modulus (GPa) Density (gem ^) Elongation at break (%) Filament diameter ().im) Carbon assay (%) Surface area (m- g ') Electrical resistivity (|.i ohm-m) Thermal conductivity (Wm 'K ') C T E a t 2 r C ( p p m ° C ')

T-3()()^'

T-3()()C

T-65()/35''

T65()/35

3.75 231 1.76 1.4 7.0 92 0.45 18 8 -0.60

3.75 231 1.76 1.4 7.0 92 0.45 18 8 -0.60

4.28 255 1.77 1.7 6.8 94 0.50 15 14 -0.60

4.28 255 1.77 1.7 6.8 94 0.50 15 14 -0.60

'' Development grades. Source: BPAmoco

Carbon fibre can be supplied as continuous or cliopped fibre. Continuous fibre can be combined witli virtually all thermoset and thermoplastic resin systems and is used for weaving, braiding, pre-preg manufacture, and filament winding. Chopped fibres can be used in moulding compounds for compression and injection, giving parts with high resistance to corrosion, creep, and fatigue, with high strength and stiffness. In thermoplastics, carbon fibre is particularly used in reinforcement of nylon, where a 30% (by weight) fibre content will increase fiexural strength by about three times, and fiexural stiffness may be increased by a factor of seven. Electrical properties, friction behaviour, and wear resistance may also be improved. Electrical applications fall into two categories: to impart conductivity, to prevent build-up of electrostatic discharge (which may cause short circuits, or


43

explosions when handling hazardous materials); and to screen components from electromagnetic interference. Frictional and wear properties are very good in comparison with nonreinforced or glass fibre-reinforced compounds. Non-reinforced PA 6 has static and dynamic friction coefficients about 2 5 and 40% higher than those of a carbon-reinforced PA 6, while the abrasion factor is 10 times higher. Combined with the higher thermal conductivity of carbon-reinforced compounds, this produces higher pv values (p = bearing pressure, v = sliding velocity), which are a measure of the heat generated by parts sliding in contact with each other. 5.23 Glass fibre

This is the most widely used reinforcing material, both for thermosetting and thermoplastic composites. It has high tensile strength combined with low extensibility (3.5%), giving exceptional tensile, compression, and impact properties, with a relatively high modulus of elasticity and good bend strength. It also has high-temperature resistance and low moisture pick-up, giving good dimensional stability and weather resistance. Finally, low moisture absorption makes it possible to produce mouldings with good electrical properties that do not deteriorate, even under adverse weather conditions. Glass fibre also exhibits virtually elastic behaviour. It will stretch uniformly under stress to its breaking point without yielding and, on removal of the tensile load short of breaking point, the fibre will return to its original length. This lack of hysteresis (which is not found in conventional metal and organic fibres), together with high mechanical strength, makes it possible for glass fibre to store and release large amounts of energy without loss. This capability, together with dynamic fatigue resistance, if protected from abrasion, has been put to effective use in springs for automobiles, trucks, trailers, and furniture. The fibre is produced by blending together the raw materials (sand, kaolin, limestone, and colemanite) and feeding the mix into a batch oven heated to about 16()()°C. The liquid glass fiows into channels and the fibres are drawn through electrically heated bushings, each of which can produce thousands of filaments of 10-24 |im in diameter. The filaments are coated with size to ensure cohesion and protect them from abrasion (also providing properties essential for subsequent processing operations). Finally, the wet fibre is dried and processed into its finished form. There are several types of glass: • •

A-glass (for 'alkali') is the original type of glass fibre. This is a high-alkalicontent material, with a chemical composition similar to that of window glass. It has been largely replaced now by other forms. E-glass (for 'electrical') is a calcium alumino-borosilicate composition, of low alkali content and stronger than A-glass. This is regarded as the pioneer type and is the type usually specified for reinforcement purposes, unless operating stresses are relatively low. It has good tensile and

44


• • •

compressive strength and stiffness, good electrical properties, and relatively low cost, but impact resistance is relatively poor. C-glass (for 'chemical') is a grade with improved resistance to chemical attack, mainly used for surface tissue. D-glass has particularly good dielectric characteristics and is used mainly in the electronics industry. R- and S-glasses have a different chemical composition, giving a higher tensile strength and modulus, and better wet strength retention. They were developed to meet the demand for higher technical performance from the aerospace and defence industries. They have smaller filament diameters, which increase the surface area so improving interlaminar strength and wet-out properties. S-glass is produced in the USA and R-glass in Europe; the properties are broadly similar and the density is the same as that of E-glass.

Table ?.6 Main properties of glass fibre Unit

E-glass

R-glass

Mechanical properties (new, untreated filament) Ultimate tensile strength MPa lO^psi Flexural modulus GPa lO^psi Elongation at break % Poisson's ratio

493

638

10.5 4.4-4.5 0.22

12.7 5.2

General properties Specific gravity (in bulk) Specific gravity (in filaments) Mohs hardness

2.60-2.82 2.50-2.59 6.5

2.55 2.53

2.80

2.30

1.550-1.566 Opaque

1.541

Thermal properties (glass in bulk) Coefficient of thermal expansion

10-

Optical properties Refractive index (at 2 5°C) UV transmission (at 2 5°C) Electrical properties DC volume resistivity (logi Q 150-400°C) Dielectric constant at 10^ Hz (30 mm diameter disc 3 mm thick) Chemical properties Alkalinity (Na20 equivalent) Solvent resistance Alkali resistance Acid resistance

ohm.cm ohm.cm

17.7-10.4 6.5-7.0

6.0-8.1

% % % %

0.3 Good Good Except hydrofluoric

0.4 Good Good Except hydrofluoric


45

5.2.3.1 E-CR glass The development of the different types of glass fibre has been in response to demand from specific markets, and the latest call is for improvement in long-term resistance to chemicals. The whole sector termed *anti-corrosion' is now one of the most important applications for glass fibre-reinforced materials, embracing the industries of marine products, chemicals, pulp and paper, and food manufacture as well as water treatment, anti-pollution, power plant desulphurisation, and many other important sectors dealing with environmental protection. E-glass fibre is widely used for its high strength/cost ratio, but glass generally is not totally inert in chemically corrosive environments and to meet many design codes requiring a corrosion barrier or liner to be incorporated in a laminate, to protect the structural integrity of the glass-reinforced substrate, a resin-rich layer supported by C-glass, or an organic fibre veil such as polyester or acryfic, has been used, to act as an impermeable protective layer. However,

Table 5.7 Glass fibre: comparison of E- and E-CR glass

Average glass composition (indicative only) (%) SiOi AI2O5 B2O3 CaO MgO Na20 + K20 Fe203 ZnO Ti02 Properties Tensile strength (MN m^) -virgin fibre 23°C -virgin fibre 100°C -virgin fibre 196°C E-modulus of elasticity (GN m^) Density (gem"^) Refractive index Coefficient of linear thermal expansion {°C~^) Dielectric constant, 23°C - 6 0 Hz - 1 0 ^ Hz Loss tangent, 23°C - 6 0 Hz - 1 0 ^ Hz Volume resistivity, 2 3°C and 500 V DC (^/cm) Dielectric strength (kV mm)

E-glass

E-CR glass

52-56 12-16 5-11 15-2 5 0-5 0.5-2.0 0.05-0.5

52-56 10-15

-

0-1.0

18-25 0-5 0.5-2.0 0.05-0.5 2-5 0-3.0

3331 3185 5320 72.5 2.52-2.62 1.556 5.0 10-^

3330 3240 5280 72.5 2.70-2.72 1.576 5.9 10-^

6.4 6.2

7.1 7.0

0.003 0.004 1014 9.80

0.004 0.003 1014 9.96

-

46


sustained stresses and corrosive attack by strong acids or alkalis act synergistically, gradually deteriorating E-glass fibres. E-CR glass (for 'corrosion resistant') was developed to cater for this market. It has significantly better resistance to acid corrosion than E-glass, although its composition does not differ greatly, the main difference being that it does not contain boron oxide. It is listed for improved resistance to acidic corrosion in ASTM D5 78 and ISO 2078, and under DIN 12 59 is classified as aluminium limesilicate glass that is particularly designed for reinforcement of plastics submitted to acidic environments. Grades of this glass have Lloyds approval and are certified to meet the Boeing BMS-8-79 specification. The sUghtly higher density of E-CR glass is not a serious factor, as the diameter ranges are within the tolerances of traditional E-glasses. A slightly higher refractive index may give E-CR glass laminates a slightly more yellowish tint, which is barely distinguishable. Tests for laminate properties indicate that the moduli and stiffness of laminates made with each type of glass are identical. Tensile, flexural, and shear strengths are generally equal or slightly higher with E-CR. Long-term behaviour (tension creep in air) is identical. 5.2.3.2 Other developments Among other recent developments are new types of glass fibre roving designed for use in sheet moulding compound (SMC) and giving both good processing characteristics and mechanical strength. These are a medium-hard/mediumsoluble reinforcement with high integrity for SMC automotive and industrial applications where the mouldings are either pigmented or painted. They wet-out quickly and thoroughly, and offer good composite mechanical properties, especially tensile and flexural strength. New glass fibre-reinforcement products for use in fibre-directed preform processes are another focus of development, designed specifically for liquid composite moulding applications such as resin transfer moulding with thermoset polyesters. A new E-glass roving gives fast wet-out with polyester, vinyl ester, epoxy, phenoUc, urethane, and furan resin systems, due to low sizing content. Low loss on ignition means that there is not an excessive amount of sizing to be broken down by the styrene in the resin. Owens Coming's Miraflex fibre is two different forms of glass fibre fused together in a single filament, resisting typical textile processes such as carding and needling: the fibres are random twisted, flexible, soft-touch, and virtually itch free. Also working on mixtures, Vetrotex CertainTeed has developed Twintex - a commingled reinforcement of unidirectional glass fibre rovings and polypropylene filaments. PPG Industries has introduced MatVantage - a continuous strand mat for pultrusion, offering unique laminate characteristics - and new low-catenary conventional rovings plus three new chopped strands for thermoplastics. Type 2016 roving is for direct-draw filament winding for oilfield composite pipe and

Modifying Specific Properties: Mechanical Properties - Reinforcements 4^7

other corrosion applications, Type 5530 roving is for Class A automotive painted parts, pigmented applications, and others, and GPN chopped strand mat is for composites with general-purpose polyesters. A glass reinforcement said to offer superior mechanical properties in compounding polypropylene, enhancing the performance of both coupled and uncoupled formulations, is Star Stran from SchuUer Mats and Reinforcements. It is a high-strand integrity product with good fibre feed and handling characteristics, in 3.175 and 4.76 mm chopped lengths. 5.2.3.3 Forms of glass fibre The form in which glass fibre can be used for reinforcement is of course largely dictated by the moulding process. For thermoplastics, where the main process is injection moulding, the glass is used in short (about 0.3 mm) fibre lengths, which will pass through the nozzle of the machine without being too severely damaged in the process. There has been much development, therefore, of treatments to the surface of the glass fibre and improvement of the fibre/polymer interface, to provide a degree of lubrication and prevent damage to the fibre. The process of injection into a closed mould also means that the orientation of the fibre (which essentially provides the strength) is difficult to control, and there has also been much work on mould design to encourage flow and orientation in desirable directions. An important development in recent years has been the introduction of thermoplastics compounds with longer fibre lengths (called 'long-fibre' compounds), in which the fibre and resin are combined in a different manner, giving higher lubrication and allowing higher fibre/resin ratios to be employed. These compounds are described in more detail below. For reinforcement of thermosetting plastics (where the moulding processes are manual with an open mould, various forms of compression/contact moulding, or actual winding of reinforcement onto a former), glass fibre is used in continuous and discontinuous forms, as roving, bonded mats, or a wide variety of woven or knitted textile forms. An increasing amount of glass fibre is suppUed as continuous roving that is chopped into small lengths in resin mixing and spraying units. Using roving rather than continuous strand mat has an important economic benefit because the glass costs less, and there is less waste. An important area of development is how best to preform the fibre reinforcement, and a key advantage of the fibre-directed preform process is the ability to change reinforcement strand geometry simply by changing the input: impact strength increases as the roving strand geometry becomes more coarse, while tensile and fiexural strengths are only minimally affected. Another area of current development is design of 'three-dimensionaF fabrics, which will provide bulk and/or lend themselves easily to the shape of a required moulding without the need for expensive preparation stages. 5.2.3.4 Chopped!milled products Continuous-strand/high-modulus fibre is chopped to 3.2-50 mm (|of an inch to 2 inches) or milled/ground into shorter lengths for use in moulded composite

48


parts; pre-preg products are a standard grade modified with (typically) an epoxy resin curing at 120°C, as unidirectional pre-preg rolls. Milled fibres are produced by hammer milling, giving lower stiff'ness and strength than chopped fibre, but controUing heat distortion and improving surface finish. They are normally used in liquid component mixing/ injection processes such as reinforced reaction injection moulding (RRIM) of polyurethanes. Because of fibre length and Ughtness, they can cause dust and irritation in the production shop and should only be handled in closed systems. Glass flakes are used in resin-based coatings, to reduce permeability to moisture, vapours, and solvents; they have also been used in reaction moulded polyurethanes to improve surface finish. 5.2.4 Polyester fibre

This offers a low-density, high-tenacity fibre with good impact resistance but low modulus. It is used in areas where high stiffness is not required, but where low cost, low weight, and high impact or abrasion resistance are important. Polyester is used mainly in surface tissue for laminates, but also offers high impact resistance, good chemical resistance, and good abrasion resistance. The advantages of polyester are that it does not need binders that have to be dissolved in the resin matrix, it has high conformability, and excellent strength/ weight ratio. As a surfacing material, the fibre is easy to sand. Fabrics are half the weight of equivalent glass material, with excellent energy absorption, chemical resistance, and dielectric/electrical insulating properties. They are internationally certified by Lloyd's Register of Shipping and the American Bureau ofShipping. Polyester fibre does not specifically feature in thermoplastics compounds at present, but there has been some interesting work reported (by DSM), compatibilizing thermoplastic polyesters to accept polyester fibre as a reinforcement, which might greatly simplify the recycUng of fabric-covered automobile interior panels (if they were moulded in polyester in the first place). 5.2.5 Polyethylene

fibre

Recent work has produced a very low-density fibre from ultrahigh-molecularweight polyethylene (UHMW PE), which offers strengths that (for the density of the fibre) are among the highest to be found anywhere. It is made up of aligned polymer chains with high elongation and good impact resistance. But, although the fibre has remarkable properties, its low modulus and ultimate tensile strength and the relatively high cost of treating the fibre surface to improve the fibre/matrix bond mean that PE fibre is not often used in reinforced plastics structures. Performance figures show that specific gravity is low, at 0.97 (aramid is 1.44, polyester 1.38). The fibre is 35% stronger than aramid and has a high energy/ break ratio, giving remarkable ballistic properties. It exhibits impact energy


49

absorption in composites 20 times that of glass, aramid, and graphite and also has excellent vibration damping properties. The melting point is 147°C. Possible applications for composites include boat hulls, sports equipment, radomes, structural components, pressure vessels, and in aerospace and industrial applications. 5.2.6 Hybrid fibres

An almost unlimited field of possibilities opens up with the combination of different fibres as 'hybrids', which with an appropriate resin matrix can most closely fill a specific closely identified application. In most cases, however, this is a matter for specialists, backed by an exhaustive database of fibre forms and properties. A typical off-the-shelf hybrid might be a boron/graphite pre-preg, composed of small-diameter graphite fibres dispersed between 76 and 100 [iui diameter boron fibres, in an epoxy matrix, to 70-80% total fibre content. This is claimed to achieve a hybrid effect with properties superior to composites based on either fibre. The flexural stiffness and strength is twice that of carbon and 40% higher than that of boron. Interlaminar shear strength also exceeds that of carbon and boron. The resin matrix can be a toughened epoxy or a polyimide.

5.3 Other Fibres

Other reinforcing fibres, of less commercial importance, include: asbestos, boron, and nylon fibres. 5.3.7 Asbestos fibre

This has been used in the past with both reinforced thermosets and thermoplastics, offering good rigidity, chemical resistance, and particularly fire resistance. Its use has, of course, ceased following discoveries of the health hazards associated with asbestos fibre. It may, however, be encountered in recovery of old mouldings, and advice should be sought immediately on the precautions necessary in handling it. 53.2 Boron fibre

This is of very high cost and is used with epoxy resins in specialized aerospace applications. 533

Nylon fibre

This may be used with epoxy resins, for high impact, abrasion resistance, and chemical resistance. In moulding compounds with thermoplastics matrices it has very widespread use.

50


5.4 Natural Fibres

Natural fibres such as jute and sisal are inexpensive and readily available. Jute is used particularly in developing countries in cloth and yarn. Sisal fibre may be used in some DMCs, although more with phenolic matrices than with polyesters orepoxies. Good fibre strength and rigidity, plus low cost and environmental advantages encourage the use of vegetable bast and hard fibres such as flax, hemp, jute, ramie, or sisal for reinforcement of thermoplastics. Production of large and low/ medium stressed components in polypropylene reinforced with flax mat is gaining in popularity. With fight but extremely rigid parts, flax fibre-reinforced plastics could compete with glass-reinforced materials for applications such as automobile interiors, but the possibilities of this material in highly stressed structural components depend of the properties of the composite under dynamic stress. However, there is virtually no information yet available on this. The normal test for dynamic evaluation of materials or components is the Wohler fatigue test, to characterize fatigue behaviour. Hysteresis measurements are carried out on flax and glass mat-reinforced polypropylene, with a needlepunched flax mat using green and retted fibres to make plates with a quasiisotropic composite structure, and with treatment by a coupling agent. Green and retted fibres differ in the degree of fibre digestion and physical data. Green flax fibres are stronger and much coarser (fineness > 4 tex), but their modulus of elasticity is lower than that of retted fibres. Retted fibre has intensive fibre digestion, due to the action of moisture during retting, producing fine fibres with a high modulus and low strength as a result of decomposition during retting. Green flax has less intensive fibre degradation due to only brief exposure to moisture, producing a coarser fibre bundle with high strength and low modulus due to good elongation at break. Unlike glass fibres, which have a round section, industrial flax fibres are made up of numerous individual fibres or fibrils bonded together by vegetable substances and have a rough surface, meaning that they can already be regarded as composite materials. Flax fibres have a lower strength and composites did not achieve the tensile strength values of glass mat-reinforced polypropylene with the same fibre content. But high values are determined for modulus of elasticity. High-quality green flax has a better reinforcing effect than retted flax: a content of some 40% by weight produces tensile stress values in the range of those for glass matreinforced polypropylene at a content of 30%. Silane-treated fibres at 30% fibre content nearly reach the strengths and stiffnesses of 40% flax/polypropylene composites. The improvement in fibre matrix adhesion is found in both green flax and retted flax-reinforced compounds. Polypropylene compounds reinforced with flax and glass mat, at comparable fibre contents, have similar fatigue strengths when exposed to dynamic repeated tensile stresses. The flax fibre composites are characterized by their high material damping, which is attributable to the specific properties of flax fibres. Tests at


51

microscopic level show that it is usually microcracks, tending to run transverse to the stress direction, which are responsible for the failure of fibre composites. Increasing the fibre content and improving the fibre/matrix adhesion improves fatigue strength.

5.5 Forms of Reinforcement

The available forms of reinforcement broadly follow terminology and technology 'borrowed' from the textile industry. The basic forms described above for glass are used, as appropriate, with all types of fibre, including hybrid mixtures. There are also thermoplastic equivalents, such as high-performance carbon/ PEEK tapes, which are 'pre-pregs' in which continuous filament and matrix have been closely combined by a form of pultrusion process and require only placing in position (often by winding or layering) and heating, to fuse the thermoplastic matrix. Technology extending the principle to continuous filament and polypropylene matrices has been developed more recently. A further variation is to bring both the reinforcement and thermoplastic matrix together in the form of fibres, which are then readily combined (described as commingled), giving an improved interfacial bond. An advanced form of this is based on biaxial thermoplastics in the form of fibres (PA, PBT, PET, PP/PPS, PEI, APC-2, or PSUl), with carbon, aramid, and glass pre-impregnated tape. The pre-preg is unidirectional and interlaced in a biaxial form in continuous lengths. The manufacturers claim that an unprecedented width (up to 3.04 m) is possible. Overall, the material maintains and improves the properties of unidirectional cross-ply laminates, giving the benefit of unidirectional tape in larger and more easily processed formats. With very good drape characteristics, it is claimed to be the first real alternative to the compromise often necessary with woven composites. Parallel to thermosetting SMCs and BMCs are thermoplastic moulding compounds in sheet form, known as glass mat thermoplastics (GMTs), and compounded into standard granules for injection moulding and extrusion. Most thermoplastics are theoretically capable of such combination with reinforcement, but the main types used commercially at present are polyamide (PA) and polypropylene (PP).

5.6 Long-fibre Reinforcement

In the production of a moulding compound (especially on a thermoplastic matrix), some amount of mechanical working is indispensable, with the result that any fibrous reinforcement is inevitably broken up into very short lengths. Anticipating this, very short lengths of fibre (typically 0.3 mm) have been used in thermoplastic moulding compounds. The mechanical properties of the compounds, however, are closely related to the length of the reinforcing fibre.

b2


For example, in an ideal PA 66 compound, reinforced with 50% glass fibre and with all fibres aligned along the length of the moulding, the flexural and tensile moduli increase rapidly as the fibre length is increased from 0.1 to 1.0 mm. As a result, technology has been developed to enable the use of long fibres (around 2 mm) in a thermoplastic resin matrix. These are produced, not by classical physical mixing, but by a process analogous to the 'pultrusion' process with thermosetting resin matrices, with internal lubrication additives to counteract the chopping effect of injection moulding. Similar effects have been measured with other fibres, such as aramid and carbon, and with other matrices, such as polypropylene and poly(phenylene sulphide). Long-fibre technology was pioneered by LNP Plastics when it was a subsidiary of ICI (and has since developed as a major independent compounder). Another compounder active in the field is the US group RTP. Ticona is another producer and a recent entry has been the French group Atochem (now AtoFina), which has developed a polypropylene material under the name Pryltex, in a joint venture between Appryl Composites and Multibase. Appryl's Pryltex range offers fibre lengths of 12, 18 and 25 mm and can accommodate glass contents of 10-50% by weight. The process is patented and involves coating the glass fibre roving with polypropylene and combining and cutting to the specified lengths after cooling. Compared with 20 and 30% glass-reinforced nylon, PP with 30% long glass fibre is claimed to be 10% fighter and faster and easier to mould. A long fibre-reinforced polypropylene material system, designed for automotive applications, is under development by the resin manufacturer DSM and the glass manufacturer Owens Corning, in a joint venture. Described as bridging the gap between injection moulded short fibre-reinforced plastics and press-moulded glass mat thermoplastics, the technology uses modified polymers and special mould design to allow longer lengths of glass fibre to be injection moulded, obtaining better mechanical performance. LNP Engineering Plastics published results of tests on a selection of die-cast metals compared with a 60% long glass fibre-reinforced polyamide 66 compound (Verton RF700-12EM). The conclusion was that (for moisture-conditioned samples) with a density lower than metals with the exception of certain magnesium alloys, a long fibre-reinforced PA 66 compound shows reasonable tensile strength, high impact, and good elongation. Flexural modulus, however, remains low. Table 5.8 Long fibre-reinforced tiiermoplastics: effect of fibre lengtfi Fibre length number average (mm)

Fibres longer than 0.2 mm (%)

Notched Izod impact strength (kjm-^)

0.2 7 0.32 1.38 3.54

35 57 89 99

17.0 29.5 32.5 39.0


53

Table 5.9 Properties of typical long-fibre thermoplastic compounds^

Fibre content Density Notched Izod impact Flexural modulus Tensile strength Heat distortion temperature

Unit

PA66/ glass

PA66/ glass

PA66/ glass

PA66/6 glass^

PA6/ glass

PA/ aramid

PP/ glass

% gm"^ kj m-^

35 1390 20.0

50 1570 27.0

60 1700 32.0

40 1420 22.0

50 1570 30.0

40 1240 8.3

40 1220 20.0

GPa

11.0

15.8

19.0

12.0

15.0

7.1

7.5

MPa

210

230

250

200

200

117

110

°C

256

261

261

218

218

246

156

^ Blends of PA 66 and 6 have similar properties, with a heat distortion temperature about 16-18°C lower. ^ Hot oil/grease grade.

Table 5.10 Long-fibre plastics compared with die-cast metals (23°C)

Ultimate tensile strength Yield strength. 0.2% offset (MPa) Elongation (%) Young's modulus (GPa) Charpy impact (un-notched) (J) Shear strength (MPa) Density (kg m-^)

Zamak 3

Zamak 5

Mg AZ91D

Mg AS41A

Mg AM60

Al A380

Verton RF70012EM

283 221 10 8 5.5 57 214 6600

331 228 7 8 5.5 65 262 6700

234 159 3 44.8 3 138 1827

210 140 4 45 4.1 n.d. 1770

220 130 6-8 45 6.1 n.d. 1800

324 165 3 71 4 186 2713

230 4 16 10 115 1700

Source: LNP Engineering Plastics

5.7 New Developments

The technology for compounding long-fibre materials is sophisticated, but a costefficient system (which might open the way for smaller companies to become involved) has been demonstrated by Krupp Werner and Pfleiderer, Germany. The process is claimed to offer pellets at a cost lower than pultruded forms and only slightly more expensive than conventional short glass-fibre reinforced pellets. It is more flexible than pultrusion and permits the combination of various matrix materials, and degassing of the compound. The key component in the equipment is a patented impregnating head, in which the glass rovings are wetted with polymer melt before they are fed into the compounding extruder, rather than being wetted inside the machine, as is normal. The fibres are then mixed, the melt is degassed, and the product is discharged. The key point is that, as the filaments are already wet when they

54


enter the machine, it has been possible to develop a screw configuration that gives gentle action and so causes little damage to the fibres. 5.7.7 Polyurethane/long

fibres

Long-fibre technology has also been extended to polyurethane reaction injection moulding (LFI-PUR) and has been used by Elastogran for mass production of large 1.3-7 kg mouldings for a heavy trucks, in LFI-PUR at the rate of 25 000 a year by KVG Kunststoff-Verarbeitungs, Geilenkirchen, Germany. Instead of using glass fibre in the form of a mat to reinforce the moulding, the LFI process uses glass-fibre rope, dispensed from a robot-controlled mixer casing, cut to length, and introduced into the open mould together with the liquid polyurethane. The technology is more flexible than using glass mat, particularly for threedimensional components, and allows the reinforcement density to be adjusted and apertures to be accommodated, in realistic series production. Waste is minimized and costs considerably reduced. Within a couple of months of startup, KVG was moulding 200 parts per shift and the target for full-scale throughput was reached in six months. Novel technology involving reinforcement of PVC with long glass fibre has been developed in the USA and will be commercialized by Decillion LLC, a 60:40 joint venture between glass fibre manufacturer Owens Corning and PVC manufacturer Geon. Technically, any combination of glass fibre and PVC is usually regarded as very difficult because of the high viscosity of the matrix polymer, but the new material, with up to 40% glass, is three times as stiff as unreinforced PVC, with a heat distortion point higher than 9 3°C. 5.7.2 ABS/long fibres

New technology for reinforcing ABS with long fibres has been developed by Dow Plastics. It is described as 'Vitamins' (because it can be introduced in the feed hopper of a plastics processing machine) and involves the use of a thermoplastic polyurethane as a compatibilizer between the glass and the ABS matrix (for it has good compatibility with both). The polyurethane/glass fibre can be added to the ABS matrix at loadings of from 20 up to 60%, producing a reinforced thermoplastic compound with physical and chemical properties similar to those of semi-crystalline engineering thermoplastics such as nylon, but at a more attractive price. The limitation, at present, is on the operating temperature, which is given as 98.8°C. Dow claims it has some commercial applications, citing office furniture, sports equipment, and luggage, but the technology could be particularly interesting in production of sheet (included co-extruded types) for thermoforming. 5.7.3 Shaped fibres

Short fibres with lumps at each end could prove a useful and practicable way of improving the strength of composites - simply by providing a mechanical key in


55

the matrix to prevent pull-out of the reinforcement, according to researchers at the Los Alamos National Laboratory (LANL). Working with shaped fibres made from commercially available polyethylene grades in a polyester matrix, they have found that the fibres are firmly anchored into the matrix at each end by virtue of the wedge shape, but are only weakly bonded along their length. This allows the fibre to help carry the loading, and it has proved possible to configure the shape and size of the bone-shaped ends so that they do not undergo the stresses that often snap fibres and so limit the performance of a short-fibre composite. Compared with composites made of the identical materials but with straightended fibres, the bone-shaped fibre composites shows higher toughness and strength. Significantly, they are also much more resistant to crack-propagation, as the mechanically anchored fibres actually bridge the crack and hold firm. Computer modelling is now being introduced to help better understand the experimental results and aid in predicting the results of using other materials or different designs of fibre.


Sales of advanced and inorganic fibres are expected to increase globally at 9.3% a year up to the year 2002, according to Business Communications Co. Inc. (BCC). In the USA, the growth rate will be 10.8% a year, to reach a total market value of over US$1 billion. Development of high-performance fibres and the markets for them have been strongly infiuenced by the demand from military applications (which promoted the development of both carbon fibre and S-glass fibre). But, as the 'Cold War' ended, much of the military budget for new weapons also faded away, while the ever-increasing spiral of costs has also forced the military to examine more cost-effective solutions. As a result, manufacturers of fibres are now trying to maximize the commercial potential of advanced organic and inorganic fibres. The world market was over US$1 billion in 1997, with the US market by far the largest segment, representing over 60%. This situation will continue for the next five years forecasts BCC. The use of high-performance carbon fibre is expected to grow as prices are reduced. As a result of improved production technology and increased capacity, prices of carbon fibre, which were in the region US$26.5-33 kg~\ have come down to the lower level, but are still prohibitive for applications in automobiles and railways. However, a level of US$11 kg~^ (representing a 50% reduction) has been put forward as a guideline for large users. Compared with glass fibre, carbon delivers comparable physical properties at around 2 5% the weight, but this is not enough to offset a cost increase of some 4.4 times. But, at a price of US$ 11 kg~^ (as projected by Zoltec) the cost penalty is only 1.8 times where the user is looking only for tensile strength and comes down to 1.3 times where the key property is tensile modulus.

56


As the cost of the precursor can account for as much as 70% of the total production cost of carbon fibre, an important contribution to cost reduction has been the development of other precursors. Table 5.11 Cost comparison between glass fibre and carbon fibre, specific mechanical properties (glass cost = 1.00) E-glass

Structural requirement

Compressive strength Tensile strength Tensile modulus

Carbon (2000)

Carbon (1997)

Weight

Cost

Weight

Cost

Weight

Cost

1000 1000 1000

1.00 1.00 1.00

419 267 147

6.91 4.40 3.14

419 267 147

2.88 1.84 1.30

Source: Reinforced Plastics

Table 5.12 Capacities for carbon fibre, worldwide, 1 9 9 6 - 2 0 0 0 (tonnes) Company

Location

Precursor

Capacity (1996)

Capacity (2000)

Toray Toho Rayon Amoco Hexcel Mitsubishi Zoltek Akzo Nobel SGL Totals

Japan Japan USA USA Japan USA/Hun gary USA/Holl;and UK/Germany

Special Special Special Special Special Textile Textile Textile

3700 2900 1900 1800 1800 1600 1 ()()() 900 1 5 700

7700 5100 1900 2100 3400 18 100 4800 2 700 45 900

Source: Reinforct.'d Plastics

CHAPTER 6 Modifying Specific Properties: Appearance - Colorants, Pigments, Dyes, Special Effects The use of pigments by people goes back to cave-dwelling times, but it is only in the last century or so that colour has become one of the foundation stones of the modern chemicals industry. The development of the plastics industry, however, brought colour to levels that could never have been attempted before. It has also raised fundamental questions about colour and how it is produced that have led to an explosion in development. The almost limitless possibilities of colour in plastics - particularly in transparent matrices like polystyrene - in turn gave birth to the compounding industry, as polymer manufacturers became unable to deliver the wide choice of colours demanded by markets such as cosmetics and packaging, and promoted a new industry of companies specializing in matching colours and compounding small batches, with great flexibility and rapid response. Most of those pioneers are still in existence (in some form), supplying formulations worldwide, with consistent batch-to-batch quality, saving processors time and inventory costs. As compounding developed, other additives were included in compounds, and colours themselves were developed offering other technical properties. Apart from soluble dyestuffs (which are used to a small extent in transparent and fluorescent products, for internal reflection and absorption) the colorants used in plastics are basically insoluble organic and inorganic pigments. From the beginning they have been mixed into plastics by the processors (often using the most basic equipment) but it is vital that they are properly dispersed in the matrix - and this is probably the most powerful argument in favour of separate compounding. Generally, inorganic pigments have good temperature and light stability, while organics meet the most demanding colour requirements. Toxicity and environmental considerations. Governing the use of pigments in plastics in contact with foodstuffs (such as packaging, food handling and processing equipment, kitchen appliances, working surfaces), most countries have their own legislation based either on actual permitted content of a specific ingredient, or maximum permitted extraction. There is concern in some countries about the effects of heavy metals entering the environment (as via dumped plastics waste). This has produced a trend away

58


from pigments based, notably, on cadmium and the search is on to replace these with others of equal effectiveness. Table 6.1 At a glance: pigments, dyes, special effects Function

Colorants act either by absorbing parts of the spectrum and reflecting other parts (solid pigments, dyes), or by transmitting only certain wavelengths (transparent colours); these effects can be combined with multi-layer structures, also using interference patterns to achieve an effect

Properties affected

Colour, appearance: some pigments can also give shielding against UV light


Organic; inorganic; pearlescent; metallic; special effects

Disadvantages

Can contaminate other materials/equipment unless kept separate or used in dust-free/non-polluting form; migration if not correctly compounded; thermal stability in processing at high temperatures: replacement of heavy metals with pigments of comparable performance

New developments

Easier forms for use/incorporation in compounds; colour concentrates, liquid colours; improved dispersibilty, better thermal stability; replacement of heavy metals; introduction of new chemistry

6.1 Main Types of Pigment and Colorant

Pigments are usually supplied as dry powders of various specific gravity and bulking value. Care is needed in handling, not simply because of the cost of the pigment, but also because it may present a dust hazard. Safe, dust-free formulations are now the general rule, but with so many other priorities many processors have clearly decided that colour is not their problem, and prefer to buy material ready-coloured. 6.7.7 Mixed metal oxides

These pigments are synthetic minerals. The desired colour is achieved by selecting specific metal oxides, based on metals such as chromium, nickel, antimony, titanium, manganese, cobalt, aluminium, zinc, iron, and copper. They are characterized by good heat stability, insolubility, excellent chemical resistance, non-bleeding/non-migrating, excellent weathering and lightfastness, good dispersability, good hiding power, strong, bright colours, and nonwarping. 6.7.2 Dyes

These are transparent and give bright colours in light. Most have relatively poor light fastness and limited heat stability, but will tend to retain their colour better

Modifying Specific Properties: Appearance - Colorants, Pigments, Dyes, Special Ejfects

59

than pigment systems because, as with all colorants, it is the surface layer that is affected by exterior conditions such as light and, while dyes will similarly suffer fading on the surface, their transparency gives a real depth of colour unaffected by surface influences. Dyes can also be subject to migration of colour, which is the subject of legislation for critical products, such as food-contact applications and toys. The choice between pigment or dyestuff depends on the compatibility of the resin matrix and the need for solubility. Other factors influencing selection include stability of colour during use, especially on exposure to light, air, and moisture, but also during processing. Some thermoplastics, such as the engineering types, require higher temperatures for moulding or extrusion, which may discolour a pigment system that is perfectly satisfactory with other materials at lower processing temperatures. Other important factors are strength/depth of colour, electrical properties, and resistance to migration. 6.7.3 Liquid

colours

A third form in which colorants are supplied is in liquid form, using a very precise metering unit mounted on the processing machine. As a direct method of colouring on the machine, this technology has been held back by technical

Figure 6.1. Structures of inorganic pigments: (top) rutile-cassiterite structure of inorganic colour pigments and (bottom) the spinel structure. (Illustration: Ferro Corporation)

60


difficulties, particularly at the dosing stage, but its popularity is growing and it is becoming clear that it is complementary to masterbatch, rather than in competition with it. It is widely considered best suited to long runs, where dosing can be more controlled, but the latest equipment (such as Colortronic's new lowrate gravimetric additive feeder, Graviblend S) is claimed to bring colour changes down to seconds. Recent development has concentrated on liquid colours for PET, to meet the huge demand from the packaging sector. Ferro's SpectraFlo Type 99 is opaque, complementing its range of transparent colours, meeting FDA rules and offering a rapid colour change at a let-down ratio of 1000:1. A clear-tint PET green from Milliken is said to have advantages over other liquid pigment dispersions for PET, with cost savings over pre-coloured PET.

6.2 Addition of Colorants

Originally, pigments were dispersed in plastics simply by dry blending in a tumble-mixer - or in an oil drum. The plasticizing function of an extruder or injection moulding machine also offered a reasonably good method of dispersing a pigment but the penetration of plastics into more critical markets brought demands for greater homogeneity and consistency. To achieve best results, however, pigmented compounds need to be prepared before moulding, using dedicated equipment such as a compounding extruder, or pigments must be formulated as concentrates, in a form giving trouble-free mixing with virgin material alongside the moulding machine. Concentrates or masterbatches are consistent, simple, and safe. They usually come in a granular form, in which the concentrated pigment is dispersed in a polymer carrier (such as polyethylene) that is compatible with the matrix resin. The let-down ratio is usually 0.5-2%, depending on colour, host material, and part thickness. The advantages claimed include cost savings due to less handling, quick colour changes, savings with lower inventory and reduced storage requirements, no pollution from colour particles in the air, and easy and clean to use. Colour dispersion is so good that precise measuring and mixing are not essential (but good screw back-pressure is recommended), while there is no adverse effect on the physical properties of the host material. A typical range will cover around 400 colours, with a minimum order quantity of 25 kg, but some suppliers can supply down to 1 kg at a surcharge. Colour matching can also be done, usually on a minimum quantity of 50 kg. There are around 200 producers of colour masterbatch, the leaders being Cabot, Schulmann, Ampacet, andFerro. Whether the colour is added by a specialist compounder or by a good technical processor, the quality depends on dispersion and match. The pigment is dispersed by 'wetting' the particles with the resin, and the size and shape of the particles are therefore of great importance, as also are the rheological properties of the resin matrix. Apart from colour fidelity, good dispersion also plays a role in

Modifying Specific Properties: Appearance - Colorants, Pigments, Dyes, Special Ejfects

61

maintaining the physical properties of the compound, while inadequately mixed pigment may even damage the processing equipment. Dispersion of a critical pigment in a ^difficult' resin matrix may be promoted by special dispersant additives. Pigments are generally robust, but over-mixing can be as serious a problem as under-mixing. Stability of the pigment is an important factor. Many pigments can deteriorate when exposed to excessive heat and, where the matrix is an engineering thermoplastic, a pigment with higher thermal stability is needed, to resist the higher processing temperature. Generally, large-particle pigments, such as titanium dioxides, are easier to handle - but carbon blacks, by their very nature, demand specialist handling (and are usually compounded in dedicated sealed units). Organic pigments also have fairly large particles, but they tend to be light and 'fluffy', and may also carry electrostatic charges, all of which makes them difficult to disperse. Smallerparticle pigments provide a denser colour in the plastics matrix but their specific gravity can provide problems in metering/weighing. The sequence of blending, as well as the use of dispersing aids, is critical.

6.3 Replacement of Cadmium

Probably the main challenge to pigment development during the past 10 years has been the ecological drive to replace heavy metals which, it was feared, could leach out from landfills into the environment. Lead had already been phased out on the grounds of toxicity but, in Europe, there were national and supranational moves to ban the use of cadmium pigments also. The latest study (by the EU itself) concludes that cadmium pigments do not present any significant threat to human health or to the environment. A more far-reaching report on cadmium and cadmium oxide is expected. Technically it is not easy to produce an exact 'drop-in' replacement (especially at the same cost level). A key problem has been to produce a yellow that is as effective as cadmium. Economically there are also problems. Respondents to a survey by the Cadmium Association said that costs increased by 2-5 times: over 50% found that productivity fell by 10-25% when moving to non-cadmium pigments, particularly with polyolefins. Organic pigments are bringing their own strengths and weaknesses as they move into markets formerly held by cadmium and lead. In general they have excellent colour characteristics, but they can have lower stability, while increasing formulation costs. New pigments are being designed as blends of organic and inorganic compounds, using features of both to tailor to a specific application - but blends can retain weak properties from their individual constituents. The need to replace heavy metals has also stimulated the introduction of new chemistry. An important development has been that by Rhone-Poulenc of inorganic pigments based on sulphur, with a crystalline structure that can be doped with various metal elements (rare earths). The colour strength is reported

62


to be 3 0 - 3 5 % lower than that of cadmium but the opacity and dispersion characteristics are comparable. All are characterized by excellent heat stability (up to 2 50°C), as well as having high resistance to weathering and UV light. Ciba has developed a range of yellow pigments based on bismuth vanadate (BVA) some of which resist up to 30()°C. This type of pigment is known for its liveliness and freshness of tint, but heat stability is at present insufficient relative to the cadmium yellows. BVA yellow pigments are mainly used in semicrystalline polyolefins (such as HDPE) since they do not show any phenomenon of warping. Another possible alternative to cadmium yellows, lead chromates, and diarylid yellows is yellow chromophtal HRP - a brilliant all-round pigment with very good heat and light stability, which can be used in PVC, polyolefins, styrenics, and polypropylene fibres. Clariant has added more than 50 colours to its cadmium-free Universal range, making a total of 180 colours. Special effects have been extended to include wood, pearlescence, and edge-glow effects. Colloids has also added 15 stock film grade colour masterbatches to its existing 35 colours to meet the restriction on heavy metals in the EC Directive on Waste Packaging, 94/62/EC, Article 1 1 . Table 6.2 Replacements for cadmium pigment masterbatches Product

Pigment concentration

High-temperature suitability

Contains cadmium pigment

Heat stability (°C)

Light stability

(%) Yellow

5 5--60 40

Yes No

Yes No

300 260-2 70

7-8 6-7

Cream

60 55

Yes Yes

Yes No

300 3{)()

7-8 7-8

Beige

65 65

Yes No

Yes No

300 260

7-8 7-8

Orange

60 40- -45

Yes No

Yes No

270

7-8 7

Red

50- -55 35

Yes No

Yes No

300 2 70

7-8 7

Blue

5 5--60 40

Yes Yes

No No

280 280

7-8 7-8

Green

60 45

Yes No

Yes No

280 2 70

7-8 7

Grey

60 50- -65

Yes Yes

No No

300 300

7-8 7-8

3(){)

Source: Colloids

6.4 Pigments for Special Effects

New pigment technology (which is largely concerned with light-scattering techniques) offers a very wide range of special effects.

Modifying Specific Properties: Appearance - Colorants, Pigments, Dyes, Special Effects 6.4.7 Aluminium

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pigments

These offer effects such as bright metallic lustre, bright sparkle, pearlescent effects, and glitter. The pigments are entirely encapsulated by the polymer carrier, allowing easy and gentle dispersion. Dosage uses standard volumetric and gravimetric units, with little tendency to contaminate. A high metal content permits low dosage: 0.1-3% for moulded articles and up to 5% for film will provide good opacity. In engineering plastics a pigment content of 1-5% may produce a 5-15% reduction in strength, which may be offset by using a higher grade. Plastics coloured with aluminium can be recycled, and it is also possible to improve the appearance of recycled thermoplastics by the addition of aluminium pigments. Metallic pigments, especially for automobile applications such as bumpers, door panels, grips, buttons, hub covers, and scooter panels and wings, are a focal point of current development by Clariant Masterbatches Division. The company also claims it has the first colour masterbatch series for HDPE packaging with an anodized aluminium appearance, giving high reflectivity, chrome, and lustre. 6.4.2 Pearlescents

These are pigments based on thin platelets of transparent mica, coated with titanium dioxide or iron oxide, producing interference patterns. Titanium dioxide (Ti02)-coated mica pigments have a 2-10 )am particle size, for increased lustre, whiteness, and coverage; there are also silver sparkle effects. A two-tone effect can be obtained with absorption colours deposited directly on interference pigments of TiOi-coated mica (such as Mearlin Dynacolor). A 'frosty' effect can be obtained by combining pearlescent pigments with ultrafine titanium dioxide of 20 |im particle size, compared with the normal 200 |im, as a coating on the mica platelets The pigments (from Kemira Pigments) reflect different colours according to the angle of viewing. The coating strongly absorbs radiation in the UV part of the spectrum and shows most of its scattering power in the blue. TekPearLite colour concentrates give pearlescent effects: they include FDA-approved grades for cosmetics, toys, and food packaging. Colour and effect masterbatches have been developed by Hanna's subsidiary Victor International. They include a highly concentrated colour masterbatch (Hi-Strength) that can reduce inventory costs and is seen as particularly suitable for packaging where high opacity is required. There is also a new translucent pearl effect masterbatch range (Trans-Pearl) that includes thermochromic, marble, pearlescent, edge-glow, photochromic, laser marking, frosted, metallic, and speckled effects. 6.4.3 Light interference

pigments

These have recently been taken a stage further with the development of so-called 'flip-flop' pigments that present a different colour according to the angle from

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which the surface is viewed. This effect (which uses the same phenomenon as the wing of a butterfly or the shell of a beetle) is at present exploited mainly in special automobile topcoats, giving a car body that seems to change colour as it approaches and passes by. Considerable work on this technology has been carried out by BASF. A novel silicone polymer comprising a powder-like hquid crystal material is being developed by Wacker Chemie for the same effect. Helicone flakes make it possible to reproduce all shades within the spectrum, and also to produce shifts of colour as the viewing angle changes. So far, iridescent colours that shift with different angles and different substrates have been developed. Just four grades - copperred, gold, green, and blue - make it possible to reproduce all the shades within the spectrum. 6.4.4 Fluorescents

These have been developed in recent years, together with light-conducting pigment and dye systems, giving exciting possibilities, especially in display media. Luminescent solar concentration (LSC) units based on acrylic (PMMA) or polycarbonate (PC) sheets contain a fluorescent dye that collects daylight along the edge and can be used with photovoltaic cells, or to give increased visibility of printing in signs and signals. Some typical systems are BASF's Lumogen F range of fluorescent dyes, offering about eight years' resistance to UV light, and Hanna offers a full range of transparent fluorescent colours giving a light tint to flat transparent surfaces, scattering light and strong colour to the edges, and giving a surface-glow effect, used with GP styrenes, acrylics, and PC. 6.4.5 Thermae hromic and photochromic

pigments

These are micro-encapsulated liquid crystal systems, giving precise colour changes at specific temperatures, or when exposed to light. They are particularly interesting for packaging for food or pharmaceuticals, giving an indicator of storage or cooking state. Photochromic pigments change from colourless to highly coloured when exposed to UV light (such as sunlight) and revert when removed from radiation. They are organic, with excellent colouration in a wide range of polymers, and can be mixed to form a spectrum of colours or mixed with conventional dyes. Agricultural applications are particularly interesting, where use in 'polytunnels' can protect plants from over-exposure to ultraviolet and infra-red radiation. Other applications include sunglasses, security equipment, protective equipment such as welding helmets, and novelty products. Thermochromic pigments change colour with temperature, and there are compounds and masterbatches for injection, blow moulding, or extrusion. The pigments comply with FDA food contact regulations and can be used for novelty products and for products requiring warning indicators, such as baby bottles, thermometers, and kettles. Possible colour changes are: green to yellow, magenta to blue, and coloured to colourless. Typical ranges include Hanna/


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Victor's Chameleon organic pigment concentrate for polyolefins and styrenics, with colour changes activated in 10°C bands from - 2 5 to +58°C, and a range from Sibner Hegner, which changes from coloured to colourless at 5-15°C or 65-75°C. A breakthrough in photoluminescent concentrates is claimed by Ampacet, with the launch of four grades under the name Lumi. Based on a new concept that overcomes most of the limitations that have prevented widespread use of luminescent systems relying on radioactive elements, they demonstrate good hysteresis (enabling them to be charged and recharged many times without losing the ability to re-emit light) and retain their luminescence for several hours without exposure to a light source. They are highly heat stable (resisting temperatures above 300°C) and have good resistance to chemicals, but the most significant benefit is that they are non-toxic and non-radioactive, which opens the way to new application possibilities. A colour change that is triggered by light rather than heat has been introduced by Polycolour Plastics, with its new Dual Colour system. New longer-lasting phosphorescent pigment technology (activated with minimal light but then glowing for 2 0 - 3 0 minutes) has been introduced by Hanna Color (FX Nite Brite) which, with a proprietary laser marking system, will prove of great interest for applications such as emergency signalling and illuminated latches in automobiles. A series of innovative 'glow-in-the-dark' coloured compounds has also been introduced by RTF, offering designers a wider range of pastel colours (such as peach, pink, blue, cream, and green), for applications such as back fighting. 6.4.5.1 'Intelligent' heat proteetion for food products This is offered by a pigment system developed by Sachtleben Chemie, Germany. It can be incorporated in plastic films and food packaging, to control the temperature in heat-sensitive products. Visible light is kept away and heat may escape unhampered from the package. The product is said to be of interest for projects sponsored by the World Health Organization, aimed at prolonging the preservation of foodstuffs in developing countries, and for disaster relief operations. 6.4.5.2 High-performance dyes for CD manufacture These are offered by CMR Technology, Connecticut, USA, including CMR 1000 blended dye powder, a blend of dye powder and stabilizer (which requires only a single solvent, saving time and money). CMR claims to be the world's only independent source of dyes for CD-R and DVD-R and dye process technology. 6.4.5.3 Solar heat Epilin Heat Shield 900 is a dye that absorbs infra-red radiation while allowing transmission of visible fight, so blocking solar heat. It can be used in polycarbonate for automobile sunroofs and other glazing and can be added to polymer films for window and greenhouse film.

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6.5 Laser Marking

Demand for laser marking and, consequently, suitable colorants, is growing rapidly in packaging and technical products. Until comparatively recently it has been difficult to produce effective laser marking on plastics (such as for date/ batch-coding on packaged goods) but the development of suitable pigment systems has produced materials giving clearly contrasted marking on many types of plastics, no matter what the base colour. The effect is created by reaction both in the pigment and the polymer matrix and is irreversible. The pigments can be easily incorporated into existing formulations, with no major influence on the properties of the material, since they react at relatively low intensity in areas close to the surface of the moulded object. Transparent and naturally coloured plastics can be marked from light to dark without loss of transparency; light-coloured materials can be marked with sharp dark grey to black marking and contrasting colours from black to white can be applied to dark-coloured and black media. Pigments have been developed for both CO2 and Nd:YAG laser systems. Low pigment concentrations (from about 0.1%) provide dark marking and higher concentrations (up to 1.5%) show a light-coloured marking. Items can be marked at up to 6000 a minute (pulse CO2) and up to 2000 mm s~^ (Nd:YAG). A new pigment system that reacts to the laser beam itself, independent of the polymer matrix, is being developed by Merck, in addition to its present range of conventional laser marking pigments, based on mica coated with metal oxides such as selenium and ferric. A colourless energy-absorbing dye, compounded into a plastics material, or printed or painted on the surface, makes possible a novel laser welding technique, creating a joint that is almost invisible to the naked eye. Until now the normal practice has been to introduce an opaque absorber (usually carbon black) to act as the medium that heats in the laser beam to produce the weld. The new system, however, developed by the UK welding research association, TWI, Advanced Materials and Processes Department, permits two similar transparent plastics to be joined, with no visible weld line. The dye is Filtron, from Gentex, applied by painting or printing, compounding or inserted as a film.

6.6 Pigment Dispersants

Although desirable, organic pigments present problems because they are more resistant to breakdown and dispersion, with limited heat stability and less interaction with the matrix. No single dispersant has been able to correct this. Polyethylene and polypropylene waxes are used as carriers for pigments, but it has been difficult to ensure complete avoidance of agglomerates. AlliedSignal's Aclyn range of low molecular weight ionomer colour dispersants is claimed to offer improvements in division as well as wetting and


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distribution, aiding breakdown of any agglomerate in the pigment powder into smaller particles, preventing re-agglomeration by comprehensive wetting of the pigment surface. More intense colour can be obtained with the same pigment concentration that is heat stable to over 2()0°C and allowing high pigment loadings (as high as 70% for organic pigments). A new dispersion developed by Hiils (Vestowax P930 V) is claimed to produce increased colour strength in injection moulding and extrusion, allowing reduction in the pigment concentration used.

6.7 Multi-functional Systems

There is also a trend towards multi-functional pigment systems, such as CombiBatch concentrates from ReedSpectrum, which incorporate colour and functional additives. They can be used from PE to PET and include antiblocks, anti-static agents, flow modifiers, nucleating agents, and UV stabilizers. A new colour additive package from Morton (Injecta Color) includes lubricants and heat stabilizers, giving reduced cycle time without impairing colour and without warpage.

6.8 Pigments for Engineering Plastics

Increasing use of engineering plastics for Visible' applications, such as equipment housings, produce a demand for good colours that remain stable at higher processing temperatures. Yellow chromophtal GTAD (Ciba) is an anthraquinone-based material and is self-dispersing in resins and polyolefin fibres. Unlike classic pigments, it recrystallizes on return to ambient temperature and so offers a high thermal stability (up to 280°C). The pigment is also transparent and non-warping. A range of encapsulated heavy-metal-free single-pigment dispersions and custom colour matches that can be added at any point in the compounding process, developed by Holland Colors under the name Engineering Holcobatch, is claimed to improve the properties of filled (mainly glass-filled) plastics. Organic yellow, Bayplast Yellow G Y-5680 (Bayer), exhibits a unique spectral curve with heat stability and light fastness. It can be used with most thermoplastics, including polycarbonate and nylon (processing temperatures up to 320°C have been obtained). Cerdec's chrome titanate yellow is also recommended for engineering plastics, because of its above-average heat stability. A novel blue-shade red azo pigment, Engeltone 1115 (Engelhard), is an alternative to high-performance organics, complying with FDA limits for food contact and comparable in heat stability with many high-performance bright reds, such as DPPs (up to 300°C in ABS) - which it could replace, with up to 50% savings.

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6.9 The Effect of Pigments on Dimensions

A side-effect of replacing heavy-metal-containing inorganic pigments has been the need to accept organic alternatives that do not necessarily offer the same standard of performance. Pigments such as phthalocyanine blue and quinacridone red, for example, are less thermally stable and (although they cost less and offer excellent colouring ability and resistance to ageing) they have a reputation in the moulding industry as a cause of problems in shrinkage, warpage, and, occasionally, poor product performance. The UK National Physical Laboratory (NPL) has shown that phthalocyanine blue is an 'active' pigment, having a pronounced effect on the crystallization behaviour of semi-crystalline polyolefins, such as polyethylene and polypropylene. In effect, it acts as a nucleating agent, changing the temperature of crystallization and the nature of crystalline structures formed by the host polymer, as a result of heterogeneous nucleation. The shrinkage sensitivity of a compound appears to depend on the type of pigment used. Pigments affect dimensional stability: yellow 93 appears to cause most distortion but least shrinkage; a 15:3 modified blue pigment produces less out-ofplane distortion than other pigmented and unpigmented materials. Changes observed in crystallization behaviour, morphology, and anisotropic shrinkage in the pigmented compound are reflected in Young's modulus, yield stress, and failure strain (in the flow direction). Material ductility increases in HDPE, amplified in direct blending and impact performance using the falling weight method shows a statistically significant pigment/mix dependence. The research could be important for the packaging industry, where some problems have been encountered in tamper-proof bottle caps moulded in compounds using phthalocyanine blue. Table 6.3 Influence of pigment type on dimensional plates" Shrinkages

Shrinkages

Warpage W

Warpage W

Angle score

Yellow 62 Virgin Blue 15:3 (mod) Blue 15:3 Yellow 93

Virgin Yellow 62 Blue 15:3 (mod) Blue 15:3 Yellow 93

Yellow 62 Blue 15:3 Virgin Blue 15:3 (mod) Yellow 9 3

Yellow 62 Yellow 93 Blue 15:3 (mod) Blue 15:3 Virgin

Yellow 62 Blue 15:3 (mod) Blue 15:3 Yellow 93 Virgin

RW.

RWei

RWe2

RWe,

RWe4

Yellow 93 Blue 15:3 Yellow 62 Virgin Blue 15:3 (mod)

Yellow 62 Yellow 93 Blue 15:3 Virgin Blue 15:3 (mod)

Yellow 93 Blue 15:3 Yellow 62 Virgin Blue 15:3 (mod)

Yellow 93 Yellow 62 Blue 15:3 Virgin Blue 15:3 (mod)

Yellow 9 3 Blue 15:3 Yellow 62 Virgin Blue 15:3 (mod)

" Pigments are ranked in decreasing stability for both thick and thin order of importance, with those causing the most distortion at the top. Cells containing two or more pigments are equally ranked. Source: Polymers and Polymer Composites


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6.10 Colorants for Food and Medicals

Colorants are necessary materials in most forms of packaging, and they are critical to extraction and toxicity. This has been recognized from the beginning, and there are many pigments with satisfactory performance that are accepted for food-contact and medical applications.

6.11 Recent Developments

Technically, the development stress is now on high-performance pigments that also offer other properties, such as resistance to weathering, heat, light, and solvents, non-toxicity, and optical effects. The industry has been forced away from heavy-metal-containing inorganic pigments, leaving gaps that have only partly been filled by technical advances for mixed metal oxides. There have not been exact replacements matching the desired performance qualities in certain applications, such as anti-corrosive chromate-based primers. There is still a strong market in traditional materials, which will be replaced as technology introduces viable alternatives. 6.77.7 Colour

strength

BASF's range of azoic yellows (Paliotol) allows bright tints to be produced that are resistant to heat and light and suitable for food contact. Families of Paliotol yellows based on isoindoline and reds based on perylene can be used in polyolefins and also in the more technical plastics. From Engelhard is Meteor Plus 9384, which is claimed to have 70% greater colour strength than comparable reds (for use in PVCs, nylons, and engineering plastics). Also new is a barium-free yellow-shaded red, claimed to be less hygroscopic than barium products. New in the Microlen range are high-concentration pigment preparations based on polyolefins, giving good dispersion and suitability for automatic metering for masterbatch production, compounds, and colouring of elastomers. A new mixed-phase rutile yellow pigment (introduced by Bayer: Lightfast Yellow 62R) differs from conventional chrome rutile yellows in that it has higher tinting strength, better hiding power and gloss promotion, is suitable for lightfast, water-stable, and heat-stable pigmentation of plastics and coatings, satisfies purity requirements for food-contact applications. 6.77.2

Weathering

Cerdec Drakenfeld has introduced Yellow 10411, a yellow high tint strength chrome titanate, and 10411 greenish clean-shade for high-reduction PVC and polyolefins, and engineering plastics with above-average heat stability. Brown 10421, for rigid PVC, offers good weathering resistance and new black pigments also have high weathering resistance.

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BASF's Sicopal Yellow FK 42 3 7 FG is a heat-stable bismuth vanadate in a lowdusting form, designed for bright light weather-fast colours, especially in HDPE, ABS, and PA. Color-Chem International offers Amaplast Orange GXP, Red DJ, Violet PK, and Blue HB as new weather-resistant solvent dyes for engineering polymers, especially polyamides. They are claimed to offer better heat and light stability than existing solvent dyes and organic pigments, and good migration/ extraction resistance. 6.77.3 Natural effects

Customers are looking for products with a more 'natural' look, according to Hanna. Trend-setting applications now include white stone and earthenware (terracotta) effects, created for indoor and outdoor products, as well as 'wooden' chairs and tables. Building on its experience with fibres, beads, pearlescent, and fluorescent effects, the company has developed a range of natural effects. 6.77.4 New forms of pigment

Transforming the traditionally hard-to-use powder form of organic pigment into a unique microgranular form, Bayer's Coatings and Colorants Division has announced its new Bayplast Gran pigments, giving low dusting, high bulk density, and excellent dispersability in plastics and fibres. As well as contributing to a cleaner and safer environment, they also reduce waste, increase productivity, and provide more efficient shipping and storage. The process produces hollow microgranular spheres ranging from 150 to 175 |im, which contribute directly to high flow rate and low static cling. 6.77.5 Surface treatment

A surface treatment for organic pigments by Engelhard is said to contribute to lower volatile organic compound (VOC) levels, reduced costs, and improved performance. It also forms the basis for an improved naphthol red 170 organic pigment (Harshaw RX 3170). Holliday Pigments' Prestige R is pre-wetted to produce less dust, also increasing bulk density and boosting feed rates with volumetric feeders. Said to be the first time glass pigments have been offered coated with titanium dioxide, giving a brilliant star-like glitter, with depth and multiple colours, another range by Engelhard, under the name Firemist, offers exceptional chroma, colour purity, brightness, transparency, and reflectivity. 6.77.6 New pigment

chemistry

A family of organic pigments has been introduced by Ciba based on new colour chemistry, named diketo-pyrrolo-pyrrol (DPP). Chromophtal DPP products, ranging from yellow-shade to mid-shade red, are claimed to be the brightest, cleanest, and most opaque organic pigments available, offering bright, transparent


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colours with good durability and improved processing characteristics. They are heat stable to 2 70-285°C and can be used with polyolefins, PVC, polystyrene, and ABS, and can also be mixed with other pigments because they are inherently non-reactive. Isoxindigo is a new type of chemistry developed by Ciba Specialty Chemicals mainly for the engineering plastics market. Pure and brilliant shades of polymersoluble colorants, offering users new solutions, can be highly transparent, providing a broad scope of possibilities with very good fastness. They are also claimed to be very economical in use, giving good value both to processors and end-users for colouration of styrenics and engineering plastics. Unique resin technology is claimed to lie behind the introduction, by Elementis under its Tint-Ayd brand name, of a new range of colorants for all types of powder coatings, and new high-performance pigments for low- and zero-VOC waterborne coatings. It was developed covering a variety of types, including white epoxy/polyester, white polyester/triglycidyl isocyanurate (TGIC), and clear urethane/polyester. Differing from conventional phosphorescent pigments based on zinc sulphide or radioisotopes is a range based on strontium oxide aluminate chemistry, by Nemoto, Japan (LumiNova). Originally developed for watch and clock dials, they have many other applications, in appliances, sign boards, and emergency equipment, giving an afterglow period up to 10 times that of ZnS-based systems, activation by a wide wavelength band, up to 10 times greater initial afterglow brightness, and excellent weather and light fastness. For use in plastics, the preferred system is masterbatch or compound, as the pigment is a very hard substance with needle-like particles that are difficult to incorporate directly into a resin. For masterbatch, the processing temperature should be about 10°C higher than normal and the recommended machine configuration is one with a distributive screw design and twin hoppers, using the first to feed in resin and additives and the second to dose the pigment into the melt.

6.12 Market Trends

European consumption of pigments and colorants is estimated (by Rapra Technology) at about 728 000 tonnes in 1997, rising to nearly 900 000 tonnes in 2002. An estimate by BCC values the market at nearly US$ 1.4 billion. Production of colour compound is estimated at 1.5 million tonnes in Europe, mainly for cable and pipe grades and engineering resins. Demand is likely to slow down, in preference to coloured masterbatch. Pigmented masterbatches are used to modify an estimated 53% of polymers processed (and 45% of all performance additives used in Europe are incorporated via masterbatch). Compounder Ampacet estimates that worldwide consumption of masterbatch will reach 2.15 million tonnes in 2 0 0 1 . Film, blow moulding, and injection moulding make up about 70% of consumption. There are around 200 producers of colour masterbatch, the leaders being Cabot, Schulmann, Ampacet, and Ferro.

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Intertech estimates the world market for high-performance pigments at over 550 000 tonnes a year, and showing an annual growth rate of 5-7%. The main segments of the market are inks and paints (55%) and plastics (35%), with other applications sharing the remaining 10%.

CHAPTER 7 Modifying Specific Properties: Appearance - Black and White Pigmentation

Table 7.1 At a glance: white pigments Function

White pigmentation, high reflectance; modification of other colours, increased brightness

Properties affected

Appearance and surface; may also give higher UV protection to the plastic, improved weather resistance: some mineral whites will also improve mechanical properties


Titanium dioxide; zinc sulphide; blanc fixe; white calcites

Disadvantages

Possible problems of handling in powder form, needing extra ventilation: titanium dioxide can act as photocatalyst, unless suitably treated

New developments

Improvement of presentation and dispersability: high-performance masterbatches with other additives

7.1 Types of White Pigment

7.7.7 Titanium

dioxide

Titanium dioxide (Ti02) is the most important white pigment used in the plastics industry. It has a higher refractive index than any other white pigment and has good chemical stability. It is also non-hazardous and possesses very good dispersability and good thermal stability. There are two commercially useful forms: rutile and anatase. Rutile has higher opacity and is considerably less photocatalytically active than anatase. It also has a slightly higher refractive index (2.70 as against 2.55), giving better light-scattering power. Rutile-type Ti02 also accepts surface treatments more readily, bonding better than anatase.

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Anatase is used mainly in paper and elastomers: in thermosetting resins systems, it retards gel time and may prevent cure altogether. The pigment is extracted from crude ore, removing impurities such as iron oxide. There are two manufacturing processes: Sulphate (46% of production, and declining): a multi-stage wet chemical process, batch or continuous. Titanium dioxide is dissolved in the raw materials by concentrated sulphuric acid, precipitating the hydrous salt. This is then calcined to produce one of the two crystalline forms, anatase orrutile. Chloride (54% of production, and rising): a two-stage process, at high temperature. Titanium ore is reacted with coke and chlorine to produce titanium tetrachloride. Purified titanium tetrachloride is then reacted with oxygen to produce rutile titanium dioxide. The chloride produced is recycled to the first stage. The process cannot produce commercial quantities of anatase. It is a more modern process and is considered preferable on environmental grounds.

7.1.1.1 Surface treatments Titanium dioxide absorbs much of the IJV radiation which would otherwise degrade a polymer matrix and so it also protects the polymer photochemically. Untreated, however, the pigment itself is photocatalytic. Although it converts most of the UV energy to heat, the remaining energy creates active or radical sites on the surface of the pigment particle. The reaction at these sites accelerates the breakdown of the surrounding polymer, leading to the well-known weathering effects of 'chalking' and loss of gloss. Virtually all titanium dioxide used in plastics pigmentation is surface treated. For use in PVC, the main purpose is to minimize photocatalytic activity but other effects should also be considered. On the negative side, high levels of surface treatment reduce the proportion of titanium dioxide in the pigment, thus significantly reducing opacity and tinting strength. However, by modifying the interfacial interactions between polymer and pigment, the treatment may also aid dispersion and reduce the requirements of power and shear when mixing. Especially for PVC, most Ti02 pigments also employ an organic coating, aiding the development of an optimal state of pigment dispersion and so ensuring that the maximum opacity and durability potential of the pigment is realized. The combination of inorganic and organic treatments determines whether the pigment is best suited to giving resistance to weathering and discolouration (for example, in UPVC window profiles) or to giving viscosity control and opacity (for example, in plastisols). The technology of treating titanium dioxide pigments is thus very complex. Property differences arise from the type, thickness, combination and method of application of surface treatment, as shown in the following:


75

Table 7.2 Melt flow index of polycarbonate, pigmented with 5% Ti02 showing the eff"ect of various surface treatments Virgin resin RutileTi02, with Rutile Ti02, with Rutile Ti02, with Rutile Ti02, with RutileTi02, with

modified siloxane 0.5% alumina, 0.5% polyol 1 % alumina, 0.5% polyol 1% alumina, 0.5% siloxane 3.25*)^) alumina, 1.5% silica, 0.5% siloxane

11.4 13.2 21.5 2 5.3 2 3.7 2 5.2

Source: Kronos

The level of photocatalytic activity may be reduced by surface treatment of the base pigment with suitable inorganic compounds. For pigmentation of plastics, including PVC, these are usually alumina or a combination of alumina, silica, siloxane, and polyol, or sometimes zirconia. The treatments function mainly by placing a physical barrier between the pigment surface and the polymer matrix, blocking the active sites and minimizing degradation. The effectiveness of a particular surface treatment depends on several factors, including the type of chemical compounds used, the amount applied, uniformity of treatment, and density of coating on the pigment particle. The original surface treatment, which is still the most popular, is alumina. Among other inorganics, silica is used less frequently and zirconium rarely. Inorganics are usually added to improve properties of the end product, but they also enhance slightly the dispersion characteristics. In addition, by forming a barrier between the titanium dioxide and the matrix resin, they inhibit undesirable chemical reactions. Organic surface treatments are, most often, polyols. Amines, siloxanes, and phosphated fatty acids are also used. Organics generally act as aids to processing and dispersion, promoting de-agglomeration, wetting, and dispersion of the pigment. All the major effects of organic treatments are concentrated on the surface of the particle and the figure for percentage composition usually indicates the amount on the surface. Alumina (aluminium oxide). This is used at levels from 0.5 to 3.5%, applied during manufacturing. It is compatible with all main resin systems, but can give problems by outgassing of its water of crystallization at elevated temperatures, the water vapour remaining as a 'pocket' in the melt and finished product. In thin films this causes voids (known as 'lacing'). When processing at above 250-300°C it is recommended to use particles with 0.5% alumina or below. Silica (silicon dioxide). This is used with alumina to improve the weathering resistance of certain grades of titanium dioxide (as for PVC rigid compounds for outdoor applications). The alumina and silica together form a surface impermeable to UV light, preventing pigment/matrix reactions that are triggered by exposure to UV light.

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Polyols and amines. These enhance wetting and dispersion in almost all polymer systems, giving broadly the same results (but polyol treatments are possibly better with vinyl compounds). Siloxanes. These give about the same performance as polyols and special grades are effective in retarding undesirable reactions in polycarbonates. In excessive proportions, however (above about 1%), siloxanes can separate from the Ti02 and migrate to the surface, affecting printability and sealing characteristics. 7.7.7.2 Titanium dioxide grades A typical range of grades includes: • • • • • •

Stabilized, surface-treated micronized rutile, chloride process. This gives the highest weather stability in resin systems, especially PVC and polyolefins; good dispersability, brightness, and tinting strength. Stabilized, surface-treated micronized rutile. This has good weather stability and very good dispersability, especially in PVC. Stabilized, surface-treated micronized rutile. This has very good photochemical stability and dispersability in aqueous systems; good for urea and melamine moulding compounds and rigid PVC. Surface-treated micronized rutile. This gives brilliant shades in colour compounds, high tinting strength, and good dispersability; good economic value; weather stability limited in PVC with lead stabilizers. Surface-treated micronized anatase. This has high tinting strength, bluish colour tone, outstanding brightness, and dispersability. It is less abrasive than rutile pigments, but not recommended for outdoor applications. Untreated micronized anatase. This has very good brightness, bluish colour tone, high tinting strength, and good dispersability in aqueous systems.

7.1.1.3 Opacity and tinting strength Key criteria for all pigments (and particularly whites) are opacity and tinting strength. Opacity is particularly important in thin-section applications, where a highly opaque pigment can serve well, even at a lower concentration. In thicker sections it may be less important - but it is as well to remember the other side of the coin: lower concentrations of Ti02 pigment may detract from durability. Tinting strength measures how well a given amount of pigment affects the overall colouring of the moulded product. With Ti02 this means how well it lightens a coloured compound, or adds whiteness and brightness to a white system. This is important not only in white compounds but also in compounds where the colouring influence of other additives must be masked. With titanium dioxide, the development of opacity and tinting strength depends on light-scattering power, which is governed by refractive index, particle size distribution, Ti02 content, and dispersion in the polymer.


77

The greater the difference between the refractive index of the pigment and its surrounding medium, the higher the light-scattering power, and therefore the opacity and tinting strength. Control of particle size distribution is critical if the maximum opacity potential of Ti02 is to be realized. For the most efficient light scattering, the particle diameter should be about 50% of the wavelength of the Ught to be scattered. So, some grades of Ti02 pigments are produced to maximize the number of particles in the range 0.20-0.40 jam, which is approximately half the 4 0 0 - 7 0 0 nm range of the visible light spectrum. The effect on properties of particle size distribution of titanium dioxide is: • •

0.2-0.4 |im: particles develop opacity 0.4-1.0 jim: particles affect durability

The actual Ti02 content of a pigment is an important factor in the opacity developed by a specific pigment. Typical grades have a content of 8 8-9 7%. Good dispersion is also a key criterion in developing high opacity and tinting strength. Maximum values will be developed only if the number of aggregates and agglomerates is few (and those that are present are well distributed throughout the polymer matrix). Undertone is the term used to describe the influence of a Ti02 pigment on the colour of a tinted system, resulting from the small differences in the proportion of light scattered at different wavelengths in the visible spectrum. Differences in undertone are less apparent in white compounds than in tinted compounds. Undertone is usually expressed as the difference between the red and blue reflectance, normalized against the green reflectance, as measured in a grey tint: Undertone = — where Rr = red reflectance, R\j = blue reflectance, and Kg = green reflectance. The more negative is this value, the bluer will be the undertone of the pigment. The undertone may also be expressed as a CIE b-value measurement in a standard grey flexible compound, and compared with the b-value of a standard Ti02 in the same system. Undertone is a function of pigment particle size. Ti02 pigments with an average particle size of close to 0.20 )Lim impart a bluer undertone to thick sections than do pigments of a larger particle size. Larger particle sizes give a more neutral or yellow undertone. But for thin, translucent items the appearance of colour arises from the transmitted light, and the effect of particle size is reversed: for bluer transmitted light, larger particle sizes, neutral or yellow undertone products, are selected. When colour matching tinted compounds, it is usually necessary to use a titanium dioxide with the correct undertone - although compensation for small differences can sometimes be made by adjusting the tinting system.

78


7J. 1.4 Colour Pure titanium dioxide scatters all wavelengths of visible light uniformly, and therefore appears as brilliant white in a colourless plastic. Pigment colour is essentially dependent on purity, so maximizing the potential for producing a brilliant white. 7.7.2 Zinc

sulphide

Zinc sulphide (ZnS) offers a good alternative to Ti02 pigments, where these cause technical problems. Pigments have various concentrations of barium sulphate, characterized by high brightness and very good light stability. ZnS pigments absorb less UV radiation than Ti02 pigments. They therefore have a wider UV 'window', giving the highest efficiency of optical brightener: fluorescent additives also retain their effectiveness, giving a brilliant appearance, and photoinitiators in UV-curable paints remain effective when pigmented with zinc sulphide. Tinting strength depends on ZnS content. Micronized grades are easily and homogeneously dispersed in plastic compounds. Particle size is 0.3 )Lim (regarded as optimum for a sophisticated white pigment). Because of low Mohs hardness, ZnS pigments cause virtually no wear on moulds and do not impair the mechanical strength of fibre-reinforced plastics (in contrast to abrasive pigments such as Ti02). Their main applications are in thermosetting compounds, glass fibre-reinforced thermosets and thermoplastics, and polyolefins. Table 7.3 Comparison of the hardness of pigments Mineral

Mohs hardness rating

Diamond

10

Corundum

9

Topaz

8

Quartz

7

-silicate

6

-phosphate

5

Fluorspar

4

Limestone

3

Rock salt

2

Talc

1

Pigment

Titanium dioxide (rutile) Titanium dioxide (anatase)

Barium sulphate, zinc sulphide

Source: Sachtlehen

Compared with rutile titanium dioxide, zinc sulphide offers white pigments for plastics that are non-abrasive, catalytically inactive, dry lubricants. They can reduce friction, polymer decomposition, and the wear of processing equipment.


79

Uncoated and surface-treated (HDS) grades are available, to improve dispersion. The micronized grades in particular are easy to disperse and are suitable for dissolver grinding. Low oil absorption (13 compared with about 20 for titanium dioxide) allows higher loadings while maintaining good rheological behaviour and improved flow properties of pigment pastes. Good dielectric properties make the pigments particularly suitable for electrical and insulation applications. Table 7.4 Zinc sulphide compared with titanium dioxide for glass-reinforced thermoplastics Compound

Concentration

(%)

Retention of original values (%) Tensile strength

Izod impact

Gardner impact

TiO,

ZnS

TiO,

ZnS

Ti02

ZnS

Polyamide 66, 30% glass

0.05 0.50 1.00 2.00

89 84 83 81

86 86 82 87

72 60 60 60

100 100 100 100

68 69 59 56

100 100 100 100

Polycarbonate, 10% glass

0.05 0.50 1.00 2.00

83 83 83 81

96 95 92 91

73 73 73 63

90 90 77 73

100 100 100 100

100 100 100 100

Polypropylene, 30% glass

0.05 0.50 1.00 2.00

94 89 86 85

100 100 100 100

92 83 83 67

68 68 68 65

96 100 100 lOO

100 100 100 100

Polystyrene. 20% glass

0.05 0.50 1.00 2.00

98 98 99 100

85 87 93 100

84 100 100 100

69 73 76 78

85 100 100 100

85 87 90 93

SAN. 20% glass

0.05 0.50 1.00 2.00

95 92 91 89

100 100 100 100

60 56 55 50

82 87 75 70

100 100 100 100

92 95 100 100

ZnS pigments are characterized by low binder requirement, good rheological properties, resistance to flocculation, and suppression of floating. They also have good anti-corrosion properties, and can be compared with zinc phosphate pigments. In some cases, ageing resistance can be improved. Weather stability is very good in polyamides and melamine compounds, but limited in most other plastics. Partial substitution of Ti02 pigments with double the quantity of ZnS does not impair brightness, pigment dispersion, or melt flow index of a masterbatch, but reduces friction and abrasion and increases temperature stability. It can thus act as a processing aid, especially in linear LDPE. The pigments are, for all practicable purposes, free of heavy metals: they are hsted in the US FDA Code of Federal Register (Part 178) and meet the pigments Recommendation IX of the German Federal Health Ministry (EGA), but not the French Circulaire No. 176 (dated 2 December 1959), which sets a maximum limit of 0.2% for acid-soluble zinc.

80


7.13 Other white pigments and extenders

A number of other fine-particle minerals offer very good whiteness properties and dispersability and can often be used as extenders to titanium dioxide, reducing the overall cost. 7.1.3.1 Aluminium silicates Fine-particle aluminium silicates (kaolin) have a high specific surface and low grit content and are easily dispersible in plastics, increasing the hardness and elasticity. Mechanical properties are generally lower than with the more coarse fillers. Thermo-optic treated grades have high whiteness and can be used to extend titanium dioxide and other more costly pigments. Calcined kaolins have good electrical properties, low compression set, and low water absorption, for use in cable formulations. 7.1.3.2 Barium sulphate (/blanc fixe') Precipitated barium sulphate ('blanc fixe') is an inert white filler, resistant to acid and alkalis, and has very good weathering resistance. It does not absorb light from the ultraviolet to the infra-red range and so does not impair the briUiance of colour pigments. Particle sizes range from 0.7 to 3.0 |im. DispersabiUty and lack of grit are high: hardness and stiffness of plastics are improved without effect on surface quality (especially gloss and colour brilliance). It is also used to increase density and X-ray opacity, especially for toys and medical articles, and improves sound insulation values. Special grades increase light scattering without absorption in semi-opaque compounds such as lampshades, PC and PMMA sheets, and PVC film. Ultrafine particle grades (less than 0.2 jim) have been developed as nucleating agents for partially crystallized thermoplastics. Natural barium sulphates (barytes) are inert and allow very high loadings: fine-particle grades are preferred to increase the density of a plastics compound, while coarse particles are better for acoustic applications, especially in automobiles. Blanc fixe micro is a white inorganic powder for plastics and coatings, comprising barium and sulphate. It is practically insoluble in water, organic solvents, and acids/alkalis. It is produced from barytes, with removal of impurities, achieving a narrowly defined particle size distribution. Titanium dioxide production technology is used for finishing. Its particles are almost as fine as those of titanium dioxide pigments (barytes, 4 |am; synthetic barium sulphate, 3 |im; blanc fixe micro,0.7 |im; titanium dioxide,0.3 \xxn). In use it is notable for low binder replacement, ready dispersability, extreme fineness, low agglomerate content, and (in coatings) high gloss. It can also act as a 'spacer' between white or coloured pigments, potentially reducing titanium dioxide by 5-15%, or reducing pigment costs, or raising solids content. Cost can be reduced by about 5% without detriment to properties. 7.1.3.3 Calcium silicate A needle-like, non-toxic calcium silicate (wollastonite) is used to reinforce thermoplastic and thermosetting resins. Various grades, with and without


81

organic surface coating, are available. Wollastonite also has interesting properties as a reinforcing filler and is expected to become more widely used in future. 7.1.3.4 Magnesium silicate Very pure, white platelet magnesium silicate (talc) is used to reinforce and nucleate partially crystalline thermoplastics, especially polypropylene and polyamide. It is used more as a reinforcement, giving good stiffness and dimensional stability. Table 7.5 Properties of white pigments and fillers Surface modified

Relative tint reduction^ (approx.)

pH value (approx.)

Density

Weather resistance

Light fastness

Titanium dioxides Rutile chloride

Al203Si02org.

102

8

4.0

Very good

Rutile

Al2O3SiO.org.

90

8

4.0

Good

Rutile

AI2O 38102

90

7

4.0

Good

Rutile Anatase Anatase

AbOiOrg. Al203org.

102 87 85

8 8 8

4.1 3.9 3.9

Moderate Fair Fair

Very good Very good Very good Good Moderate Fair

Type

VAnc sulphates Micronized ZnS normal 60% 30% Micronized 30%

org. D:org. D: org. org.

62 55 37 24

7 6-7 7 8

4.0 4.0 4.2 4.3

Fair^ Fair^ Fair^^ Fair^

Good^ Good^ Good^ Good^

D: org.

22

7

4.3

Fair^

Good^'

9

4.4

Very good

9

4.4

Very good

Very good Very good

Barium sulphates 1.0-3.0 |Am

—

Micronized

org.

Other materials Barytes

-

-

7-10

4.0-4.3

Very good

Kaolin

-

-

5

2.6

Very good

Talc

-

-

9

2.8

Very good

Wollastonite

-

-

10

2.9

Good

"

Very good Very good Very good Good

^ In PVC according to DIN 53 775, with 0.025% carbon black and 3% pigment (ref pigment standard Ti02 = 100). ^ Depends on system: very good in polyamides and melamine/formaldehyde moulding compounds. Source: Sachtleben

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7.1.4 White

masterbatch

White masterbatch is produced typically with 50-75% additives, for let-down at 3-4% (film), 1-2% (universal grades), and 3% (blow and injection moulding). Table 7.6 Typical grades of white masterbatch Base polymer

Colour index pigment

Recommended applications

(%) 50

White 6

50

White 6, blue 29

High pigment concentration, for extrusion and injection moulding High pigment concentration, for sheet extrusion, moulding

70

White 6, white 18

75 60 60

White 6. white 15 White 6, 18, blue 29 White 6

75

White 6, white 18

70

White 6, white 18

70

White 6. white 18

50

White 6

Economic masterbatch for injection moulding and film requiring anti-blocking Blow moulding, injection moulding, film Blued white for blow moulding, extrusion High-quality thin-gauge film, especially suitable for HDPE film Medium-gauge film, where good anti-blocking is needed Economic masterbatch for film, moulding, extrusion Low-cost masterbatch for film extrusion, moulding High-quality thin-gauge film

Polypropylene

50 60

White 6 White 6. white 18

Injection moulding polypropylene Sheet and pipe extrusion polypropylene

Universal

75

White 6, white I 8

75

White 6

60 60

White 6, blue 29 White 6 plus optical brightener

Injection moulding; disperses well in polyolefins, styrenics and engineering polymers Injection moulding; disperses well in polyolefins, styrenics, and engineering polymers Injection moulding, multi-purpose High pigment concentration, for sheet extrusion, moulding

60

White 6

Additive

Polystyrene

Polyethylene

Polyamide

High pigment concentration, for polyamide extrusion and injection moulding

Source: Colloids

7.1.5 New

developments

A novel process for producing ultrafine particles of titanium dioxide, which are optically transparent but retain their opacity to ultraviolet radiation, has been developed by DuPont. Based on work of its speciality chemicals group, it is a


83

hydrothermal process using amino titanium oxalate as the precursor, which differs from other such processes by producing exclusively rutile particles, instead of a mixture of Ti02 phases, such as rutile and anatase. It does not require additional calcination stages, which are expensive and may also produce agglomerates, impairing the transparency of the Ti02 particles. Particles made by the process have a uniform size distribution of less than 100 nm. They could be used in plastics food packaging, coatings, and automotive clearcoats, and in many other sectors vulnerable to UV light. The company has also introduced Ti02 pigments with outstanding optical and rheological performance at masterbatch loadings up to 80% pigment/20% resin (Ti-Pure), to meet a worldwide trend towards highly loaded masterbatches. A new generation of Ti02 concentrates, giving brighter colours with exceptional hiding power (50, 70, 80%), has been introduced by Ampacet, aimed at cast film and extrusion coating, heat stable at 343°C. TST/200 is a new series of highly loaded white concentrates for high-temperature/high-speed extrusion coating and cast film. It has good pigment dispersion, reduced die build-up, lower moisture pickup, bluest undertone, and is compatible with a wide range of polyolefin let-down resins. A 60% white concentrate gives better rheology, whiteness, dispersion, and screen life in blown film, cast film, and extrusion coating, with all ingredients acceptable for food contact in North America. White PE MB9 is a 50% titanium dioxide concentrate in LDPE with similar food-contact acceptability, giving high opacity in film and coating, particularly for resins with melt indices higher than 5. Ampacet has also introduced a range of controlled rheology white masterbatch (11989-1), for blown and cast film and extrusion coating. New masterbatches for Dow's new Affinity polyolefins have been introduced, plus a new generation of EBS-based anti-slip/anti-block masterbatch, for high EVA content resins. Surface-treated Ti02 (TiOna, from SCM Chemicals), has an organic surface treatment which is said to give superior colour and processing stability with easy dispersion at high concentrations. It is particularly designed for polyolefins, but there is also a grade for PVC. New from Schulmann is the NG range of white film masterbatches, designed to minimize lip deposits. A Ti02 grade especially for use in masterbatches for production of film and flexible packaging, resisting die build-up, has been introduced by Tioxide under the name Tioxide TR2 7. Intended for high technical performance at the most extreme temperatures necessary for high throughput in production of thinner film, it has been designed to minimize emission of volatiles, so significantly reducing problems such as die build-up and (in extreme cases) lacing. Ease of dispersion into the polymer matrix results in significantly higher levels of throughput. Other advantages include high levels of brightness, colour, and opacity. A new white from Cabot is Plaswite PE7474, to help overcome die deposit in white film production. MFI is l l g (10 min)~^ at 2.16 kg/190°C, giving easy dilution. It is formulated to be compatible with a wide range of polyethylenes, either pre-blended or added direct at the hopper.

84


7.2 Black Pigments Table 7.7 At a glance: black pigments Function

Black pigmentation, high absorption of light

Properties affected

Colour; carbon black also has useful anti-static properties, can provide electrical conductivity; black pigments also give effective UV screening; also used as a reinforcement in rubber compounds (the largest overall use)


Carbon black: different types according to manufacturing process, giving a wide range of particle sizes and shapes, governing the application. Black antimony sulphide is interesting as it is also a flame retardant

Disadvantages

High potential to contaminate other materials/equipment unless kept separate or used in dust-free/non-polluting form

New developments

Improvement in stability, dispersability; forms for easier use/faster mixing; large use of masterbatch forms

7.2.7 Types of carbon black

Carbon black might be described as an ideal universal additive: it can provide pigmentation, reinforcement, ultraviolet shielding, and anti-static properties but always provided that the final colour is black. It is used in several different forms, produced by different production processes for its various applications. There are about 100 different grades today, each of which is matched to an individual application. In thermosetting resins, most carbon blacks tend to inhibit cure and should be avoided. The major user of black is the rubber industry, particularly for tyres, where addition of carbon black contributes to reinforcement and resistance to tearing, abrasion, flex, and fatigue. In the USA it is estimated that a little less than 0.5 lb (0.25 kg) of black on average is used for every 1 lb of rubber used. Plastics are the largest and fastest-growing non-elastomer use for carbon black. A number of production processes are used, of which furnace black is by far the dominant process, accounting now for 9 7 - 9 8 % of total world production (of approximately 6 million tonnes a year). Production processes come under two main classifications: • •

thermal oxidative decomposition (furnace black, Degussa gas black, lampblack, from coal tar or petrochemical-based aromatic oils, natural gas, and coal tar distillates); and thermal decomposition (thermal black and acetylene black, using natural gas or oils, and acetylene; an electric arc process has been used in the past but is no longer commercially significant).


85

7.2.1.1 Thermal oxidative decomposition processes Furnace black is the newest but also overwhelmingly the predominant process. Liquid feedstock is atomized, sprayed into a flame inside a ceramic-lined furnace, and then quenched, cooled, and filtered. The process offers technical and economic advantages, with the facility to produce a wide range of types, with adjustment of particle size and specific surface area. Particle aggregation can also be controlled by addition of very small amounts of an alkali metal salt. Particle size ranges from 10 to 100 [im. Black made by this process has a very low bulk density and is difficult to handle in this form. It is therefore pelletized or further densified. Wet-pelleting enables carbon black to be converted with water

Typical Performance Properties of Carbon Blacks

rger

Particle Size & Properties

A

^^R Higher

Structure & Properties

lighter

Masstone

• darker

higher

V'isc924

V-0 640

19

30

26

25

26 19 1200 8 No break

15 0.8 3800 6 23

21 4.2 1600 3 30

21 3.5 1900 5 No break

Flammability (s - 3.2 mm) UL94 Smoke density (NBS DM flaming mode) L0I(%02) Properties Tensile strength (MPa) Elongation at yield Flexural modulus (MPa) Charpy impact (kj m^^ notched) Charpy impact (kJ m"^) Source: AddconWorld 2000/Eurobrom BV

Modifying Specific Properties: Flammability - Flame Retardants

139

flammability of nylon 6. More recent studies have shown that flame retardancy in many other polymers can be boosted by dispersing clay at the molecular level.


According to the producer Eurobrom BV, the world FR market is worth more than US$2.3 billion, embracing some 1 5 0 - 2 0 0 grades, based mainly on halogens, phosphorus, inorganics, and melamine compounds, and making up about 2 7-31 % of the US$8.6 billion performance additives market. The US and European markets are estimated at about the same (respectively US$758 million and US$800 million per year). In volume terms, researchers BCC and lAL put the US and Western European segments at, respectively, 344 000 tonnes (1998) and 316 000 tonnes (1996). Table 1 0 . 1 4 Consumption of FRs by major region 1989 USA Western Europe Japan Other Asia Total

1992

1995

1998

Average annual growth 1 9 9 8 - 2 0 0 3 (%)

470 332

480 559

585 631

630 685

2.8-3.6 3-4

250 n/a >1052

317 n/a >1356

348 >244 1808

373 >390 2078

3.8 5.1 3.5-4.0

Source: SRI Consulting

Table 10.15 Consumption of FRs by type and region, 1 9 9 8 (thousand tonnes)

Brominated Organophosphorus Chlorinated Alumina trihydrate Antimony oxides Other types Total

USA

Western Europe

Japan

Other Asia

Total

Value (US$ million)

68.3 57.1 18.5 259.0 28.0 42.7 474.6

51.5 71.0 24.7 160.0 23.0 29.8 360.0

47.8 26.0 2.1 42.0 15.5 10.5 143.9

97.0 19.0 20.0 >9.0 >20.0 >83.0 > 165.0

264.6 175.1 65.3 >470 >86.5 > 149.5 1144.5

790 435 116 260 327.5 n/a 2078

Source: SRI Consulting

In value terms (%), the main 'families' of FRs are: brominated FRs, 39; phosphorus-based, 23; inorganics, 22; chlorinated, 10; melamines, 6. For the foreseeable future, the largest single flame retardant material will continue to be alumina trihydrate, with a moderate growth rate of 3.1% a year, but continuing to offer the most cost-effective system. Other types, particularly brominated compounds, will show stronger growth rates. Roskill estimates that

140


world production of brominated FRs is growing at an average rate of 8% a year. FRs now represent the largest single use of bromine, accounting for about 30% of total consumption. World production of bromine should reach 468 000 tonnes a year by the end of the twentieth century. Consumption of chlorine-based compounds, however, is depressed (to 2.1% a year) by environmental concerns, but interest in reducing smoke obscuration and corrosion favours use of phosphorus-based compounds. Other FRs (mainly boron-, molybdenum-, and nitrogen-based compounds) will continue to find markets as synergists and partial replacements for higher-priced chemicals. Magnesium hydroxide is attracting interest. Differing pressures will show themselves in the different materials, as legislation for health and safety and the environment comes to bear on consumer and technical products, which use large quantities of engineering thermoplastics. • • • • • • •

Polyolefins: the market is for non-blooming, non-plate-out types; there is also a demand for non-halogens and improved thermal stability. Styrenics: demand is for non-halogens for ABS and high-impact polystyrene; there is movement away from resorcinol diphosphate in PC/ ABS blends. Engineering thermoplastics: the need here is for high thermal stability driven by need for miniaturization; non-halogens; there is wider use of polymer blends for FR performance. PVC: there is increased concern over smoke generation; better lowtemperature flexibility is required in wire and cable. Thermosets: non-halogen PCBs are now made to FR-4; higher heat distortion temperatures. Polyurethanes: compatibility with CFC replacements is needed, and nonDPO-basedFRs. Phosphorus: interest in reducing smoke obscuration and corrosion favours use of phosphorus-based compounds, which, with a growth rate of 7.0%, will become the third-largest FR additive.

CHAPTER 11 Modifying Specific Properties: Conductivity - Antistatic/Conductive Additives Although it consumes only about 5-7% of plastics, the electrical and electronics market sector exercises large demands on additives, which will certainly grow in volume and value. Covering both consumer and industrial products, 'E and E' involves housings and enclosures for all types of equipment and an increasing volume of moulded connectors and circuitry. Insulation and sheathing for wire and cable, with its own specific demands, can also be included. As well as the stabilizers and processing aids required for most massproduction moulded components, E and E has a significant and growing sector where some form of positive conductivity is needed (at the least, to prevent internal static discharge, but increasingly to shield delicate components against external electromechanical interference).

Table 11.1 At a glance: anti-static/conductive additives Function

Reducing/eliminating the tendency of plastics to retain an electrostatic charge, by providing a surface layer (often activated by atmospheric moisture) or establishing a conductive network within the plastic compound.

Properties affected

Attraction of (especially) lightweight plastics (films, fibres, etc.) to each other and to other materials; improved operation of high-speed machinery (e.g. for packaging); shielding equipment against electromagnetic interference; reduction/elimination of spark hazard in handling electronics, chemcials, medical equipment.


Liquids: quaternary ammonium, polymeric anti-statics. Solids: carbon black, coated metal particles, glass spheres. Intrinsically conductive polymers: polyanilines.

Disadvantages

Possible effect on surface, limiting finishing treatments (e.g. printing); susceptibility to moisture.

New developments

Improved conductivity at lower addition levels; better/more uniform dispersability.

142


The development problem is how to impart long-term and even permanent anti-static properties, without the possibility of migration or leaching. A polymer solution may be the way. A vital requirement for effectiveness is limited compatibility (solubility) with the host polymer and controlled mobility (rate of diffusion) in the matrix. For polymers with a low glass transition temperature (such as polyolefins), continuous migration of the anti-static agent is important to achieve the desired effect, while for polymers with a glass transition rate considerably above ambient temperature (such as PVC, ABS, and polystyrene), the decisive factor is the compatibility at the moment of cooling. A wide range of additives can be compounded into both thermosetting and thermoplastic composites to produce the required degree of conductivity, including reinforcements (such as fibres of carbon or metal, or metallized fibres) or powders. Table 11.2 Classification of electrical insulation/conductivity Surface resistivity (^/sq)

Type of material

10^4

W W

Insulative plastics

W IQi"

10^ 10« 10^ 10^ 10^

Dissipative composites

10^ Conductive composites 10^ 10 10-1 10-^ 10-^ 10-4

ESD shielding composites (carbon powder/fibre)

10-

Metals

Antistatic agents are added to plastics before or during processing. In many plastics they migrate continuously to the surface, where a deposit of the material may occur, even if it is frequently removed. Possible interactions with the polymer must be borne in mind when choosing the anti-static additive (such as lubrication, haze, and effects on thermal stability). Some grades of anti-static agents must not be discharged into waste water but, if handled correctly, anti-static agents are available that present no problems. Suitable grades are also available that comply with most food regulations.

Modifying Specific Properties: Conductivity - Antistatic/Conductive Additives

143

11.1 Classification of Antistatic Additives

Antistatic additives can be classified by application method, as internal and external, and by chemistry, as anionic, cationic, and non-ionic. Internal agents are normally compounded at 0.1-3.0% by weight and have a slight compatibility with the polymer, but the molecule has a hydrophilic head forcing it to migrate to the surface and attract moisture from the environment, which increases the surface conductivity. These are easy to use and have low addition rates, often also providing other benefits such as improved processability and mould release. External additives are basically the same type of molecule, but are applied to the surface of the processed product, as a water- or alcohol-based solution, by spraying, wiping, or dipping. They have immediate effect but are susceptible to accidental removal and the anti-static effect cannot be reinstated. The main cationic anti-static agents are alkyl ammonium salts, with a long molecular chain giving good compatibility with the polymer. They are widely used with PVC, but tend to be heat sensitive. Other anti-static agents are glycerol stearate, acid esters, ethoxylated amines, and others, which act by migrating to the surface, attracting moisture and ions from the air, and so setting up a conductive path to dissipate static charges. Anionic anti-static agents are usually alkali salts of alkyl sulphonic and sometimes phosphonic or carboxylic acids. Sodium alkyl sulphonates are recommended for styrenics. Non-ionic anti-static agents are the most important group, comprising ethoxylated alkylamines or amides, fatty acid esters, and esters or ethers of polyols. Glycerol monostearate (GMS) and ethyloxylated amines (EA) make up more than 50% of the total classical anti-statics market. They are mainly used in polyolefins and styrenics. There is a further class of non-ionics based on amides that overcomes the corrosiveness of EA, which can harm packaged goods. Permanent anti-static additives have been the subject of much development, including highly conductive fillers such as carbon black and incorporation of intrinsically conductive polymers such as polyaniline and polythiophene. While being effective, these suffer from disadvantages in their effect on colour and limited solubility. Special care is needed during processing to build up an antistatic network throughout the polymer, processing at a temperature higher than the melting point of the additive.

11.2 Conductive Additives

Conductive additives usually come in granular or fibre form, offering a wide range of conductivity, according to their nature and the level of loading. Compatibility with the host polymer is a key criterion, as is processability. In conjunction with FRs, they are now a key sector for E and E applications, where they come under increasingly strict regulation regarding performance and evolution of fumes, while the proposed extension of recycling legislation in

144


Europe to cover Waste Electrical and Electronics Equipment (WEEE) is proving a point of serious controversy throughout the industry. Thermoplastics have high resistivity (typically 10^^-10^^ ^ ) and are receptive to build-up of static electricity. The most familiar manifestation of this is attraction of dust to the surface of a plastics product. Among the more serious consequence (in ascending order) are: impairment of the operation of fast machinery such as flexible packaging machinery, electric shocks, and discharge as sparks - which can have catastrophic results in areas where there is risk of the presence of explosive gases. In compounding for anti-static properties, the easiest solution is to add carbon black, which makes the plastic more or less electrically conductive (but also makes it black). Where feasible it is used, and most 'conductive' compounds are based on carbon black. For most electrical applications, there are two types of compound, related to performance, discussed below.

11.3 ESD (Electrostatic Discharge) Compounds

These compounds have a resistivity in the region of lO^'-lO^^ ^ / s q and are designed for use where slow and controlled dissipation of static charges is required. EMI shielding compounds, for protection of electronic components from electrostatic discharge, offer a surface resistivity of lower than 10^' ^/sq, with volume resistivity of lower than 1 Q cm and up to 5 5 dB attenuation. Compounds dissipate a surface charge and can be processed by normal thermoplastic methods. Typical applications are boxes and in-plant handling containers for electronic components or chemicals where there is a risk of explosion from a spark. Medical products also increasingly have ESD specification, especially for use in an operating theatre. Packaging products such as flexible films also require some form of anti-static treatment, either by means of an additive, or by using external field generators.

11.4 EMI (Electromagnetic Interference) Compounds

These compounds screen out undesirable electrical frequencies by means of additives which form a shield. Typical applications are housings for equipment vulnerable to EMI. Because of the nature of the additive shield, they may require special processing, but better understanding of the technology is leading to development of formulations that are compatible with injection moulded thermoplastics, such as ABS.

11.5 Metallic Additives

EMI shielding compounds based on stainless steel fibres are supplied as masterbatch compounds that can be added at low levels, ensuring minimal effect

Modijying Specific Properties: Conductivity - Antistatic/Conductive Additives

14b

on colour and processability. The compounds are non-abrasive and can be pigmented. Shielding levels of 50 dB can be obtained with 1% addition of fibres, by volume. With the widespread use of clean room systems for manufacturing and packaging critical products (such as medicals and pharmaceuticals) there has also been growing interest in improved materials for construction and fitting out. The specialist formulator TBA Electro Conductive Products caters for this need with its new ECP 2000 static dissipation series, designed for 'clean room' applications where the need is for washability, low off-gassing, and low particulate contamination. Offered in a range of polymer matrices, the formulations are permanently conductive and can be moulded on standard equipment, in colours. Potential applications include packaging for medical products, in-process carriers, fixturing devices, chip rails, vacuum tubing, and machinery components. Extremely thin-drawn filaments of stainless steel have been developed by Bekaert under the name Beki-Shield, meeting EMI and ESD specifications at very low loadings. Maximum effectiveness is reached at about 15% by weight. The mechanical and physical properties of the plastic are only minimally affected and

Figure ILL. Carbon black additives can also conduct electricity, ojjeriny a simple and effective means of providing anti-static properties or EMI shielding. (Photograph: Cabot Corporation)

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it is claimed that designers have the same freedom as when working with the original resin. While not used as reinforcement, the fibres can be used with reinforcing fibres without degrading conductivity. In a plastics compound they create an electrically conductive network in the moulded part. The fibres are available as a continuous bundle and in chopped fibre form. The latter are bound with polymeric binders specific for various resins, forming concentrates of stainless steel fibres, designed for easy dispersion into the matrix. Dry blends or melt compounds with the fibre are also available worldwide. Work on metallic additives has been particularly to the fore in Japan. A process to produce very fine metal fibres has been developed at the Nippon Institute of Technology (NIT), Saitama, Japan, and has been commercialized in a joint venture with NV Bekaert, Belgium, under the name Bekinit KK. Described as coil shaving, it is faster and more versatile than traditional methods. Fibres of 2 0 100 Jim in diameter can be produced from titanium, aluminium, nickel, copper, and stainless steel, which offer improved conductivity in plastics compounds. Filter media, heat-resistant fabrics, and motorcycle silencers are among other potential applications.

Figure 11.2. Carbon black particles. (Photograph: Cabot Corporation)


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Table 11.3 Performance of stainless steel fibres at various loadings Vol.% fibre

Weight % fibre

Volume resistivity (^cm)

Performance (30-1000 MHz range of shielding)

0.25-0.5 1.0 1.5 >1.5

4 8 12 15

2 0.5-2 0.1-0.5 60 dB EMI shielding

Source: Bekaert

Table 11.4 Comparison of different conductive systems

Loads for comparable ESD behaviour (wt%) Cost of part Reinforcement Reduced impact strength Moulding Colour Influence on shrinkage Riskofwarpage Emigration of carbon (sloughing) Toxic contamination

Carbon black

Pitch carbon fibres

PAN carbon fibres

Stainless steel fibres

40

20

15

5

Low No Somewhat Reduced Black only Small Small High High

Medium Yes Yes Reduced Black only High High Medium High

Medium Yes Yes Reduced Black only High High Medium Low

Medium No No No influence Colours possible No No No Low

Source: Bekaert

11.6 Coated Polymers

A process for coating synthetic fibres such as polyester and nylon and also natural fibres including cotton with metal to produce a shield against electromagnetic radiation (EMR) has been developed by Daiwobo Co, Japan. Using a palladium catalyst, the coating is a film of copper or nickel less than 1 ^m thick. It costs about 25% as much as silver-plated fibres and provides shielding up to 99.9% of EMR over the range of frequencies from 30 MHz to 30 GHz. It is being sold for applications in cellular telephones and personal data devices. Conductive systems are a fast-growing group of speciality thermoplastics and thermosets, but they have disadvantages, particularly in compatibility, processing with the required high loadings, and reduction in mechanical properties. However, the use of inherently conductive polymers (ICPs) - also known as synthetic metals - is generally limited by their poor thermal stability (usually up to about 180°C). A solution that addresses both deficiencies could be a high-performance conductive filler that is produced by polymerization deposition of a coating of an ICP onto the surface of carbon black particles (which are also conductive).

148


Developed by Eeonyx, USA, it is claimed that conductive blends can be produced in a number of polymer matrices with improved electrical and mechanical properties. Melt flow and compounding are improved, with easier end-product fabrication. For example, in some systems (such as ABS, nylons, and polyesters) only half as much of the additive is needed to achieve the same conductivity level as a typical carbon black loading. The coated particles possess greater thermo-oxidative stability than ICPs (300-3 50°C), so accommodating the majority of thermoplastics and thermosets currently used in industry without degradation or loss of conductivity. The filler has a greatly reduced surface area and pore volume compared with the original carbon black. In a number of plastics matrices, conductive blends can be produced with improved electrical, and mechanical properties.

11.7 Intrinsically Conductive Materials

Several companies have developed intrinsically conductive polymers. Notable is a range of conductive dispersions based on ICPs such as polyaniline and polypyrrole, developed by DSM and marketed under the name ConOuest. The first commercial applications are emerging, and the company claims to have overcome the problem of poor processability in common solvents by using a dispersion of a conductive polymer and a waterborne binder resin. This uses only a low percentage of the conductive polymer and, as the functional part is located in the optimal position, the coating is more cost effective. The carrier system - basically a polypyrrole shell and a polyurethane carrier resin - can be modified by changing either component. A range of additives based on polymeric or inorganic powders has also been developed which could be used as alternatives to carbon black to achieve 'tuneable' conductivity or avoid contamination. Mechanical properties are relatively good due to the low loading required. At very thin layers, the coating can be more transparent than is usually observed with standard polypyrrole systems, because the high conductivity is obtained with only a low amount of polypyrrole. There is a relatively high absorption of infra-red radiation. At a layer thickness of 2 jim visible light transmission is 90%, reflecting 35% of infra-red radiation. At higher layer thickness, close to 100% reflection can be achieved. A possible application might be for treatment of camouflage netting.

11. 8 Moulded Circuitry

Given that some basic technical problems can be overcome, metallic additives have an exciting future with the possibility of moulding the complex electrical and electronics circuits in electronics equipment, as are used now in automobiles, rather than using printed circuitry. While printed circuits go a long way, the next stage is to mould three-dimensional circuitry, and mixing metallic


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particles into the compound makes it possible to build the circuitry into the components while they are being moulded. There has been some work aiming at using standard injection moulding equipment and the project has been assigned to Sinto Kogyo for further development.


Some recent applications illustrate the present scope of conductive additives. A non-migrating LDPE-based carbon black compound (Cabelec 4540) is combined with additives that facilitate opening and sealing of conductive bags for electronics components. The special carbon black absorbs only little moisture and so does not usually need to be dried before processing. Bags made from the compound can be used for packaging explosive powders, pigments, and other products needing to be protected from static discharge. The typical tensile strength is 19.4 MPa and elongation at break is > 550%. The typical surface resistivity on 100 jim film is 10 ^ ^/sq. An innovative carrier for semiconductor wafers designed in the USA is made of two polymers: polycarbonate over-moulded with a speciality conductive PEEK compound from RTP. The polycarbonate base gives dimensional strength at a low cost, with transparency and toughness (clear, red, blue, or green tints provide easy identification from all angles), and the conductive PEEK overmoulding provides an electrical grounding path and protective lining for the carrier in areas where it may come in contact with a wafer or production or handling equipment. Although the usual carrier in masterbatch systems is LDPE, electrically conductive compounds have been introduced based on polypropylene and polyacetal. Cabot's Cabelec 3898 is a PP compound that is particularly suitable for the production of corrugated sheets used for packaging of products (such as electronics components) that are sensitive to electrostatic discharge. It is said to show an excellent balance of rigidity and impact strength. It offers particular advantages to the sheet extruder by non-hygroscopic behaviour, easy processability (close to nonconductive PP grades) and ability to reuse production scrap without loss of the conductive properties. The acetal compound Cabelec 3899 is suitable for injection moulding and is designed, typically, for applications such as automobile fuel inlets, where permanent conductivity, coupled with good dimensional stability, is increasingly required to reduce explosion hazards. For greater durability, Croda is offering amine-free, long-term anti-statics (for applications in sensitive electronics packaging), using materials that have never been used for this purpose before. The additives are also thermally stable and suitable for use in a wide range of polymers. Permanent anti-static properties are claimed to exist in certain grades of Elf Atochem's Pebax polyether block amide engineering copolymers, which has led to their use as additives in ABS and other thermoplastics. In some cases it has been found advisable to include a compatibilizing agent. Pebax MV 1074 and MH 1657 have surface resistivities

150


lower than 3 1 0 ^ ^ cm~^ under the ASTM D 257 standard, and a half-discharge time of less than 1 second. In concentrations of 5-10%, they can impart permanent anti-static properties to the matrix polymer, effective across a wide range of moisture levels and in the event of abrasion of the moulded product. They have no effect on colour or on the flexural modulus of the host polymer, and will not migrate. They also possess excellent thermal stability, breaking down at above 400°C - well above the processing temperature of most thermoplastics. A system developed by Ciba in its Irgastat range is based on the principle of hydrophilic copolymers in which additive filaments form a percolating system, with diameters of 0.2-15 |Lim. These are used mainly in styrenics and acrylics but, for polyolefins, high loadings of up to 30% would be required, while mechanical properties are significantly changed. The latest developments, however, point towards systems that are also suitable for polyolefins, with a larger processing 'window' to include low-density polyethylene blown film. These grades are colourless, migration free, show no deterioration of the surface, and are effective at very low relative humidity. Very pure superconductive carbon blacks are produced by Akzo Nobel under the name Ketjenblack. Due to their unique morphology, substantially lower amounts can be used compared with conventional blacks, giving improved processing and mechanical properties for electroconductive products. High concentrates of anti-static, slip, and anti-blocking additives on a polymer carrier are offered by Akzo Nobel, using its Nourymix patented technology. They have uniform granular form and are easy to handle and pre-mix with polymers.

CHAPTER 12 Modifying Processing Characteristics: Curing and Cross-linking Table 12.1 At a glance: curing systems Function

Effecting cross-linking of thermosetting resins: initiation of reaction, control of speed of reaction.

Properties affected

Resin production: fundamental to development of desired mechanical and chemical properties.


Organic peroxides. Cobalt/amine/vanadium compounds. Aliphatic amines. Ketones, anhydrides, etc.

Disadvantages

Special precautions required in storage and use: danger of lire, health and safety precautions must be observed.

New developments

Improved stability; better formulations for health and safety in the workplace.

12.1 The Curing Process

Thermosetting resins differ fundamentally from thermoplastic resins in that they are prepared for processing in an uncured state, and they are cured during the processing stage, by the application of heat with the assistance of chemical agents, in a once-only reaction. This makes them (usually) hard and infusible, with relatively good resistance to heat. Cross-linking is also an important, but highly specialized, sector of thermoplastics processing, especially for the production of wire and cable sheathing. Curing agents are therefore an important group of additives that influence curing: they can initiate the cure by catalysing and promoting, or can control the cure by accelerating or retarding it. Thermosetting resins are processed by means of a change in their molecular structure, in which, under certain circumstances, the individual molecular chains can be made to link up in an irregular fashion, forming a solid infusible network. This is called 'curing', and will happen, in time, by normal processes (in fact, it was this phenomenon which first attracted the interest of researchers in the last century). For industrial purposes, curing (or 'cross-linking') can be activated by means of special chemicals, heat, or irradiation.

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12.2 Terminology

Several different terms are used in the industry to cover curing agents: 'catalyst' (not technically accurate, but widely used), 'hardener', or 'initiator'. 'Activators' (also called 'promoters' or 'accelerators') are used to speed up the cure. 'Inhibitors' perform the opposite function.

12.3 Curing Agents, Accelerators

Peroxides are used as catalysts for unsaturated polyester resins, generating free radicals and causing cross-linking, acting at either elevated or ambient temperature. Development of peroxide and peroxyester systems for room temperature curing of thermosets is a priority. Curing of polyurethane systems requires a balance between control of the isocyanate/polyol reaction (causing cross-linking) and isocyanate/water reaction (causing foaming). Replacement of CFCs must also take this into account. Polyester resins are usually cured by addition of special chemicals that decompose to free radicals, offering a simple technique that can easily be controlled, regarding rate and length of cure. Polyester resins can also be cured Table 12.2 Applications of organic peroxides A Cross-Uukinfi PE CM EAM EPM EKM VMQ SBR Curincj Contact moulding Rotational casting Continuous processing Press moulding Casting Coating Wood varnishes Wood impregnation Other Styrenation Graft copolymers PP degradation Furane curing Flame retardancy Additives Source: Peroxid-Chemie

B

C

X

D

E

X

X

X

X

X

X

X

X

I

J

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

F

G

H

K

X X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X X

X

X

X X

X X

X

X

X

X X

X

X X X

Modifying Processing Characteristics: Curing and Cross-linking

153

by heat or irradiation and newest technology is to offer resins that cure under the effect of UV. The usual chemical curing agent is an organic peroxide, which is a more or less stable chemical compound comprising carbon, hydrogen, and oxygen, easily decaying in extremely active radicals. For curing polyester resins, a wide range of organic peroxides is available for various thermal stability requirements, ranging from compounds which decompose rapidly to free radicals at ambient temperature to those active only at higher temperatures. The former are not normally used for curing unsaturated polyester resins. More often used are peroxides that are stable at ambient temperature and decompose at 50-150°C. At ambient this is not sufficiently active to cure the resin, and reducing agents such as tertiary aromatic amines, heavy metal salts of cobalt, vanadium, and iron are used to accelerate decomposition. Organic peroxides are derivatives of hydrogen peroxide. They can be used to initiate a polymerization reaction, and influence the quality and final properties. In the context of additives, they can be used to cure unsaturated polyester resins, and cross-link thermoplastics (such as polyethylene and EVA) and elastomers. There is a very large number of different types. They are produced in liquid form and as masterbatch, in powder and granule, paste, and flake, and as dispersions. Persulphates (inorganic diperoxysulphates of ammonium, potassium, and sodium, and triple salt potassium monopersulphate) are used as initiators in the polymer and fibre industry, as weU as other applications in other industrial sectors. Table 12.3 Cross-linking with peroxides: dosage of peroxide per 1 0 0 parts polymer Polymer

Perketale

Dicumyl

Di-benzene

Dimethyl hexane

Polyethylene Chlorinated PE Ethylene vinyl acetate Natural rubber/isoprene Polybutadiene Chloroprene Styrene/butadiene Ethylene propylene/EPDM Cross-linking temperature (°C) Manufacturing temperature (°C)

1.5-7.5 6.8-10.5 2.6-5.2 2.3-4.6 1.0-2.0 1.1-3.0 1.9-4.0 6.9-11.0 150 110

1.4-6.6 6.1-9.4 2.4-4.5 2.0-4.0 0.9-2.0 1.0-2.6 1.7-3.6 6.0-10.0 170 120

0.8-4.0 3.8-5.8 1.5-3.0 1.3-2.4 0.5-1.1 0.6-1.6 1.1-2.2 3.8-6.2 180 130

1.2-6.3 5.7-9.1 2.2-4.4 1.9-3.8 0.8-1.8 1.0-2.6 1.6-2.4 5.8-9.5 180 130

Source: Perg an

12.4 Inhibitors

Compounds that prevent undue polymerization of the resin are called inhibitors, typically monohydric or polyhydric phenols and some quinones. They are usually added during manufacture of the resin to ensure stability in storage.

154


They can prolong the pot Ufe of a resin system containing peroxide and accelerator, particularly with cobalt systems. Inhibitors can also influence the ratio of cure to gel time, as they mainly prolong gel time. p-^Butylcatehol extends gel time and pot life at room temperature and at elevated temperatures; 2,6-di-t-butylparacresol is used with BPO/amine systems, to give lower peak exotherm and gradual cure.

12.5 Curing with Accelerators

Use of accelerators to aid curing is the most popular method: curing is possible at below 100°C with organic peroxides in combination with accelerators, or preaccelerated resins. Post-curing at 80-120°C is normally required. The normal curing system is a ketone peroxide (based on either methyl ethyl ketone, cyclohexanone, or acetyl acetone) with cobalt octoate or naphthenate. Alternatively, diactyl peroxides such as benzoyl peroxide are accelerated with diethylaniline, dimethylaniline, and dimethyl-p-toluidene. Amine acceleration gives a fast curing cycle but can produce tackiness in thin layers and very strong discolouration during ageing. A ketone peroxide with cobalt acceleration therefore forms the most popular curing system. • • • •

Cobalt: cobalt octoate (mainly used with ketone peroxides for polyesters at room and elevated temperatures); Amine: dimethylaniline with dibenzoyl peroxide at room temperature, normal/long gel times), dimethyl-p-toluidine (very short gel times); Cobalt/amine: very high reactivity with ketone peroxides for very fast cure (for example, polymer concrete); Vanadium: special for ketone peroxide, hydroperoxide, and peroxy esters, giving short gel times, and very high cure speed.

12.6 Curing without Accelerators

Without use of accelerators, external heat is required, making a system suitable for mechanical processes, such as hot press moulding and continuous impregnation of sheet and profile. Temperatures in the range 120-160°C are used to cure in a short cycle: accelerators offer no advantage as the rate of cure depends on thermal decomposition of the peroxide, and typical cycle times are 1 10 minutes. Usually a combination of long shelf life of the uncured compound with short curing cycle is required, calling for adequate thermal and chemical stability. Organic peroxides for high temperatures are peresters and perketals. Low initiation temperature with adequate curing performance is given by dimyristyl peroxy dicarbonate or methyl isobutyl ketone peroxides (in the latter case limiting shelf life to a few hours). Combinations of peroxides can be used: the more active types reduce initiation temperature while more stable types give a better degree of cure.


155

12.7 Selecting a Curing System

A number of factors must be considered in processing conditions, in descending order of importance: • • • • •

high-output production; batch or continuous process with/without external heat; moulds closed or open to air; required shelf life of the activated compound: immediate/days/weeks/ months; possibility of using resin + peroxide and resin + accelerator as separate components in a 'two-pot system'.

Thick-walled castings or thermally insulated mouldings, which can reach a peak exotherm of over 200°C, producing cracks from internal stress or shrinkage, can be moulded better with less-active curing systems. Surface coatings (with no exotherm and slow cure with possible air inhibition) can better use very active curing systems. Where colour is important, accelerators must be kept to a minimum: amines are not suitable, ketone peroxides/metal salts are preferable.

Table 12.4 Curing systems and w h e n / w h e r e to use them Type/form

Main characteristics

Ketone peroxides for 'cobalt curing' at ambient temperatures Methyl ethyl ketone peroxide: Standard for all resins, including bisphenol liquid, high activity and vinyl esters; relatively short gel times, moderate heat evolution, little internal stress

Processes A, B, c, D, E, f

Liquid, low activity

Versatile type for all resins, particularly vinyl esters; relatively long gel times, short mould release times; good for large parts and/or use in hot countries

A, c, D, E, G

Liquid, superactivity

Special for buttons/button sheets

a,b,d, e,f

Acetyl acetone peroxide; liquid, normal activity

Versatile type for ortho-or isophthalic-based resins; relatively short cure time, strong heat evolution; suitable for thin-wall mouldings

a,B,C,d,F,G


Specialfor thick-wall mouldings; variable gel times, reduced peak exotherm, short mould release times

a,b,c


Special for very thick-wall mouldings; relatively long gel times, little heat, acceptable mould release times

a, b, c

Cyclohexanone peroxide; Uquid, normal activity

Versatile type for nearly all resins; variable gel times, moderate heat, little stress; suitable for large or thick-wall mouldings

a

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Type/form


Processes

Liquid, high activity

Versatile type for nearly all resins (also vinyl esters); variable gel times, relatively short mould release times, reasonable mould release factor

a,b,C,E

Benzoyl peroxide for 'amine curing' at ambient temperatures Dibenzoyl peroxide: 50%, Rapidly dissolving in all resins, include, bisphenol a, b, c, g powder with phthalate A and vinyl ester; variable gel times, strong heat evolution, relatively short mould release times; no accelerator required above 70-80°C 50%, suspension

Pourable/pumpable suspension, dissolves rapidly; curing performance as above

a, b, c, G

40%, suspension

Pourable/pumpable suspension, dissolves rapidly; special type for easy dosing/metering; curing performance as above

a, b, c, G

Organic peroxides for curing at 60-120° C Dimyrstylperoxy dicarbonate: Special type for curing above 50°C, but only with techn. pure, flakes more thermally stable peroxides; suitable for all resin types

f

Methyl isobutyl ketone peroxide: liquid, normal activity

Versatile type for curing above 5 5°C, possible with e, f more thermally stable peroxides and/or cobalt accelerators; suitable for all resin types

t-Butylperoxy-2-ethylhexanoate: techn. pure, liquid

Versatile type for curing above 7()°C, possible with more thermally stable peroxides and/or cobalt accelerators; suitable for all resin types

f.g.h

Dibenzoyl peroxide: 50%, power with phthalate

Versatile type for curing above 7()°C, possible with more thermally stable peroxides and/or amine accelerators; suitable for all resin types

U

Cumene hydroperoxide: 80%, liquid

Special type for curing above 8()°C, with cobalt accelerators

1,1 -Di(t-butylperoxy) trimethyl cyclohexane: liquid, high activity

Versatile type for curing about 80°C; 'quick-set' in range 120-15()°C for hot press moulding SMC or BMC; can be accelerated by promoters

F,G,H

50%, solution in aliphatics

Special for SMC/BMC at 130-160°C without accelerator; not sensitive to fillers, pigments and promoters

g,h

1,1 -Di(t-butylperoxy) cyclohexane: Standard for SMC/BMC at 130-160°C without 50%, solution in alphatics accelerator; not sensitive to fillers, pigments and promoters

g.H

t-Butylperoxy benzoate: techn. pure, liquid

Standard for SMC/BMC at 130-160°C; can be accelerated by promoters; sensitive to some fillers and pigments (e.g. carbon black)

50%, powder with chalk

Standard for granulated moulding compounds at 130-160°C without accelerator; can easily be mixed in as free-flowing powder


Type/form


t-Butylcumyl peroxide: techn. pure, liquid

Special for SMC/BMC with deep flow at 130-160°C; not sensitive to fillers, pigments and promoters

1,3-Di(t-butylperoxy isopropyl) benzene: tech. pure, flakes

Special for granulated moulding compounds at 140-1 70°C without accelerator; not sensitive to fillers, pigments and promoters; also available as 40% powder with chalk

Accelerators Cobalt octoate: in phthalate with 1% cobalt

157

Processes

h,I

Standard for ortho- or isophthalic acid resins with ketone peroxides or peresters; gel and cure times vary according to peroxide; 20-100°C

In xylene with 6-10% cobalt

Special for large batches or high usage; can be diluted; performance as for above

A,B,C,D,e, f.g

Cobalt octoate/dimethyl aniline: liquid mixture in phthalate

Special for bisphenol-A or vinyl esters, with ketone peroxides or peresters; short gel/cure times; 10-100°C

a,b,c,d,E,G

Dimethyl-p-toluidene: 10% solution in phthalate

For short gel/cure times with dibenzoyl peroxide; suitable for all resins; 10-1 ()()°C

a, c, G

Dimethyl aniline: 10% solution in phthalate

For medium gel/cure times with dibenzoyl peroxide; suitable for all resins; 1 5-10()°C

a, b, c, G

Diethyl aniline: 10% solution in phthalate

For long gel/cure times with dibenzoyl peroxide; suitable for all resins; 1 5-l()()°C

a, b, c, g

Inhibitors Di(t-butyl)-p-cresol: techn. pure powder, 40% solution in xylene (SETA flash point-30) t-Butylcatechol: techn. pure, powder, 10% solution in styrene (SETA flash point-31)

Prolongs up to weeks/months shelf life (gel time f, g, H. of resin + peroxide) at ambient temperature; effect on cure times diminishes with rise in temperature; efficient with many types of resin and peroxide Prolongs up to many hours pot life (gel time of resin + ketone peroxide + cobalt accelerator) at ambient temperature; mould release factor improved; also efficient at elevated temperatures

a, c, d, e, f, g.h,i

Key: upper case letter = very suitable; lower case letter = suitable. A = hand lay-up; B = spray lay-up, C = injection/vacuum forming; D = centrifugal casting; E = filament winding; F = continuous impregnation; G = wet press moulding; H = hot press moulding (SMC/BMC); I = hot press moulding (granular moulding compound).

12.8 Curing Agents for Epoxy Systems

Dicyandiamide, organic acid anhydrides and adipic dihydrazine are widely used as latent curing agents for epoxies. Latent epoxy systems obtained from these hardeners have fairly good storage stability but must be heated at higher temperatures for a long time to establish the curing reaction. To improve curing

158


conditions, accelerators such as aromatic tertiary amines or imidazole derivatives are used, but these tend to reduce the latency, resulting in very short pot life. Liquid aliphatic polyamines and their adducts are convenient to handle and give good physical properties for the cured resin, including excellent resistance to chemicals and solvents. Mix ratios are critical for optimum performance. Aliphatic amides offer fast curing at elevated temperatures, but their short pot life and high exotherm in thick sections or large masses can lead to thermal decomposition. Good long-term retention of properties is possible at temperatures up to 100°C. Short-term exposure to higher temperatures can be tolerated. Aliphatic amines will blush under very humid conditions. Adducted aliphatic polyamines offer the advantages of lower vapour pressure, reduced blush tendency, and less-critical mix ratios. Cycloaliphatic amines give the cured resin improved thermal resistance and toughness (compared with aliphatic polyamines). Glass transition temperatures approach those of aromatic amines and percentage elongation can be doubled. Because they are less reactive than aliphatic polyamines, they can be used to obtain longer pot life and give the ability to cast larger masses. Aromatic amines are solids at room temperature and are routinely melted at elevated temperatures and blended with warmed resin. Eutectic mixtures of metaphenylene and methylene dianiline exhibit a depressed melting point, producing an aromatic hardener that remains liquid over short periods of time. Pot life is considerably longer that that of aliphatic polyamines. Cure at elevated temperature is needed to develop optimum properties, which are maintained at up to 150°C. Aromatic amines have better chemical and thermal resistance than aliphatic polyamines. Polyamides are the most commonly used polyamines. They are the condensation products of dimerized fatty acids and aliphatic amines such as diethylene triamine. A range of molecular weights is available, making these curing agents versatile in a variety of applications. They react with epoxide groups through the unreacted amine functional groups in the polyamide backbone. Due to their relatively high molecular weight, the ratio of polyamide to epoxy is more 'forgiving' (can vary more) than with lower molecular weight polyamines. Polyamides also offer the advantage of curing without blushing, and improved adhesion - but they are much darker in colour. The various molecular weight polyamides show different degrees of compatibility with epoxies. To ensure optimum properties the polyamide/epoxy mixture must be allowed to react partially before being used. This partial reaction assures compatibility and is known as the 'induction' period. Because polyamides have a long pot life, the induction time does not significantly shorten the usable time of the system. Polyamide-cured epoxies lose structural strength rapidly with increasing temperature, limiting their use to applications that will not be subjected to temperatures above 65°C. Amidoamines are derivatives of monobasic carboxylic acid (such as ricinoleic acid) and an aliphatic polyamine. Like the polyamides, amidoamines can be used


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over a range of additive levels to enhance a specific property. The reactivity of amidoamines with epoxies is similar to that of polyamides, but the former offer several advantages over both polyamides and aliphatic amines: lower viscosity and colour than polyamides and more convenient mix ratios, increased flexibility, and better moisture resistance than aliphatic amines. Dicyandiamide (Dicy) is a solid curing agent which, ball-milled into liquid epoxy resins, provides one-package stability for up to six months at ambient temperature. The cure occurs when heated to 150°C; a tertiary amide accelerator is needed for rapid cures. *Dicy' offers the advantage of being latent (it reacts with epoxy on heating and stops reacting when the heat is removed). This partially cured (or 'B-stage') state is ideal for pre-preg applications. Resin systems made from dicyandiamide-cured epoxy have high rigidity and good chemical resistance. Derivatives, such as biguanides, condensation products with aldehydes, and metal complexes can also be used as curing agents for epoxies. Typically, dicyandiamide is used at levels of 5-7 parts per 100 parts liquid epoxy, and at 3-4 parts per 100 solid epoxy resin. It can be used for onecomponent formulations with long shelf life. The moderately high curing temperature can be reduced by adding accelerators such as amines, imidazoles, or urea derivatives. Applications include prepregs and composites, printed circuit boards, structural adhesives, powder coatings, and lacquers and varnishes. Catalytic curing agents are a group of compounds that promote epoxy/epoxy reactions without being consumed in the process. Stable one-package systems can be developed with many catalytic curing agents, such as the boron trifiuoride complexes. Tertiary amines and amine salts have pot lives generally ranging from 2 to 24 hours. The latent catalysts are activated by heat and cause a dissociation of the active catalysts from the blocking group. The amount of catalyst used may vary from 2 to 10 parts per 100 parts resin. To determine the best catalyst/resin ratio, several different catalyst levels should be evaluated for the one giving the best properties. Several common catalytic curing agents are: benzyldimethylamide (BDMA), boron trifiuoride mono-ethylamine (BF3.MEA), and 2-methylimidazole (2-MI). Anhydrides, both liquid and solid, are used widely for curing epoxy resins. The reactivity of some is slow and an accelerator (usually a tertiary amine) is often used at 0.5-3.0% to speed gel time and cure. The optimum amount is usually critical, depending on the anhydride and resin, and the cure schedule. Amounts above or below the correct level will reduce the high-temperature performance. The optimum balance should be established by experiment. Eutectic mixtures to depress the melting points may be prepared. Compared with aliphatic amine cures, the pot life of anhydride cures is usually long and exotherm is low. Elevated-temperature cures at up to 200°C are necessary and long post-cures are required to develop ultimate properties. Electrical and physical strength properties are good over a wide temperature range. Compared with amine-cured systems, anhydride cures offer better chemical resistance to aqueous acids, and less chemical resistance to some reagents. Melamine/formaldehydes cross-link with epoxy resins to give low-colour coatings with good physical properties, chemical resistance, and no effect on

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taste. They will react with epoxide or secondary hydroxyl groups, with varying degrees of reactivity and compatibility. Urea/formaldehydes react in a similar manner, giving exceptionally low colour with good colour retention, hardness, and solvent resistance. Phenol/formaldehyde resole resins cure with epoxies through the secondary hydroxyl groups in the epoxy backbone. Elevated temperatures of above 150°C are necessary to promote cure and use of an acid accelerator is desirable. The resulting systems give hard chemical-resistant coatings, with a wide temperature range. Epoxy/phenolic ratios normally range from 80/20 to 6 5 / 3 5 : increasing the phenolic level improves chemical and solvent resistance, but at the sacrifice of some adhesion and flexibility. Phenol/formaldehyde novolac resins react with epoxy groups at elevated temperatures to give highly cross-hnked systems, with a high service temperature >150°C and excellent chemical resistance. The typical epoxy/ novolac ratio is 0.9 to stoichiometric: a tertiary amine accelerator is necessary for complete cure. Isophorone diamine (IPDA) hardeners are used in epoxy resin formulations mainly for preservation of structures and for composite materials with strong mechanical properties and high resistance to corrosion. The derivative isophorone di-isocyanate (IPDI) is also finding increasing use as a material for light-fast polyurethane coatings.

12.9 Cure Promoters

Cure promoters include metal compounds, for optimal cure hot press moulding; acetylacetone, with ketone peroxides and cobalt accelerator for a short geltime, giving a fast cure at room temperature and at elevated temperature; and tertiary dodecyl mercaptane, for a gradual cure and moderate peak exotherm, in filament winding.

12.10 UV Cure Initiators

UV cure initiators include aromatic ketone, used in printing ink and paper coating; benzoine ether, a general UV cure initiator for FRP laminates, putties and lacquers, particularly effective with fillers; and a mixture of ketones, used with an amine accelerator for UV-curing FRP laminates.


Designed for epoxy resin systems, Anquamine 401 and Ancamide 2424 (by Air Products) are a modified aliphatic curing agent at 70% solids in water for waterborne two-component epoxy coatings; and a modified polyamide curing agent for liquid epoxy resins in two-component structural adhesives.


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Table 12.5 Curing agents for epoxy resins Type

Advantage

Disadvantage

Typical applications

Polysulphides

Moisture insensitive; quick set time; flexible

Odour; poor performance at elevated temperature

Adhesives, sealants

Aliphatic amines

Convenient; cures at room temperature; low viscosity; low formulation cost

Critical mix ratios; strong skin irritant; high vapour pressure; blushing

Civil engineering, adhesives, grouts, casting, electrical encapsulation

Polyamides

Convenient; cures at room temperature; low toxicity; flexibility/ resilience; good toughness

Higher formulation cost; high viscosity; low heat resistance; low vapour pressure

Civil engineering, adhesives, grouts, castings, coatings

Amidoamines

Reduced volatility; convenient mix ratios; good toughness

Construction adhesives, Poor performance at elevated temperature; concrete bonding, some incompatibility trowelling compounds with epoxy resin

Aromatic amines

Moderate heat resistance; good chemical resistance

Solid at room temperature; long cure schedules at elevated temperature

Filament-wound pipe, electrical encapsulation, adhesives

Dicyandiamide

Latent cure; good properties at elevated temperature; good electrical properties

Long cure at elevated temperature; insoluble in resin

Powder coatings, electrical laminates, one-component adhesives

Catalytic

Very long pot life; high heat resistance

Long cure schedules at elevated temperature; poor resistance to moisture

Adhesives, electrical encapsulation, powder coatings, electrical laminates

Anhydrides

Good heat resistance; Long cure schedules good chemical resistance at elevated temperature; critical mix ratios

Filament-wound pipe, electrical encapsulation, adhesives

Melamine/formaldehyde Good hardness/ flexibility; one-pack stability; solvent-free systems

Cures at elevated temperature

Waterborne coatings, primers and topcoats

Urea/formaldehyde

Good film colour; one-pack stability; good intercoat adhesion

Cures at elevated temperature

Fast-bake enamels, primers and topcoats

Phenol/formaldehyde

Solid; poor weather Good properties at reistance elevated temperature; good chemical resistance; good hardness/flexibility

Powder coatings, moulding compounds

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For cationically cured resin systems, new photoinitiators, CD-1010 triaryl sulphonium hexafluoroantimonate and CD-1011 triarl sulphonium hexafluorophosphate, have been developed by Sartomer. Cure enhancers for UV/EB and peroxide-cure systems are low-volatiUty Uquid monomer SR-502 ethoxylated trimethylolpropane triacylate, curing rapidly in systems to increase flexibility, weather resistance, chemical resistance, shrinkage, abrasion resistance, and impact strength, for coatings, PVC flooring, and photopolymers; and CD-501 propoxylated trimethylolpropane triacrylate, for low shrinkage in acrylics, adhesives, coatings, electronics, and photopolymers.

12.12 Thermoplastics Cross-linking

Production of high-performance thermoplastics cable requires cross-Unking, usually by one of three methods: peroxide, silane (Monosil or Sioplas), and electron beam, each requiring a different compound to achieve the right properties. Peroxide cross-linking employs the thermal degradation of a peroxide to form free radicals. These then abstract a hydrogen atom from the polymer, producing a free radical site. Two radicals then combine to produce a chemical bond. The peroxide is usually present in the polymer as supplied and is not added as a separate material. The thermal reaction usually takes place in a hightemperature continuous vulcanization (CV) tube, immediately after the compound has left the extruder die. The residence time of the cable in the high-pressure CV tube determines the extent of the reaction and so dictates the speed of the extrusion line. The temperature in the extruder is also critical, as too high a level will initiate the decomposition of the peroxide and the reaction will start to occur in the extruder. Silane cross-linking - specifically the *one-shot' system - employs a threecomponent mix (of peroxide, silane, and tin catalyst, either in the form of liquid of dry masterbatch) that is added separately to the compound during extrusion. The reaction is in two stages, the temperature of extrusion being used to decompose the peroxide in order to react the silane molecule onto the polymer backbone. This material is then extruded, forming the cable, and the silane units are then hydrolysed together in a secondary stage off-line from extrusion, using moisture and the tin catalyst. Cross-linking can be achieved either by placing the cable drum in a water tank, or in a steam room, or by allowing atmospheric moisture to complete the reaction. Since the cross-linking stage is separate from extrusion, the line speed is determined by the output of the extruder, not the rate of the cross-linking reaction. A dry silane masterbatch for cable extrusion applications has been developed by the Hanna group, Wilson Color. It is claimed to reduce costs in formulation of in-house grafted compounds, providing a route to cost-effective, one-step crosslinked polyethylene cable extrusion. A range of grades is available, to give a broad application 'fit'. Because the active cross-linking agent is in a dry solid


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form, the masterbatch eliminates the need for Uquid injection and can be used in all standard extruders. Other advantages include a higher set-up temperature, which gives higher thermal stability during grafting and extrusion and reduces the risk of plate-out on the extruder screw, producing higher grafting efficiency. The masterbatch maintains the required level of anti-oxidants and metal stabilizer in the final compound, forming a completely homogeneous mix. Special stabilizers prevent premature polymerization. Another technological advance has been the development of cross-linking methods, giving the polymer improved physical properties, better resistance to chemicals, and retention of shape at temperatures significantly above the melting point of the polymer itself, so prolonging its life in the event of a fire. Electron beam curing is similar to peroxide cross-linking, except that no peroxide is necessary. The cable is passed in front of a radiation source that generates radicals on the polymer backbone by removing hydrogen atoms, which then react together to produce a chemical bonding between the polymer chains. The eventual density of cross-linking is determined by the number of passes through the radiation source, and its intensity, so controlling the rate of production. Manufacturers such as BICC General Compounds have developed ranges of halogen-free, low-smoke and low-fume compounds, specifically for manufacture Table 12.6 General specifications for BS7211 Specification requirements Mechanical properties (BS EN 60811) Minimum tensile strength Minimum elongation at break Heat-aged properties (BS EN 60811) Tensile strength: maximum variation Elongation at break: maximum variation High-temperature properties (BS EN 60811) Pressure test at 100°C: maximum penetration Hot set test at 200°C 3°C; mechanical stress, 0.20 N mm~^: maximum elongation Maximum permanent elongation

lO.OMPa 12 5% Temperature:! 3 5°C2°C; duration: 2 days 30% 30% 50% 100% 25%

Low-temperature properties (BS EN 60811) Cold bend at-15°C Cold impact at-15°C Cold elongation at -15°C

No cracks No cracks 30% minimum

Fire test properties Flame propagation, BS 4066 Part 1 Smoke emission, lEC 61034 Halogen acid gas emission, BS 642 5 Part 1 Acid gas emission, BS 642 5 Part 2 Conductivity of effluent gases

50 mm minimum 60% maximum 0.5% maximum 4.3 pH minimum 10 |iS mm~^ maximum

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by any of these three routes. For peroxide cross-Unking, the compound has been selected to maximize the speed of the line by providing maximum scorch safety time during extrusion, while giving maximum residence time in the CV tube. The version for silane processing has been formulated to minimize silane doses and avoid side reactions with the curing system, while the compound for electron beam curing contains special promoters to maximize cross-link density.

Table 12.7 Advantages and disadvantages of available cross-linking methods Peroxide

Monosil

Electron beam

Set-up costs

High: needs expensive CV tube and heating equipment

Low: can use conventional PVC extrusion line

Very high: needs expensive radiation s ource and appropriate safety equipment

Manufacturing speeds

Limited by residence time in CV tube, which determines line speed

Normal extrusion limits: i.e. head pressure and rpm

Limited by exposure time to radiation source, which dictates line speed

Health and safety

Compound contains peroxide

Silane requires special handling and storage

Special controls and procedures needed for radiation source

Other factors

Start-up scrap through the CV line

Requires curing off-line. Can use either ambient cure or water tank/sauna

Short cross-linking time

Source: BICC General Compounds Division


No market figures are available for curing agents, but their size and growth are closely related to the use of thermosetting resins and polyurethanes. The overall technical trend is towards systems that are more rapid and safe in use. A specific area of growth is radiation curing, in which the resin system is cured by exposure to a radiation source. This technique is particularly effective for products that can be cured continuously, rather than in batches. Demand for radiation-cured products is increasing at more than 10% a year in the USA, and will reach some 90 000 tonnes by the year 2 0 0 3 . Prices will remain at well above the levels of conventionally cured alternatives, such as coatings, inks, and adhesives, so that the total value of the market will increase at nearly the same rate, to US$1.3 billion. Freedonia concludes that coatings will remain the largest segment, at 5 1 % of total volume, with the advantages of coating onto heat-sensitive materials, overall better finished product quality and near-instantaneous cure. Flooring and furniture will be the main uses, with packaging, printing, and electrical and electronics providing other large markets.


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Table 12.8 Use of radiation-cured products in the USA, 1 9 8 9 - 2 0 0 3 (tonnes)

Coatings Inks Adhesives Other products Total demand Value of production (US$ million) Source: Freedonia

1989

1998

2003

% change (1989- -1998)

% change (1998-2003)

9980 6805 455 1360 18 600 275

28 575 19 050 1815 5900 55 340 800

46 270 30 390 2720 11 340 90 720 1270

12.4 12.1 14.8 19.8 13.0 12.6

10.1 9.8 10.3 13.4 10.4 9.7


CHAPTER 13 Modifying Processing Characteristics: Couplings Compatibilizing Agents Coupling agents may have a significant influence on mechanical properties, including impact strength, by acting as molecular 'bridges' chemically formed at the interface between two substrates, such as an inorganic fibre or filler and an organic polymer matrix, to improve the bond between the two. The Coupling Agent Index (Intertech) identifies six main types: • • • • • •

Organosilanes Organozircoaluminates Chartwell adhesion promoters Functionalized organic polymers Organotitanates Organozirconates

Organosilanes have long been used to improve the chemical bond between a variety of thermosetting resins and glass fibre and other silaceous surfaces, but they are essentially non-functional with organic-based fibres, such as graphite or aramid. Organometallic coupling agents, based on titanium or zirconium, offer a wider compatibility, in glass fibre-reinforced composites with epoxy and polyester and in aramid- and carbon-reinforced composites with epoxy, polyurethane, and vinyl ester. Significant improvements in wetting out and bonding and in the chemical resistance of thermosetting systems have been gained by, respectively, use of 0.2% aromatic aminozirconate with epoxy resin and an aromatic aminotitanate with a vinyl ester, using silane-sized glass in both cases. Improved process rheology has also been shown in thermoplastic matrices such as reinforced polyphenylene sulphide and polycarbonate. In thermoplastics, the organometallics appear mainly to provide a catalytic support bed for in situ re-polymerization of the polymer matrix, which reflects itself in improved processing. A test on a 40% polycarbonate/glass compound showed improvements in mechanical properties, together with significant improvements in productivity. Titanium-derived coupling agents are unique in that, by reacting with free protons at the inorganic interface, organic monomolecular layers are formed on

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the inorganic surface. Titanate-treated inorganics tend to be hydrophobic, organophilic, and organo-functional. When incorporated into polymer systems they can improve impact strength, promote adhesion, catalyse, and improve dispersion and rheology. They do not create embrittlement but can improve mechanical properties and make inorganic loadings of about 50% desirable, preventing phase separation and inhibiting corrosion. The use of organotitanate and/or organozirconate coupling agents, either independently or optionally together with other surface-reactive materials, such as organosilanes, also significantly improves the properties and processability of fibre-reinforced polymers, and their resistance to chemical attack and corrosion. Zirconate coupling agents provide a functional equivalent alternative to the silanes and titanates, correcting some of their disadvantages. They do not interact with hindered amines (HALS, used as light stabilizers and/or antioxidants) and, in unfilled plastics, they often improve ultraviolet stability, compared with titanates. Recent manufacturing improvement has reduced the original high cost. Table 13.1 At a glance: coupling, compatibilizing agents Function

To form chemical linkages between molecules that are normally incompatible

Properties affected

Mechanical strength, processability


Organosilanes, adhesion promoters, functionalized organic polymers, organotitanates, zirconates

Disadvantages

Complex chemistry, only partly understood

New developments

Could be significant in creating new polymer systems and making useful polymers from recovered waste


Two additions to its range of polymer modifiers have been introduced by Uniroyal Chemical, in its Polybond chemically modified polyolefins and Royaltuf modified ethylene/propylene terpolymer (EPDM) elastomers. Polybond 3109 is for polyolefins to improve the bonding between the non-polar resins and fillers and reinforcements such as glass, wood flour, and non-halogenated flame retardants. Produced from linear low-density polyethylene, functionalized with 1% grafted maleic anhydride, it has a melt flow index of 30 (six times higher than Polybond 3009), giving easier mixing and better performance. Royaltuf 498 is designed for nylon 6 resins, giving better impact resistance at low temperature. It is produced from EPDM, functionalized with 1% maleic, and has a Mooney viscosity of 30. Applications include housings for hand-held power tools and sporting goods.

CHAPTER 14 Modifying Processing Characteristics: Plasticizers

Table 14.1 At a glance: plasticizers Function

Added to make a compound more flexible, easier to process; mainly used with PVC; also for cellulosics.

Properties affected

Flexibility, viscosity.

Materials

Monomeric: esters of phthalates, adipates, benzoates, mellitates. Polymerizable esters: di-phthalate ester.

Disadvantages

Migration; strict compliance with food contact regulations.

New developments

Greater efficiency at lower addition levels, easier mixing; replacement of potentially hazardous types; reduction of leaching/migration.

14.1 The Function of Plasticizers

Many thermoplastics require an additive to plasticize them, either to render the basic material processable, or to extend the range of properties, either to render it repeatedly flexible, or to improve flexiblity at low temperature (sub-zero and well below). Plasticizers are low molecular or oligometric additives that are compatible with rigid thermoplastic polymers, rendering them semi-rigid or leathery/rubbery in behaviour. They can be either non-polymeric materials or polymer impact modifiers. Some forms of copolymerization can also produce a degree of internal plasticizing. Certain plasticizers can also perform other functions, assisting in viscosity control, in the dispersion of particulate additives such as fillers and pigments, and general lubrication of the compound (including mould release). Plasticizers are used mainly (about 80%) in PVC compounds, both flexible and rigid, which is unprocessable without a plasticizer. Over the years, certain of them have been withdrawn on the grounds of potential toxicity. Recently, phthalates have come under intense pressure due to fears of carcinogenicity and oestrogen interference.

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14.2 Main Types of Plasticizers The main types of plasticizers are summarized below. Table 14.2 Main types of plasticizers Phthalic acid esters Diethylhexyl phthalate (usually called dioctyl phthalate - DOP)

Most widely used: good gelling, relatively non-volatile under heat, satisfactory electrical properties and highly elastic compounds with reasonable cold strength

Diisotridecyl phthalate (DITDP)

Long-term heat resistance up to 105°C

Phthalates of straight-chain CyHn alcohols

Good non-volatile behaviour and good low-temperature properties

Esters ofadipic and sebacic acid Diisodecyl adipate (DIDA)

Less volatile than dioctyl ester (DOA, DOS)

Citric acid esters

Physiologically harmless: used in food industry

Polyglycol fatty acid esters

Good low-temperature resistance (to -30°C) and long-term heat resistance (100°C): addition of 0.05% bisphenol A prevents splitting of oxoalcohol ester plasticizers under heat stress

Tricresyl phosphate (TCP, TCP)

Outstanding heat resistance, good electrical properties, weather resistance, flameproof; not resistant to low temperatures; should not be used for products in contact with the skin. Other phosphates have lower resistance to heat

Parafflnic sulphonic acid phenyl ester

Midway between DOP and TCP in plasticizing properties: widely used in Germany

Oligomeric/polymeric plasticizers

Suitable for pastes (oligomeric) and extrusion/calendering compounds (polymeric); non-migratory, scarcely volatile, low dependency on temperature; some types resist extraction by aliphatic hydrocarbons, mineral oils or fats; some difficult to incorporate/compatible with PVC only in

PVC/EVA graft polymer

Soft films without plasticizer

Epoxidized soyabean oil, epoxidized esters

Combine functions of plasticizing and stabilizing

Source: Manufacturers' literature and International Plastics Handbook

14.2.1

Phthalates

Phthalates (phthalic acid esters) are among the most widely studied and best understood of all compounds. They are very efficient and are among the most important, and are certainly the most controversial, on grounds of alleged health hazard. This particularly concerns phthalates used in critical applications

Modifying Processing Characteristics: Plasticizers

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such as infant care and teething products, which are likely to be placed in the mouths of babies. They combine superior performance and cost effectiveness to create vinyl medical products that have led to improved and affordable patient care. Like many other chemicals, both synthetic and natural, phthalate plasticizers may be absorbed in small quantities by the fluids with which they come into contact, but this is a known occurrence and the safety of products is regularly reviewed and stringently monitored by both industry and regulatory authorities. The industry argues, however, that it has some 30 years of experience in using phthalates for another critical application, medical products. Phthalates account for 92% of all plasticizers and European production is running at about a million tonnes a year and growing at 3.7% a year. The breakdown of use of different types is: diethyl hexyl phthalate (DEHP), 51%; diisodecyl phthalate (DIDP), 2 1 % ; diisononyl phthalate (DINP), 11%; and others, 17%. As can be seen, the most widely used phthalate by far is di-2-ethylhexyl phthalate (DEHP), sometimes known as di-octyl phthalate (DOP). It gives good gelling, is relatively non-volatile under heat, and offers satisfactory electrical properties and highly elastic compounds with reasonable cold strength. It is also the preferred phthalate for medical devices because of its properties, which include maintaining flexibility at low temperatures combined with a resistance to high-temperature sterilization. Due to DEHP's unique properties, many different PVC formulations can be developed, ranging from glassy compositions to soft, highly flexible materials. It also enables the construction of transparent PVC products, a factor important in many medical applications. Its advantages in medical tubing include a high resistance to kinking to ensure that critical fluids reach a patient in prescribed doses. Phthalic acid esters of high-molecular-weight alcohols are used as special plasticizers for PVC, in liquid or semi-solid form. Diisotridecyl phthalate (DITDP) in liquid form is used for heat-resistant cables, offering long-term heat resistance up to 105°C. Dimethylcyclohexyl phthalate (liquid) is a special plasticizer for underbody automobile coating. Phthalates of straight-chain C7H11 alcohols offer good non-volatile behaviour and good low-temperature properties. 74.2.2 Sebacates and adipates

These materials provide good low-temperature plasticizers for PVC, in liquid form, with fairly general food-contact approval. Dibutyl sebacate is a highly efficient primary plasticizer for low-temperature applications, and is used in films and containers for packaging. 74.2.3 Fatty acid esters

Esters of fatty acids and monocarboxylic acids can be used as viscosity depressants for PVC pastes and also as secondary plasticizers for plasticized PVC compounds. They are in liquid form. Advice should be sought on food-contact

172


approval. Stearic acid esters are used as plasticizers and processing agents for various plastics and also as lubricants for polystyrene. They are semi-solid and have general food-contact approval. 74.2.4 Oligomeric/polymeric

plasticizers

Oligomeric and polymeric plasticizers (usually polyesters, based on adipic acid) extend the life of PVC end-products considerably. They reduce migration, extraction, and volatility. They are suitable for pastes (oligomeric) and extrusion/calendering compounds (polymeric). They are non-migratory, scarcely volatile, and have low dependency on temperature. Some types resist extraction by aliphatic hydrocarbons, mineral oils, or fats; some are difficult to incorporate or are compatible with PVC only in mixes. The molecular weight has a significant influence on performance but other factors also determine characteristics and performance. Typical applications include coated fabrics, protective clothing, electrical tapes, conveyor belting, food wrapping, laminated films, adhesive-coated films, heat-resistant cables, oil-resistant cables, oil and petrol hose, refrigerator gaskets, and roofing membranes. In PVC, monomeric plasticizers offer generally good low-temperature performance. They can be derived from a number of sources, such as phthalic anhydride, trimellite anhydride, benzoic acid, or adipic acid with monofunctional alcohols. They are oily limpid liquids with boiling points (at 760 mm Hg) higher than 300°C. They are highly compatible with PVC, with good gelling power and relatively low volatility. They can easily be incorporated into products giving high plasticity, low-temperature resistance, and glossy surface. Phthalic plasticizers are mainly used for standard applications with PVC. Trimellitates may be considered as special plasticizers, as they show less volatility and lower migration. Trimellitic acid ester (in liquid form) is a highly heat-resistant plasticizer, pre-stabilized for cable applications. Adipates are generally used in mixtures with other plasticizers, to increase plasticization and improve low-temperature properties. Benzoates are high solvating speciality plasticizers, used either alone or as primary components, but with interest now centred on development of new blends with specific characteristics. Monomeric plasticizers are also used to plasticize cellulose acetate. Some polymerizable esters can be used as a copolymerizable internal plasticizer in technical applications. The best known of the group is diallyl phthalate (DAP), which is used to replace styrene, divinyl benzene, or methyl methacrylate in unsaturated polyester resins. It has a very low vapour pressure (300°C boiling point), leading to significant reduction in loss through evaporation. It considerably improves properties such as hardness, chemical resistance, hydrolysis resistance, electrical properties, and product Ufe. It is particularly used in electrical applications, can be employed (after suitable preparation) in cold-cure systems, and shows high affinity to glass fibre. DAP can also be used as a reactive plasticizer with PVC resins.


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74.2.5 Epoxies

Epoxy plasticizers are used as stabilizing plasticizers offering properties of migration resistance in PVC compounds, alkyd resins, and chlorinated paraffins, and as pigment dispersing agents in plasticized PVC. They are recommended especially for food-contact and medical applications, giving low dosage levels, low odour, and good resistance to extrusion with good colour control. Specific grades are also good low-temperature plasticizers and effective co-stabilizers. Alkyl epoxy stearate plasticizers are used as low-viscosity stabilizers, especially in PVC pastes, with some grades providing good low-temperature properties. They are in liquid form. Soya bean versions have widespread approval for food contact. Advice should be sought for other types.

14.3 Extenders and Secondary Plasticizers

Extenders or secondary plasticizers are relatively cheap materials that gel with PVC without themselves providing adequate plasticizing. Some fatty acid esters and hydrocarbon products can improve the flow properties of pastes. Chlorinated paraffins are flame retardant. Monomeric glycol methacrylate reduces viscosity of pastes, but polymerizes in the presence of an added catalyst on gelation to the end product, and increases its hardness.

14.4 Health and Safety of Plasticizers

Concern about the effect of certain plasticizers on human health, particularly the carcinogenic and oestrogenic effects, has been expressed from some quarters and there has been extensive study and testing to establish the facts. The products particularly under scrutiny have been PVC compounds for medical products and baby- and infant-care products, especially those designed to be put in the mouth. DEHP, which is particularly suitable for medical products, has been most under examination. DEHP has for several years been recognized as non-carcinogenic (or unlikely to be carcinogenic) by most international authorities, including the World Health Organization, the European Commission, and Health Canada. Until now, however, the world's leading authority, the International Agency for Research on Cancer (lARC) classified it as 'possibly carcinogenic to humans', based on early studies on rodents. The lARC has concluded that more extensive recent research has shown that effects observed in rats and mice are not relevant to humans and the plasticizer is 'not classifiable as to carcinogenicity to humans'. There is a safety margin of about 14 000 in the estimated current intake of DEHP plasticizer, according to studies (by BASF). The plasticizer is considered detrimental to human reproductive organs after oral administration, at a level of 69 mg kg~^ body weight day~^. Several studies have indicated an average daily

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lifetime exposure of 2.3-2.8 jig kg~^ day~^ in Europe and 4 jig kg~^ day~^ in the USA. Research has recently turned towards oestrogenic effects, and has proved a controversial subject. Work suggests that the most commonly used phthalates do not produce any effect on human reproductive organs. A European Commission decision in 1990 confirmed that DEHP should not be classified or labelled as a carcinogenic or an irritant substance. Another study examined the possible health risk to humans from DEHP, particularly via its use in medical equipment, and concluded that a cancer risk is unlikely, even in haemodialysis patients, who are most exposed to the chemical. One of the world's leading manufacturers of medical devices, Baxter (which had been widely reported to be abandoning the use of PVC), estimates that acute and chronic exposure to DEHPplasticized medical products totals 5-7 billion and 1-2 billion patient days, respectively. DEHP is currently the plasticizer recommended in the European Pharmacopoeia for medical devices, and PVC containers are the only type listed for use for blood, blood components, and for aqueous solutions for intravenous infusion. Other materials can only be used subject to approval in each case by the national authority responsible for licensing them. An EU risk assessment, published at the end of 2000, concluded that no environmental classification was necessary for DINP (diisononyl phthalate) and DIDP (diisodecyl phthalate). This means that there are no product labelling requirements to indicate an environmental hazard. More significant is the finding that no further information or risk reduction measures are needed beyond those already applied. The conclusion is valid throughout the EU and represents an internationally accepted view.

14.5 Reducing the Level of Plasticizers

Although there needs to be constant vigilance regarding the intrinsic health and safety of plasticizers, leading to constant research to improve formulations, there has also been parallel work on the reduction in the use of these materials. Plasticizers enter the environment mainly by evaporation during processing of the plastics compound - estimated to range from 0.03% in injection moulding to up to 2% in coating processes. These levels are continually being reduced by installation of incineration, scrubbing, and filtration systems in processing plants. In PVC wall and floor covering, the use of plasticizer can result in small quantities of plasticizer vapour being present in room air: at 25°C, the maximum level of DOP which can be present in 1 m^ of air is approximately 0.01 mg and in recent emission chamber measurements, 1 m^ of PVC flooring tested for 96 hours showed no detectable level of plasticizer emission (at 4 parts per billion limit). Another line of recent development work has been to adjust the particle distribution of the resin system, to improve flow and use of plasticizer. Researchers at Hydro Polymers have confirmed that, in plastisols, it is possible to


17 S

reduce the consumption of plasticizers and diluents by using resin systems with perfectly spherical particles with an optimal particle size distribution. The level of plasticizer was reduced from 50 to 30 phr without changing the flow behaviour of the plastisol significantly. There was no sedimentation, and extremely thin films could be produced. An increased level of 15 jim monodisperse particle resin blended into a fine particle resin (0.2-2 |im) increased the amount of free plasticizer in the system.


Benzoate esters have been used as plasticizers in a number of PVC formulations for many years but, although they had been known to exhibit excellent stain resistance, UV resistance, and gelation properties (much valued, for example, in the PVC resilient flooring sector), their use has to some extent been limited by relatively high viscosity. New blending technology developed by Velsicol Chemical promises to bring these plasticizers back to the fore, with enhanced processing and properties and also better environmental performance. In PVC compounds, they act as high solvators but, unlike benzoate esters of older technology, they are low in volatile organic compounds (VOCs). Compared with other plasticizers they are often more efficient (up to 20% more efficient than DINP, it is claimed) and it may be necessary to reformulate some plastisols. They are also claimed to have Very desirable' environmental, health, and safety profiles. A halogenated flame-retardant plasticizer is produced by Uniplex, containing bromine and chlorine. It improves low-temperature brittleness and provides lower smoke than conventional brominated phthalate diesters, for use primarily in wire and cable applications of flexible PVC, EPDM, and thermoplastic olefins.


World capacity for plasticizers stands at present at some 4.5 million tonnes, due to growth in the higher weight molecular plasticizers DINP and DIDP at the expense of the commodity plasticizers. An 8% a year increase in demand is expected in these materials, compared with a 5% a year increase in commodity types. The average global rate of increase across the industry is predicted at 3.5% a year, producing a world market of some 6 million tonnes in 2010, led by Asia, Eastern Europe, and Latin America. The industry faces heavy overcapacity, however, as Asia becomes selfsufficient and export potential from European producers becomes more limited. A radical restructuring is expected.


CHAPTER 15 Modifying Processing Characteristics: Blowing Agents Table 15.1 At a glance: blowing agents Function

Creating a cellular structure during processing, usually by formation of an inert gas at the processing temperature; used for foams and expanded materials, injection moulded structural foam.

Properties affected

Cellular structure, stiffness/rigidity, lightness in weight; reduced shrinkage (especially at thick sections); reduction in moulding pressure.


Physical blowing agents; low-boil hydrocarbons. Chemical blowing agents: fluorocarbons (for polyurethane and PS foams); sodium bicarbonate/citric acid or azo compounds, etc., for moulded structural foams.

Disadvantages

Structural foam blowing agents may produce 'swirl' effect on surface of mouldings, requiring treatment before painting.

New developments

Replacement of CFC blowing agents (in polyurethane and polystyrene foams).

15.1 The Function of Blowing Agents

Blowing agents are added to (mainly thermoplastic) compounds to produce foamed materials which have the advantages of lightness and thermal insulation, and may sometimes also offer better stiffness and rigidity. There is also growing interest in direct injection of an inert gas during the injection moulding sequence, to form a core in a solid moulding, pressing the melt against the mould surface, preventing visible shrinkage, and allowing thick or hollow sections to be moulded without the usual penalty of sink marks. An expanded material has a cellular structure which, depending on the material, can be produced by physically introducing bubbles (usually of air or an inert gas), or by producing them chemically by means of blowing agents which decompose during the process (usually by heat) to release a suitable gas. Chemical blowing agents are used to produce polyurethane foams and PU foam mouldings (with integral skins) and to injection mould structural foam versions

178


of thermoplastics. The cells may or may not be interconnected (which can additionally be a property of the additives, or of subsequent physical processing of the expanded material to rupture the cell walls). Polyurethane foam is by far the largest user of blowing agents and has traditionally used chlorofluorocarbons (CFCs). Due to fears that these may harm the ozone layer, according to the Montreal Protocol the use of CFC gases for production of both polyurethane foam and expanded polystyrene has been virtually phased out, and a number of alternatives have been developed. To improve control of the formation of the foam during the process, and to achieve a uniform cell structure, other additives (called nucleating agents) are often used. It is also possible to extrude some thermoplastics in an expanded form by means of direct gassing, together with nucleating agents. The main gases used as blowing agents are listed below. Table 1 S.2 Blowing gases for plastics^ Name/type Alkane group n-Butane Isobutane M-Pentane Isopentane CFC group Rll R12 R114

Formula C4Hi() QHio C5H12 CsHi2

Molecular weight

Boiling point (°C)

58.1 58.1 72.2 72.2

-0.5 -11.7 36.0 28.0

CFCI3 CF2CI2 CF2CI-CF2CI

137.4 120.9 170.9

23.8 -29.8 3.6

H'CFC/HFAgroup R22 R123 R134A R141B R142B

CHF2CI CHCI2-CF3 CH2F-CF3 CCI2F2-CH5 CCIF2-CH5

88.5 152.9 102.0 116.0 100.5

-40.8 27.8 -26.5 31.7 -9.8

Other gases Argon Carbon dioxide Nitrogen

Ar CO2 N2

39.9 44.0 28.0

-163.8 -78.4 -195.8

'*Abbreviations: CFC, chlorofluorocarbon; HFA, hydrofluoroalkane; H-CFC, hydrochlorofluorocarbon. Source: Boehringer Ingelheim

15.2 Physical Blowing Agents

These can be low-boiling organic solvents (preferably hydrocarbons) that cause foaming by their vapour pressure during the conditions of processing, or in the form of compressed gas or volatile liquids that undergo a phase change at elevated temperature. These include (with their boiling points): pentane and heptane (30-100°C), chlorinated hydrocarbons such as methyl chloride (24°C),

Modifying Processing Characteristics: Blowing Agents

179

methylene chloride (40°C), trichlorethylene (87°C), and chlorfluoralkane ( 4 0 50°C). For expanded polystyrene beads they are usually incorporated during polymerization, for expandable polystyrene beads, or introduced into an extruder, for extruded expanded PS sheet. In some processes, plasticized PVC in a compression mould or other types of thermoplastic in a special injection moulding machine are saturated with nitrogen under about 200 bar pressure, the gas expanding the mouldings on secondary heating, or in the injection mould. Compressed air or CO2 is mixed into PVC plastisols for foams, which are subsequently gelled, for backing floor covering or conveyor belting.

15.3 Chemical Blowing Agents (CBAs)

CBAs are solid organic compounds that release nitrogen gas at a specific processing temperature. They are finely distributed solids, decomposing under heat, to release a gas. They may range from simple salts such as ammonium or sodium bicarbonate to complex nitrogen-releasing agents. Most CBAs generate nitrogen. Sodium bicarbonate releases carbon dioxide, but the reaction also produces water, which can cause rust on steel moulds. The CBA group also includes the CFC replacements, such as hydrochlorofluorocarbons (HCFCs). Polyurethane foams have also been developed using carbon dioxide as the blowing agent. Examples of chemical blowing agents are azo compounds, N-nitrosocompounds, and sulphonyl hydrazides, which yield 1 0 0 - 3 0 0 cm^ of nitrogen per gram of compound at temperatures of 90-275°C. Azodicarbonamide is widely used, having a decomposition temperature of 230-235°C, which can be reduced to 155-200°C by means of metal compounds such as lead and zinc stabilizers. It can thus match the temperatures at which the melt viscosity of many polymers is suitable for foaming, and is used (typically) in calendered PVC and PVC plastisols and in structural foam forms of polyethylene, polypropylene, PVC, polystyrene, and ABS. Chemical blowing agents are added to the granular compound either in separate batch mixers or in a blending unit mounted on top of the injection moulding machine. With powder products it is recommended to add 0.1% adhesive to avoid subsequent separation. Liquid blowing agents can be added directly into the injection cylinder by a dosing pump, operating in parallel to the material feed. Chemical blowing agents can be classified as exothermal or endothermal, according to their energy requirements during decomposition. Exothermal blowing agents release more energy during decomposition than is needed for the reaction. Once started, decomposition continues spontaneously (and can continue after the energy supply has stopped). Parts blown this way must be cooled intensely, to avoid post-expansion. Typical agents are hydrazides and azo compounds. Due to possible skin irritation, precaution should be taken when handling these substances. Azo compounds are characterized by a yellow colour, which can lead to changes in colour of the mouldings produced.

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Endothermal blowing agents require energy for decomposition and gas release therefore stops quickly after the supply of heat is terminated. Shorter cooling periods are needed and moulding cycles are therefore shorter. The base materials are bicarbonate and citric acid - which are also used as food additives, and present no handling problems. Other blowing agents are under development for foaming engineering polymers and/or to overcome problems occurring, such as corrosion of screws, barrels, and moulds, and uneven cell structure.

15.4 Structural Foams

Thermoplastics can be foamed, giving useful structural properties while also saving in material weight and cost, with improved thermal and acoustic insulation. There are two basic technologies: direct gassing and the use of chemical blowing agents. Direct gassing is a process in which physical blowing agents (such as fluorocarbons, hydrocarbons, nitrogen, and carbon dioxide) are introduced into the thermoplastic melt during processing. Good distribution of the agent and thus a regular fine-cell structure are obtained by adding a nucleating agent. Chemical blowing agents decompose during processing to form gaseous decomposition products that produce a cellular material. They can be mixed directly with the plastics compound, in granular form. The main criteria are: good gas yield, regular cell structure, harmless decomposition products, and minimal influence on properties and colour of the finished product. Most blowing agents conform to international health and food regulations, and are classified as GRAS (Generally Recognized as Safe) under FDA regulations Table 15.3 Typical processing temperatures for thermoplastics Resin/application

LDPE/EVA LDPE (direct gassed injection) HDPE/PP TPE/TPU/TPR PS PS (direct gassed injection) ABS PPO/PPE/engineering resins Painted parts (PS/ABS/PPO) PET extrusion Co-injection of PP (foam core) Co-injection of PS, ABS (foam core) PC (reinforced) PVC boards, pipes, profiles Polyamide

Melt temperature °C

op

180-210 190-200 210-230 170-210 210-230 210-230 230-360 240-270 210-260 230-260 220-240 210-260 280-310 170-190 240-270

350-410 370-390 410-450 330-410 410-450 410-450 450-500 460-520 410-500 450-500 430-460 410-500 530-590 330-370 460-520


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and meeting German food regulations (Bundesgesundheitsamt C III-2 7063365/79). Chemical blowing agents can be processed on standard injection moulding machines. It is advantageous to use a shut-off nozzle to prevent the melt from premature foaming and 'drooling'. To achieve a uniform foam distribution together with a solid skin, the gas should expand in the melt after injection into the mould and injection speed should be as high as possible (possibly with the aid of a gas pressure accumulator). Dedicated foam-making machines have a separate plasticizing unit and transfer cylinder for faster injection. Blowing agents will, typically, comprise a range of grades which commence decomposition at 135-240°C, with recommended processing temperatures ranging from 170-215°C to 285-310°C. Typical processing temperatures for thermoplastics are shown in Table 15.3. 75.4.7 In-House gas generation

For larger users of nitrogen blowing agents, an in-house gas generation system has been developed by Air Products (under the name Prism HP). It separates 99.5% pure nitrogen gas from the air and stores it in a low-pressure storage buffer. From there, the gas is passed to a high-pressure compressor, which takes it up to 350 bar, and then to high-pressure buffer storage. It can then be delivered to the moulding machine(s) in the factory through a high-pressure distribution network, via localized control units with user-friendly graphic interfaces. 75.4.2 Nucleating

agents

Nucleating agents and regulators of pore size play an important part in physically and chemically blown thermoplastic foams, helping to produce a uniform cell structure. They are fine-particle solids or mixtures that release CO2 (such as sodium bicarbonate, with solid organic acids such as citric acid). 75.4.3 Dispersion

agents

These allow improved dispersion of fillers, especially useful when high loadings of alumina trihydrate are required for low smoke, halogen-free FR formulations. A small addition to the resin allows more filler to be added without increasing viscosity.

15.5 Syntactic Structural Foam

As an alternative to blowing agents, it is also possible to introduce lightweight void-forming pellets or 'prill', manufactured from ultrafine ceramic foam. These are strong, insulating, and flame resistant, with a density of 1 0 0 - 2 0 0 kg m"^. Grades (such as Tecpril, from Filtec) are stable to 1050°C and exhibit no

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dimensional change due to changes in humidity, from 0 to 100% at 20°C. They cannot generate smoke or hazardous gases at high temperatures and resist attack by most chemicals. A syntactic foam produced by mixing a polyurethane compound with millions of tiny gas-filled microspheres has been used for high-performance footballs. Developed by the sports company Adidas and Bayer, the foam makes up the top one-third of the outer skin of the footballs. When a football is kicked, the microspheres restore its shape very quickly, producing a very high elastic recovery compared with other football constructions, with the effect that the ball deviates very little from its initial flight path.

15.6 Replacement of CFCs

CFCs have long been the most effective blowing agents for polyurethane foams, and many processes, such as rigid foam and integral skin moulding, have virtually been built around them. But, due to concern about the possible effect of chlorine-containing chemicals on the stability of the Earth's ozone layer, it was decided internationally through the Montreal Protocol to reduce the use and manufacture of CFCs and replace them with other chemicals. For polyurethanes this has been achieved with the introduction of other chemical systems, including water-based systems that generate CO2. There is no direct alternative blowing agent for polyurethane foams that combines the advantageous properties of CFCs and the trend has been to develop replacements specific to individual applications. Much has been achieved but the present blowing systems are widely regarded as interim solutions: in the longer term, the solution is seen in pentane-based compounds. The main CFC to be replaced is CFC R l l (trichlorofluoromethane), which offers high molecular weight and therefore low thermal conductivity, low boiling point and therefore good blowing action, high chemical stability, non-toxicity, non-flammability, and low price. The first potential substitutes were partially halogenated CFCs (HCFCs). These have significantly lower ozone depletion potential (ODP) than R l l , but it is still not zero. They are regarded therefore as only an interim solution and a complex withdrawal programme for HCFCs was agreed at the follow-up conference to Montreal, in Copenhagen in 1992 -essentially a stepwise reduction from 1996, reaching total removal by 2030. Additional national legislation has been enacted in some countries, concerned that this timescale was too long (current US environmental regulations call for complete phase-out of production and importation of HCFC by 1 January 2003). Future conferences may shorten the period. In addition to ozone depletion, the 'greenhouse effect' is important. Greenhouse warming potential (GWP) of a compound depends primarily on its reactivity towards hydroxyl free radicals, which in turn determines their concentration in the stratosphere. A second factor is their absorption capacity for infra-red radiation, primarily determined by bonds between carbon and


183

fluorine. This is an argument against HCFCs and also against another possible CFC substitute, HFCs. Some companies have therefore concentrated on completely halogen-free alternatives, but it is evident that there is no universal replacement, and the subject is better dealt with on a material-by-material basis, as discussed in the following. 75.6.7 Flexible foams

Carbon dioxide formed through reaction of isocyanate groups during polymerization can serve directly as the blowing agent. The urea groups also formed are a problem, causing hardening of the PUR matrix, and new polyols have been developed to counter this effect. CFC R l 1 has therefore been replaced in virtually all types of flexible PUR foam. Foaming of PUR in a closed metal mould produces a temperature gradient in the foam in which the areas in contact with the good thermally conductive mould are cooler than the centre. If the blowing agent is selected so that it has a higher bofling point than the temperature in these areas, the resulting moulded product will exhibit a low-density foamed core surrounded by virtually unfoamed dense skins, making a useful structural foam component. The boiling point of the replacement agent is therefore critical. Flexible structural foams (as for shoe soles, steering wheels, and armrests) need a soft elastic core and a suitable R l 1 replacement is n-pentane, which has a boiling point of 3 6°C, only slightly higher than that of R11, with similar foaming properties. Flammability was a problem, but this has now been solved and many users have now switched to n-pentane. A non-flammable alternative is water adsorbed onto solid support material such as zeolite, silica gel, or activated charcoal, no longer reacting spontaneously with the isocyanate groups, but at an elevated temperature, desorbed from the support and able to react. Choice and modification of the support allows the temperature profile of the foam to be converted to a corresponding density profile by the amount of water liberated, and the process is now used successfully for production of automobile components. Rigid structural foams release more heat during the reaction and a blowing agent with a higher boiling point is needed - but this could cause severe foaming problems. A completely different solution has therefore been adopted, using tertiary butanol that reacts with isocyanate to form isobutene, carbon dioxide, and amine (which reacts with isocyanate to form urea). The first reaction is highly temperature dependent and therefore fits well with the desired temperature profile for formation of rigid structural foams, and has been largely adopted by producers. 75.6.2 Rigid foams

Replacement of CFCs in rigid polyurethane foams has been a much more serious problem, since the main use of these foams is as heat insulators and the main property required is therefore low thermal conductivity. Blowing gases of high

184


molecular weight would be advantageous, but the boiling point of inert organic compounds also increases with molecular weight rendering them less suitable as blowing agents. Apart from halogen compounds, it is thought that there is no organic substance known that simultaneously meets all of the criteria of the user: a boiling point lower than 50°C and thermal conductivity less than 10 mW mK~ ^. Non-polar compounds such as hydrocarbons come closest to CFCs and HCFCs and cyclopentane is nearest to the ideal (though not perfect). After optimization and adaptation to cyclopentane, foam formulations are now giving insulation values for refrigerators virtually identical to those of R 11 with similar diffusion results. The European refrigerator industry has converted to cyclopentane, and the changeover is also starting in other sectors. Safety concepts for cyclopentane are essentially based on experience with n-pentane. The French public health administration (Counseil superieur d'hygiene publique de France) has expressed a favourable opinion on the use of Forane 141b as a blowing agent for rigid polyurethane foams for refrigerators and freezers. This was the first product to be granted this official approval and was the conclusion of more than five years of studies carried out by Elf Atochem with different partners to check that, within the framework of the present regulations, Forane 141b can fully meet users' requirements. The studies have demonstrated that this non-flammable product has toxicological characteristics that allow its use in existing industrial facilities and, in particular, in refrigerator wall panels. It has physical properties leading to a thermal insulation efficiency that is higher than other industrial processes. A non-ozone-depleting chemical blowing agent developed by AUiedSignal is HFC-245fa (hydrofluorocarbon), for use in rigid polyurethane and polyisocyanurate foam insulation applications, including refrigerator and freezer insulation foam, and also in boardstock for roofing and sheathing and spray foam for construction. The new agent is non-flammable and is not considered to be a volatile organic compound. The insulation performance matches that of HCFC-141b and is superior to other non-ozone-depleting products, such as hydrocarbons and HFC-134a, claims AUiedSignal. For the USA, the EPA has scheduled HCFC-141b for phase-out on 1 January 2003. Honeywell's new HCFC replacement, HFC-245fa, has received approval from the EPA. It is intended as a replacement for HCFC-141b in a range of rigid polyurethane and polyisocyanurate foam insulation applications, including foam for insulation of refrigerators and freezers, boardstock foam for construction of roofing and sheathing, and spray foam, also for construction. The new blowing agent is non-flammable and is not considered a volatile organic compound, offering worldwide a safe alternative to use of hydrocarbons. It also offers an insulation performance matching the HCFC it replaces and superior to other non-ozone-depleting products, such as hydrocarbons and HFC-134a. 75.6.3 Pentane

It is expected that the trend towards use of carbon dioxide will continue but, where it is not possible to achieve the necessary properties, flammable organic


185

compounds will be used. Expensive, partially fluorinated HFCs with their relatively high GWP will only be used where non-flammability is essential. Chlorine-containing compounds, however, must be replaced completely. Pentane presents itself as a possible solution to finding an efficient blowing agent which also meets environmental regulations, and years of experience in using it have shown that processing can be safe, as long as safety devices are fully implemented. Bayer's PU machinery subsidiary, Hennecke GmbH, has developed a state-of-the-art system that monitors all critical control points along the processing chain, to ensure safe production. Among the features are: • • • • •

completely encapsulated machinery and units (including in-line blenders, work tank, and high-pressure reaction casting machine), also aerated and fitted with exhaust devices, pentane gas sensors, and other safety devices; a metering and blending supervisory system (Pentament), also permanently vented to prevent gas build up; an electronic security system controlling all safety features, which can shut down operations, if necessary; pentane gas warning sensors monitoring all critical components; and an independent decentralized control system, alerted to all trouble indicators from primary and secondary sensors and monitors.

The modifications were designed to add safety checks to all critical points, first pinpointing all potential hazards (such as ignition sources, leakage points, and static charging) and then developing integrated safeguards. Bayer and Apache Products have discovered that, by extrusion mixing of high levels of fillers and/or diluents in a PU formulation, loadings of 10-50% filler by weight can be achieved while maintaining or improving key physical properties. The technology makes it possible to handle high-viscosity dispersions effectively, which may reduce production costs of rigid boardstock. Use of solid fillers, solid combustion modifiers, and hollow fillers was studied, suggesting that the higher cost of hollow fillers can be offset by density reduction in the foam board and increase in compressive strength. Use of this more environmentally friendly alternative may be facilitated for manufacturers of domestic appliances following the introduction of new safety features in the CycloFlex and LinFlex systems for refrigerator cabinet production. Hennecke Machinery has developed a comprehensive safety system for pentanebased foam production, meeting many of the reservations of US manufacturers of PU board. 75.6.4 Expanded

polystyrene

The blowing agent for expanded polystyrene in the past was dichlorodifluoromethane (R 12), with a co-blowing agent. The progressive replacement is shown in the table below, leading to carbon dioxide and replacement of the co-blowing agents methyl chloride and ethyl chloride by ethanol for toxicological reasons.

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Table 1 ?.4 Replacement of blowing gases for expanded polystyrene Period

Blowing gas composition

Comment

Until 1985 1985-1988 From 1988 From 1990 From 1992 From 1994

R 1 2 + methyl chloride R 1 2 + ethyl chloride R 12 + ethyl chloride + carbon dioxide R 142b + ethyl chloride + carbon dioxide R 142b + ethanol + carbon dioxide Carbon dioxide

Methyl chloride in Class 111 b^ R 12 reduction HCFC instead of CFC Ethyl chloride in Class 111b'' HCFC elimination

^ German hazardous substances regulations. Source: BASF

75.6.5 Economics of CFC

replacement

The investment required for switching to an HFC-245fa PU system may be less than originally believed, according to a study of appliance manufacturer Whirlpool. A major concern of the appliance industry has been the relatively low boiling point of the blowing agent (at 15°C), but the research shows that this does not demand processing at temperatures lower than those generally in use in the appliance industry today. Additionally, the processing window for HFC-245fa foams does not appear to be radically more limited than HCFC-14lb systems. Existing foam equipment should be capable of processing good-quality foam blown with the new agent, concluded Bayer and Whirlpool. 75.6.6 Festing the insulation value of blowing

agents

A method of testing the conductivity of various blowing agents in the vapour phase, providing a means of predicting the insulation value of the resulting foam, has been developed by Bayer. The insulating properties of the foam are primarily determined by the blowing agent. Essentially an experimental procedure based on the transient hot wire method, with apparatus developed in cooperation with the University of Stuttgart, Germany, it has been tested for vapour-phase thermal conductivity of 10 blowing agents, of which CFC-11 showed the lowest level. Of the alternatives, cyclopentane showed the next best results, especially at low temperatures (which is a key point for refrigeration). The method is claimed to give accurate results and provide absolute values. No calibration is required (as, for example, when a gas chromatograph is used) and the method and resulting data are useful in modelling and predicting the insulation value of the foam produced with the blowing agent.


Endex ABS 50 is a new endothermic foaming agent for a wide range of thermoplastics, including polycarbonate, polyphenylene ether, nylon.


187

polyethylene, polypropylene, and PET. A 50% active pelletized concentrate, it generates fine closed-cell foams leading to high-quality mouldings and extrusions. Faster cycle times and extrusion rates are combined with elimination of sink marks, functioning as an effective nucleating agent for direct-gassed products. Environmental Products' EPIcor 972 is a 70% active endothermic foaming agent concentrated in a universal carrier resin, claimed to have the highest gas yield of any on the market. EPIcell 700 is an exothermic chemical foaming agent for cellular plastics and rubber, for use with PE, PVC, EVA, and TPO. For structural foam in PC and PC/ABS, POLYcor 263 is an endothermic/endothermic mixture in a polystyrene carrier, and POLYcor 288 a combination of an acid/ carbonate and 5-phenyl tetrazole in one pellet. The former gives a finer structure, reducing cycle time with excellent surface properties and fast gassing. Quantum has introduced Spectratech chemical blowing agent concentrates giving high gas yields at low processing temperatures: FM 2169H is endothermic, compatible with PS; FM 2171H is endothermic, compatible with styrenics; and FM 2182H is compatible with polyolefins. A blend of hydrocerol and azodicarbonamide blowing agents is offered by Bl Chemicals, for PVC, thermoplastic elastomers, and other low-temperature processing thermoplastics, in appUcations requiring high gas yield and weight reduction. It is in the form of a yellowish free-flowing powder, reported to have good storage stability. Decomposition begins at 120-140°C and working temperatures of 120-170°C or higher are recommended. 75.7.7 Liquid carbon

dioxide

New technology allowing the use of liquid carbon dioxide as a blowing agent for flexible polyurethane foam products has been developed by Gusmer-Admiral, Ohio, USA. It is being used commercially by Japanese manufacturers who are reported to have found it both reliable and affordable. The process is claimed to offer a solution to the challenges presented to the industry by the mandated phase-out of commonly used blowing agents such as methylene chloride. Rather than pre-blending the blowing agent with a polyol before injection into the foam mixing chamber, the process uniquely introduces a stream of liquid carbon dioxide directly into the mixing head. This allows the moulder to stop and start injections of short duration, without altering the concentration of carbon dioxide in the reacting mixture, and without the need to re-circulate the gas back to the day tank of the machine. It uses a double-acting piston pumping system, providing precise control of the liquid carbon dioxide. The system allows re-circulation at pressures of up to 3000 psig, and the control system provides for very tight control of temperature of the re-circulating liquid, with built-in capacity to account for changes in carbon dioxide density with respect to temperature. The mixing head also allows either of two polyols to be selected for reaction with the isocyanate, and the moulder has the choice of pouring with or without carbon dioxide, on an intermittent basis, allowing better control over dispersion, solubility, andpre-expansion.


CHAPTER 16 Modifying Processing Characteristics: Modifiers and Processing Aids Table 16.1 At a glance: process modifiers and processing aids Function

Improvement of processability of compounds: lubrication, higher output/lower energy; modification of polymer properties: nucleation for greater product homogeneity; clarifying agents for improved transparency

Properties affected

Productivity; product quality, transparency


Fluoropolymers; sorbitol clarifying agents; elastomeric property modifiers, polybutene, acrylic; silicone modifiers; MBS, acrylic impact modifiers; fatty acid dispersion aids

Disadvantages

No significant disadvantages known

New developments

Improvement in productivity, energy requirement for processing

16.1 Impact Modification

The improvement of physical properties, particularly impact strength, is the role of an important group of additives, both for thermoplastics and thermosets. The aim is to compensate for inherent brittleness, or embrittlement occurring at subzero temperatures, notch sensitivity, and crack propagation. The mechanism is normally to introduce a component that can absorb the energy of an impact, or dissipate it. One of the main methods is to introduce microscopic particles of rubber, but there is also considerable interest in the surface treatment of fillers and other additives, such as pigments, to give them an impact modification function also and so add to their value. An key requirement of an impact modifier is its ability to bond, either mechanically or, more recently, chemically, with the matrix polymer. It is important, however, to differentiate between impact modification and reinforcement. In some polymer matrices, reinforcement such as glass fibre actually makes the matrix more brittle (and an impact modifier has to be included).

190

Additi ves fo r Plus tics Ha ndbook

Early development concentrated on the improvement of standard plastics, such as the thermosets, phenolic and polyester resins, and the thermoplastics, polystyrene, PVC, and polyolefins. More recently there has been considerable development of impact modification systems for engineering thermoplastics. 76.7.7 Impact modifiers for PVC

Impact modifiers for PVC include methyl butadiene styrene (MBS) and acrylics. MBS modifiers improve the impact strength of PVC compounds without sacrificing the other characteristics. They are used for a variety of rigid and semirigid appUcations and processes, such as blow moulding of bottles, calendering of film and sheet, extrusion of profiles, and injection moulding of technical parts. Some types can also be tailored to suit specific requirements. Acrylic modifiers also significantly improve impact characteristics, but offer particularly good weather resistance. The main applications are profiles, pipes and sheets. Co-monomers are used in the reactor, but additive forms are gaining in popularity. 16.1.1.1 MBS modifiers MBS impact modifiers are used for PVC (transparent and low temperature applications, mainly in packaging), and for engineering thermoplastics, especially for low temperature applications (PC, PBT and blends). Rohm and Haas' Paraloid range covers a very wide range of applications. For example, KM 3 55 gives low die swell, resulting in low post-extrusion shrinkage (reversion), improving throughput rates. In free-flowing powder form, it can be handled in automatic weighing and conveying systems. A new grade is Paraloid HIA 80, giving high impact performance with good clarity and weather resistance, for use in outdoor applications. Paraloid KM 377 is an impact modifier for construction products, with improved impact and weather resistance and good gloss-holding properties and BTA 730 and 751 are MBS modifiers, respectively, for clear sheet and film and opaque non-weatherable applications. Paraloid BTA 780-S is a methyl methacrylate butadiene styrene (MBS) for PVC packaging applications, in particular for film and sheet, claiming a unique combination of impact, crease whitening resistance and clarity. 16.1.1.2 ABS modifiers Claimed to provide better optical properties than is normally available from MBS modifiers, with especially good haze and transparency, is an ABS-based high impact modifier for PVC, by GE Specialty Chemicals in its Blendex range. Blendex 415 also differs from conventional MBS modifiers by offering the superior chemical resistance and low crease-whitening performance associated with ABS. It will perform well in even the most demanding applications, giving good impact strength, melt strength and formability, at competitive cost. It is expected to find widespread use in extrusion applications, including manufacture of PVC bottles.

Modifying Processing Characteristics: Modifiers and Processing Aids

191

16.1.13 Acrylic modifiers Acrylic impact modifiers are used for rigid PVC (particularly for weatherable building applications) and for engineering thermoplastics (polyamides, PC, PBT, PET). Table 16.2 A quick guide to impact modifiers Type

Application

Some typical brand names

Styrenics

Mainly for styrenes and ABS; latest types also for polyolefins and engineering plastics; can also be used with SMC/BMC

KratonG-Shell

Olefinic

Mainly for PE and PP; also for PBTs; function as compatibilizers

Dutral - Ausimont Nordel IP - DuPont/Dow Royaltuf- Uniroyal Exxelor, Escor AT - Exxon

Polybutadiene

PS, ABS

Diene - FirestoneKrynac - Bayer Taktene-Bayer

Polybutenes

Use with ABS, also for PP/EP blends

Acrylic elastomer

Gives 'super-toughness' to nylon 6

Dimer acids

Modification of polyamides and polyesters

Calcium carbonate, talc

Engineered (surface-modified) grades improve polyolefins

Cimpact (talc) - Luzenac Hi-Flex - Specialty Minerals Hydrocarb - Omya PoleStar,ZytoCal-ECC Winnofil-ICI

Silicones

'Core-shell particles' developed for compatibility with organic polymers: low temperature flexibility

WackerChemie Albidur - Hanse Chemie

MBS

Widely used in PVC; can also be used with engineering plastics (PC, PBT and blends), especially for low-temperature impact modification

Paraloid - Rohm and Haas

ABS/nitrile

For PVC, claimed to give better optical properties

Baymod-Bayer Blendex - GE Specialty Chemicals

Acrylic

Weather-resistant impact modifiers for PVC

Durastrength, Metablen Elf Atochem Kane Ace - Kaneka Paraloid - Rohm and Haas

EVA/PVC graft

Improves impact resistance of PVC, light-fast, good weathering, can also reduce plasticizer migration

Levapren-Bayer VinnoUt - Wacker

Coupling agents

Improve compatibility, bond strength between polymer and reinforcement or filler

Epolene - Eastman Hostaprime - Clariant Ken-React, Ken-Stat-Kenrich

Europrene - EniChem

192


Kane Ace FM is an acrylic high weather-resistant impact modifier for PVC products such as window profiles, siding and business machine housings, based on Kaneka technology. It imparts good processability, gelation behaviour, heat stability and low die-swell in lead-stabilized compounds, at addition levels of 8phr. Elf Atochem's new generation Durastrength 300 is an acrylic modifier, for PVC profile and cladding. It offers improved rheology and low torque, optimizing mechanical properties together with processability, with higher screw speeds and improved output. Increases of 2 5-50% in output for the same impact strength have been demonstrated. Low-temperature properties are also superior. Also from Elf Atochem is Metablen S-2001, a silicone-modified acrylic impact modifier, for high impact strength and good weatherabilty in PVC. Rohm and Haas has added Paraloid KM 355 to its range, offering improved efficiency and cost-saving. It has low die swell resulting in low post-extrusion shrinkage (reversion), improving throughput rates. In free-flowing powder form, it can be handled in automatic weighing and conveying systems. A recent grade is Paraloid HIA 80, giving high impact performance with good clarity and weather resistance, for use in outdoor applications. Paraloid KM 377 is for extruded vinyl products for the construction industry, with improved impact and weather resistance and good gloss-holding properties. A graft polymer developed by Wacker (Vinnolit VK 802), based on ethylene vinyl acetate and polyvinyl chloride, improves the toughness of rigid, semi-rigid and flexible PVC mouldings. It can be used to product impact-resistant PVC films for pipe insulation, furniture films and credit card lamination, as well as selfadhesive films and labels. Available as a free-flowing white powder, it also features Ught-fastness and resistance to weathering and ageing and can also reduce plasticizer migration in flexible mouldings.

16.2 Elastomer Modification

Rubber has always been used as a component or additive to plastics. Essentially the rubber provides a network of 'buffers' in the plastic matrix, forming an energy-absorbing or dissipating phase, that will physically absorb or dissipate the energy of an impact, over a broad range of temperature (especially at the lower rather than the higher end of the scale). It is important, though, to choose a rubber with the right volume fraction, morphology and interaction with the plastic matrix is commonly obtained by in-situ reactor polymerization, grafting or melt blending. The classic technology is the modification of general purpose polystyrene with styrene butadiene to produce high impact PS. Butadiene has also long been used, especially in ABS. Polyisoprene is a more recent modifier. InitiaUy, modification could be achieved simply by compounding but, with improvement in technology, copolymers were developed and the function was taken upstream to the reactor. With the advent of polyolefins, a different system was needed, especially when, with the development of PP, it was clear that its useful mechanical properties fell

Modifying Processing Characteristics: Modifiers and Processing Aids

193

off rapidly at temperatures below 0°C. A compatible elastomer, EPDM was used again, first as a mechanical blend and subsequently as a reactor-made combination. 76.2.7 Acrylic

rubber

Acrylic elastomers have previously been used only in the rubber industry and conventional polymers (EEA or core-shell acrylate polymers) are based on the rubber in hard phases. Based on the soft phase only, however, EniChem's Europrene AR uses original technology for modification of PA 6 with conventional acrylic rubber in granule form. It increases the specific rubber efficiency in the impact resistance characteristics, so differing from other traditional elastomers (EPR, SEBS) used in modification of nylon. A 'super-toughness' level is obtained with only 17% Europrene AR and impact resistance characteristics are better than those obtained with 2 0 - 2 5 % of other elastomers. Both the low level of rubber and intrinsic characteristics of the softphase acrylic increase the resistance to high temperature (Vicat B = 170°C) and the flexural modulus of modified nylon. The high thermal/mechanical inertia and the polarity of these rubbers also allow post-treatments to the nylon that were not previously possible. 76.2.2 Styrenics

Styrenic block copolymers and their compounds have been in widespread commercial use for many years, with many applications. With the latest technology, they have become particularly interesting as impact modifiers for plastics, both thermoplastics and thermosets. Most polymers are thermodynamically incompatible with others polymers and mixtures tend to separate into two phases, even when they are part of the same molecule, as in block copolymers. Poly(styrene-P-elastomer-P-styrene) copolymers, in which the elastomer is the main constituent, give a structure in which the polystyrene end-segments form separate spherical regions ('domains') dispersed in a continuous phase. At room temperature, the polystyrene segments are hard and act as physical cross-links, tying the elastomer chain together in a three-dimensional network, not unlike the network that is formed by cross-linking of thermosetting rubber during vulcanization. Well-known materials are the Kraton polymer range, originally developed by Shell, and are produced in several types. The D series has an unsaturated rubber midblock - styrene/butadiene/styrene (SBS), and styrene/isoprene/styrene (SIS) - and the G series has a saturated midblock - styrene ethylene/butylene styrene (SEBS) and styrene ethylene/propylene (SEP). The G series has increased resistance to oxidation and weathering, higher service temperature and better processing stability. The development of a second generation (such as the Kraton G series) introduced selective hydrogenation technology, allowing conversion of

194


polybutadiene or polyisoprene into, respectively, polyethylene/butylene (S-ES-S) or polyethylene/propylene (S-EP-S) rubber. They can be compounded with other polymers, fillers, flame retardants, and other additives, often to as little as 25% of the S-EB-S polymer. They can be used in polymer modification of thermoplastics and SMC/BMC materials. Hydrogenated S-EB-S block-copolymers can be used with olefinic plastics such as PP and PE because of their higher temperature allowance, and even with engineering plastics that usually need melt temperatures well above 275°C. But for polar engineering plastics, such as PA 6 and 66, maleic anhydride functionalized polymers have been developed and commercialized. Systems available to improve impact resistance of high-performance plastics are given in the table below. Table 16.3 Kraton G as a compatibilizer Plastic

Kraton G-type

%

Impact (Izod, notched, 23°C)(kJm-^)

Without Kraton G

PA 6 PA 66 PET PBT PC Mod PPG

FG/G FG-1901 FG-1901 FG-1901 G-1651 G-1650

13/7 20 20 20 10 15

65 100 100 100 70 30

B

Single burning item in a room

Level of exposure: C radiation on a limited area of max. 1 0 kW m-l

D

Small fire attack Level of exposure: on a limited area burning cigarette of a product

Test methods

No contribution to fire

Very limited calorific content and heat release. No flaming combustion. Limited mass loss

Documents: CEN/TC 12 7/N 2 2 9 and CEN/TC 12 7/N 2 3 0 , and list of non-combustible products

Very limited contribution to fire

Very limited calorific Documents: content and/or heat release. CEN/TC 127/N 2 2 9 and Limited mass loss. CEN/TC 12 7/N 2 3 0 Physically no spread of flame. Very limited smoke production

Limited contribution Very limited spread offlame Documents: to fire and smoke production CEN/TC 12 7/N 1 2 5

Acceptable contribution to fire

E

Acceptable reaction to fire

F

No performance determined

Documents: CEN/TC 12 7/N 1 2 5

Limited spread of flame and smoke production

Documents: Methanamine 'pill' test

Critical flux 1 0 kW m-2. Test: 3 0 minutes. Observation: extent of spread of flame, smoke production. Assess: passlfail Critical flux 4.5 kW m-'. Test: 30 minutes. Observation: extent of spread of flame. smoke production. Assess: pass/fail Extent of damaged area

g X-

'F:

e 3

52 E 3

6

S.

-

L -. o 31 n

5

292


is given if flame spread is less than 550 mm and smoke density does not exceed 30%. 23.11.11 New

developments

Two new standards for testing fire hazards published by lEC/ISO, will be valuable tools to ensure international standardization of test methods, protocols and procedures, reports the International Electrotechnical Commission (lEC). As part of the lEC 60695-11 series, they will replace the lEC standards 6 0 6 9 5 2-4/0 and 60695-2-4/2 and also the ISO standards 1210 and 10351. They will also harmonize several pre-eminent international standards, including the US standard UL 94 Test for flammability of plastic materials for parts in devices and appliances, and ASTMD635,D3801andD5048. 23.11.12 Analysis

New technology for the determination of additives in polymers has been developed by Shimadzu, after a programme in cooperation with Volkswagen AG. The package includes a unique library of 468 fragment spectra from 174 additives, to make quality control analysis faster, easier and more effective. The system does not require any pretreatment of the sample. It is pyrolysed and all pyrolyte fragments are analysed by GCMS. The data is then reduced to an additive (fragment)-specific ion chromatogram, using re-analysis methods within the package. Ion chromatogram peaks are identified by means of a search of the library records and retention time information. Information on all additive fragments is then grouped together to give a complete determination. A fast, reliable, accurate, and cost-effective method of determination of phthalate levels is claimed by Shimadzu, Japan, a specialist in chromatography and spectroscopy. It uses two analytical methods, HPLC and GC, together, or comparing the UV spectra of the sample with those of a standard, Shimadzu has recorded a total analysis time of 16 minutes on six phthalates using HPLC and can separate phthalates by GC inside eight minutes. Both techniques have been demonstrated to yield accurate and consistent phthalate recovery rates (of 9 3 103%), in a rapid process requiring little manual time and effort. 23.11.13 Surface quality tests 23.11.13.1 Barcol hardness test

The Barcol hardness test is a good indication of cure. Barcol readings will vary with different resin systems; for example, the more resilient resins will normally give lower Barcol readings. The US Department of Commerce Product Standard PS-15-69 and ASTM D3299 indicate that readings should be specified at 90% of the manufacturer's recommendation for a particular cast resin. Laminates containing thixotropic agents and/or antimony trioxide have readings 3-5 units higher. Use of paraffin, synthetic fibre overlays, or an unreinforced gel coat may reduce the Barcol reading by 3-10 units.

Background Information: Legislation and Testing

23.11.13.2 Acetone

293

sensitivity

Not all air-inhibited surfaces can be detected by the Barcol hardness tests. It is recommended that the acetone sensitivity test should also be used, where appropriate. This involves application of a small amount of acetone to the resin surface. The wetted surface is then rubbed lightly with the finger until the acetone has evaporated. If the surface softens or becomes tacky, the resin has not fully cured. 23.11.13.3 Surface analysis A variation of the LORIA test uses new technology to evaluate the surface quality of Class A automotive body panels, eliminating subjective visual methods. It uses a low-intensity visible laser to detect surface deviations and imperfections. The beam is projected and scanned across the area, reflected on screen and captured by a high-resolution video camera. There is no contact with the surface, no stylus and no damage. Low-angle scanning allows study of flat or curved surfaces. During analysis, the scanning process is utilized more than 20 times across the part; data is stored by computer and mathematically reduced by special software to a quantified surface quality number, called 'Ashland Index'. 23.11.14 Colour testing As key end users, such as the automobile industry, become more stringent about the colour-fidelity of mouldings, particularly if they are to match or tone in with bodywork or other colours, it should be noted that the standard test for colour (which is used, where appropriate, in the reinforced plastics industry) is ISO. 105 (B02). This specifies a method for determining the resistance of the colour (of textiles) to action of an artificial light source representative of natural dayUght (xenon fading lamp test). Known as the 'Blue Wool Reference' and developed in the USA, the test method is to expose the colour patterns alongside a series of references of known light fastness, such as pieces of wool cloth dyed with blue dyes to a series of different degrees of fastness. As the pattern fades it is compared with the known references and coded under eight classifications, from 1 = most fugitive to 8 = most resistant. Each coding is twice as resistant as the preceding one. A typical range of pigments for polyester resins scores 7+ for most grades, the lowest reading being 4 - 5 . A dedicated software package developed to meet the need of colour analysis has been introduced by Bio-Tek Kontron Instruments, UK. Named Color View, it enables the user to define basic parameters, such as observation degree and illuminant. The user can also customize an illuminant definition. Colour analysis is achieved using a choice of evaluation modes from an extensive list of options. The colour comparison function in the equipment determines the difference between two samples, calculated according to the evaluation modes selected by the user. A hand-held instrument to measure colour quickly, easily and accurately on almost any type of surface - claimed to be the only such device - has been

294


developed by GretagMacbeth. The ColorEye XTH spectrophotometer makes it possible to measure both sample stepped chips and finished products, so ensuring consistency throughout the processing operation. Unlike heavier instruments, it can easily be used to check the colour at any stage. 23.11.14.1 Colour stability To enhance the prediction of light stability of plastics, the ASTM is revising its Standard D 46 74. Entitled Test Method for Accelerated Testing for Color Stability of Plastics Exposed to Indoor Fluorescent Lighting and Window-Filtered Daylight, determines the resistance to a plastic compound to colour change in a typical office environment, under prevailing illumination conditions. The current test method specifies the use of cool white fluorescent lamps and UVB313 sun lamps. The revision, according to Patrick Brennan, Chairman of the ASTM Subcommittee D20.50 on Durability, responsible for the standard, will admit to the test procedure other types of interior lighting sources, which will allow the method to be used to simulate a number of indoor environments.

23.12 Database A comprehensive database on chemical legislation in 25 countries has been published as a CD-ROM by the United Nations Economic Commission for Europe (UN/ECE). It covers 15 sectors of the industry, including materials in contact with foodstuffs, and transport and labelling of dangerous chemicals. Over 600 text summaries are given, with full references to the original legislative acts. Including Directives of the European Community, the database is intended to provide useful information and guidelines for countries worldwide that still have little or no legislation controlling chemicals. It also provides manufacturers, traders, legislators, and lawyers with instant access to information that is normally difficult to obtain.

APPENDIX A Conversion Tables Standard SI units and their derivatives Quantity

Special name

Symbol

Other recognized units

Multiples

Relations

Area

-

m2

Volume

-

m^

a (are), ha (hectare) litre

la=102m2, Iha^lO^m^ 1 litre = 1 dm^

Mass

-

kg

tonne

dm^, cm^, mm^ dm^ cm^, mm^ Mg, g.mg, mg

Linear density

-

kgm"'

tex

Density

-

kgm~^

Time

Frequency Velocity Acceleration Force Pressure Stress

s

l t e x = l()-^kgm-' = 1 gkm"^ kgdm'^ gcm~^

min (minute), h (hour), d (day)

Hertz

Hz

-

ms^^ ms"^

Newton Pascal

N Pa

bar

Pascal

Pa, N m-2

N tex-i

J

eV, kWh

Energy, work Joule quantity of heat Power Watt Viscosity Temperature Celsius Linear coefficient of expansion Thermal conductivity Heat transfer coefficient

lHz= I s ' I k m h - i = 1/3.6 m s - '

kmh-i

MPa,GPa, mbar MPa, Nmm"^ kj

W

kW

Pas

mPas

Wm-iR-i W m-^ K-'

1 tonne = 1 Mg

1 N = 1 kg m s~^ Ibar^lO^Pa, 1 Pa = 1 N mm-^ lNtex= lNkmg-\ 1 mPa = 1 N mm"^ lJ=lNm=lWs, l k W h = 3.6MJ 1 W = 1 J S-' 1 Pa s = 1 N s m-2

296


Conversion of US measure to metric US units

Metric

SI units

Length: 1 foot (ft) 1 inch (in) 1 thou

0.3049 m 2.54cm 0.0254mm

25.4mm

Area: 1 square yard 1 square foot 1 square inch

0.8361 m^ 0.0929 m2 6.451 cm^

Volume: 1 cubic yard 1 cubic foot 1 cubic inch

0.7645 m^ 0.0283 m^ 16.387m3

Liquid: 1 gallon (UK) 1 fluid ounce

4.5459 litres 28.4130cm^

Weight: 1 ton 1 pound (lb) 1 ounce (oz)

1.10160 tonnes 0.4536kg 28.349gm^

Force: llbf 1 Ibfin- (psi)

0.457 kgf 0.0703 kgfcm^

4.4482 N 6.8948 kNm

Density: llbft^ llbin-^

16.()18kgm 27.68gcm-^

27.68 Mgm

(1.8°C)+32 251.996gcal 0.00413 cal cm cm"^ s"' °C"'

1.0550 0.1442 Wm"^°C-'

645.16 mm^

28.317dm^

4.5459 dm^

Thermal: op

IBTU 1 BTU ft"^ h^

Appendix A: Conversion Tables Conversion of metric units to US measure Metric units

US

Length: 1 metre (m) 1 centimetre (cm) 1 millimetre (mm)

3.2808 feet 0.3937 inches 0.0393 Zinches

Area: 1 square metre 1 square centimeter Volume: 1 cubic metre

1.1959 yards^ 10.7639 feet^ O.lSSOinches^

1 cubic centimeter

1.3079 yards^ 35.3147feet^ 0.061 inches^

Liquid: 1 litre 1 cubic centimeter

0.2199 gallons (UK) 0.035 3 fluid ounces

Weight: 1 tonne (te) 1 kilogram (kg) 1 gram(g)

0.9842 tons 2.20461b 0.03 53 ounces

Force: Ikgf 1 kgfcm - (psi)

2.2046 Ibf 14.22 3 31bfin -

Density: 1 kg m~ ^ 1 gcm~^

0.0624 lb ft^ 0.0361 Ibin-^

Thermal: °C

SI units

(°F-32)/1.8 241.9BTUinft^^h"i°F 1

1dm

9.8066 N 98.0665 k N m -

418.68Wmm-

297


APPENDIX B Technical Terms

The following are technical terms commonly used in the plastics additives sector: Acetone: Activator: Additives:

Anatase: Antimony trioxide: Aromatic hydrocarbon: Aspect ratio: Brookite: Catalyst: Complementary colours: Copolymerization: Coupling agent:

co-product with phenol in cumene oxidation process, building block in methyl methacrylate and bisphenol A, used in solvents. (also called an accelerator or promoter) a chemical compound used with a catalyst to permit polymerization at room temperature. the term used for a large number of specialist chemicals that are added to resins/compounds to impart specific properties (such as flame retardancy, impact improvement, UV resistance). a crystalline form of titanium dioxide (Ti02) in which every TiOf, octahedron in the crystal lattice has four edges common to other TiO^ octahedra. a commonly used flame-retardant additive for plastics, especially polyesters. a hydrocarbon chain with a benzene ring. the length/diameter ratio of a particle or fibre. A crystalline form of titanium dioxide (Ti02) in which every TiOe octahedron in the crystal lattice has three edges common to other TiO^ octahedra. (also called hardener) a chemical compound (usually an organic peroxide) which initiates polymerization of a resin. mixed or spectral colours that together appear white. incorporation of more than one monomer into a polymer chain. a substance that promotes or establishes a stronger bond at the resin matrix/reinforcement interface.

300


the process of hardening of a thermosetting resin (by cross-linking of the molecular structure), under the influence of heat and/or curing agents. chemical compounds used to cure thermosetting resins. Curing agents: Curing time: the time taken for a resin to cure (polymerize) to its full extent. With a cold-curing resin, the time is measured from addition of either activator or catalyst. Curing time can be influenced by other chemical aids - retarder or accelerator. Did: a dihydric alcohol. Dye: intensely colouring substances which, when applied to a substrate, impart colour to it by a process which at least temporarily destroys any crystal structure of the colouring substances. oriented growth of crystals from two difl'erent minerals. Epitacy: The epitaxy relates to the considerable analogy of the structures of the partners. Ester: a compound produced by reaction between an acid and an alcohol. Esterification: condensation of acids with alcohols. Exotherm/ a polymerization reaction that generates heat/description exothermic: ofreaction. Fibre: a unit of matter of relatively short length, characterized by a high ratio of length to thickness or diameter. Filament: a single textile element of small diameter and very long length, considered as continuous. Filler: material (usually low-cost) added to a resin to extend it, or give special properties. Flow: the movement of a plastic compound, thermosetting or thermoplastic, under heat and pressure, to fill a mould. Gel: the state of a resin that has set to a jelly-like consistency, solid, but not yet hard. Goniospectral a colorimetric instrument which in increments of (e.g.) 1 photometer: nm in a wavelength range of 3 5 0 - 7 0 0 nm from the whole visible spectrum, reproduces the reflected light of a sample depending on the angle of incidence. Haematite: red-brown a-Fe203 with a corundum structure, the most stable form of iron (III) oxide. Hardener: see Catalyst. saturated dicarboxylic acid anhydride, containing HEX acid anhydride: chlorine. a resin or reinforcement made from two or more different Hybrid: polymers or reinforcement materials. decomposition of chemical compounds by water. Hydrolysis: a technically important titanium mineral (FeTiOs). Ilmenite: saturation of reinforcement with a liquid resin. Impregnation: Cure:

Appendix B: Technical Terms

Inhibitor: Interface: Interference:

Interphase: Light initiator: Magnetite:

Monoester: Monomer: Optical density:

Peroxides: Pigment:

Plasticizer: Polycondensation: Polyester: Polymer: Polymerization: Promoter: Reactive resins: Refractive index: Release agent:

301

an additive that retards or prevents chemical reactions (such as cure). the contact area between reinforcement and matrix resin. superimposition of oscillations and waves. Light waves can interfere when they are coherent (i.e. when they are split by reflection, refraction or diffraction from one and the same wave train). the area surrounding the interface, extending into the matrix resin area. a compound that starts a reaction by being activated by light. the most stable form of iron with an inverse spinel structure Fe"Fe2^04, strongly ferromagnetic. It occurs in nature as black magnetic iron ore (loadstone). a simple ester. a compound containing a reactive double bond, capable of polymerizing or copolymerizing. in an optically more dense medium the speed of light is slower than in a less dense medium. The refraction of a ray of light occurs at the crossover from an optically less dense to a more dense medium towards the perpendicular of incidence; at the crossover from an optically more dense to a less dense medium it occurs away from the perpendicular ofincidence. oxygen-rich compounds used to cure polyester resins. intensely colouring substances usually applied in vehicle and retaining to some degree their crystal or particulate structure. Some pigments have the additional value of conferring magnetic or corrosion protection properties. a chemical compound added to some plastics to render them softer or more flexible. preparation of polyesters with liberation of water. the usual term for an unsaturated polyester resin. a long-chain molecule, consisting of many repeating units. the chemical reaction (linking of monomers) to produce a polymer. see Activator. liquid resins which can be cured by catalysts and hardeners to form solid materials. according to Snell's law, during refraction the quotient of the sine of the angle ofincidence 8 and the sine of the angle of refraction 8 remains constant. a substance which prevents a moulding from sticking to the mould surface, thus facilitating its release from the mould after curing; also known as a parting agent: it may

302


Room temperature: Rutile: Separating compound: Sink mark:

Styrene: Thermoplastic: Thermoset:

Thixotropy: Viscosity: Wet-out:

be a chemical compound or a solid material such as a cellulose or plastics film. room temperature (RT) is taken as 20°C (68°F). A crystalline form of titanium dioxide (Ti02) in which every TiOe octahedron in the crystal lattice has two (opposite) edges common to other TiOe octahedra. see Release agent. a depression on the surface of a moulding, usually caused by local internal shrinkage associated with variation in thickness (frequently can occur on the 'good' side of a moulding, where there is a rib or boss on the underside). an unsaturated monomer, widely used with polyester resins. a plastic that softens each time it is heated. a plastic that flows and then sets permanently on first heating, as a result of setting up a three-dimensional cross-linked molecular structure, and subsequently will not soften or dissolve. the ability of resins to change their viscosity, liquefying on being shaken or stirred. the resistance of a Hquid to flow (and therefore to mixing/ processing); high viscosity is thick, low viscosity is thin. complete wetting/saturation of a particulate or fibrous surface with a resin or carrier.

Standards and Testing Institutions

The following are the commonly encountered abbreviations designating the standards and tests operated by the leading world institutions: ANSI AS ASTM BS CSE DIN DS FAR FMVSS ISO JIS NEN

American National Standards Institute, USA Standards Association of Australia, Australia American Society for Testing and Materials, USA British Standards Institution, UK Centro Studi ed Esperienze dei Vigili del Fuoco, Italy Deutsches Institut fiir Normung eV, Germany Dansk Standardiseringsrad, Denmark Federal Aviation Regulations, USA Federal Motor Vehicle Safety Standard, USA International Standards Organization Japanese Industrial Standards Committee, Japan Nederlands Normalisatie-Institut, The Netherlands


NF NS ONORM SABS SFS SI SIS UL ULC UNE UTE VDE

303

Association Frangaise de Normalisation, France Norges Standardiseringsforbund, Norway Osterreichisches Normungsinstitut, Austria South African Bureau of Standards, South Africa Suomen Standardisoimisliitto r.y., Finland Standards Institution of Israel, Israel Sveriges Standardiseringskommission, Sweden Underwriters' Laboratory Inc., USA Underwriters' Laboratory of Canada, Canada Instituto Nacional de Racionalizacion y Normalizacion, Spain Union Technique deFElectricite, France Verband Deutscher Electrotechniker e.V., Germany

Recommended Books and Journals

For additional reading on specific topics, the following books are particularly recommended: Advanced materials: source book and directory (annual: Elsevier Advanced Technology) Composites - a profile of the worldwide reinforced plastics industry market and suppliers (Elsevier Advanced Technology) Data book ofthermoset resins for composites (Elsevier Advanced Technology) Handbook for plastics processors (J A Brydson; published by Heinemann Newnes/ PRI) Handbook ofplastic and rubber additives (Gower) Handbook of polymer composites for engineers (ed. Leonard HoUaway, published by Woodhead) International plastics handbook (H-J Saechtling, published by Hanser) Plastics engineering handbook of the Society of the Plastics Industry (ed. Michael L Berins, published by Van Norstrand Reinold/SPI) Polymer engineering principles (Richard C Progelhof and James L Throne, published by Hanser) Polymer science and technology of plastics and rubbers (Premamoy Ghosh, pubUshed by Tata McGraw-Hill) SMC - Sheet moulding compounds, science and technology (ed. Hamid G Kia, published by Hanser)

Manufacturers'

handbooks

There is also a wealth of information contained in literature produced by manufacturers and suppliers.

304


journals covering additives for plastics and rubber

Argentina Plasticos Magazine, Salguero 1939, 1425 Buenos Aires Australia Plastics News International PO Box 2 1 3 1 , St Kilda W 3182 Austria OsterreichischeKunststojf-Zeitschrift, Ebendorfer StraSe 10, A-lOlO Vienna Belgium Plastics and Machinery News, Av Carsoel 1268, B-1180 Brussels Brazil Journal de Plasticos, Rua Miguel de Frias 88-Gr 804, 24220-Niteroi Rio de Janiero Plasticos em Revista, Rua Piaui 1164 - Casa 8,01241Sao Paulo - SP China (Republic) China Plastics and Rubber, 21/F Tung Wai Commercial Building, 1 0 9 - 1 1 1 Gloucester Road, Hong Kong Denmark Plast Panorama Scandinavia, Struenseegade 7-9, 2200 Copenhagen N Finland Muoviyhdistys Tiedottaa, Mariankatu 26, SF-00170 Helsinki France Plastiques Modernes etElastomeres, 4:2 ruedes Jeuneurs, F-75002 Paris Plastiques et Caoutchoucs, 5 rueJulesLefebvre, 75009 Paris Plastiques Flash, 78 Route de la Reine, F-92100 Boulogne/Seine Germany Gummi Fasern und Kunststojfe, Dr Heinz Gupta Verlag GbR, Postfach 10 41 25, D-40852Ratingen K-PIflsiic2dii/n^,AufderHeide 20, Postfach 12 01 6 1 , D-30916Isernhagen Kunststoffe, Marburgerstrasse 13, D-64289 Darmstadt Kunststoff'Information, SaalburgstraGe 15 7, D-61350 Bad Homburg Kunststojf Journal, Thomas-Dehler-StraEe 27, Postfach 83 03 5 1 , D-81737 Munich 83 Plastics Industry Europe, Saalburgstrafi 157, D-613 50 Bad Homburg Plastverarbeiter, Im Weiher 10 Postfach 10 28 69, D-69018 Heidelberg Prodoc-Kunststojftechnik, Postfach 40 06, D-6100 Darmstadt


305

India Popular Plastics, 126 A, Dhurwadi, off Dr Nariman Road, Prabhadevi, Bombay 400 02 5 Italy Industria della Gomma, Via C Battisti 21,1-20122 Milan Macplas, Centro Commerciali Milanofiori, 1 Strada - Palazzo F/2, 1-20090 Assago/MI Materie Plasticine ed Elastomeri, Editrice OVEST Sri, via Simone d'Orsenigo 22, 20135 Milan PoliplastiePlastichiRinforzati, ViaMecenate 91,1-20138 Milan Japan Japan Plastics, Kogyo Chosai Publishing Co Ltd, 14-7 Hongo 2-chome, Bunkyo-ku, Tokyo PlasticsIndustryNewsXentra\FOBoxNoll76,Tokyo 100-91 Netherlands Kunststofen Rubber, Postbus 71, NL-2600 AB Delft Norway Metaal en Kunststof, Postbus 71, NL-7000 BA Doetinchem Norsk Plast, Postboks 235 Skoeyen, N-0212 Oslo 2 South Africa Plastics Southern Africa, PO Box 704, Cape Town 8000 SA Plastinews, PO Box 792, Pinetown 3600 SA Spain Revista de Plasticos Modernos, Juan de la Cierva 3, 28006 Madrid Sweden Plast'Forum Scandinavia, Box 601, S-2 51 06Helsingborg Plast Nordica, Box 91 13, S-250 09 Helsingborg Switzerland Kunststoffe-Plastics, Vogt-Schild AG, ZuchwilerstraEe 2 1 , CH-4501 Solothurn Modern Plastics International, 14 avenue d'Ouchy, CH-1006 Lausanne United Kingdom British Plastics and Rubber, 3 7 Nelson Road, Caterham, Surrey CR3 5PP European Plastics News, PO Box 109, Maclaren House, 19 Scarbrook Road, Croydon CR9 1 OH European Rubber Journal, 20-22 Bedford Row, London WC1R4EW Plastics Additives and Compounding, Elsevier Advanced Technology, PO Box 150, Kidlington, Oxford 0X5 IAS

306


Plastics and Rubber Weekly, PO Box 109, 19 Scarbrook Road, Croydon, Surrey CR9 1 OH Reinforced Plastics, Elsevier Advanced Technology, PO Box 150, Kidlington, Oxford OX5 IAS Technical Textiles International Elsevier Advanced Technology, PO Box 150, Kidlington, Oxford 0X5 IAS United States Modern Plastics, 1221 Avenueofthe Americas, New York, NY 10020 Plastics Engineering, 14 Fairfield Drive, Brookfield Center, CT 06804 Plastics Focus, PO Box 814, Amherst, MA 01004 Plastics World, 2 75 Washington Street, Newton, MA 02158 Plastics Machinery and Equipment, 1129 E 17th Avenue, Denver, CO 80218 Plastics Technology, 633 Third Avenue, New York, NY 10017 PlasticsWeek, 1221 Avenueofthe Americas, New York, NY 10020 Yugoslavia Polimeri, Kaptol 22, YU-41001 Zagreb

APPENDIX C Standard Abbreviations for Plastics and Elastomers

A ABSM

Acrylonitrile/butadiene/styrene

C CA CAB CAP CFC CN CP

Cellulose acetate Cellulose acetate butyrate Cellulose acetate propionate Chlorofluorocarbon Cellulose nitrate Cellulose propionate

E EPDM EPM EPS EVA, EVAC EVOH

Ethylene propylene terpolymer Ethylene propylene copolymer Expanded polystyrene Ethylene vinyl acetate Ethylene vinyl alcohol

F FEP FPM FR

Fluorinated ethylene propylene (also perfluoro ethylene/propylene) Vinylidene fluoride/hexafluoropropylene copolymers Flame retardant

G GP

General purpose

308


H HD HI HMW

High density High impact High molecular weight

L LD LFI LLD

Low density Long-fibre injection moulding Linear low density (polyethylene)

M MD MF

Medium density Melamine/formaldehyde

O OPP

Oriented polypropylene (film)

p PA PAN PBTP PC PE PETP PETG PF PMMA POM PP PS PTFE PUR PVAC PVAL PVC PVDC PVDF PVF

Polyamide (also known as nylon) Polyacrylonitrile, Polybutylene terephthalate (polyester) Polycarbonate Polyethylene, Polyethylene terephthalate (polyester) Polyethylene terephthalate (glycol co-monomer) Phenol/formaldehyde Polymethyl methacrylate (also known as acrylic) Polyoxymethylene (also known as acetal, polyacetal) Polypropylene Polystyrene Polytetrafluoroethylene Polyurethane Polyvinyl acetate (also PVA) Polyvinyl alcohol Polyvinyl chloride Polyvinylidene chloride (also PVdC) Polyvinylidene fluoride Polyvinyl fluoride

R RIM R-RIM

Reaction injection moulding Reinforced reaction injection moulding

Appendix C: Standard Abbreviations for Plastics and Elastomers

s S-PVC

Suspension PVC

U UF UHMW uPVC

Urea formaldehyde Ultra-high molecular weight Unplasticized (rigid) PVC

V VLD

Very low density (polyethylene)

Sources: ISO 1043-1978

(DIN 7 7 28 Parti), DIN ISO 1629, industry practice

309


APPENDIX D Trade Names

A Abril Abril Abril A-C Aclyn Acrawax Aerolite Aerosol Actimer Aetirox Aeumist Adeka Adimoll Advapak Advapak Akrochem Akro Aktisil Albidur Albiflex Albipol Albipox Albisil Alehemix Alfrimalsmall Alkanox Alkasperse Almax Almical Aloxan Alsilanlayered

fatty amide waxes Cosmie polyearboxylic aeid wax Paradigm fatty amide waxes polyethylene copolymer modifiers ionomer pigment dispersants bis-amide wax lubricants organic pigments solvent dyes flame retardants modified zinc phosphate micronized polyethylene waxes additives plasticizers lubricating stabilizers multifunctional stabilizers iron, oxide, red, black, yellow Pakone-pack blends functional fillers silicone toughness improver epoxy/silicone additives polyurethane-based resins epoxy-based resins silicone-based resins fillers, release agents particle reinforcing fillers anti-oxidants, phosphite liquid pigment dispersions alumina fibre semi-reinforcing fillers semi-reinforcing fillers silicate

Abril Abril Abril AUiedSignal AUiedSignal Lonza Acrol Acrol Solem Colores Hispania AUiedSignal Asahi Denka Bayer Morton Int Morton Int Akrochem Akcros Hoffmann Hanse Chemie Hanse Chemie Hanse Chemie Hanse Chemie Hanse Chemie Alchemic Alpha Calcit Great Lakes Colloids Mitsui Alpha Calcit Alpha Calcit Alpha Calcit

312


Alsitalclayered Amgard CPC Amgard N Amgard P Amical Ancamide Ancamine Anox Anquamide Antistatic CB Apicolor Aqualiftmould Armid Armoslip Armostat Armoslip Armowax Atmer Axel Mold-Wiz

silicate FR: red phosphorus, masterbatch FR: phosphates FR: organophosphorus calcium carbonate epoxy curing agent epoxy curing agents antioxidants, phenol epoxy curing agents carbon black antistatic pigment concentrates release agents slip/anti-blocking agents slip agents antistatic agents anti-slip, anti-blocking agents impact modifiers anti-fogging agents, antistatics mould release agents

Calcit Albright & Wilson Albright & Wilson Albright & Wilson KMG Minerals Air Products Air Products Great Lakes Air Products Inducolor API Dexter Akzo-Nobel Akzo-Nobel Akzo-Nobel Akzo Nobel Akzo-Nobel Ciba Axel

B Baco ATH Baropol Bayfomox Bayplast Bewaxmould BFR Binisil Black Diamond Black Pearls Bloomgard Brancolor Bruggolen C Bruggolen F Bruggolen H Bruggolen L Bruggolen M Bruggolen P BurnEx Busanll-M2

flame retardants additive systems flame retardants pigments release agent blended flame retardants silicone lubricant masterbatch carbon black dispersions carbon black granule flame retardants additive/colour concentrates additives for cast nylon flame retardants heat stabilizers weathering agents impact modifiers, plasticizers lubricants, mould release agents flame retardants barium metaborate

BYK BYK-A BYK-WBMC

styrene emission suppressants air release for polyester resins wetting/dispersion agents

Alcan Chemicals Barlocher Bayer Bayer Diversey Anzon Micropol Chinghall Cabot Great Lakes Branco Briiggemann Briiggemann Briiggemann Briiggemann Briiggemann Briiggemann PO Corporation Buckman Laboratories Byk Chemie Byk Chemie Byk Chemie


c

313

Cabelec Calcilit Calciplast Capow Casabond Casamid Casastablatex Catafor Cereclor

electrically conductive masterbatch high purity calcium carbonates high purity calcium carbonates powder coupling agent bonding agents non-reactive polyamides thickening agents anti-static agents chlorinated paraffins, FR agents

Charmax Chemica Chimassorb Chlorezflame Chromoflo Clean-Wiz

flame retardants reinforcing filler (mica) light/UV stabilizers retardants pigment dispersions (low vise) cleaning, stripping agents

Coatex Coathylene Colormatch Colour Diamond Combibatch Comistab Conbio Condeg Conduct-o-Fil Conselect Constab Constab Colour Corducell Cordulen CordumaUV Cordustat Crodamide Cryoflex Cyanox Cyasorblight

phosphoric ester dispersing agents microfine thermoplastic powders pigment dispersions pigment dispersions additive/colour masterbatches stabilizers agricultural film masterbatches degradable additive masterbatches conductive additives special agricultural masterbatches additive masterbatches pigment/dye masterbatches chemical blowing agents slip/anti-block/antioxidants/FR stabilizers anti-statics fatty acid amides plasticizers anti-oxidants stabilizers

Cabot Alpha Calcit Alpha Calcit Kenrich Thomas Swan Thomas Swan Thomas Swan Rhone-Poulenc ICI ChlorChemicals Marshall Incemin Ciba-Geigy Dover Plasticolors Axel Plastics Research Coatex Herberts Polymer Plasticolors Chinghall Sarma Comiel Constab Constab Potters-Ballotini Constab Constab Constab Nemitz Nemitz Nemitz Nemitz Croda Sartomer Cytec Cytec

D Dantosperse Dechlorane Plus Dehydrat Denka Denka Malecca

hydantoin ester dispersants chlorinated anti-static, anti-fogging agents fused silica silica filler maleimide copolymer

Lonza FROccidental Henkel Mitsui Mitsui

314


Deplastol Deltaplast Deltavinil Devolite Dicalite Dimodanhigh Diolpate Diplast Disflamoll Disperplast Dolofil DorkafiU Dovernoxsolid Doverphos Drapex Dualite Duhor Durawool

plasticizer masterbatch colour masterbatch for PVC medium-size alkaline china clay diatomite, perlite functional fillers concentration anti-statics polymeric plasticizers PVC plasticizers flame retardants/plasticizers wetting and dispersion additives calcium/magnesium carbonate fillers china clay extenders anti-oxidants organophosphites epoxidized stabilizers polymeric microspheres magnesium hydroxide FR steel wool (fibres)

Dyhard Dyhard Dynamar Dynol

curing agent, powder coatings epoxy resin accelerators polymer processing additives PVAl wetting agent

E Eastobrite Ecosphere

optical brightening agent hollow glass microballoons

Edenol Elastolor Elbaplast Electrafil Elftex Elvaloy EMAC

plasticizers thermoplastic elastomer additives solvent dyes conductive compounds carbon black powder and granule plasticizers impact modifier/compatibilizer

Emopasta Endex Epilink

pigment concentrates additives epoxy curing agents

Epodil Epolene Esperaldicumyl EsperfoamMEK Esperox

epoxy modifiers coupling agent/compatibilizer peroxide peroxide peroxyester

Henkel Deltacolor Deltacolor ECC Redland Danisco Kemira Polymers Lonza Bayer Byk Chemie Redland Dorfner Dover Dover CKWitco Pierce & Stevens Duslo a s Sala Overbeck Handelsges SKWTrostberg SKWTrostberg 3M Air Products

Eastman Emerson & Cuming Henkel Plasticolors HoUiday Chemical DSM Cabot Erbsloh Chevron Chemical Inducolor Endex Corp Air Products (prev. Akzo) Air Products Eastman Witco Witco Witco


315

Eupolen Evatane Exocerol

organic pigments modifiers/processing aids exothermic blowing agents

Exolit Expancel Expansor Exterplast Exxelor

flame retardants thermoplastic microspheres blowing agents monomeric plasticizers polyolefinic modifiers

BASF ElfAtochem Boehringer Ingelheim Clariant Expancel Repi Coim Exxon

F Faradex FF680 Fiberglas Filolencalcium Firebrake ZB Firemaster Fireshield Flamtard S Flamtard Flanagen Fleka Flexaryl Fordacal FRCROS FR-930 Frekote FS Ftalidap Fyreblocflame Fyrol

conductive compounds bis(tribromophenoxy)ethane glass fibre carbonate masterbatch zinc borate flame retardants antimony oxide FR zinc stannate magnesium, zinc borate FR azodicarbonamide blowing agents granulated glass flake extender for PU and epoxies high-whiteness marbleE ammonium polyphosphate flame retardants mould release agents Systems stabilizers phthaUc anhydride retardants flame retardants

DSM Great Lakes Owens Corning Chrostiki US Borax Great Lakes Laurel Industries Alcan Chemical Alcan Chemicals Inbra Industrias NGF Europe Monsanto CC Anzon Akzo-Nobel Frekote Ciba-Geigy Lonza Great Lakes Akzo-Nobel

G GADDS Garbefix Geniset Genitron Geode Getren Giadds Glicogum Glycolube Glycomul Glycosperse

modifiers for PVC, eng. plastics phosphite anti-oxidants nucleating agents blowing agents inorganic pigments release agents PVC modifiers, processing aids rubber auxiliaries lubricants/release agents emulsifiers, slip agents, dispersants PVC antistatic/anti-fog agents

Gharda Chemicals Great Lakes Hoechst Bayer Ferro Goldschmidt Gharda Chemicals Great Lakes Lonza Lonza Lonza

316


Glycostat Granufin Grinitmast Grinitmicro Grinitpearl Grinitpulv Grinsted Mono Grinsted PGE Grinsted SMS Grit-0'Cobs GTY H Heliogen Hercules Hexafil Hexafort HiMod Hi-Sil Hispafos SP Hombitan Hordaresin Hostaflam Hostalub Hostamont Hostanox Hostaprime Hostastat Hostavin Hybon Hycite EXM Hydrosodium Hydrocarb Hydrocerol

I ICAliquid Iceberg Icecap K Idrosow Imicure Inbraflex Incoblend

anti-static, anti-fog microgranule carbon pigments pellet masterbatches micronized masterbatches microballoon masterbatches non-dusting powder masterbatches anti-static/cling agents polyglycerol ester anti-fog agent sorbitan ester antifog agent cellulose extender medium-size china clay

phthalocyanine pigments graphite fibres ball clays ball clays mica reinforcing silicas for rubber small particle zinc phosphate titanium dioxide pigments flame retardants FR agents waxes, lubricants release agents anti-oxidants coupling agents/compatibilizers antistatics HALS benzophenone stabilizers glass fibre roving stabilizers hydrosulphite ultrafine calcium carbonate blowing and nucleating agents

coupling agents calcined clays aluminium silicates colour pastes epoxy curing agents epoxidized soyabean oil concentrated conductive polymer

Lonza Brockhues Grinit Plast Grinit Plast Grinit Plast Grinit Plast Danisco Danisco Danisco Andersons ECC

BASF Hercules ECC ECC KMG Minerals PPG Colores Hispania Sachtleben Dover Hoechst Clariant Clariant Clariant Hoechst Clariant Clariant PPG Sud-Chemie Transpek Omya Boehringer Ingelheim

Kenrich Burgess Pigments Burgess Pigments Repi Air Products Inbra Industrias Zipperling Kessler


317

InFilm Intercide Interlite Interox Interstab Interwax Irgaclear Irgafos Irganox Irgasan Irgastat Irgazin

anti-blocking agents anti-microbial additives PVC stabilizers organic peroxides PVC stabilizers lubricants clarifying agents processing stabilizers anti-oxidants/heat stabilizers anti-microbials anti-static agents pigments

ECC Akcros Akcros Peroxid-Chemie Akcros Akcros Ciba Ciba Ciba Ciba Ciba Ciba

Jaycaswax 100 Jaycaswax Jaycopls Jaylubes Johoku UV

lubricants/dispersing agents lubricants, slip/anti-block agents coupling agents lubricants/anti-fogging agents UV absorber

Jayant Jayant Jayant Jayant Mitsui

K Kadox911

zinc oxide

Kane Ace Kane Ace-B Kane-Ace PA Kanstick Kapronet Kemgard Ken-React Ken-Stat Ketjen black EC Kevlar Ketjenblack Kosmos Kotamide Kronitex Kronos KSS

FM weather-resistant impact modifiers impact modifiers MMA processing aid for PVC external mould release agents purging compound zinc phosphates, silicates coupling agents coupling agents conductive carbon black aramid fibre special carbon black tin catalysts coated calcium carbonate natural phosphate flame retardants titanium dioxide flame retardant

Zinc Corp. of America Kaneka, Mitsui Kaneka, Mitsui Mitsui Specialty Products GE Plastics Sherwin Williams Kenrich Kenrich Akzo-Nobel DuPont Akzo Nobel Goldschmidt ECC Great Lakes Kronos Seal Sands

Lankroflex Lankromark

speciality plasticizers liquid PVC stabilizers

Akcros Akcros

Oil Mills Oil Mills Oil Mills Oil Mills

318


Latha Lazer Flair Leucopur Levagard Lightfast Lipinol Listabmetal Lithol Lithopone Lonzacure Lonzest Lotader Lotryl Lowilite Lowin Loxamid Loxiol LSFR Lubriol Lubristat Lumogen Luperox Luzenac Lysopac

carbon black, activated carbon laser-marking additive optical brighteners flame retardants pigments viscosity depressant stearates pigments zinc sulphide pigments aromatic amine chain extenders sorbitan ester anti-static/anti-fog agents modifiers/processing aids EMA/EBA modifiers/processing aids light/UV stabilizers oxanti-oxidants lubricants, slip agents dispersing aids. low smoke flame retardant lubricants lubricant dyes organic peroxides talc organic pigments

Latha Chemical EM Industries Sarma Bayer Bayer Hills Chemson BASF Sachtleben Lonza Lonza Elf Atochem Elf Atochem Great Lakes Great Lakes Henkel Henkel Laurel Industries Comiel Comiel BASF Luperox Luzenac Cappelle

M Macrolex Magnesia Magnifin MagShield Marbocote Markep Marklube Markstab Markstab Markstat Martinal Masterad Mastersafe Mastertint Mastertint Matchwel MatVantage Maxithen Maxwhite

pigments magnesium oxide magnesium hydroxide FRs flame retardant release agents oxidized compounds, lubricants lubricants organic phosphites PVC liquid stabilizer anti-static agents aluminium trihydrate FRs anti-slip, anti-static masterbatch aluminium pigment concentrate pigment masterbatch colour masterbatches colour concentrates continuous strand mat colour masterbatches calcined china clay

Bayer Magnesia Lonza Martin Marietta Zychem Witco Witco Witco Witco Witco Lonza Chrostiki Obron Atlantic Chrostiki Krostiki Hawley PPG Gabriel 20 Microns


Mearlin Melax

lustre pigments mould conditioners, sealants

Menatalc Meramid, Arax Mesamoll Metablen Microglas Micron Microtalc Microtem Mikhart Mikrobrite Mikrofine

magnesium silicates rubber curing accelerators speciality plasticizers impact modifiers glass flake talc, barytes, calcium carbonate mirconized talc white calcite calcium carbonate calcined chalks additives

MikroXtra Millad Millicarb Minfil Miralex Mistron ZSC

calcined chalks clarifying agents for PP calcium carbonate white calcites twin-form glass fibre talc

Modifix Mogul Mold-Wiz

processing aids carbon black powder lubricants, release agents

Monarch Mono-Pak

carbon black powder additive packages

N Naftolube Naftomix Naftosafe Naftovin Neviflam Nevimaster Nevisylon Nicalon Norpol Noury

PVC lubricants stabilizer/lubricant systems stabilizer/lubricant systems heat/Ught stabilizers self-extinguishing masterbatches colour/additive masterbatches anti-sticking agent silicon carbide fibre resins, gelcoats, fillers bond adhesion promoters

Nourymix Nyad Nyglos Nylostab

additive concentrates woUastonite (untreated) ultrafine woUastonite light stabilizers

319

Mearl Axel Plastics Research Dorfner Great Lakes Bayer Elf Atochem NGF Europe 20 Microns 20 Microns Redland Provencale Faxe Kalk High Polymer Labs Faxe Kalk Milliken Omya Redland Owens-Corning CyprusInd Minerals Sarma Cabot Axel Plastics Research Cabot Catalyst Systems

Chemson Chemson Chemson Chemson Nevicolor Nevicolor Nevicolor Mitsui Jotun Polymer Air Products (prev. Akzo) Akzo Nobel Nyco Minerals Nyco Minerals Clariant

320

Additives fur Plastics Handbook

o Omya Omyalene Oncor Ongard Optiwhite Oracet Orevac Orgamin Ortegol

calcium carbonate dispersion agent flame retardants flame retardants calcined aluminium silicates polymer-soluble colorants modifiers/processing aids lead-free decorative pigments wetting/softening agents

Omya Omya Great Lakes Great Lakes Burgess Pigments Ciba Elf Atochem Colores Hispania Goldschmidt

P Paliotol Paraflint Paraloid Pationic Pepton Pergan Pergosperse Petcat Phthalotint Pionier Plasadd Plasblak Plasgrey Plastabil

pigments Fischer-Tropsch waxes MBS/acrylic impact modifiers internal lubricants peptizers organic peroxides polyethylene glycol dispersants polyester antimony catalyst pigment dispersions lubricants additive masterbatches black masterbatch grey masterbatch PVC stabilizers

Plastigel Plastipasta PlastiStab Plastolein Plastolor Plaswite Plaxter Polarite Polastech Polcarb PoleStar Polimix Polyace Polyad Polyaldo Polymekon Polymica Polyplastol

SMC/BMC thickeners pigment concentrates mixed metal heat stabilizers low-temperature plasticizers additive concentrates white masterbatch PVC polymeric plasticizers treated calcined clays technical masterbatch fine/ultrafine calcium carbonates calcined clays, metakaolin PVC plasticizers copolymers preblends polyglycerol ester dispersants EPS defoamers mica rubber processing promoters

BASF Schumann Sasol Rohm and Haas Patco Thomas Swan Pergan Lonza Laurel Industries Krostiki Dahleke Cabot Cabot Cabot Diadema Industrias Plasticolors Inducolor OM Group Henkel Plasticolors Cabot Coim ECC Cabot ECC ECC Lonza AlUedSignal Ciba Lonza Goldschmidt KMG Minerals Great Lakes


321

Polytint Polyvel Porofor PP1345

pigment concentrates melt flow modifiers, concentrates blowing agents chopped glass fibre for PA, PP

Preadd Prelux Premier Prestige Primax Primglos Priplast Pripol Pripol Pyro Chek

additives colour control system ultramarine pigments ultramarine pigments surface-modified UHMW PE ultrafine wollastonite PVC plasticizers, polyol additives dimer acid modifying agents polyurethane additives flame retardants

Krostiki Polyvel Bayer GlassTech Scandinavia Premix Oy ColorMatrix HoUiday Pigments Holliday Pigments Air Products Nyco Minerals Unichema Unichema Unichema Erbsloh

Ouartzel Oueensfil Quickset

fused quartz yarn chalk whitings MEKP

Quartz & Silice ECC Witco

R Rainbow Rakusol Reablend Reactint Readd Reaflakes Reagens Realube Rea-tin-or Recycloblend Regal Remap Reofos Reomol Repiplast Replas Repsil Reseda Reversacol Rhenodiv Rhodialux Rhodianox

coloured masterbatch liquid colours stabilizers, lubricants for PVC reactive colourants polyurethane adducts stabilizers, lubricants for PVC PVC additives lubricants organotin derivative stabilizers stabilizer systems for recycling carbon black powder and granule colour pastes (thermoplastics) phosphate flame retardants flame retardants colour pastes (PVC, PU) polymeric plasticizers colour pastes (silicon rubber) graft copolymer compatibilizer photochromic dyes release agents benzophone stabilizers phenolic antioxidants

Cabot BASF Reagens Milliken Townsend Reagens Reagens Reagens Reagens Ciba Cabot Repi Great Lakes Great Lakes Repi Townsend Repi Mitsui HolUday Chemical Rhein Chemie Great Lakes Great Lakes

0

322


Ricinolts Ricon Riowax

stabilizers colorants rubber anti-degradants

Jayant Oil Mills Rite Systems Great Lakes

Sachtolith Safe FR 5000 Safoam Safolin Safolite Sandin Sandostab Sanduvor Sanduvor Sanitized Santicizer Sarmacal Sarmacarb Sarmaclean Sarmadrop Sarmaflam Sarmaglass Sarmagrip Sarmagum Sarmalube Sarmalyte Sarmamid Sarmapor Sarmastab Sarmastat Sarmastyr Sarmasyn Sarmatene Sarmatherm Sarmawax Secudur Secupurnu SecurocAFR: SecurocBFR: Securoc CFR: SecurocDFR: Securoc PBT/PP Securoc Polyamide Securoc Resin, Resin Plus

zinc sulphide pigments flame retardants chemical blowing agents zinc formaldehyde sulphoxylate sodium formaldehyde sulphoxylate anti-statics anti-oxidants light stabilizers UV stabilizer anti-microbial agents benzyl phthalate plasticizers calcium carbonate masterbatches colour masterbatches - PC purging agent anti-fogging masterbatch flame retardants colour masterbatches - PMMA anti-slip masterbatch colour masterbatches lubricant for polyamides anti-degradation masterbatches colour masterbatches - PA blowing agent masterbatch heat/light stabilizers anti-static agents colour masterbatches - PS colour masterbatches - PVC colour masterbatches - PO radiation barriers/UV stabilizers anti-slip/anti-blocking/lubricants synthetic woUastonite cleating/anti-blocking agents aluminium hydroxide magnesium hydroxide magnesium/calcium carbonate/hydrate magnesium/calcium carbonate FRforPBT,PP FR for polyamides

Sachtleben Uvitec Inc Reedy Intl Transpek Transpek Clariant Clariant Clariant Clairant Sarma Monsanto Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Sarma Incemin Incemin Incemin Incemin Incemin Incemin Incemin Incemin

FR for thermosets

Incemin


323

Selar Shawinigan Sicomin Sicopal Sicotan Sicotrans Silene Silstrip Slipwax Smokebloc Snowfort Sorbacid EXM Special Diamond Speswhite Sphericel Spheriglas Spinflam Spray-Lite Sprayset Stabilox Stabinex Stabiol Stabiol Star Stran Stat-Kon Stat-Rite Stockalite Stone-Tex Subar Suconox Sukano UV Sulfatran Superox Supreme Surfynol Synchnrolube Syncomat

barrier-forming additives conductive additive organic pigments pigments pigments pigments reinforcing silicas for rubber silicone solvent/remover mould release agents flame retardants calcium carbonate stabilizers additive dispersions ultrafine high-purity china clay hollow glass spheres solid glass spheres halogen-free flame retardants fillers dilute MEKP CaZn lead stabilizer for PVC aZn stabilizers lubricants glass reinforcement conductive compounds anti-static polymer additive alkaline high purity china clay granite effect fillers barium sulphate polyamide antioxidant masterbatches for PET accelerators, curing agents cure initiator ultrafine high-purity china clay surfactants fatty acid ester, stearic lubricants glass reinforcement

DuPont Shawinigan BASF BASF BASF BASF PPG Penn-White Diversey Great Lakes Croxton & Garry Sud-Chemie Chinghall ECC Potters-Ballotini Potters-Ballotini Montell Marshall Witco Henkel Mitsui Henkel Henkel SchuUer LNP Plastics BF Goodrich ECC Marshall Provencale Seal Sands Chemiehandel Transpek Reichhold ECC Air Products Croda Syncoplas

T Tafmer Tecfil Technora Tegiloxan Tego AB-M Tego Antiflamm

elastomer modifier for polyolefins ceramic microspheres aramid fibre release agents chemical blowing agents flame retardants

Mitsui Filtec Mitsui Goldschmidt Goldschmidt Goldschmidt

324


Tego Conduct Ultra Tego Entschaumer Tego RC Tegoamin Tegocolor Tegokat Tegopren Tegosil Tegosipon Tegostab Tegotens Tegotrenn TekNeonLite Tenax Tersar Tersar ThermalGraph Thermoguard S Thermoplast Thornel Timonox Tinstab Tint-Ayd TinuvinUV Tinuvin TiONA Tital Topanol Tospearl Tracel Transcure Trapex Trawax Triacetin/Tegda Tudalen Turmosil Turmsilon Twaron Twintex

semiconducting tin dioxide PVC defoamer release coatings amine catalysts colour pastes glycerol fatty acid esters process auxiliaries release agents deaerators PU foam stabizers glycerol fatty acid esters release agents colorants carbon fibre colour masterbatches PET optical brightener carbon fibre antimony oxide dyes pitch-based carbon fibres antimony oxide PVC stabilizers (tin) pigment dispersions absorbers, HALS light/heat stabilizers titanium dioxide reinforcing filler anti-oxidants silicone anti-blocking agent blowing agents accelerators, curing agents lubricants, release agents lubricants, release agents plasticizers plasticizers silicone-free release agents/lubricant silicone release agents/lubricant aramid fibre commingled glass fibre

Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Goldschmidt Teknor Color Akzo Sarma Sarma BP Amoco AtoChem BASF BP Amoco Anzon Akcros Daniel Products Ciba Ciba-Geigy SCM Chemicals Incemin Seal Sands GE Silicones Tramaco Transpek Tramaco Tramaco Bayer Dahleke Consult Consult Akzo Vetrotex

U Ultrafibe Ultrafine Ultramoll Unicell

surface-treated wollastonite antimony oxide FR plasticizers chemical blowing agents

Nyco Laurel Industries Bayer Tramaco


325

Unifilo Unimax Unimoll Uniplex Unislip United Unitex Univul Univul Univul Uniwax UV Chek Uvasil Uvitex

continuous strand glass mat colour concentrates plasticizers flame retardants slip/anti-block agents carbon black granule optical brighteners light stabilizers and anti-oxidants light stabilizers, UV absorbers light stabilizers, UV absorbers slip/anti-block agents light stabilizers HALS light/UV stabilizers optical brightening agents

Vetrotex Gabriel Bayer Unitex Corp Unichema Cabot Ciba BASF BASF BASF Unichema Erbsloh Great Lakes Ciba-Geigy

V Valu-Fil Variocrom Versicon Vetrotex Vibatan Vinylube Viscobyk Vulcabond Vulcan

calcium sulphate colour-variable pigments conductive polymer glass fibre range of additives ester anti-static/anti-fog/lubricants viscosity depressants for plastisols PVC bonding agents carbon black powder and granule

Marshall BASF Zipperling Kessler Vetrotex Viba Lonza Byk Chemie Akcros Cabot

W WG325 Wollastocoat

mica, wet-ground surface-modified wollastonite

KMG Minerals Nyco Minerals

X Xantrix

additive delivery systems

Montell

Y Y-200 YLO-2288D

high-conductivity acetylene black iron oxide, yellow

SN2A Pfizer

Zerogen 35

magnesium hydroxide

Solem Divn J M Huber


APPENDIX E Directories Directory of suppliers

3M Specialty Fluoropolymers Department, 3M Center, Building 220-lOE-lO, St. Paul, MN 55144-1000, USA; tel: +1-612-733-6760; fax: +1-612-7377686 3M European Chemical Business Center, 3M (Antwerp) Belgium SA/NV, Canadastraat, B-2070 Zwijndrecht, Belgium; tel: +32-3-2 52-0711 3M Nederland BV, Industrieweg 24, NL-2382 NW Zoeterwoude, The Netherlands; tel:+31-75-5540-450; fax:+31-71-5540-212 A ABB Industry Oy, PO Box 184, FIN-00381 Helsinki, Finland; tel: +358-10-2223281; fax:+358-10-222-2681 ABB-IR Waterjet Systems AB, PO Box 2, Chorley New Road, Bolton BL6 6JN, UK ABC Group Ltd, 100 Ronson Drive, Rexdale, Ontario M9W 1B6, Canada; tel: + 1-416-246-1782; fax:+1-416-246-1552. Abril Industrial Waxes, Sturmi Way, Village Farm Industrial Estate, Pyle MidGlamorgan CF33 6NU, UK; tel: +44-1656-744-362; fax: +44-1656-742471 AC Technology Europe, PO Box 545, 7500 AM Enschede, The Netherlands; tel: + 31-53-836331; fax:+31-53-836332 Accrapak Systems Ltd, Burtonwood Industrial Centre, Warrington WA5 4HX, UK ACE Industrial Plastics Ltd, Brittania House, Lockway, Ravensthorpe Industrial Estate, Dewsbury, West Yorkshire WF13 3SX, UK; tel: +44-924-492244; fax:+44-924-490334 Acrison International, 20 Empire Boulevard, Moonachie, NJ 07074, USA; tel: + 1-201-440-8300; fax: +1-201-440-4939 Acrol Ltd, Everite Road, Ditton, Widnes WA8 8PT, UK; tel: +44-151-424-1341; fax:+44-151-495-1853 Additive Polymers Ltd, Unit 4 Kiln Road, Burrfields Road, Portsmouth P03 5LP, UK; teh+44-1705-678-575; fax:+44-1705-678-564 Addmix, Unit 20, Cygnus Business Centre, Dalmeyer Rd, London NWIO 2XA, UK; tel:+44-181-459-7477; fax:+44-181-459-7433

328


Advanced Ceramics Corp, 11907 Madison Avenue, Lakewood, OH 44107, USA; tel:+1-215-529-3964; fax:+1-216-529-3954 Advanced Elastomer Systems NV/SA, Avenue de B(31e 1, Bazellaan, 1140 Brussels, Belgium; tel:+32-2-706-3311; fax:+32-2-76-3310 Advanced Elastomer Systems, 260 Springside Drive, Akron, OH 44334, USA; tel:+1-216-668-3763. Advanced Surface Technology Inc, 9 Linnell Circle, Billerica, MA 01821-3902, USA; tel: +1-508-663-7652; fax: +1-508-663-7746 AESJapan; tel:+81-3-3584-9341; fax:+81-3-3584-9342 Agema Infrared Systems Ltd, Arden House, Leighton Buzzard LU7 7DD, UK; tel:+44-1525-375660; fax:+44-1525-379271 Air Products and Chemicals de Mexico SA de CV, Rio Guadiana 23 piso 5, Colonia Cuauhtemoc, Mexico DF 06500, Mexico; tel: +52-5-546-7064/ 0415;fax:+52-5-592-3018 Air Products and Chemicals Inc, Polymer Chemicals, 7201 Hamilton Boulevard, AUentown, PA 18195-1501, USA; tel: +1-610-481-6799; fax: +1-610481-4381 Air Products Chemicals Division - Europe, PO Box 3193, NI-3502 GD Utrecht, TheNetherlands; tel:+31-30-285-7100; fax:+31-30-285-7111 Air Products pic, Hersham Place Molesey Road, Walton-on-Thames KT12 4RZ, UK; tel: +44-1932-249-273; fax: +44-1932-249-786 Airex AG Speciality Foams, Anglo-Swiss Aluminium Co Ltd, Mander House, Mander Centre, Wolverhampton WVl 3ND, UK; tel: +44-902-310610; fax:+44-902-29160. Airshrink Europe Ltd, Baird Court, Park Farm Industrial Estate, Wellingborough, Northamptonshire NN8 60J, UK; tel: +44-933-402977; fax: +44-933402144. Akcros Chemicals (Asia-Pacific) Ltd, 7500A Beach Road, Z 15-309 The Plaza, Singapore 199591; tel: +65-292-1966; fax: +65-292-9665 Akcros Chemicals America, 500 Jersey Avenue, PO Box 638, Nev^ Brunswick, NJ 0 8 9 0 3 , USA; tel: +1-908-247-2202; fax: +1-908-247-2287 Akcros Chemicals GmbH & Co KG, Kreuzauer Strafie 46, Postfach 100 146, D-52301Duren, Germany; tel:+49-2421-59502; fax:+49-2421-595191 Akcros Chemicals Ltd, PO Box 1, Eccles, Manchester M30 OBH, UK; tel: +44161-789-7300; fax:+44-161-788-7886 Akro-Plastik GmbH, Industriegebiet Scheid, D-56651 Niederzissen Postfach 67, Germany; tel: +49-2636-97-42-0; fax: +49-2636-97-42-31 Akzo Coatings Inc, 1696 Maxwell Street, Troy, MI 48084, USA; tel: +1-313649-3266; fax:+1-313-649-5256. Akzo Colour & Additive Concentrates, 2 rue de Tlndustrie, 5330 Assesse, Belgium; tel:+32-83-655021; fax:+32-83-656005 Akzo Nobel Casco Products Division Akzo Nobel NV, Velperweg 76, PO Box 9300, 6800 SB Arnhem, The Netherlands; tel: +31-26-366-4343; fax: +31-26-366-4940 Akzo Nobel Chemicals BV, Stationsplein 4, NL-3818 Amersfoort, The Netherlands; tel: +31-33-467-6767; fax: +31-33-467-6100


329

Akzo Nobel Faser AG, Accurel Systems, D-63 784 Oldenburg, Germany; tel: +496022-81-478; fax:+49-6022-81-823 Akzo Nobel NV, Velperweg 76, PO Box 9300, 6800 SB Arnhem, The Netherlands; tel:+31-26-366-4343; fax:+31-26-366-4940 Akzo-Nobel Polymer Chemicals, PO Box 247, 3800 AE Amersfoort, The Netherlands; tel:+31-33-467-767; fax:+31-33-467-6151 Albemarle Corp, 451 Florida Street, Baton Rouge, LA 70801, USA; tel: +1-504388-7040; fax: +1-504-388-7686 Albright & Wilson UK Ltd, Flame Retardants Plastics, PO Box 3,210-222 Hagley Road West, Oldbury, B68 ONN, UK; tel: +44-121-420-5312; fax: +44121-420-5111 Alcan Chemicals Europe, Chalfont Park, Gerrards Cross SL9 OQB, UK; tel: +441592-411-000; fax:+44-1753-233-444 Alcan Metal Centres, Birmingham New Road, Tipton DY4 9AG, UK; tel: +441902-880444; fax: +44-1902-880404 Alchemic Ltd, Brookhampton Lane, Kineton CV35 OJA, UK; tel: +44-1926-641600; fax: +44-1926-641-698 Allied Colloids Ltd, PO Box 38, Cleckheaton Rd, Low Moor, Bradford, West Yorkshire BD12 OJZ, UK; fax: +44-12 74-606499 AlliedSignal Europe NV, Performance Additives, Haasrode Research Park, B-3001 Heverlee, Belgium; tel: +32-16-391-210; fax: +32-16-391 371 AlliedSignal Inc, 101 Columbia Road, Morristown, NJ 07962-2245, USA; tel: + l - 2 0 1 455 2000; fax: +1-201-455-2288 AlliedSignal Inc, Engineered Materials, PO Box 1087, Morristown, NJ 079621087, USA; tel: +1-201-455-2000 AlliedSignal Inc, Fluorine Products, PO Box 108 7, Morristown, NJ 07962-108 7, USA; tel:+1-201-455-6073; fax:+1-201-455-2586 AlliedSignal Inc, High Performance Fibers, PO Box 3 1 , Petersburg, VA 23804, USA; tel: +1-804-520-3242 AlliedSignal Plastics, Haasrode Research Park, B-3001 Heverlee, Belgium; tel: + 32-16-391-320; fax: +32-16-400-103 Alpha Calcit FuUstoff GmbH & Co, KG, 5000 Koln 50, Postfach 1106, Germany; teh +49-2236-89-14-0; fax: +49-2236-40-644 AlphaGary Corp. (HO), 170 Pioneer Drive, Leominster, MA 0 1 4 5 3 , USA; tel: + 1 978-537-8071; fax:+1-978-840-0015 AmeriBrom Inc, 52 Vanderbilt Ave, New York, NY 10017, USA; tel: +1-212286-4000; fax: +1-212-286-4475 American Cyanamid Co, 1 Cyanamid Plaza, Wayne, NJ 07470, USA; tel: + 1-201-831-4619; fax:+1-201-831-2813 American Materials and Technologies (AMT), Los Angeles, Paul Pendorf; tel:+1-310-841-5200; fax:+1-310-837-2845 Americhem Inc, 225 Broadway E, Cuyahoga Falls, OH 4 4 2 2 1 , USA; tel: +1-216929-4213, fax+1-216 929 4144 Americhem Inc, Cawdor Street, Eccles, Manchester M30 OOF, UK; tel: +44-161789-7832;fax:+44-161-787-7832

330


Amherst Process Instruments (Europe) Ltd, Mill Street, Tewkesbury GL20 5SB, UK; tel: +44-1684-291966; fax: +44-1684-293567 Amoco Chemical (Europe) SA, 15 Rue Rothschild, CH-1211 Geneva 2 1 , Switzerland; tel:+41-22-715-0701; fax:+41-22-738-8037 Amoco Chemical Belgium NV, Amocolaan 2, B-2440 Geel, Belgium; tel: +3214-86-43-45; fax: +32-14-86-73-72. Amoco Chemicals, Mail Code 7802, 200 East Randolph Drive, Chicago, IL 60601-7125, USA; tel:+1-312-856-3092; fax:+1-312-856-4151 Amoco Polymers Business Group, 4500 McGinnis Ferry Road, Alpharetta, GA 30205-2203, USA; tel: +1-770-772-8200; fax: +1-404-772-8547 Ampacet Corp, 660 White Plains Rd, Tarrytown, NY 10591, USA; tel: +1-914631-6600; fax:+1-914-631-7278 Ampacet Europe SA, Rued'Ampacet 1, Messancy B-6780, Belgium; tel: +32-6338-13-00;fax:+32-63-38-13-93 Ampacet Europe SA, Rue des Scillas 45, L-2529 Howald, Luxembourg; tel:+352-29-20-99-1; fax:+352-29-20-99-595 Amspec Chemical Corporation, Foot of Water Street, Gloucester City, NJ 08030, USA; tel: +1-609-456-3930; fax: +1-609-456-6704 Andersons, PO Box 119, Maumee, OH 43537, USA; tel: +1-419-891-6545; fax:+1-419-891-6539 Angus Chemical Co, 1500 E Lake Cook Rd, Buffalo Grove, IL 60089, USA; tel:+1-708-215-8600; fax:+1-708-215-8626 Anzon Inc, 2545 Aramingo Ave, Philadelphia, PA 19125, USA; tel: +1-215427-3000; fax:+1-215-427-6955 Anzon Limited, Cookson House, Willington Quay, Wallsend, Tyne and Wear NE26 6UQ, UK; tel:+44-191-262-2211, fax+44-191 263 4491 AP & T Ltd, Unit 11a, Talisman Business Centre, Bicester 0X6 OJX, UK API Spa, Via Dante Alighieri 27, 36065 Mussolente (Vi) Italy; tel: +39-424579-711; fax:+39-424-579-800 API SpA, Via Dante Alighieri 27,1-36065 Mussolente (Vi), Italy; tel: +39-424579-511;fax:+39-424-579-800 APV Baker Ltd, Industrial Extruder Division, Speedwell Road, Parkhouse East, Newcastle-under-Lyme ST5 7RG, UK; tel: +44-782-565656; fax: +44782-565800. Arco Chemical Inc, 3801 West Chester Pike, Newtown Square, PA 190732387,USA;tel:+1-215-359-2000; fax:+1-215-359-2722 Argus Chemical Co, 520 Madison Avenue, New York, NY 10022, USA; tel: + 1 212-605-3600 Aristech Chemical Corporation, PO Box 2219, 600 Grant St, Pittsburgh, PA 15219, USA; tel: +1-412-433-7800; fax: +1-412-433-7721 Asahi Chemical Industry Co Ltd, Hibiyamitsui Building, 1-1-2, Yaraku-cho, Chiyoda-ku, Tokyo 100, Japan; teh +81-3-3507-2730; fax: +81-3-35072005 Asahi Denka Kogyo KK, Furukawa Building 3-14, Nihonbashi-Muromachi 2-chome,Chuo-ku, Tokyo 103, Japan; tel:+81-3-5255-9017; fax:+81-33270-2463


331

Ashland Chemical Co, Box 2219, Columbus, OH 43216, USA; tel: +1-614-8894191;fax:+l-614-889-3735 Ashland Chemical Co, Composite Polymers Division, 5200 Blazer Parkway, Dublin, OH 43017, USA; tel: +1-614-790-3445; fax: +1-614-790-3503 Ashland Chemical Inc, PO Box 2219, Columbus, OH 43216, USA; tel: +1-614889-3333; fax:+1-614-889-3503 Ashley Polymers Inc, 5114 First Hamilton Parkway, Brooklyn, NY 11219, USA; tel:+l-718-851-8111;fax:+1-718-972-3256 ASM International, Materials Park, OH 44073-0002, USA; tel: +1-216-3385151; fax:+1-216-338-4634 Aspanger Geschaftsbereich, Jungbunzlauer GmbH, A-2870 Aspang, Postfach 32, Austria; tel:+43-2642-52355; fax:+43-2642-52673 Astab, c/o Croxton & Garry Ltd, Curtis Road, Dorking RH4 IXA, UK; tel: +441306-886-688; fax:+44-1306-887-780 Aston Industries Ltd, 38 Nine Mile Point Ind. Estate, Crosskeys NPl 7HZ, UK; tel: +44-1495-200-666; fax: +44-1495-200-616 Astor Wax Corp, 200 Piedmont Court, Doraville GA 30340, USA; tel: +1-404448-8083 Asiia Products SA, Ctra Sangroniz 20, E-48150 Soldica (Bilbao), Spain; tel: +344-453-16-50; fax: +34-4-453-35-66 Asua Products, Ctra. Sangroniz 18-20, 4 8 1 5 0 Sondica (Vizcaya), Spain; tel: +34-9-4453-5206; fax: +34-9-4453-3566 ATEM, Via Modena, Angolo Piazza Milano, 24040 Zingonia Ciserano, Italy; tel:+39-35-883255;fax:+39-35-885131 Atlanta, GA 30339, USA; tel:+1-404-951-5700 Atlas SETS BV, BaumstraSe 39, D-47198 Duisburg, Germany; tel: +49-2066560-34; fax: +49-2066-106-19 Avon Rubber pic, Bradford-on-Avon, Wiltshire, UK; tel: +44-1225-861-100; fax:+44-1225-861-199 Axel Plastics Research Laboratories Inc, Box 77 0855, Woodside, NY 11377, USA; tel: +1-718-672-8300; fax: +1-718-565-7447 Axon AB Plastics Machinery, S-265 39 Astorp, Sweden; tel: +46-42-570-80; fax:+46-42-541-52

B BA Chemicals Ltd, Chalfont Park, Gerrards Cross, Bucks SL9 OQB, UK; tel: +441735-887373, fax+44-1753 889602 Barco NV Automation, Kennedypark 35, 8500 Kortrijk, Belgium Barlocher GmbH, RiesstraKe 16, D-80992 Munchen, Germany; tel: +49-89-1437-30,fax+49-89 14 37 33 12 Barlocher USA, West Davis St, PO Box 545, Dover, OH 44622, USA; tel: +1-216364-4000; fax: +1-216-343-7025 Barmag AG, Leverkuser StraEe 65, D-42897 Remscheid, Germany; tel: + 4 9 - 2 1 9 1 - 6 - 7 0 , f a x + 4 9 - 2 1 9 1 6 7 1 7 38

332


BASF AG, 67056 Ludwigshafen, Germany; tel: +49-621-600; fax: + 4 9 - 6 2 1 602-0129 BASF Corporation, Colorants and Additives for Plastics, 3000 Continental Drive North Mount Olive, NJ 07828, USA; tel:+1-201-426-2600 Battenfeld Gloenco Extrusion Systems, Berry Hill Industrial Estate, Droitwich, Worcs.WR9 9RB, UK; tel:+44-1905-775611, fax+44-1905-776716 Battenfeld Holding GmbH, Scherl 10, Postfach 1164/65, D-5882 Meinerzhagen, Germany; tel: +49-2354-720; fax: +49-2354-72565 Baxenden Chemicals Ltd, Applied Chemicals Division, Union Lane, Droitwich WR9 9BB, UK; tel: +44-1905-794795; fax: +44-1905-794002 Baxenden Chemicals Ltd, Speciality Chemicals Division, Paragon Works, BaxendenBB5 2SL, UK; tel:+44-1254 872278; fax:+44-1254 8 7 1 2 4 7 Bayer AG, Bayerwerk, D-51368 Leverkusen, Germany; tel: +49-214-30-1, fax +49-214 30-7407 Bayer AG, D-51368 Leverkusen, Germany; tel: +49-214-30-1; fax: +49-21430-8923 Bayer Corp, 100 Bayer Road, Pittsburgh, PA 15205-9741, USA; tel: +1-412777-2000 BayerLtd,Tokyo,Japan; tel:+81-3-3280-9785; fax:+81-3-3280-9789. BBU, Bleiberger Bergwerks Union AG, RadetzkystraEe 2, Postfach 95, A-9010 Klagenfurt, Austria; tel: +43-42-22-555-25 Bekaert NV, SA, Bekaert straat 2, B-8550 Zwevegem, Belgium; tel: +32-56230511; fax:+32-56-230585 Berga Kunststoffproduktion, mbH & Co KG, Thyssen Strafie 19-21, D-1000 Berlin 51, Germany; tel: +49-330-414-3030; fax: +49-330-41440-95 Hermann Berstorff Maschinebau GmbH, Karen Scheffel, Hannover, Germany; tel:+49-511-57-02-397;fax:+49-511-56-19-16 BI Chemicals Inc Henley Division, 50 Chestnut Ridge Road, Montvale, NJ 07645, USA; tel: +1-201-307-0422; fax: +1-201-301-0424 BICC Compounds, BICC Cables Ltd, Leigh, Lancashire WN7 4HB, UK Biesterfeld Plastic GmbH, FerdinandstraKe 4 1 , D-20095 Hamburg, Germany; tel: +49-40-3-20-08-0; fax: +49-40-3-20-08-442 Bio-Tek Kontron Instruments Ltd, 8 Marlin House, Croxley Business Park, Watford, WD18YA, UK; tel:+44-1923-691300; fax:+44-1923-691301 BIP Chemicals Ltd, PO Box 6 Popes Lane, Oldbury, Warley, W Midlands B69 4PD, UK; tel:+44-121-551-1551; fax:+44-121-552-4267 Blackfriars Ltd, 5 Roman Way, Market Harborough, LE 16 7P0, UK; tel: +441858-462249; fax: +44-1858-464755 Blancs Mineraux de Paris (BMP), 40 rue des Vignobles, F-78402 Chatou Cedex, France; tel: +33-1-39-52-32-63; fax: +33-1-30-71-46-83 BMBiraghi SpA, ViaErcolano 11,1-20052 Monza, Italy; tel: +39-83-31-31; fax: + 39-2-84-09-15 BOC Gases, The Priestley Centre, Surrey Research Park, Guildford GU2 5XY, UK; tel:+44-1483-244-116; fax:+44-1483-244-658 Bock, Otto, Kunststoff GmbH & Co, IndustriestraEe Postfach 12 60, D-3408 Duderstadt, Germany; tel:+49-55-27-82-1; fax:+49-55-27-823-80


333

Boehringer Ingelheim KG, Geschaftsgebeit Chemikalien, D-55216 Ingelheim, Germany; tel:+49-6132-77-38-73; fax:+49-6132-77-46-17 Bohlin Instruments Ltd, Unit 6 The Corinium Centre, Cirencester GL7 lYJ, UK; tel:+44-1285-644407; fax:+44-1285-644314 Bollore Technologies, Industrial Division, BP 29111 Scaer, France; tel: +33-9859-4038 Boy Ltd, 60-70 Tanners Drive, Blakelands, Milton Keynes MK14 5BP, UK; tel: +44-908-613916; fax: +44-908-216401 Brabender Instruments Inc, 50 East Wesley Street, South Hackensack, NJ 07606, USA; teh +1-201-343-8425; fax: +1-201-343-0608 Brabender Technologic KG, KulturstraBe 55-73, PO Box 35 01 38, D-47032 Duisburg, Germany; tel: +49-203-9984-0; fax: +49-203-9984-164 Brampton Engineering Inc, 8031 Dixie Road, Brampton, Ontario, Canada L6T 3Vl;teL+1-905-793-3000; fax:+1-905-793-1753 Branco Industria e Comercio Ltda, Rua Manoel Pinto de Carvalho 229, CEP 02712-120 Sao Paulo SP, Brasil; tel: +55-11-265-8666; fax: + 5 5 - 1 1 872-3735 British Technology Group Ltd, 101 Newington Causeway, London SEl 6BU, UK; tel:+44-171-403-6666; fax:+44-171-403-7586 Britton's Plastics Ltd, Westwood Road, Witton, Birmingham B6 7JE, UK; tel:+44-21-327-0436; fax:+44-21-322-2285 Brockhues AG, D-65396 Walluf, Muhlstrafie 118, Germany; tel: +49-6123-797-403; fax: +49-6123-797-418 Bronkhorst High-Tech BV, Nijverheidsstraat lA, 7261 AK Ruurlo, The Netherlands; tel:+31-573-458800; fax:+31-573-458808 Brookhouse Patterns Ltd, India Mill, Darwen, BB3 IAD, UK; tel:+44-1254 706000 Brown Machine Divn, John Brown Plastics Machinery Ltd, 681 Mitcham Road, Croydon, CR9 3AP, UK; tel: +44-181-684-9082; fax: +44-181-684-9070 Brush Wellman Ltd, Units 4&5, Ely Road, Theale Commercial Estate, Reading RG7 4BQ, UK; tel: +44-734-303733; fax: +44-734-303635 BTG British Technology Group Ltd, 101 Newington Causeway, London SEl 6BU,UK;teL+44-171-403-6666;fax:+44-171-403-7586 BTR Fluoroline, BTR Silvertown Ltd, Horninglow Road, Burton on Trent, Staffs DE13 0SN,UK;teL+44-1283-510510; fax:+44-1283-510113 Buhler Kunststoffe Farben u Additive GmbH, Ritzenschattenhalb 1, D-87480 Weitnau, Germany; tel: +49-8375-920-10; fax: +49-8375-920-130 Burgess Pigments Inc, PO Box 349, Sandersville, GA 31082, USA; tel: +1-912552-2544; fax:+1-912-552-1772 Bush Boake Allen, Terpene Products, Dans Road, Widnes WAS ORE, UK; tel:+44-151-423-3131; fax:+44-151-424-3268 Busing & Fasch GmbH & Co, Abt. Kunststoffe, Cloppenburger StraEe 13 8-140 Buss AG, Basel, CH-4133 Pratteln 1, HohenrainstraEe 10, Switzerland; tel: + 4 1 61-8256-111, fax+41-61-8256-699 Byk-Chemie GmbH, AbelstraSe 14, Postfach 10 02 45, D-46483 Wesel, Germany; tel: +49-281-6-70-0; fax: +49-281-6-82-45

334


Byk-Chemie USA, 524 South Cherry St, PO Box 5670 Wallingford, CT 06492 USA; tel: +1-203-254-2086; fax: +1-203-284-9158

C Cabot Corporation, Special Blacks Division, 157 Concord Rd, Billerica, MA 0 1 8 2 1 , USA; tel: +1-508-670-7042 Cabot Plastics International, Interleuvenlaan 5, 3001 Leuven, Belgium; tel:+32-16-3901-ll;fax:+32-16-4012-53 Cabot Plastics International, rue E Vandervelde 131, B-4431 Ans/Loncin, Belgium; tel:+32-41-46-82-11; fax:+32-41-46-54-99 Cairn Chemicals Ltd, Cairn House, Elgiva Lane, Chesham HP5 2JD, UK; tel: +441494-786-066; fax: +44-1494-791-816 Campine America Inc, 3676 Davis Road, PO Box 526, Dover, OH 44622, USA; tel:+l-216-364-8533;fax:+1-216-364-1579 CEI-Europe, PO Box 910, S-612 2 5 Finspong, Sweden; tel: +46-122-17570; fax: +46-122-14347 Celanese GmbH, Lurgiallee 14, D-60439 Frankfurt, Germany; tel: +49-69-30582319;fax:+49-69-31-7295 CEM, 3100 Smith Farm Road, PO Box 200, Matthews, NC 28106-0200, USA; tel:+l-704-821-3331;fax:+1-704-821-7894 Cerdec Corporation Drakenfeld Products, West Wylie Avenue, PO Box 519, Washington PA 15301, USA; tel: +1-412-223-5900; fax: +1-412-2283170 Certainteed Corporation - FRD, PO Box 860, Valley Forge, PA 19482, USA; tel:+1-215-341-7770; fax:+1-215-293-1765 CFB pic, CFB House, 8-10 Malew Street, Castletown, Isle of Man IM9 lAB, UK; tel:+44-1624-825472; fax:+44-1624-825660 Chapman and Hall, 2-6 Boundary Row, London SEl 8HN, UK; tel: +44-71-5229966; fax: +44-71-522-9623. Chavanoz Industrie, BP 56, 38232 Pont de Cheruy Cedex, France; tel: +33-47246-7900; fax: +33-4-7202-3887 Chemax Inc, Box 6067 Greenville, SC 29606, USA; tel: +1-803-277-7000; fax: 1-803-277-7807 Chemiehandel SE AG, PO Box, CH-8834 Schindellegi, Switzerland; tel: +41-1785-0949; fax: +41-1-785-0143 Chemische Werke Lowi GmbH, Teplitzer Strafie, Postfach 16 60, D-8264 Waldkraiburg, Germany; tel: +49-86-38-4011; fax: 49-86-819-42 Chemoxy International pic, All Saints Refinery, Cargo Fleet Road, Middlesbrough TS3 6AF, UK; tel: +44-642-248555; fax: +44-642-244340 Chemson GmbH, Trakehner Strage 3, D-60487 Frankfurt/Main, Germany; tel: +49-69-7165-0; fax: +49-69-7165-2236 Chemson Ltd, Northumberland Dock Rd, Wallsend NE28 OPB, UK; tel: +44-191258-5892; fax: +44-191-296-1466


335

Chemson Polymer-Additive Gesellschaft mbH, Gailitz 195, A-9601 Arnoldstein, Austria; tel: +43-4255-2226; fax: +43-4255-2435 Chesterfield S41 9QB, UK; tel: +44-1246-260-222; fax: +44-1246-455-420 Chevron Chemical Co, Olefins and Derivatives Division, PO Box 3766, Houston, TX 77253, USA; tel: +1-713-754-2000 ChinghallLtd, Ward Road, Bletchley, MKl IJA, UK; tel: +44-1908-76227 Chromatics Inc, USA; tel; +1-203 743 6868; fax: +1-203-743-1102 Chronos Richardson Ltd, Arnside Road, Bestwood, Nottingham NG5 5HD, UK; tel:+44-115-9835-1351; fax:+44-115-960-6941 Chrostiki, PO Box 22, 194 00 Koropi, Greece; tel: +30-1-6624-692; fax: 30-16623-873 Chuo Kagaku Co Ltd, 3-5-1, Miyagi, KonosuCity, Saitana Prefecture 365, Japan; teL+81-485-42-8631;fax:+81-485-43-3258 Ciba Additive GmbH, PO Box 1640, D-68619 Lampertheim, Germany; tel: +496206-5020; fax:+49-6206-5021-368 Ciba Additives, Hulley Road, Macclesfield SKIO 2NX, UK; tel: +44-1625665000; fax: +44-1625-502-674 Ciba Specialty Chemicals Corp, 540 White Plains Road, PO Box 2005, Tarrytown, NY 10591-9005, USA; teh +1-914-785-2000 Ciba Specialty Chemicals Corp, Pigments Division, 205 South James Street, Newport, DE 19804-2490, USA; tel: +1-302-633-2000 Ciba Specialty Chemicals, PO Box, CH-4002 Basel, Switzerland; tel: +41-61696-3478; fax: +41-61-696-3019 Ciba-Geigy (Japan) Ltd, 10-66 Miyuki-cho, Takarazuka-shi, Hyogo 665, Japan; tel/fax:+81-797-74-2472 Ciba-Geigy Corporation, Chemicals Division, 410 Swing Road, Greensborough, NC 27409-2080, USA; tel: +1-919-632-6000; fax: +1-919-632-7008 Cincinnati Milacron Austria, Laxenburger StraSe 246, A-1239 Wien, Austria; tel: +43-1-61006-267; fax: +43-1-61006-288 Cincinnati Milacron UK Ltd, Plastics Machinery Division, PO Box 505, Kingsbury Road, Birmingham B24 OOU, UK; tel: +44-21-351-5719; fax: +44-21-313-1966 Cincinnati Milacron, Plastics Machinery Division, 4165 Halfacre Road, Batavia, OH45103,USA;tel:+1-513-536-2000; fax:+1-513-536-2552 Cinpres Ltd, Apollo, Lichfield Road Industrial Estate, Tamworth B79 9TA, UK; tel:+44-827-55559; fax:+44-827-53558 CJC Napier Ltd, Unit 3 7, Enterprise City, Green Lane, Spennymoor DLl 6 6JF, UK; t e h + 4 4 - 3 8 8 - 4 2 0 7 2 1 ; fax:+44-388-420718 Clariant Corp, 4000 Monroe Road, Charlotte, NC 28205, USA; tel: +1-704-3317029; fax:+1-704-331-7112 Clariant GmbH, Pigments and Additives Division, Am Unisys-Park 1, 65843 Sulzbach, Germany; teh+49-6196-757-8130; fax:+49-6196-757-8862 Clariant International, RothausstraEe 6 1 , CH-4132 Muttenz 1, Switzerland; tel: +41-61-469-6969; fax: +41-61-469-6999 Clariant Masterbatches Division, Ave de Bpie, BP 149, F-68331, Huningue, France; tel: +33-3-8989-6000; fax: +33-3-8989-6290

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Climax Molybdenum Co, 2275 Swallow Hill Road Building 900, Pittsburgh, PA 15220-1672,USA;tel:+1-412-279-4200; fax:+1-412-279-4710 Coatex, 35 rue Ampere, ZILyonNord, F-6972 7, Genay Cedex, France; tel: +3372-08-2000; fax: +33-72-08-2040 COIM SpA, 1-20019 Settimo Milanese (MI), Via A Manzoni 28, Italy; tel: +39-233505-1; fax: +39-2-33505-249 Colloids Ltd, Dennis Road, Widnes WA8 OSL, UK; tel: +44-151-424-7424; fax: +44-151-495-1715 Color System SpA, Via S. Quasimodo 9, 1-20025 Legnano (Mi), Italy; tel: +39331-577-607; fax:+39-331-464-248 Colorant Chromatics AG, Switzerland; tel: +41-41-741-0101; fax: +41-41741-0102 Colorant GmbH, Justus-Staudt-StraKe 1, D-6250 Limburg-Offheim, Germany; tel:+49-6431-53391 Color-Chem International Corp, 8601 Dunwoody Place, Bldg 334, Atlanta, GA 30350, USA; tel: +1-770-993-5500; fax: +1-770-993-4780 Colores Hispania, Josep Pla 149, Barcelona 08019, Spain; tel: 34-3-307-1350; fax:+34-3-303-2505 Colores y Compuestos Plasticos SA, C/Fedanci, 8 al 10 bajos 2^, Pare Empresarial ColorMatrix Europe Ltd, Unit 9 Unity Grove, Knowsley Industrial Park South, Knowsley L34 9GT, UK; tel: +44-151-548-3100; fax: +44-151-5483800 Color-Plastics-Chemie, Postfach 12 05 10, D-5630 Remscheid 11, Germany; tel:+49-2191-530-059; fax:+49-2191-516-95 Color-Service GmbH, Offenbacher Landstrafie 107-109, D-63512 Hainburg/ Hess, Germany; tel: +49-6182-4034-37; fax: +49-6182-668-86 Colortech Inc, 5712 Commerce Boulevard, Morristown, TN 37814, USA; tel: + 1-905-792-0333; fax:+1-905-792-8118 Colortronic (UK) Ltd, Matilda House, Carrwood Road, Chesterfield Industrial Estate Columbian Chemicals Co, 1600 Parkwood Circle, Suite 400 Comiel SpA, Via Bessarione 1, 1-20139 Milano, Italy; tel: +39-2569-341; fax: + 39-2569-181 Compounding Technology AG, Baumgartenweg 4, CH-4106 Therwil (Basel), Switzerland; tel: +41-61-722-0526; fax: +41-661-722-0529 Conair Europe Ltd, Riverside Way, Uxbridge UBS 2YF, UK; tel: +44-895850500; fax: +44-895-850555 Condux, Maschinenbau GmbH & Co, Rodenbacher Chaussee 1, D-6450 Hanau 11, Germany; tel:+49-6181-50601; fax:+49-6181-571270 Constab Polymer-Chemie GmbH & Co, Mohnetal 16 Postfach 112 7, D-59602 Ruthen/Mohne, Germany; tel: +49-2952-8190; fax: +49-2952-3140 Continent Machinery Industries, No 5 Ching Pu Tsuen, Liou Chia Hsiang, Tainan, Taiwan; tel: +886-6-698-6666; fax: +886-6-698-6238 Cookson Pigments Inc, 56 Vanderpool Street, Newark, NJ 07114, USA; tel: + 1 201-242-1800; fax: +1-201-242-7274 Cookson Plastics Ltd, Uttoxeter Road, Meir, Stoke-on-Trent ST3 7YA, UK; tel:+44-1782-599-111; fax:+44-1782-312-409


337

Cookson Specialty Additives, 1000 Wayside Road, Cleveland, OH 44110, USA; tel:+1-216-531-6010; fax:+1-216-486-6638 Corduplast GmbH, Postfach 1227, D-4417 Althenberge, Germany; tel: +492505-2186 Costenoble GmbH, Postfach 5205, D-6236 Eschborn, Germany; tel: +49-6196440-20; fax: +49-6196-481-283 CPM GmbH, Werner-von-Siemens-StraEe 19, D-49124 Georgsmarienhutte, Germany; tel: +49-5401-82940; fax: +49-5401-8294-29 Cp-Polymer-Technik, Berliner StraKe 3-5, D-2863 Ritterhude, Germany; tel: +49-4292-1034 Cristal, National Titanium Dioxide Co Ltd, PO Box 13586, Jeddah 21414, KingdomofSaudiArabia; tel:+966-2-651-9883; fax:+966-2-651-8757 Croda Universal Inc, 4014 Walnut Pond Drive, Houston, TX 77059, USA; tel: +1-713-282-0022; fax: +1-713-282-0024 Croda Universal, Division of Croda International pic, Cowick Hall, Snaith, Goole DN14 9AA, UK; tel: +44-1405-860551; fax: +44-1405-860205 Crompton & Knowles Corp, PO Box 33188, Charlotte, NC 2 8 2 3 3 , USA; tel: + 1 704-372-5890; fax:+1-704-372-1522 Crowley Chemical Co Inc, 261 Madison Ave, New York, NY 10016, USA; tel: + 1 212-682-1200; fax: 1-212-953-3487 Croxton & Garry Ltd, Curtis Road, Dorking RH4 IXA, UK; tel: +44-1306-886688; fax: +44-1306-887-780 CT Compounding Technology AG, Baumgartenweg 4 Postfach, CH-4106 Therwil (Basel), Switzerland; tel: +41-61-7220-526; fax: +41-61-7220529 C-Tech Corporation, 5-B, 5th Floor, Himgiri 12 77 Hatiskar, Marg, Mumbai 400 025, India; tel: +91-22-422-5939; fax: +91-22-430-9295 Cytec Industries Inc, Five Garret Mountain Plaza, West Paterson, NJ 07424, USA; tel:+1-201-357-3100

D Daicel Chemical Industries, 1, Teppo-cho, Sakai-shi, Osaka 590, Japan; tel: + 8 1 722-27-3111;fax:+81-722-27-3000 Dai-ichi Kogyo Seiyaku Co. Ltd, New Kyoto Center Building, 614 Higashishiokoji-cho, Shimukyo-ku, Kyoto 600, Japan; tel: +81-75-3431181;fax:+81-75-343-1421 Dainippon Ink & Chemicals Inc, 3-7-20, Nihonbashi, Chuo-ku, Tokyo 103, Japan;tel:+81-3-3272-4511;fax:+81-3-3278-8558 Daltex Medical Sciences Inc, 50 Kulick Road, 2nd Floor, Fairfield, NJ 07004, USA; tel: +1-201-227-5066; fax: +1-201-227-6339 Daniel Products Co Inc, 400 Claremont Ave, Jersey City, NJ 07304, USA; tel: + 1 201-432-0800; fax: +1-201-432-0266 Danisco Ingredients, Edwin Rahrsvej 38, Brabrad DK-8220, Denmark; tel: +4589-43-5000; fax: +45-86-25-1077

338


Datacolor International, 6 St Georges Court, Dairyhouse Lane, Altrincham WA14 SUA, UK; tel: +44-161-929-9441; fax: 44-161-929-9059 Davis Standard Asia, Room 1211 Peninsula Centre, 6 7 Mody Road, Tsimshatsui Kowloon, Hong Kong; tel: +852-2-723-1787; fax: +852-2-724-4263 Davis-Standard Compounding Systems, 1 Extrusion Drive, Pawcatuck, CT 06379, USA; tel: +1-203-599-1010; fax: +1-2-3-599-6258 Davis-Standard Europe, Tricorn House, Cainscross Stroud GL5 4LF, UK; tel:+44-1453-765-111; fax:+44-1453-750-819 Davy Process Technology, 68 Hammersmith Road, London W14 8YW, UK; tel: +44-71-603-6633; fax: +44-71-872-8741 DBL International Inc, Nijvelsebaan 9 1 , B-Overijse, Belgium; tel: +32-2-6880782; fax: +32-2-646-4677 DCE Limited, Humberstone Lane, Thurmaston, Leicester LE4 8HP, UK; tel: +44116-269-6161 Dead Sea Bromine Compounds, PO Box 180, beer Sheva 8 4 1 0 1 , Israel; tel:+972-7-297-265; fax:+972-7-280-444 Decillion LLC, c/o Owens Corning World HQ, Fiberglas Tower, Toledo, OH 43659, USA; tel: +1-419-248-8000 Degussa AG, GB Anorganische, Chemieprodukte (AC-KP), D-60287 Frankfurtam-Main, Germany; tel: +49-69-218-01; fax: 49-69-218-3218 Degussa-Hiils AG, WeiSfrauenstraKe 9, D-60287 Frankfurt-am-Main, Germany; tel: +49-69-218-2055; fax: +49-69-218-3743 Deltacolor SA, Delta Tecnic SA, Poligono Industrial Moli de les Planes - c/Rec Moli de les Planes, s/n, 08470 Sant Celoni (Barcelona), Spain; tel: +34-93867-4284; fax: +34-93-867-5229 Denko Kagaku Kogyo Co Ltd, Sanshin Building, 1-4-1, Yuraku-cho, Chiyoda-ku, Tokyo 100, Japan; tel: +81-3-3507-5032; fax: +81-3-3508-2739 Department of Trade and Industry, 1 Victoria Streeet, London SWIH OET, UK; tel:+44-171-215-5000;fax+44-171 215 6740 Desco Industries Inc, 761 Penarth Avenue, Walnut, CA 91789, USA; tel: + 1 909-598-2753; fax: +1-909-595-7028 Diadema Industrias Quimicas Ltda, Av Fagundes de Oliveira 190, Piraporinha Diadema,SP 09950-907, Brazil; tel:+55-11-745-4133; fax:+55-11-7462011 Diversey Ltd, Waston Favell Centre, Northampton NN3 4PD, UK; tel: +44-1604405-311 DJ Enterprises Inc, Box 31366, Cleveland, OH 44131-0366, USA; tel: +1-216524-3879 Doeflex pic, Holmethorpe Avenue, Redhill, Surrey RHl 2NR, UK; tel: +44-73 7771221;fax:+44-737-772461 Dover Chemical Corp, ICC Industries Inc, 3676 Davis Rd NW, PO Box 40, Dover, OH 44622, USA; tel:+1-216-343-7711; fax:+1-216-364-1579 Dover Chemical Ltd, Amsteldijk 166, NL-1079 LH Amsterdam, The Netherlands Dow Chemical Co, 2040 Dow Center, Midland, MI 46874, USA; tel: +1-517636-2303;fax:+1-517-638-9752


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Dow Corning Europe, Rue General de Gaulle 62, B-1310 La Hulpe, Belgium; tel: 32-2-655-2111; fax:+32-2-655-2001 Dow Corning GmbH, SchoSburgstraBe 24, D-65201 Wiesbaden, Germany; tel:+49-611-928-630; fax:+49-611-246-28 Dow Europe SA, BachtobelstraSe 3, PO Box, CH-8810 Horgen, Switzerland; tel:+41-l-728-2111;fax:+41-1-728-2935 Dow Information Centre, Schurenbergweg 5, 1105 AP Amsterdam-Zuidoost, TheNetherlands; tel:+31-2069-16268 Dow Plastics, 26200 American Drive, Southfield, MI 48034, USA; tel: +1-313358-1300; fax:+1-313-948-1708 DSM NV, PO Box 6500, 6401 JH Heerlen, The Netherlands; tel: +31-45-5782422; fax: +31-45-574-0680 DSM Performance Polymers BV, PO Box 43, 6130 AA Sittard, The Netherlands; tel:+31-46-477-3965; fax:+31-46-477-0070 DSM Resins, PO Box 615, Zwolle NL 8000, The Netherlands; tel: +31-38-284911;fax:+31-38-284-284 Du Pont (UK) Ltd, Maylands Avenue, Hemel Hempstead HP2 7DP, UK; tel: +44442-218500; fax: +44-442-249463. DuPont Asia Pacific Ltd, 1122 New World Office Building, East Wing, Salisbury Road, Kowloon, Hong Kong; tel: +852-734-5345; fax: +852-724-4458 DuPont de Nemours & Co, 1007 Market Street, Wilmington, DE 19898, USA; tel: +1-302-774-1000; fax: +1-302-774-7321 DuPont de Nemours (Luxembourg) SA, Specialty Chemicals, L-2984 LuxembourgContern, Luxembourg; tel: +352-3666-5646; fax: +352-3666-5015 DuPont de Nemours International SA, Chemin du Pavilion 2, PO Box 50, CH-1218 Le Grand-Saconnex, Switzerland; tel: +41-22-717-5111; fax:+41-22-717-5109 DuPont Dow Elastomers, CH-1218 Le Grand-Saconnex, Switzerland; tel: + 4 1 22-717-5111; fax:+41-22-717-5109 DuPont Far East Inc, Kowa Building No 2, Akasaka 1-chome, Minato-ku, Tokyo 107,Japan;teL+81-585-5511 DuPont Japan Ltd, Shin Nikko Building, Du Pont Tower, 2-10-1, Toranomon, Minato-ku, Tokyo 105, Japan; tel: +81-3-3585-5511; fax: +81-3-32248992. Dynamit Nobel AG, Sparte Chemikalien, D-5210 Troisdorf, Germany; tel: +4922-41-850; fax: 49-22-41-8527-93 Dyneon GmbH, Hammfelddamm 11, D-41460 Neuss, Germany; tel: + 4 9 - 2 1 3 1 14-2727; fax:+49-2131-14-3857 Dyneon LLC, 6744 33rd Street North, Oakdale, MN 55128, USA; tel: +1-612737-6700; fax: +1-612-737-7686 Dyno Industrier AS, PO Box 779, Sentrum N-0106 Oslo, Norway; tel: +47-2231-7000; fax:+47-22-3178-56. Gebr. Dorfner GmbH & Co, D-92242 Hirschau, Germany; tel: 49-9622-820; fax: +49-9622-8269 Georg Deifel KG, Mainberger StraBe 10, D-8720 Schweinfurth, Germany; tel:+49-9721-1774; fax:+49-9721-185-099

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E C H Erbsloh, Dusseldorfer StraEe 103, D-47809 Krefeld, Germany; tel: +492151-52500; fax:+49-2151-525-152 C H Erbsloh, KaistraBe 5 Postfach 29 26, D-2000 Hamburg 11, Germany; tel:+49-211-390-0161; fax:+49-211-390-0121 Eastman Chemical Co, 1540 Broadway, New York, NY 10036, USA; tel: + 1 212-782-5200; fax:+1-212-782-5212. Eastman Chemical Co, Polymer Additives and Specialty Monomers Business Unit, POBox 4 3 1 , Kingsport, TN 37662, USA; tel: +1-615-229-2000; fax: + 1-615-224-0648 Eastman Chemical, Europe, Middle East and Africa Ltd, Tobias Asserlaan 5, 2517 KC The Hague, The Netherlands; tel: +31-70-370-1722; fax: + 3 1 70-3 70-1702 ECC International pic, John Keay House, St. Austell PL25 4DJ, UK; tel: +441726-74482; fax:+44-1726-623019 ECC International SA, 2 rue du Canal, B-4551 Lioxhe, Belgium; tel: + 3 2 - 4 1 7998-ll;fax:+32-41-7982-79 ECC International, 100 Mansell Court East, Suite 300, Roswell, GA 30076, USA; tel: +1-770-594-0660; fax: +1-770-645-3384 ECC Japan Ltd, 10th Central Building, 10-3 Ginza 4-chome, Chuo-ku, Tokyo 104,Japan; tel:+81-3-3456-8250; fax:+81-3-3456-8255 Eckart-Werke GmbH, Kaiserstrage 30, D-90763 Furth, Germany; tel: + 4 9 - 9 1 1 99-78-0; fax:+49-911-78-238 Elan Corp; 174 Post Road West, Westport, CT 06880, USA; tel: +1-203-2227399; fax:+1-203-222-1819 Elastogran GmbH, Postfach 1140 D-49440 Lemforde, Germany; tel: + 4 9 - 5 4 4 3 12-0; fax: +49-5443-12-2100 Elementis pic. One Great Tower Street, London EC3R 5AH, UK; tel: + 4 4 - 1 7 1 711-1400 Elementis Specialties, 400 Claremont Avenue, Jersey City, NJ 07304, USA; tel: + 1-201-432-0800; fax: +1-201-432-0266 Elf Atochem Deutschland GmbH, TersteegenstraBe 28, D-40474 Dusseldorf, Germany; tel:+49-211-4552-304; fax:+49-211-4552-349 Elf Atochem North America, 2000 Market Street, Philadelphia, PA 19103, USA; tel:+1-215-419-7000; fax:+1-215-419-7413 Elf Atochem UK Ltd, Colthrop Way, Thatcham, Newbury RG13 4LW, UK; tel: +44-635-870000; fax: +44-635-870050. Elf Atochem, Cedex 42, 92091 Paris-La-Defense, France; tel: +33-1-49-008018; fax: +33-1-49-00-8050 Ellis & Everard Pic, 119 Guildford St, Chertsey, Surrey KT16 9AL, UK; tel: +441932-566033;fax:+44-1932-560363 EM Industries Inc, 5 Skyline Drive, Hawthorne, NY 10532, USA; tel: +1-914592-4660; fax: +1-914-592-9469 Emerson & Cuming, Composite Materials Inc, 77 Dragon Court, Woburn, MA 01888,USA;tel:+1-617-938-8630; fax:+1-617-933-4318


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EMS-Chemie AG, 7013 Domat/Ems, Switzerland; tel: +41-81-36-7345; fax: +41-81-36-7454 Endex International, 111 Main Street, Box 381, Kingston, IL 60145, USA; tel:+1-815-784-2446; fax:+1-815-784-6012 Endex Polymer Additives Inc, 2198 Ogden Ave, Suite 131, Aurora, IL 60504, USA Engel Vertriebsgesellschaft mbH, A-4311 Schwertberg, Austria; tel: +43-7262620-0; fax: +43-7262-620-308 Engelhard Corp, 101 Wood Ave, Iselin, NJ 08830-0770, USA; tel: +1-908-2055 0 0 0 ; f a x + l - 9 0 8 321 0250 Engelhard Corp, Performance Minerals Group, 101 Wood Ave S. CN 770, Iselin, NJ 08830-0770, USA; tel:+1-908-205-5000; fax:+1-908-205-6711 EniChemPolimerisrl, ViaRossellini 15-17,1-20124, Italy; tel:+39-263-331 EPI (UK) Ltd, European HQ, Chatsworth Technology Park, Chesterfield S41 8XA, UK; tel: +44-1246-261882; fax: +44-1246-261883 EPI Environmetal Products Inc, 103 Longview Drive, Conroe, TX 77301, USA; tel: +1-409-788-2998; fax: +1-409-788-2968 Epolin Inc, 358-364 Adams St, Newark, NJ 07105, USA; tel: +1-201-465-9495; fax:+1-201-465-5353 Esseti Plast Sri, Via IV Novembre 98, 1-21058 Olona (Va), Italy; tel: + 3 9 - 3 3 1 641-159;fax:+39-331-375-182 Ethyl SA Chemicals Group, London Road, Bracknell RG12 2UW, UK; tel: +441344-780-378; fax:+44-1344-773-860 European Vinyls Corporation International SA/NV, Boulevard du Souverain 360, B-1160 Brussels, Belgium; tel: +32-2-674-0967; fax: +32-2-6601181 Europol pic, Fauld Industrial Estate, Tutbury, Burton-on-Trent, Staffs DEI 3 9HR, UK; tel:+44-1283-815-611; fax:+44-1283-813-139 Eurotherm Controls Ltd, Faraday Close, Durrington, West Sussex BNl 3 3PL, UK; tel: +44-1903-268500; fax: +44-1903-265982 EVAL Co of America, 1001 Warrenville Rd, Suite 2 0 1 , Lisle, IL 60532, USA; tel:+1-630-719-4615 EVC International SA/NV, Boulevard du Souverain 360, B-1160 Brussels, Belgium; tel: +32-2-674-0967; fax: +32-2-660-1181 Everlight Chemical industrial Corp, 6 Floor, Chung Ting Bldg, No 77 Sec 2 Tun Hua S Road, Taipei, RC; tel: +886-2-706-6006; fax: +886-2-708 1254 Evode Plastics Ltd, Wanlip Road, Syston, Leicester LE7 8PD, UK; tel: +44-1533696-752; fax:+44-1533-692-960 Exatec GmbH & Co KG, Friedrich-Ebert-StraBe, D-51429 Bergisch Gladbach, Germany; tel:+49-2204-84-2700; fax:+49-2204-84-2705 Exatec LLC, 31220 Oak Creek Drive, Wixom, MI 4 8 3 9 3 , USA Expancel, Box 13000, 850-13 Sundsvall, Sweden; tel: +46-60-1340-00; fax: +46-60-5695-18 Exxon Chemical Europe Inc, Mechelsteenweg 363, B-1950 Kraainem, Belgium; + 32-2-769-3562; fax:+32-2-769-3446

342


Exxon Chemical Europe Inc, Vorstlaan 280, Bid du Souverain, B-1160 Brussels, Belgium; tel:+32-2-674-4111; fax:+32-2-674-4129 Exxon Chemical Europe, Mechelesteenweg 363, B-1950 Kraainem, Belgium; tel:+32-2-769-3111; fax:+32-2-769-3225 Exxon Chemical Ltd, PO Box 122, 4600 Parkway, Fareham, Hampshire P 0 1 5 7AP, UK; tel: +44-489-884406; fax: +44-489-884477 Exxon Corp, PO Box 140369, Irving, TX 75014-0369, USA; tel: +1-972-4441000

F Faerch Plast A/S, PO Box 10 40, DK-7500 Holstebro, Denmark; tel: +45-97425122; fax:+45-97-401476 Fagerdala World Foams AB, S-13900 Vaermdoe, Sweden; tel: +46-766-45200; fax:+46-766-45940 Fahr Bucher GmbH, GewerbestraGe 3 1 , D-78240 Gottmadingen, Postfach 1164, Germany; tel: +49-7731-904-0; fax: +49-7731-904-151 Fairmount Chemical Co Inc, 117 Blanchard Street, Newark, NJ 0 7 1 0 5 , USA; tel:+1-201-344-5790; fax:+1-201-690-5298 Fanuc Ltd, Oshinomura, Minami-Tsurugun, Yamanashi Prefecture 401-05, Japan; tel:+81-555-84-5555; fax:+81-555-84-5512; tx: 3385402 Farrell Corporation, 25 Main Street, Ansonia, CT 0 6 4 0 1 , USA; tel: +1-203-7365500 Faxe Kalk, Frederiksholms Kanal 16, PO Box 2183, DK-1017, Copenhagen K, Denmark; tel:+45-33-13-7500; fax:+45-33-12-7874 FCM Parco Sri, Via Sansovino 243/50, 10151 Turin, Italy; tel: +39-11-9840814;fax:+39-11-984-0114. Ferro Chemicals Group, 1000 Lakeside Ave, Cleveland, OH 44114, USA; tel: + 1 216-641-8580 Ferro Corp, World Headquarters, 1000 Lakeside Avenue, Cleveland, OH 441141183, USA; tel:+1-216-641-8580; fax:+1-216-696-6958 Ferro Plastic Europe, v. Helmenstraat 20, NL-3029 AB Rotterdam; tel: +31-10478-4911; fax:+31-10-477-8202 Ferrofluidics Ltd, Talisman Business Centre, Bicester, Oxford 0X6 OJX, UK; tel: +44-1869-363200; fax: +44-1869-363201 Fibrolux GmbH, Oberlindau 23, D-6000 Frankfurt/Main, Germany; tel: +49-6972-8903; fax: +49-69-724-1212 Filtec Ltd, Constance House, Waterloo Road, Widnes, Cheshire WAS OQR, UK; tel:+44-151-495-1988; fax:+44-151-1407 Fina Chemicals, Rue de Tlndustrie 52, B-1040 Brussels, Belgium; tel: +32-2288-3143; fax: +32-2-288-3322 Karl Finke GmbH & Co KG, Hatzfelder StraBe 174-176, D-42281 Wuppertal, Germany; tel: +49-202-70-9060; fax: +49-202-70-3929 FMC Corporation, Chemical Products Group, 1735 Market Street, Philadelphia, PA 19103, USA; tel:+1-215-299-6000; fax:+1-215-299-5999


343

Foboha GmbH, SchwarzwaldstraSe 4, D-7612 Haslach, Germany; tel: +497832-7980; fax: +49-7832-798-88 Formold Ltd, Ruscombe Park, Ruscombe Lane, Twyford RGIO 9JZ, UK; tel: +44734-340443; fax: +44-734-342160. Forsheda Polymer Engineering Group, Lambourn Court, Abingdon 0X14 lUH, UK; tel:+44-1235-555570; fax:+44-1235-536359 Forward Ultrasonics, l i e Cosgrove Way, Luton LUl IXL, UK; tel: +44-582429335; fax: +44-582-456359. Foster Wheeler Corp, Perryville Corporate Park, Clinton, NJ 08809-4000, USA; tel: +1-908-730-5262; fax: +1-908-730-5315 Foster Wheeler Ltd, Foster Wheeler House, Station Road, Reading, Berkshire RGl ILX, UK; teL +44-734-585211; fax: +44-734-396333. Franklin Industrial Minerals, 612 Tenth Avenue North, Nashville, TN 3 7203, USA; tel:+1-615-259-4222; fax:+1-615-726-2693 Frekote Inc, 164 Folly Mill Road, Seabrook, NH 03874, USA; tel: +1-603-4745541 Frekote Mold Release Products, Dexter Corp, One Dexter Drive, Seabrook, NH 03874-4018, USA; tel:+1-603-474-5541; fax:+1-603-474-5545 Freudenberg Carl, Postfach 180, D-6940 Weinheim, Germany; tel: + 4 9 - 6 2 0 1 801; fax: 49-6201-69300 Frisetta GmbH, Postfach 49, D-7869 Schonau/Schwarzwald, Germany; tel:+49-76-73-10014 Fuji Heavy Industries Ltd, 1-7-2, Nishi-Shinjuku, Shinjuku-ku, Tokyo 160, Japan; tel: +81-3-3347-2024; fax: +81-3-3347-2338

G

Gabriel Chemie GmbH, Industriestrafie 1, A-2352 Gumpoldskirchen, Austria; tel:+43-2252-636-300; fax:+43-2252-636-60 Gabriel-Chemie UK Ltd, Transfesa Road, Paddock Wood TNI2 6UT, UK; tel: +44892-836566; fax: +44-892-836979. Gas Injection Ltd, Kiltearn House, Hospital Street, Nantwich CW5 5RL, UK; tel: +44-270-625678; fax: +44-270-626646. Gaypa Sri, Via Tribollo 6/8, Minticello Conte Otto (Vi), Italy; tel: +39-444-946088; fax: 39-444-946-027 GE Speciality Chemicals, General Electric Plastics BV, Plasticslaan 1, PO Box 117, NL-4600 AC Bergen op Zoom, The Netherlands; tel: +31-164032911;fax:+31-1640-32940 GE Specialty Chemicals, PO Box 1868, 501 Avery Street, Parkersburg, WV 26102-1868, USA; tel: +1-304-424-5411; fax: +1-304-424-5871 GenCorp Polymer Products, 165 S. Cleveland Avenue, Mogadore, OH 44260, USA; tel:+1-216-628-6542; fax:+1-201-515-2468 The Geon Company, One Geon Center, Avon Lake, OH 44012, USA; tel: +1-440930-1000 George Fischer (Great Britain) Ltd, Paradise Way, Walsgrave Triangle, Hinckley Road, Coventry CV2 2SP, UK; tel: +44-203-535535; fax: +44-203-530450

344


Georgia Marble Co, 1201 Roberts Blvd, Bldg 100, Kennesaw, GA 30144-3619, USA; tel:+1-404-421-6500; fax:+1-404-421-6507 Gevetex Texilglas GmbH, Postfach 1160, D-5120 Herogenrath, Germany; tel: +49-2406-810; fax: +49-2406-792-86 GF Axxicon BV, PO Box 3229, NL-5902 RE Venlo, The Netherlands; tel: +31-77820055; fax: +31-77-824465. GFI (UK) Ltd, Marie Place, Brenchley, Tonbridge, UK; tel: +44-1892-724-534 fax:+44-1892-724-4099 Gharda Chemicals Ltd, 48 Hill Road, Bandra (W), Bombay 400 050, India tel: +91-22-642-6852; fax: +91-22-640-4224 Gildemeister (UK) Ltd, Unitool House, Camford Way, Sundon Park, Luton, UK tel:+44-582-570661; fax:+44-582-593700. GlassTech Scandinavia AB, Box 1013, Angelholm 262-21, Sweden; tel: +46431-250-75; fax: +46-431-250-76 Goldmann GmbH & Co KG, Postfach 3405, Bielefeld 1, Germany; tel: +49-5213-5046; fax: +49-5-213-224-52 Th. Goldschmidt AG, Postfach 10 14 6 1 , D-45116 Essen, Germany; tel: +49201-173-2365; fax:+49-201-173-1838 Goldschmidt Chemical Corp, 11 West 17th Street, Suite G3, Costa Mesa, CA 92627, USA; tel: +1-714-650-2161; fax: +1-714-642-9478 Goldschmidt Industrial Chemical Corp, Pitt Metals and Chemicals Divn, 941 Robinson Highway, PO Box 2 79, McDonald, PA 15057-02 79, USA; tel:+l-412-796-1511;fax:+1-412-922-6657 B F Goodrich Chemical, Goerhtzer StralSe 1, D-4040 Neuss, Germany; tel: +4921-01-180-50; fax:+49-21-01-1800 B F Goodrich Specialty Chemicals, 9911 Brecksville Road, Cleveland, OH 4 4 1 4 1 3247, USA; tel:+1-216-447-5000; fax:+1-216-447-5750 Goodyear Chemical, Av des Tropiques, ZA Courtaboef 2, F-91955 Les Ulis Cedex, France; tel: 33-216-796-8295 Goodyear Tire & Rubber Co, Akron, OH 44316, USA; tel: +1-216-796-8295; fax:+1-216-796-3199 Great Lakes Chemical (Deutschland) GmbH, Overather Strafie 50-52, D-51429 Bergisch Gladbach, Germany; tel: +49-2204-954-30; fax: +49-2204-56862 Great Lakes Chemical (Europe) GmbH, JuchstraSe 45, CH-8500 Frauenfeld, Switzerland; tel: +41-52-723-4400; fax: +41-52-723-4499 Great Lakes Chemical (Europe) Ltd, PO Box 44, Oil Sites Road, Ellesmere Port, L65 4GD, UK; tel: +44-151-356-8489; fax: +44-151-356-8490 Great Lakes Chemical Corp, PO Box 2200, West Lafayette, IN 47906, USA; tel:+1-317-497-6100 GretagMacbeth Ltd, Pacific Road, Altrincham WA14 5BJ, UK; tel: +44-161926-9822; fax: +44-161-926-9835 Grinit Plast Sri, 22076 Mozzate (Co), Strada Statale 223, 1126, Italy; tel: +39331-831-625;fax:+39-331-833-731 Gulf Lubricants, Rosehill, New Barn Lane, Cheltenham GL52 3LA, UK; tel: +441242-225588;fax:+44-1242-225507


345

Gusmer Machinery Group Inc, One Gusmer Drive, PO Box 2055, Lakewood, NJ 08701-8055, USA; tel: +1-908-370-9000; fax: +1-908-905-8968 Gusmer-Admiral Inc, 305 West North Street, Akron, OH 4 4 3 0 3 , USA; tel: + 1 330-253-1353; fax:+1-330-253-7715

H G E Habich's Sohne, Postfach 67, D-3512 Reinhardshagen, Germany; tel: +4955-44-1071; fax:+49-55-44-79172 Hager & Kassner GmbH, Postfach 4 49, D-4730 Ahlen 1, Germany; tel: +49-2140-9074; fax:+49-23-82-5151 Hampton Colours Ltd, Toadsmoor Mills, Brimscombe, Stroud GL5 2UH, UK; tel: +44-1453-731-555; fax: +44-1453-731-234 Handy & Harman Automotive Group Inc, Auburn Hills, MI, USA; tel: +1-810377-0700; fax:+1-810-377-2085 Hanna Company - Wilson Color, 161 Dreve de Richelle, 1410 Waterloo, Belgium; tel: +32-2-352-0550; fax: +32-2-353-0566 M A Hanna Company, Suite 36-5000, 200 Public Square, Cleveland, OH 441142304, USA; tel: +1-216-589-4000; fax: +1-216-589-4200 Hanse Chemie GmbH, Charlottenburger StraSe 9, D-21502 Geesthacht, Germany; tel: +49-41-5280-920; fax: +49-41-5279-156 Harcros Chemicals UK Ltd, Lankro House, Silk St PO Box 1, Eccles, Manchester M300BH,UK;tel:+44-161-789-7300; fax:+44-161-787-8313 Hartmann Drukfarben GmbH, Postfach 60 03 49, D-6000 Franfurt/Main, Germany; tel: +49-69-4000-1; fax: +49-69-4000-286 W Hawley & Son Ltd, Colour Works, Duffield, Belper DE56 4FG, UK; tel: +441332-840-294; fax:+44-1332-842-570 Henkel Corp, 11501 Northlake Drive, Cincinnati, OH 45249, USA; tel: +1-513530-7415; fax:+1-513-530-7581 Henkel KGaA, Plastics Technology, D-40191 Dusseldorf, Germany; tel: +49211-7970; fax:+49-211-798-9638 Heraeus Equipment Ltd, Unit 9, Wates Way, Brentwood, Essex CM15 9TB, UK; tel:+44-277-231511;fax:+44-277-261856. Herberts GmbH, Christbusch 25 Postfach 2002 44, D-5600 Wuppertal 2, Germany; tel: +49-202-8941; fax: +49-202-8995-73 Herberts Polymer Powders SA, PO Box 140, CH-1630 Bulle, Switzerland; tel:+41-26-913-5111; fax:+41-26-912-7989 Herbold Granulators UK Ltd, 6 Dewar Court, Astmoor, Runcorn WA7 IPT, UK; tel: +44-928-581309; fax: +44-928-581306 Hettinga Equipment Inc, 2123 North West 111th Street, Des Moines, lA 503253 788, USA; tel:+1-515-270-6900; fax:+1-515-2 70-1333 High Polymer Laboratories, Vishal Bhawan, 95 Nehru Place, New Delhi 110 019, India; tel:+91-11-643-1522; fax:+91-11-647-4350 Hitox Corp. of America, PO Box 2544, Corpus Christi, TX 78403, USA; tel: + 1 512-882-5175; fax:+1-512-882-6948

346


Hoechst AG, Business Unit Additive, Gersthofen Postfach 10 15 67, D-86005 Augsburg 1, Germany; tel: +49-821-4790; fax: +49-821-479-2890 Hoffmann Mineral, Postfach 14 60, D-86619 Neuburg (Donau), Germany; tel: +49-84-31-530; fax: +49-84-31-53-330 Holland Colors America Inc, 1501 Progress Drive, Richmond, IN 47374, USA; tel:+1-317-935-0329; fax:+1-317-966-3376 Holland Colours Apeldoorn BV, Halvemaanweg 1 Postbus 720, 7300 AS Apeldoorn,TheNetherlands; tel:+31-55-366-3143; fax:+31-55-366-2981 Holliday Chemical Holdings pic, Brikby Grange, 85 Birkby Hall Rd, Huddersfield HD2 2XB, UK; tel: +44-1484-828-200; fax: +44-1484-828-230 Holliday Pigments Ltd, Morley Street, Kingston-upon-Hull HU8 8DN, UK; tel:+44-1482-329-875; fax:+44-1482-223-114 Holometrix Inc, 25 Wiggins Avenue, Bedford, MA 01730-2323, USA; tel: + 1 617-275-3300; fax;+1-617-275-3 705 J M Huber Corp, Solem Division, 4940 Peachtree Industrial Blvd, Suite 340 Norcross, GA 30071, USA; tel: +1-770-441-1301; fax: +1-770-368-9908 Hubron Manufacturing Divn Ltd, Albion Street, Failsworth, Manchester M35 OFP, UK; tel:+44-161-681-2691; fax:+44-161-683-4658 Hiils AG, Paul-Bauman-Str 1 Postf 1320, D-45 764 Marl, Germany; tel: +49-236549-1; fax:+49-23-49-4179 Hiils America Inc, 80 Centennial Ave, PO Box 456, Piscataway, NJ 0 8 8 5 5 0456, USA; tel: +1-908-980-6800; fax: +1-908-981-5497 Huntingdon Fusion Techniques Ltd, Stukeley Meadows, Huntingdon PE18 6EJ, UK; tel: +44-480-412432; fax: + 4 4 - 4 8 0 - 4 1 2 8 4 1 . Huntsman Corporation, 500 Huntsman Way, Salt Lake City, UT 84108, USA; tel: +1-801-584-5700; fax: +1-801-584-5791 I ICI Chlor-Chemicals, PO Box 14, The Heath, Runcorn WA7 40G, UK; tel: +441928-513846;fax:+44-1928-569459 Image Automation Ltd, Kelvin House, Worsley Bridge Road, London SE26 5BX, UK; tel:+44-181-461-5566. Inbra Industrias Quimicas Ltda, Av Fagundes de Oliveira 190, Piraporinha Diadema, SP 09950-907, Brazil; teh +55-11-745-4133; fax: +55-11-7462011 Incemin AG, Schachen 82, CH-5113 Holderbank, Switzerland; tel: +41-62-532627;fax:+41-62-893-2017 Incoe Corp, 2111 Stephenson Highway, PO Box 485, Troy, MI 4 8 0 8 3 , USA; tel:+1-313-689-0220; fax:+1-313-689-3278. Indspec Chemical Corp, 411 Seventh Avenue, Suite 300, Pittsburgh, PA 15210, USA; tel: +1-412-765-0439; fax: +1-412-765-1200 Inducolor SA, De Bavaylei 66, B-1800 Vilvoorde, Belgium; tel: +32-2-2512604; fax:+32-2-252-4567 Industrie Generah SpA, Via Milano 2 0 1 , PO Box 28, 1-21017 Samarate (Va), Italy; tel: +39-331-220-537; fax: +39-331-222-492


347

Instron Ltd, Coronation Road, High Wycombe HP12 3SY, UK; tel: +44-1494464646; fax: +44-1494-456124 IRG Plastics Ltd, Old Wolverton Road, Milton Keynes MK12 5PS, UK; tel: +441908-225600; fax: +44-1908-222607 Ishikawajima-Harima Heavy Industries Co Ltd, 2-2-1, Ohtemachi, Chiyoda-ku, Tokyo 100, Japan; tel: +81-3-3244-5111; fax: +81-3-3244-5131; tx: 22232. Italmaster Sri, Via Somma 72, 1-20012 Cuggiono (Milano), Italy; tel: +39-29724-1328; fax:+39-2-9724-1333 Itoh, C & Co Ltd, 4-1-13, Kyutaromachi, Chuo-ku, Osaka 541, Japan; tel: +81-6241-2121; fax:+81-6-241-3167; tx: 63260.

I Jackdaw Polymers Ltd, Stockton Street, Littleborough 0L15 8YJ, UK; tel: +441706-377115;fax:+44-1706-37793 Jayant Oil Mills, 13 Sitafalwadi, Dr Mascarenhas Road, Mazgaon, Bombay 400 010, India; tel:+91-22-373-8810; fax:+91-22-373-8107 Jayell Plastics (Mktg) Ltd, 4 Hawthornden Manor, Bramshall Road, Uttoxeter ST14 7PH, UK; tel: +44-1889-566-647; fax: +44-1889-566-648 Johnson Controls, Manchester, MI, USA; tel: +1-313-428-8371; fax: +1-313428-9237. Johnson Matthey Electronics, East 15128 EucHd Avenue, Spokene, WA 99216, USA; tel: +1-509-924-2200 Johnson Matthey pic, Precious Metals Division, Orchard Road, Royston SG8 5HE,UK;tel:+44-1763-253-385;fax:+44-1763-253-419 Jotun Polymer A/S, PO Box 2 0 6 1 , Sandefjord N-3201, Norway; tel: +47-334570-00; fax: +47-334-64614 JPSElastomerics,c/oB.LeMonte,Polymar, Belgium; fax+32-3 650 1690 K Kabi Pharmacia AB, 75182 Uppsala, Sweden; tel: +46-1816-3006; fax: +461869-2864 Kali-Chemie AG, Hans-Bockler-Allee 20, Postfach 220 D-3000 Hannover 1, Germany;tel:+49-511-8571; fax:+49-511-282-126 Kalle Pentaplast GmbH, PO Box 11 65, D-56401, Montabaur, Germany; teL+49-2602-915-130; fax:+49-2602-915-179 Kaneka Belgium NV, Nijverheidsstraat 16, B-2260 Westerlo-Oevel, Belgium; tel:+32-1421-494; fax:+32-1321-6223 Kaneka Corp, 3-12, 1-Chome, Motoakasaka, Minato-ku, Tokyo, Japan; tel: + 8 1 3-3479-9647; fax: +81-3-3479-9699 Kaneka Texas Corp, 17 South Briar Hollow, Houston, TX 77027, USA; tel: + 1 713-840-1751; fax:+1-713-552-0133 Karle Finke Farbstoffe, Hatzfelder StraSe 174-176, D-56000 Wuppertal 2, Germany; tel: +49-202-7040-51

348


Kautschuk Gesellschaft mbH, Reuterweg 14, D-6000 Frankfurt, Germany; tel: +49-69-1590; fax: +49-69-1592-125 Kawasaki Steel Corp, 2-2-3, Uchi-Saiwaicho, Chiyoda-ku, Tokyo 100, Japan; tel:+81-3-3597-3111;fax:+81-3-3597-4868 KD Thermoplastics, 119 Guildford Street, Chertsey KT16 9AL, UK; tel: +441932-566033;fax:+44-1932-560363 Kemira Pigments Oy, Speciality Products, FIN-28840 Pori, Finland; tel: +35839-341-000; fax: +358-39-341-919 Kemira Pigments SA, Ave Einstein 11, B-1300 Wavre, Belgium; tel: +32-10232-711;fax:+32-10-229-892 Kemira Polymers, Station Road, Birch Vale, Cheshire SK12 5BR, UK; tel: +441663-746518; fax: +44-1663-746605 Kemutec Group Ltd, Hulley Road, Macclesfield SKIO 2ND, UK; tel: +44-1625428733; fax:+44-1625-427319 Kenrich Petrochemicals Inc, 140 East 22nd Street, PO Box 32, Bayonne, NJ 07002-0032, USA; tel: +1-201-823-9000; fax: +1-201-823-0691 Kerry Ultrasonics Ltd, Hunting Gate, Wilbury Way, Hitchin SG4 OTQ, UK; tel: +44-1462-450761; fax: +44-1462-420712 Kistler Instrument Corp, Amherst, NY 14228-2171, USA; tel: +1-716-6915100; fax:+1-716-691-5226. Kistler Instrumente AG, CH-8408 Winterthur, Switzerland; tel: +41-52831111; fax:+41-52-257200 KMG Minerals, Divn of Franklin Industrial Minerals, 1469 South Battleground Avenue, Kings Mountain, NC 28086, USA; tel: +1-704-739-3616; fax:+1-704-739-7888 Korlin Concentrates, 501 Eric Street, Stratford, Ontario N5A 2N7, Canada; tel:+1-519-271-1680 Krahn Chemie GmbH, Grimm 10, D-2000 Hamburg 11, Germany; tel: +49-403292-0; fax: +49-40-3292-322 Krauss-Maffei AG, Krauss-Maffei-Strafie 2, D-80997 Miinchen, Germany; tel: +49-89-8899-3551; fax: +49-89-8899-2230 Kronos International Inc, Peschstrafie 5, D-513 73 Leverkusen, Germany; tel:+49-214-3560; fax:+49-214-421-50 Kronos Ltd, Barons Court, Manchester Road, Wilmslow SK9 IBQ, UK; tel: +441625-547-200; fax:+44-1625-533-123 K-Tron Great Britain Ltd, 4 Southlink Business Park, Oldham, Lancashire 0L4 IDE, UK; tel: +44-161-626-4580; fax: +44-161-624-2853 Kuraray Co Ltd, Synthetic Rubber and Resin Dept, Maruzen Bldg 3-10, 2-chome, Nihonbashi, Tokyo 103, Japan; tel: +81-3-3277-6654; fax: +81-3-32776666 Kureha Chemical Industry Co Ltd, 1-9-11 Nihonbashi-Horidomecho, Chuo-ku, Tokyo 103-8552, Japan; tel: +81-3-3249-4666; fax: +81-3-3249-4601 Kvaerner A/S, PO Box 100, Skoyen N-0212 Oslo, Norway; tel: +47-22-967000; fax:+47-22-520122 Kyowa Chemical Industry Co. Ltd, 305 Yashima-Nishimachi, Takamatsu-shi, Karawa761-01,Japan; tel:+81-877-47-2500; fax:+81-877-47-4208

Appendix E; Directories

349

L Lab Craft, Church Road, Harold Wood, Romford RM3 OHT, UK; tel: +44-708349320; fax: +44-708-376394. Lanstar Ltd, Liverpool Road, Cadishead, Manchester M30 5DT, UK; tel: +44-61775-2644; fax: +44-61-776-1077 Laporte Worldwide Compounding Group, 170 Pioneer Drive, Leominster, MA 01453, USA; teL +1-978-537-8071 Laporte-AlphaGary Ltd, Wanlip Road, System, Leicester LE7 IPA, UK; tel: +44116-269-6752; fax:+44-116-269-2960 Lapp Insulator Co, 6 Apollo Drive, Batavia, NY 14020, USA; tel: +1-716-3441284; fax:+1-716-344-3872. Latha Chemical Co, 7 Kumarappa Maistry St, Madras 600 0 0 1 , India; tel: + 9 1 518-653 Lati Industria Thermoplastica, Via Baracca 7, 1-21040 Vedano Olona, Italy; tel:+39-332-409-111 Laurel Industries Inc, 30195 Chagrin Blvd, Cleveland, OH 44124-5794, USA; tel:+l-216-831-5747;fax:+1-216-831-8479 Lehmann & Voss & Co, Alsterufer 19, D-2000 Hamburg 36, Germany; tel: +4940-44197-1; fax: +49-40-441-97219 Llewellyn Ryland Ltd, Haden Street, Birmingham B12 9DB, UK; tel: +44-121440-2284; fax:+44-121-440-0281 Lloyd Instruments Ltd, 12 Barnes Wallis Rd, Fareham P015 5SH, UK; tel: +441489-574221; fax:+44-1489-885118 LNP Engineering Plastics Europe BV, Ottergeerde 22-30, NL-4941 VM Raamsdonksveer, The Netherlands; tel: +31-1621-87600; fax: + 3 1 1631-87730 Lodige Maschinenbau GmbH, Postfach 2050, D-33050 Paderborn, Germany; tel: +49-5231-3090; fax: +49-5231-309-123 Lohmann GmbH & Co KG, Irlicher StraSe 55, Postfach 1201 10, D-5450 Neuwied 12, Germany; tel: +49-2631-7860; fax: +49-2631-786467 Lonza AG, Postfach, 5643, Sins, Switzerland; tel: +41-42-660-111; fax: + 4 1 42-662-316 Lonza Inc, 17-17 Route 208, Fair Lawn, NJ 07410, USA; tel: +1-201-7942400; fax:+1-201-794-2515 Lonza SpA, Via Vittor Pisani 31,1-20124 Milan, Italy; teL +39-2-669-991; fax: + 39-2-669-876-30 Lonza-Werke GmbH, Postfach 1580, D-7858 Weil amRhein, Germany; tel: +497621-7030; fax:+49-7621-703-255 Lucky Ltd, Twin Towers Bldg 20 Yoido-Dong, Yongdeung Po-ku, PO Box 672, Seoul, S. Korea; taL +82-2 789 7407; fax: +82-2-787-7766 Luperox GmbH, Denzinger Strafie 7, Postfach 1354 D-8870 Gunzburg/Do, Germany; teL 49-8221-980; fax:+49-8221-98166 Luzenac, 131 Ave Charles de Gaulle, F-92200 Neuilly, France; teL +33-1-47459040; fax: +33-1-4747-5805 Lyondell Chemical Europe Inc, Bridge House, Maidenhead SL6 lYB, UK; tel: +44-1628-77500; fax: +44-1628-775180

350


M Macbeth Divn. of Kollmorgen Instruments Corp., New Windsor, NY, USA; tel:+1-914-565-7660 Magnesia GmbH, PO Box 2168, D-21311 Luneburg, Germany; tel: + 4 9 - 4 1 3 1 52011;fax:+49-4131-53050 Mallinckrodt Specialty Chemicals, 16305 Swingley Ridge Drive, Chesterfield, MO 63017, USA; tel: +1-314-895-2000; fax: +1-314-530-2562 Mannesmann Demag Kunststofftechnik, Altdorfer StraSe 15, D-905 71 Schwaig, Germany; Tel:+49-911-50-61-232; Fax:+49-911-50-09-653. Marcel Dekker Inc, 2 70 Madison Avenue, New York, NY 10016, USA; tel: + 1 212-696-9000. Marine Magnesium Co, 995 Beaver Grade Road, Coraopolis, PA 15108, USA; tel: +1-412-264-0200; fax: +1-412-264-9020 Marion Merrell Dow Inc, 9300 Ward Parkway, PO Box 8480, Kansas City, MO 64114-0480, USA; tel: +1-816-966-4000; fax: +1-816-966-3802 R J Marshall Co, 26776 W Twelve Mile Road, Southfield, MI 48034-7807, USA; tel:+1-313-353-4100; fax:+1-313-948-6460 Martin Marietta Energy Systems Inc, PO Box 2008, Oak Ridge, TN 37831-6266, USA; tel:+1-615-574-4160. Martin Marietta Magnesia Specialties Inc, PO Box 15470, Baltimore, MD 212200470, USA; tel: +1-510-780-5500 Mason Chemical Co, Carolyn House, Dingwall Rd, Croydon CRO 9XF, UK; tel:+44-181-686-5625;fax:+44-181-686-1408 Mastio & Co, 802 Francis Street, St. Joseph, MO 6 4 5 0 1 , USA; tel: +1-816-3646200; fax: +1-816-364-3606. Mayzo Inc, 6577 Peachtree Industrial Blvd, Norcross, GA 30092, USA; tel: + 1 770-449-9066; fax: +1-770-449-9070 Mearl Corp, PO Box 3030, 320 Old Briarcliff Road, Briarcliff Manor, NY 10510, USA; tel: +1-914-923-9500; fax: +1-914-923-9594 Mearl Corporation, 41 East 42nd Street, New York, NY 10017, USA; tel: + 1 212-573-8500; fax:+1-212-557-0742 Mearl International BV, Emrikweg 18, 2031 BT Haarlem, The Netherlands; tel:+31-23-318-058;fax:+31-23-351-365 Megret Ltd, Woodlands, Ashcroft Road, Knowsley Industrial Park, Merseyside L33 7TW, UK; tel:+44-151-548-6800; fax:+44-151-547-5700 Meiki Co Ltd, 2, Ohne, Kitazaki-cho, Ohbu City, Aichi Prefecture 474, Japan; tel:+81-562-48-2111;fax:+81-562-47-2316 Mercator Inc, 560 Sylvan Avenue, Englewood Cliffs, NJ 07632, USA; tel: + 1 201-569-3533; fax:+1-201-569-7368 Merck E, Sparte Pigmente und Kosmetik, Frankfurter StraKe 250, D-64293 Darmstadt 1, Germany; tel: +49-6151-72-6309; fax: +49-6151-72 7684 Mergon International Ltd, 1 0 9 - 1 1 1 Ballards Lane, Finchley, London N3 IXY, UK; tel: +44-81-346-0744; fax: +44-81-346-2699. Merit (Malta) Ltd, PO Box 117, Valletta, Malta; tel: +356-484-184; fax: +356446-679


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Merritt Davis Corp, 15 Marne Street, Hamden,CT 06514, USA; tel:+1-203-2308100; fax: +1-203-230-8989 Metalgesellschaft AG, Postfach 10 15 0 1 , Reuterweg 14, Frankfurt am Main 1, Germany; tel:+49-69-1590; fax:+49-69-159-2125 Mettler Toledo Ltd, 64 Boston Road, Leicester LE4 lAW, UK; tel: +44-116-2357070; fax:+44-116-236-6399 MGI-Coutier, 27 rue de Lisbon, Paris 75008, France; tel: +33-1-4289-3122; fax:+33-1-4562-8985. Microban International, 1221 Avenue of the Americas, 24th Floor, New York, NY 10020, USA; tel: +1-212-332-8730; fax: +1-212-332-8739 Micromet Instruments Inc, 7 Wells Avenue, Newton Centre, MA 02159, USA; tel:+1-617-969-5060; fax:+1-617-959-5040 Micropol Ltd, Bayley Street, Stalybridge, Cheshire SK15 IQQ, UK; tel: +44-161330-5570; fax:+44-161-330-7687 MilesIncMobayRoad, Pittsburgh, PA 15205-9741, USA; tel:+1-412-777-2000 Millennium Inorganic Chemicals Inc, 200 International Circle, Suite 5000, Hunt Valley, MD 21030, USA; tel: +1-410-229-4400; fax: +1-410-2294488 Milliken Chemical Divn, Milliken & Co, M-400 PO Box 192 7, Spartanburg, SC 29304-1927, USA; tel: +1-864-503-2200; fax: +1-864-503-2430 Milliken Chemical, Ham 18-24, B-9000 Gent, Belgium; tel: +32-9-265-1084; fax:+32-9-265-1195 Millinckrodt Specialty Chemicals Europe, Postfach 1268, Industriestrafie 19-21, D 6110 Dieburg, Germany; tel: +49-6071-200-40; fax: +49-6071-200-444 MIR UK Ltd, Unit 2, 15 Headley Road, Woodley, Reading RG5 5JB, UK; tel: +44734-441037; fax: +44-734-441045. MIRC Europe SA, 54 rue Vandenhoven, B-1150 Brussels, Belgium; tel: +32-2762-2781; fax:+32-2-771-7248 MIRC USA, 2525 Charleston Road, Mountain View, CA 9 4 0 4 3 , USA; tel: + 1 415-961-9000; fax:+1-415-961-5042 MIRC/NSI Japan, Schon Lebrn Yoshida Building, 3-9-15, Nishi-Gotanda, Shinagawa- ku, Tokyo 141, Japan; tel: +81-3-5434-2730; fax: +81-35434-2733. Mitsubishi Chemical Co Ltd, 2-5-2, Marunouchi, Chiyoda-ku, Tokyo 100, Japan; tel:+81-3-3283-6111;fax:+81-3-3287-0833 Mitsubishi Kasei Corp, 2-5-2, Marunouchi, Chiyoda-ku, Tokyo 100, Japan; tel:+81-3-3283-6254; fax:+81-3-3283-6787 Mitsubishi Petrochemical Co Ltd, 2-5-2, Marunouchi, Chiyoda-ku, Tokyo 100, Japan; tel: +81-3-3283-5700; fax: +81-3-3283-5805 Mitsubishi Rayon Co Ltd, 2-3-19 Kyobashi, Chuo-ku, Tokyo 104-0031, Japan; tel: +81-3-3245-8765; fax: +81-3-3245-8782 Mitsui & Co Deutschland GmbH, Konigsallee 63-65, D-40215 Diisseldorf, Germany;tel:+49-211-9386-347; fax:+49-211-9386-348 Mitsui Petrochemical Industries Co Ltd, Kasumigaseki Building, 3-2-5, Kasumigaseki, Chiyoda-ku, Tokyo 100, Japan; tel: +81-3-3580-3616; fax: +81-3-3593-0028.

352


Mitsui Toatsu Chemicals Inc, 3-2-5, Kasumigaseki, Chiyoda-ku, Tokyo 100, Japan; tel:+81-3-3592-4111; fax:+81-3-3592-4267 Moldflow Singapore, Orchard, PO Box 0745, Singapore 9123; tel: +65-7386760; fax:+65-738-2783. Moldflow (Europe) Ltd, Central Court, Knoll Rise, Orpington BR6 OJA, UK tel:+44-1689-878-111; fax:+44-1689-878-678 Monsanto Chemicals SA, Av de Tervuren 2 70-272, B-1150 Brussels, Belgium tel:+32-2-761-4111; fax:+32-2-761-4040 Monsanto Company, 800 N. Lindbergh Boulevard, St Louis, MO 63167, USA tel:+1-314-694-5274 Montedison SpA, Fuoro Buonaparte 31,1-20121 Milano, Italy; tel: +39-2-62 705519;fax:+39-206270-5268 Montell Polyolefins, Functional Chemicals, Three Little Falls Centre, 2801 CentervilleRoad,POBox 15439, Wilmington, DE 19850-5981, USA Montell Polyolefins, Woluwe Garden, Woluwedal 24, B-1932 Zaventem, Belgium; tel: +32-2-715-8164; fax: +32-2-715-8264 Morton International Inc, Morton Plastics Additives, 2000 West Street, Cincinnati, OH45215-3431, USA; tel:+1-513-733-2100; fax:+1-513-733-2133 Multibase Inc, 3835 Copley Road, Copley, OH 4 4 3 2 1 , USA; tel: +1-216-8675124;fax:+1-216-666-7419 Multibase SA, ZI du Guiers, F-38380 Saint-Laurent-du-Pont, France; tel: + 3 3 76-67-1212; fax: +33-76-67-1292 Murtfeldt GmbH & Co KG, Postfach 120161, D-4600 Dortmund 12, Germany; tel:+49-231-251-012; fax:+49-231-251-021

N NEC Corp, 5-7-1 Shiba, Minato-ku, Tokyo 108-8001, Japan; tel: +81-3-3454llll;fax:+81-3-3457-7249 Negri Bossi spa, Viale Europa 64, 20093 Cologno, Monzese, Milan, Italy; tel:+39-2-273-02545; fax:+39-2-253-8264. Nemitz Kunststoff-Additive GmbH, PO Box 122 7, D-48338 Altenberge, Germany; tel: +49-2505-674; fax: +49-2505-3042 Neocrin Co, 1202 East Neocrin Avenue, Santa Ana, CA 92 705, USA; tel: + 1 714-541-1606; fax: +1-714-541-5423. Neste Chemicals, PO Box 20, SF-02151 Espoo, Finland; tel: +358-0-450-5044; fax:+358-0-450-4985 Neste Oy, Corporate Head Office, Keilaniemi, PO Box 20, SF-02151 Espoo, Finland; tel:+358-0450-1; fax:+358-0450-4447 Neste Polymer Compounds AB, Sweden; tel: +46-8-709-6552; fax: +46-8-7096590. Neu Engineering Ltd, Planet House, Guildford Road, Woking GU22 7RL, UK; tel:+44-1483-756-565; fax:+44-1483-755-177 Nevicolor SpA, Via Maso 2 7, 1-42045 Luzzara (Regio Emilia), Italy; tel: +39522-9764-21; fax: +39-522-9765-69


353

Nihon Kakaku Sangyo Co Ltd, 20-5 Shitaya 2-chome, Taito-ku, Tokyo 110, Japan; tel:+81-3-3876-3131; fax:+81-3-3876-3278 Niigata Engineering, 1-4-1 Kasumigaseki, Chiyoda-ku, Tokyo 100, Japan; tel:+81-3-3504-2182; fax:+81-3-3595-2648 Nikkan Kogyo Shimbun Ltd, International Division Office, 5F, Kobu Building, 1-2-14, Shinkawa, Chuo-ku, Tokyo 104, Japan; tel: +81-3-5543-0144; fax:+81-3-5543-0212. Niplast Engineering, 187 Higher Hillgate, Stockport SKI 3JG, UK; tel: + 4 4 - 6 1 477-6777; fax: +44-61-429-8413. Nippon Paint Co Ltd, 2-1-2, Oyodokita, Kita-ku, Osaka 5 3 1 , Japan; tel: +81-6458-1111; fax:+81-6-455-9260 Nippon Shokubai Co Ltd, Kogin Building, 4-1-1, Koraibashi, Chuo-ku, Osaka 541,Japan; tel:+81-6-223-9111;fax:+81-6-201-3716 Nippon Steel Chemical Co Ltd, 5-13-16, Ginza, Chuo-ku, Tokyo 104, Japan; tel:+81-3-3542-1321; fax:+81-3-3546-3575 Nippon Steel Corp, 2-6-3, Ohtemachi, Chiyoda-ku, Tokyo 100-71, Japan; tel:+81-3-3242-4111;fax:+81-3-3275-5611 Nissei Plastic Industrial Co. Ltd, 2110 Minamijo, Sakaki-machi, Nagano 383-06 Japan; tel: +81-268-81-1070; fax: +81-268-81-1098 Nissin Electric Co Ltd, 47 Umezu-takase-cho, Ukyo-ku, Kyoto 615, Japan; teL+81-75-861-3151;fax:+81-75-872-0742 Nitto Chemical Industry, 1-5-1 Marunouchi, Chiyoda-ku, Tokyo 100, Japan; tel:+81-3-3271-0251; fax:+81-3-3287-2725 NOP Corporation, Yurakucho Bldg 2-8 Toranomon 1-chome, Chiyoda-ku, Tokyo 100, Japan; tel: +81-3-3283-7295; fax: +81-3-3283-7178 Normann Rassmann GmbH & Co, Kajen 2, D-2000 Hamburg 11, Germany; tel: +49040-368-70; fax: +49-40-368-7249 Norsk Hydro Petrochemicals Division, Bygdoy AUe 2, N-0240 Oslo 2, Norway Novalis Fibres, 129 rue Servient BP 3052, Lyon Cedex 03, France; tel: +33-786280-47 Nyco Minerals Inc, 124 Mountain View Drive, Willsboro, NY 12996-0368, USA; tel:+1-518-963-4262; fax:+1-518-963-4187 Nyco Minerals Inc, Europe, Ordrupvej 24, PO Box 88, DK-2920 Charlottenlund, Denmark; tel:+31-64-3370; fax:+31-64-3710

O Obron Atlantic Corporation, PO Box 747, Painsville, OH 44077, USA; tel:: + 1 216 3 5 4 0 4 0 0 ; fax:+1-216-354-6224 Occidental Chemical Corp, Occidental Tower, LBJ Freeway, Dallas, TX 75244, USA; tel: +1-214-404-3800; fax: +1-214-404-2333 Occidental Chemical Corp, Technology Center, 2801 Long Road, Grand Island, NY 14072, USA; tel: +1-716-773-8100 Occidental Chemical Europe SA, Holidaystraat 5, B-1831 Diegem, Belgium; tel: +32-2-715-6600; fax:+32-2-725-4676

354


Oima SpA, Via Feltrina Sud 172, 31044 Montebelluna/TV, Italy; tel: + 3 9 - 4 2 3 6 0 0 5 4 1 ; fax:+39-423-24035 Olin Corporation, 120 Long Ridge Road, PO Box 1355, Stamford, CT 06904, USA; tel:+1-203-356-3036; fax:+1-203-356-3273 Olin Japan Inc, Shiozaki Bldg, 7-1 Hirakawa-cho 2-chome, Chiyoda-ku, Tokyo 102,Japan;tel:+81-3-263-4615; fax:+81-3-023-24031 OM Group Inc, 2301 Scranton Road, Cleveland, OH 4 4 1 1 3 , USA; tel: +1-216781-8383; fax:+1-216-781-5919 Omya GmbH, Brohler StraBe 11a, D-50968 Koln, Germany; tel: +49-221-3775-0; fax:+49-221-3718-64 Ore and Chemical Corp, 520 Madison Ave 2 7th Floor, New York, NY 10022, USA; tel:+1-212-715-5237; fax:+1-212-486-2742 Ormecon Chemie GmbH & Co KG, Ferdinand-Harten-StraEe 7, D-22949 Ammersbek, Germany Osi Specialties Inc, 39 Old Ridgebury Rd, Danbury, CT 06810-5124; tel: + 1 203-794-3402; fax: +1-203-794-3088 Otsuka Chemical Co, 2-2 7 Ote-dori 3-chome, Chuo-ku, Osaka 540, Japan; tel:+81-6-943-7711; fax:+81-6-946-0860 Overbeck Handelsgesellschaft mbH & Co, Breitenweg 29-33, D-28195 Bremen, Germany; tel: +49-421-3092-204; fax: +49-421-3092-337 Owens Corning Europe, Chaussee de la Hulpe, B 1170 Brussels, Belgium; tel:+32-2-674-8211-178;fax:+32-2-660-8572 Owens Corning World HQ, Fiberglas Tower, Toledo, OH 43659, USA; tel: + 1 419-248-8000 Oxford Instruments Inc. Analytical Systems Division, 130a Baker Avenue Extension, Concord, MA 01742, USA; tel: +1-508-371-9009; fax: + 1 508-371-0204 Oxyplast Belgium NV/SA, Nek-kersputstraat 189, D-9000 Gent, Belgium; tel:+32-9-216-8870; fax:+32-9-227-4116 P Pan Polymers Ltd, Unit K, Penfold Works, Imperial Way, Watford WD2 4YY, UK; tel:+44-923-211244; fax:+44-923-253530. Papenmeier GmbH Mischtechnik, Postfach 2140, D-32828 Augustdorf, Germany; tel: +49-5237-690; fax: +49-5237-692-31 Patco Polymer Additives, American Ingredients Co, 3947 Broadway, Kansas City, MO 64111, USA; tel: +1-816-561-9050; fax: +1-816-561-0422 PCD Polymere, DanubiastraSe 21-25, A-2323 Schwechat-Mannsworth, Austria; tel:+43-1-701-11; fax:+43-1-701-11-310 PCI, Yautepec 133, Col Condesa, Mexico DF 06140; tel: +52-5553-1172; fax: + 52-5256-3354 PCME Ltd, Clearview Building, Edison Road, St Ives PE17 4GH, UK; tel: +441480-468200; fax: +44-1480-463400 PEC GmbH, KonigstraSe 37-43, D-5202 Hennef 1, Germany; tel: +49-22425091; fax: +49-2242-1244


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Penn-White Ltd, Radnor Park Trading Estate, CongletonCN12 4XJ, UK; tel: +441260-279-631; fax:+44-1260-278-263 Pergan GmbH, Schlavenhorst 71, D-46395 Bocholt, Germany; tel: + 4 9 - 2 8 7 1 99-020; fax: +49-2871-99-0250 Peroxid-Chemie GmbH, Dr-Gustav-Adolph-StraSe 3, D-82049 Pullach, Germany; tel: +49-89-74422-0; fax: +49-89-74422-203 Phillips Chemical Co, 411 Keeler, Bartlesville, OK 74004, USA; tel: + 1 - 9 1 8 - 6 6 1 4400; fax: +1-918-661-7636 Phillips Petroleum International NV, Haendorpweg 1 - Haven 122 7, B-9130 Kallo-Beveren, Belgium; tel:+32-3-570-2611; fax:+32-3-570-2626 Phipps Group, Unit 5, Hattersley Industrial Estate, Hyde, Cheshire SKI4 30T, UK; tel: +44-161-367-8789; fax: +44-161-367-8787 Pierce & Stevens Corporation, 710 Ohio Street (14072) Box 1092, Buffalo, NY 14240, USA; tel: +1-716-856-4910; fax: +1-716-856-7530 Pilot Industries, Technical Center, 2319 Bishop Circle East, Dexter, MI 48130, USA; tel:+1-313-426-4376; fax:+1-313-426-8160 Plalloy MTD BV, Postbox 3035, 6460 HA Kerkrade, The Netherlands; tel: + 3 1 45-546-4653;fax:+31-45-536-2523 Plastichemix Industries, 6 Kirti Towers, Tilak Road, Vadodara 390 0 0 1 , India; tel: +91-265-421-844; fax: +91-265-422-129 Plasticolors Inc, 2600 Michigan Avenue, Ashtabula, OH 44004, USA; tel: + 1 216-997-513 7; fax:+1-216-992-3613 Plastics Plus Ltd, Unit 9, Wulfrun Trading Estate, Stafford Road, Wolverhampton WV10 6HR, UK; tel:+44-902-715131; fax:+44-902-715096 Plast-0-Matic Valves Inc, 430 Route 46, Totowa, NJ 07512, USA; tel: + 1 - 2 0 1 256-3000; fax: +1-201-256-4745 Polar Minerals, 5060 North Royal Atlanta Drive, Suite 22, Tucker, GA 30084, USA; tel:+1-404-934-4411; fax:+1-404-934-43 76 Polycolour Plastics Ltd, Unit F l , Halesford 2 1 , Telford TF7 4NX, UK; tel: +441952-581814; fax:+44-1952-581815 Polymer Corp, 2120 Fairmont Avenue, PO Box 14235, Reading, PA 196124235,USA; tel:+1-215-320-6600; fax:+1-215-476-1196. Polymer Laboratories Ltd, Essex Road, Church Stretton SY6 6AX, UK; tel: +441694-723581; fax:+44-1694-722171 Polyplastics Co Ltd, Kasumigaseki Building, 3-2-5 Kasumigaseki, Chiyoda-ku, Tokyo 100,Japan; tel:+81-3-3593-2444; fax:+81-3-3580-0629 Polyrex Additives, Rte de Lausanne 23, CH-1400 Yverdon-les-Bains, Switzerland; tel: +41-24-2245-63; fax: +41-24-2245-64 Polyvel Inc, 120 N White Horse Pike, Hammonton, NJ 0803 7, USA; tel: +1-609567-0080; fax: +1-609-567-9522 Porous Plastics Ltd, 8 Little Park Farm Rd, Segensworth, Fareham P 0 1 5 5TB, UK; tel: +44-1489-577623. Portwood Colour Co. Ltd, 17-19 Rochdale Road, Bury BL9 OQB, UK; tel: +44161-764-5891; fax:+44-161-761-5763 Potters Industries Inc, Southpoint Corporate Headquarters, PO Box 840, Valley Forge, PA 19482-0840, USA; tel: +1-610-651-4700; fax: +1-610-408-9723

356


Potters-Ballotini, Postfach 12 03 33, D-40603 Dusseldorf, Germany; tel: +49211-29608-0; fax:+49-211-29608-18 PPG Industries Fiber Glass BV, PO Box 50, NL-9600 AB Hoogezand, The Netherlands; tel:+31-5980-13911; fax:+31-5980-99649 PPG Industries Inc, One PPG Place, Pittsburgh, PA 15272, USA; tel: +1-412434-2261; fax: +1-412-434-2821 PQ Corporation, Box 840, Valley Forge, PA 19482, USA; tel: +1-610-651-4200; fax:+1-610-251-9124 Prayon-Rupel SA Societe Chimique, Gansbroekstraat 3 1 , B-2870 Puurs (Ruisbroek-Antwerp), Belgium; tel:+32-3-860-9200; fax:+32-3-886-3038 Precision Polymer Engineering Ltd, Clarendon Road, Blackburn BBl 9SS, UK; tel:+44-1254-679916; fax:+44-1254-680182 Premix Oy, PO Box 12, 05201 Rajamaki, Finland; tel: +358-0-290-1066; fax: + 358-0-290-3135 Provencale SA, 29 av Frederick Miatral, 83174 Brignoles Cedex, France; tel: +33-4-9472-8300; fax: +33-4-9459-0455 Priiftechnik AG, Oskar-Messter-Strafie 19-21, Postfach 1263, 8045 Ismaning, Germany; tel: +49-89-99616-0; fax: +49-89-99616-200.

Q Quantum Chemical Co, 11500 Northlake Drive, PO Box 429550, Cincinnati, OH 45249, USA; tel:+1-513-530-6500; fax:+1-513-530-6313 Quantum Materials, 9938 Via Pasar, San Diego, CA 92126, USA; tel: +1-619695-1716;fax:+1-619-695-0951 Quartz & Silice, BP 103, F-77793 Nemours Cedex, France; tel: +33-1-64454600; fax:+33-1-6428-4511 Quimica Roveri Commercial Ltda, Rua Alvaro Fragoso 344, Vila Carioca, Sao Paolo/SP04223-000,Brazil;tel:+55-11-2 74-3466; fax:+55-11-63-5659 R James Robinson Ltd, PO Box 83, Hillhouse Lane, Huddersfield HDl 6BU, UK; tel:+44-1484-435-577; fax:+44-1484-435-580 Raschig AG, Postfach 211128, D-6700 Ludwigshafen, Germany; tel: + 4 9 - 6 2 1 56180; fax:+49-621-5828-85 Raychem Ltd, Faraday Road, Dorcan, Swindon SN3 5HH, UK; tel: + 4 4 - 1 7 9 3 528171;fax:+44-1793-572276 Reagens, 1-40016 San Giorgio di Piano (Bologna), Italy; tel: +39-51-897-157; fax:+39-51-897-561 Redland Minerals, PO Box 2, Retford Road, Worksop S81 7QQ, UK; tel: +441909-537-800; fax:+44-1909-537-801 ReedSpectrum, Holden Industrial Park, Holden, MA 10520, USA; tel: +1-508829-6321 Reedy International Corp, 25 East Front St, Suite 200, Keyport, NJ 0 7 7 3 5 , USA; tel:+1-908-264-1777; fax:+1-908-264-1189


357

Reheis Inc, PO Box 609, 235 Snyder Ave, Berkeley Heights, NJ 07922, USA; tel: +1-908-464-1500; fax: +1-908-464-7726 Reichhold A/S, PO Box 2061,N3202 Sandefjord, Norway Reichhold Chemicals Inc, Research Triangle Park, NC 27709, USA; tel: +1-919990-7500 Reifenhauser GmbH, Spicher StraSe 46-48, 53839 Troisdorf-Sieglar, Germany; tel:+49-2241-4810; fax:+49-2241-408778 Reinhold Chemie AG, CH-5212 Hansen bei Brugg, Switzerland; tel: +41-56482-222; fax:+41-56-482-376 Repi SpA, Via del Vecchia Stazione 104-106, 1-21050 Gorla Maggiore (Va), Italy; tel:+39-331-614-001; fax:+39-331-619-537 Resart GmbH, Postfach 34 40, D-6500 Mainz, Germany; tel: +49-6131-631-0; fax:+49-6131-631-142 Research Development Corp, 2-5-2, Nagata-cho, Chiyoda-ku, Tokyo 100, Japan; tel: +81-3-3507-3052; fax: +81-3-3581-1486. Research Engineers Ltd, Orsman Road, London N l 5RD, UK; tel: +44-171-7397811; fax:+44-171-739-6615 Resinas Sinteticas, SA, Ctra. Olzinelles, s/n, E 08470 Sant Celoni, Spain; tel: +34-3-867-4000; fax: +34-3-867-2454 Recticel Nederland BV, Spoorstraat 69, 4041 CL Kesteren, Postbus 1, 4040 DA Kesteren,TheNetherlands; tel:+31-8886-9999; fax:+31-8886-2863. Rhein Chemie Rheingau GmbH, Postfach 81 04 09, D-68204 Mannheim, Germany; tel: +49-621-8907-0; fax: +49-621-8907-555 Rheochem Manufacturing Co, 775 Mountain Boulevard Ste 214, Watchung, NJ 07060, USA; tel: +1-908-757-0300; fax: +1-908-757-0607 Rheometric Scientific Ltd, Kiln Lane, Epsom KT17 IJS, UK; tel: +44-13 72743386; fax:+44-1372-727102 Rhone-Poulenc Chemicals, Secteur Specialites Chimiques, Cedex No 29, F-92097, Paris-La Defense, France; tel: +33-1-4768-1234; fax: +33-14768-1331 Rhone-Poulenc Chimie, Les Miroirs, La Defense 3, Cedex 29, 92097 Paris La Defense, France; tel: +33-1-47-68-1234; fax: +33-1-47-68-1911 Rhone-Poulenc Inc, CN 7500 Cranbury, NJ 08512-7500, USA; tel: +1-609860-4000 Rika International Ltd, 3C Brookside Business Park, Chadderton, Oldham M24 IGS, UK; tel:+44-161-655-4100; fax:+44-161-655-4200 Rim Cast, Cunliffe Drive, Kettering NN16 8LD, UK; tel: +44-536-510616; fax: +44-536-411236 Rite Systems, 1131 Douglas Road, Batavia, IL 60510, USA; tel: +1-630-8799700; fax: +1-630-879-9490 Roche Products Ltd, Heanor Gate, Heanor DE75 7SG, UK; +44-1773 536500; fax:+44-1773-536600 Rockware Plastics Ltd, Skerne Road, Kingston-upon-Thames, Surrey KT2 5AE, UK; teh +44-181-546-1161; fax: +44-181-547-0204 Rogers Corp, 1 Technology Drive, Rogers, CT 0 6 2 6 3 , USA; tel: +1-203-7749605;fax:+1-203-774-1973.

358


Rogers Corporation, Molding Materials Division, PO Box 550, Manchester, CT 06045, USA; tel: +1-860-646-5500; fax: +1-860-649-2389 Rohm & Haas Co, Independence Mall West, Philadelphia, PA 19105, USA; tel:++l-215-592-3000 Rohm and Haas Co, Independence Mall West, Philadelphia, PA 19105, USA; tel:+1-215-592-3000 Rohm and Haas Deutschland GmbH, In der Kron 4, D-1000 Frankfurt/Main 90, Germany; tel: +49-69-789-960; fax: +49-69-789-5356 Rohm GmbH, Postfach 10 01 4 1 , D-64201 Darmstadt, Germany; tel: +496151-18-01; fax:+49-6151-18-02 Rosand Precision Ltd, Balds Lane, Lye, Stourbridge DY9 8SH, UK; tel: +441384-422991; fax:+44-1384-422755 Roth Scientific Co Ltd, Roth House, 12 Armstrong Mall, The Summit Centre, Farnborough, Hampshire GU14 ONR, UK; tel: +44-252-513131; fax: +44252-543609. RTP Co, 580 E Front Street, PO Box 5439, Winona, MN 55987-0439, USA; tel: +1-507-454-6900; fax: +1-507-454-8130 Ruhr-Chemie, HugenottenstraSe 105, Postfach 1429, D-6382 Friedrichsdorf, Germany; tel:+49-6172-733-283; fax:+49-6172-733-141 RV Chemicals Ltd, Widnes, Cheshire WAS OTE, UK; tel: +44-151-424-6101; fax:+44-151-420-4330 S A. Schulman Inc. 3550 West Market Street, Akron, OH 4 4 3 3 3 , USA; tel: + 1 216-666-3751 Sachtleben Chemie GmbH, Postfach 170454, D-47184 Duisburg, Germany; tel: +49-2066-22-0; fax: +49-2066-22-2000 Sandvik Process Systems Ltd, PO Box 3506 Manor Way, Halesowen B62 8QX, UK; tel:+44-121-550-7671 Sanyo Chemical Industries Ltd, 11-1 Ikkyo Nomoto-cho, Hashiyama-ku, Kyoto 605,Japan;tel:+81-75-541-4311;fax:+81-75-551-2557 Sarma, Via Lainate 26, lOOlO PogUano Milanese (Mi), Italy; tel: +39-2-93255363 Sartomer Co Oaklands Corporate Center, 468 Thomas Jones Way, Exton, PA 19341,USA;tel:+l-215-363-4117;fax:+1-215-363-4140 Satim, 57 Z.l route de Lesgor, 40370 Rion-des-Landes, France; tel: +33-58571887;fax:+33-5857-1718. Saudi Basic Industries Corp, PO Box 5 1 0 1 , Riyadh 11422, Saudi Arabia; tel: +966-1-401-2033; fax: +966-1-401-3831 SCJ Plastics Ltd, F-3/10-11, Okha Industrial area, Phase-1, New Delhi 119 020, india;tel:+91-ll-681-5566;fax:+91-11-681-4455 Scapa Polymeries, Columbine St, Manchester M i l 2LH, UK; tel: +44-161-3203636; fax:+44-161-335-0104 Schenck Ltd, Station Approach, Bicester 0X6 7BZ, UK; tel: +44-869-321321; fax:+44-869-321111.


359

Schering AG, Waldstrafie 14, D-4709 Bergkamen, Germany; tel: +49-2307651; fax: 49-2307-69805 Schuller Mats and Reinforcements, PO Box 517, Toledo, OH 43697-0517, USA; tel:+1-419-878-1504 SCM Chemicals - Asia/Pacific, Lot 4 Old Coast Road, Australind, WA 6230, Australia; tel:+61-97-251-261; fax:+61-67-252-504 SCM Chemicals - Europe, PO Box 26, Grimsby South Humberside DN3 7 8DP, UK; tel: +44-1469-571000; fax: +44-1469-571234 SCM Chemicals World HQ, 7 St Paul St, Suite 1010, Baltimore, MD 21202, USA; tel:+1-410-783-1120; fax:+1-410-783-1087 Scortec European Marketing, BTG, 101 Newington Causeway, London SEl 6BU, UK; Tel: +44-20 7403-6666; Fax: +44-20 7403 7586 Sekisui Chemical Co Ltd, 2-4-4, Nishi-Tenma, Kita-ku, Osaka 530, Japan; tel: 81-6-365-4122;fax:+81-6-365-4370 SFR Industries Inc, 652 Tower Drive, PO Box 3 70, Cadott, WI 5472 7-03 70, USA;tel:+1-715-289-4440; fax:+1-715-289-4446 SGL Carbon Group, Speciality Graphite Business Unit, DrachenburgstraKe 1, D-53170 Bonn, Germany; Tel: +49-228-841-0; Fax: +49-228-841-456 SGL Technik GmbH, Werner von Siemens Strage 18, Postfach 1233, D-86405 Meitingen, Germany; tel:+49-8271-832149; fax:+49-8271-832351 Shell International Chemical Co Ltd, Shell Centre, London SEl 7PG, UK; tel: +44-171-934-1234;fax:+44-171-934-5252 Sherwin-William Chemicals, 1700 W Fourth Street, Coffeyville, KS 673 3 7, USA; tel:+1-316-7276 Shimadzu Europa UK, Mill Court, Featherstone Road, Milton Keynes MK12 5RE, UK; tel:+44-1908-552200; fax:+44-1908-552211 Showa Denko KK, 1-13-9, Shiba-Daimon, Minato-ku, Tokyo 105, Japan; tel: + 81-3-5470-3111; fax:+81-3-3431-6442 Silberline Ltd, Banbeath Road, Leven, Fife KY8 5HD, UK; tel: +44-1333-424734; fax: +44-1333-421-369 Silicone Altimex Ltd, 49 Pasture Road, Stapleford, Nottingham NG9 8HR, UK; tel:+44-115-949-1413; fax:+44-115-949-0468 Simco (Nederland) bv, Postbus 11, NL-7240 AA Lochem, The Netherlands; tel:+31-5730-88333; fax:+31-5730-57319. Simeon Kunststofftechnische Software GmbH, D-52134 Herzogenrath, Germany; tel: +49-2407-5088; fax: +49-2407-59453 Sinloihi Co. Ltd, Kita-Yaesu Bldg, 3F 3-2-11 Nihonbashi, Chuo-ku, Tokyo, Japan;tel:+81-3-3281-1255;fax:+81-3-3281-1881 Sintex Ltd, Pavilion 3, Segensworth West, Fareham P015 5TB, UK; tel: +44489-577623;fax:+44-489-885325. Sintimid Hochleistungs Kunststoffe GmbH, Postfach 138, A-6600 Reutte/Tirol, Austria; tel: +43-5672-702625; fax: +43-5672-70501 SIPA SpA, Via Podgora, 31029 Vittorio Veneto TV, Italy; tel: +39-438-501447 SKWTrostberg AG, POBox 1262, D-83303 Trostberg, Germany; tel: + 4 9 - 8 6 2 1 86-2460; fax: 49-8621-86-2020 Slide Products Inc, PO Box 156, Wheeling, IL 60090, USA; tel: +1-708-541-7220

360


SN2A, BP 98, F-13133 Berre TEtang, France; tel: +33-42-10-2242; fax: + 3 3 42-74-1015 SNCI, F-74490 Saint-Jeoire-en-Faucigny, France; tel: +33-50-35-9520; fax: + 33-50-35-9701 SNC-Lavalin, 2 Place Felix Martin, 14th Floor, Montreal, Quebec, Canada H2Z 1Z3; tel: +1-514-393-1000; fax: +1-514-954-0267. Snia BPD Group, Via Stabilimenti 11, 20020 Ceriano Laghetto (Mi), Italy; tel:+39-2-96161 Soarus LLC, 3930 Ventura Drive, Suite 440, Arlington Heights, IL 760004, USA; tel: +1-847-255-1211; fax: +1-255-4343 Solem Europe, PO Box 2 4 1 , NL-9640 AE Veendam, The Netherlands; tel: + 3 1 5987-51390; fax:+31-5987-51393 Solomat Partners LP, 652 Glenbrook Road, Stamford, CN 06906, USA; tel: + 1 203-977-8161; fax:+1-203-977-8237. Solutia Europe NV/SA, Rue Laid Burniat 3, Pare Scientifique - Fleming, B-1348 Louvain-la-Neuve (Sud), Belgium; tel: +32-10-48-13-21; fax: +32-10-4812-24 Solutia Inc, 10300 Olive Boulevard, PO Box 66760, St Louis, MO 63166-6760, USA; tel:+1-314-674-1000 Solvay Deutschland GmbH, Hanover, Germany; tel: +49-511-85 7-3023; fax: +49-511-857-2305. Solvay et Cie, Rue du Prince Albert 33, B-1050 Brussels, Belgium; tel: +32-2509-6111; fax:+32-2-509-51393 Solvay Engineered Polymers Inc, 1200 Harmon Road, Auburn Hills, MI 48326, USA; tel: +1-248-391-9500; fax: +1-248-391-9501 Sonics & Materials Inc, Kenosia Avenue, Danbury, CT 06810, USA; tel: +1-203744-4400; fax:+1-203-798-8350. Sorema SRI, Via Per Cavolto 17, 22040 Anzano del Parco, Como, Italy; tel: +3931-631637; fax:+39-31-631911. Stalo-Chemicals GmbH, Postfach 1606, D-49383 Lohne, Germany; tel: +494442-9430; fax: +49-4442-943-200 Statoil Petrochemicals & Plastics, Stig Mattsson, Poland; tel: +48-51-807872; fax:+48-51-805560. Struktol Co of America, 201 E Steels Corners Road Box 1649, Stow, OH 442240649 USA; tel: +1-216-928-5188; fax: +1-216-928-8726 Subhash Chemical Industries, S Block Shed W-2 MIDC, Bhosari Poona, 411026 MaharashtraState, India; tel:+91-212-790-632; fax:+91-212-792-554 Sudwest-Chemie GmbH, Postfach 2120, D-7910 Neu-Ulm, Germany; tel: +49731-70141; fax: +49-731-707-0764 Sulzer Technology Corp, Sulzer Marketing Services, Farnborough GU14 7LP, UK; tel:+44-1252-525336 Sumitomo Chemical Co Ltd, 4-5-33, Kitahama, Chuo-ku, Osaka 5 4 1 , Japan; tel:+81-6-220-3272; fax:+81-6-220-3345 Sun Chemical Corporation, 222 Bridge Plaza South, Fort Lee, NJ 07024, USA; tel: +1-201-224-4600; fax: +1-201-224-4392 Synco Sri, Via G Rossini 21,1-50041 Calenzano (Fi), Italy; tel: +39-55-8878-201


361

Syncoglas NV, Drukkerijstraat 9, B-9240 Zele, Belgium; tel: +32-52-457-611; fax:+32-52-449-502 Synthecolor SA, 7 rue des Oziers, ZI du Vert Galant, F-95310 Saint-Ouen L'Aumone, France; tel:+33-1-3440-3950; fax:+33-1-3464-0515 Thomas Swan & Co Ltd, Crookhall, Consett DH8 7ND, UK; tel: +44-1207-505131; fax:+44-1207-590-467 T Targor GmbH, RheinstraEe 4 G, D-55116 Mainz, Germany; tel: + 4 9 - 6 1 3 1 2070; fax: +49-6131-207-555 TEA Electro Conductive Products, PO Box 56, Rochdale 0L12 7EY, UK; tel: +441706-47718; fax:+44-1706-46170 Technical Fibre Products, Burneside Mills, Kendal, Cumbria LA9 6PZ, UK; tel:+44-1539-818264;fax:+44-1539-733850 Techno-Polymer, Postfach 1250, D-5982 Neuenrade, Germany; tel: +49-23926355; fax: +49-2392-64000 Tecnon Ltd, 12 Calico House, Plantation Wharf, York Place, London SWl 1 3TN; tel:+44-171-924-3955; fax:+44-171-978-5307 Teijin Ltd, 1-6-7, Minami-Honmachi, Chuo-ku, Osaka 541, Japan; tel: +81-6268-2132; fax:+81-6-268-3205 Teknor Apex International, 505 Central Avenue, Pawtucket, RI 0 2 8 6 1 , USA; tel:+1-401-725-8000 Tekuma Kunststoff GmbH, MoUner LandstralSe 75, D-2000 Oststeinbeck, Germany; tel: +49-40-712-0057 Telsonic AG, IndustriestraKe, CH 9552, Bronschhofen, Switzerland; Tel: + 4 1 73-225-353. Tempress Inc, 701 South Orchard, Seattle, WA 98108, USA; tel: +1-206-7621410 Tenax Fibers GmbH & Co KG, D-42097, Wuppertal, Germany; tel: +49-202-322338; fax: +49-202-32-2360 Ter Hell Plastic GmbH, Postfach 11648, D-4690 Heme, Germany; tel: +492323-496-10 Textron Inc, 40 Westminster Street, Providence, RI 0 2 9 0 3 , USA; tel: +1-401421-2800; fax:+1-401-421-2878 Thai Oleochemicals Co Ltd, 87 Yotha Road, Taladnoi, Sampantawong Bangkok 10100, Thailand; tel: +66-2-235-9565; fax: +66-2-235-8448 Thermofil Polymers (UK) Ltd, New Lane, Havant P09 2N0, UK; tel: +44-705486350; fax: +44-705-472388. Ticona GmbH, D 65926, Frankfurt am Main, Germany; tel: +49-69-305-3 73 7; fax:+49-69-305-83194 Tigerwerk Lack u Farbenfabrik GmbH, NegrellistraSe 36, A-4600 Wels, Austria; tel: 43-72-42-400; fax: +43-72-42-54476 TI-K VIV, Desguinlei 214, B-2018 Antwerpen, Belgium. Tintometer Co, Waterloo Road, Salisbury SPl 2JY, UK; tel: +44-1722-327-242; fax:+44-1722-412-322

362


Tioxide International, Lincoln House 13 7-143 Hammersmith Rd, London W14 0OL,UK;tel:+44-20-7331-7746; fax:+44-20-7331-7711 Toho Chemical Industry Co Ltd, No 1-1-5 Shintomi, Nihonbashi, Chuo-ku, Tokyo 104,Japan;tel:+81-3-3555-3731; fax:+81-3-3555-3755 Tonen Chemical Corp, Togeki Building, 4-1-1, Tsukiji, Chuo-ku, Tokyo 104, Japan; tel:+81-3-3542-7361; fax:+81-3-5565-1402 Tool-Temp UK, 60-68 Tanners Drive, Blakelands, Milton Keynes MK14 5BP, UK; tel:+44-908-211718; fax:+44-908-216401. Toray Industries Inc, Toray Building, 2-1, Nihonbashi-Muromachi 2-chome, Chuo-ku, Tokyo 103,Japan; tel:+81-3-3245-5113; fax:+81-3-3245-5459 Toshiba Corp, 1-1-1, Shibaura, Minato-ku, Tokyo 105, Japan; tel; +81-3-3457 2104; fax: +81-3-3456-4776 Tosoh Corp, 1-7-7, Akasaka, Minato-ku, Tokyo 107, Japan; tel: +81-3-35853311; fax:+81-3-3582-7846 TowaChemicalCoLtd,Japan;tel:+81-6-723-5700; fax:+81-6-723-3509 Townsend Chemicals Pty Ltd, 114-126 Dandenong-Frankston Road, Dandenong VIC 3175, Australia; tel: +61-3-9793-6000; fax: +61-3-974-0723 Toyobo Co Ltd, 2-2-8, Dojimahama, Kita-ku, Osaka 530, Japan; tel: +81-6-3483111;fax:+81-6-348-3192 Tramaco GmbH, SiemensstraKe 1-3, D-25421 Pinneburg, Germany; tel: +494101-706-02; fax: +49-4101-706-200 Transpek Industry Ltd, KalahRoad, Atladra, Vadorara 390 012, India; tel: + 9 1 265-335-444; fax: +91-265-334-141 U Ube Europe GmbH, Nylon Resin Department, Germany; tel: +49-211-178-8325; fax:+49-211-361-3297 Ube Industries Inc, 315 E Eisenhower Ste 214, Anne Arbor, MI 48108, USA; tel:+l-313-769-5751 UCB SA, Chemical Sector, Specialities Group, Anderlecht Street 33, B-1620 Drogenbos, Belgium; tel: +32-2-334-5735; fax: +32-2-334-5924 Ulmer Fullstoff Vertrieb GmbH, Postfach 1240, D-7906 Blaustein, Germany; tel:+49-7304-8171; fax:+49-7304-8176 UMC International pic, Mayflower Close, Chandlers Ford Industrial Estate, EastleighS05 3AR, UK; tel:+44-703-269866; fax:+44-703-253198 Unichem Products, Divn of Colorite Polymers, 101 Railroad Avenue, Ridgefield, NJ07657,USA;tel:+1-201-941-2900; fax:+1-201-941-0308 Unichema Germany, Postfach 10 09 63, D-46429 Emmerich, Germany; tel:+49-2822-720; fax:+49-2822-72276 Unichema International, Postbus 2, 2800 Gouda, The Netherlands; tel: + 3 1 1820-42911;fax:+31-1820-42250 Unichema North America, 4650 South Racine Ave, Chicago, IL 60609, USA; tel:+1-312-376-9000; fax:+1-312-376-0095 Union Carbide Corporation, Old Ridgebury Rd, Danbury, CT 06817 USA; tel: + 1 203-794-2382; fax:+1-203-794-3088


363

Unipoly SA, Sherwood House II, 8a Upper High St, Winchester S23 8UT, UK; tel:+44-1962-878117;fax:+44-1962-878102 Uniqema, 30 Queen Anne's Gate, London SWl A 9AB, UK Uniroyal Chemical Co Inc, World Headquarters, Benson Road, Middlebury, CT 06749, USA; tel: +1-203-573-2000; fax: +1-203-573-2489 United Carbon India Ltd, NKM International House, Babubhai M Chinai Marg, Bombay 400 020, India; tel: +91-2021-914; fax: +91-285-0406 United Mineral and Chemical Corp, 1100 Valley Brook Ave, Lyndhurst, NJ 07071-3608, USA; tel: +1-201-507-3300; fax: +1-201-507-1506 Unitika Ltd, 4-1-3, Kita-Kyutaromachi, Chuo-ku, Osaka 5 4 1 , Japan; tel: +81-6281-5695; fax:+81-6-281-5697 US Borax, 26877 Tourney Road, Valencia, CA 91355-1847, USA; tel: +1-805287-5464; fax: +1-805-287-5545 US Gypsum Co, 125 S Franklin Street, Chicago, IL 60606, USA; tel: +1-312606-4018; fax: +1-312-606-4519 Uvalight Technology Ltd, 9th Floor, St. Martins House, Bull Ring, Birmingham B5 5DT, UK; tel: +44-21-643-2463/2472; fax: +44-21-643-3879. UVTEC Inc, 1121 108th Street, Arlington, TX 76011, USA; fax: +1-817-6400133. V Vanetti Colori, Viale Kennedy 856, 1-21050 Marnate (Va), Italy; tel: +39-331365-267;fax:+39-331-365-297 Velsicol Chemical Corp, 10400 W Higgins Road, Suite 600, Roesmont, IL 60018, USA; tel: +1-847-298-9000; fax: +1-847-298-3642 Vetrotex CertainTeed Corp, Fiber Glass Reinforcements, 750 E Swedesford Road, PO Box 860, Valley Forge, PA 19482, USA; tel: +1-215-341-7000; fax: + 1-215-293-1765 Vetrotex International, 767 Quai des Allobroges BP 929, F-73009 Chambery Cedex, France; tel: +33-79-75-5300; fax: +33-79-75-5405 Vinnolit Kunststoff GmbH, Carl-Zeiss-Ring 25, D-85737 Ismaning, Germany; tel: +49-89-96-1030; fax: +49-89-96-103103 Vista Chemical Co, PO Box 19029, Houston, TX 77224, USA; tel: +1-713-5883000; fax:+1-713-588-3119. Vulcan Catalytic Systems, High Point Road, PO Box 855, Portsmouth, RI02 8 71, USA; Tel: +1-401-683-2070; Fax: 1-401- 683-6450.

W Wacker Chemie GmbH, Hanns-Seidel-Platz 4, D-81737 Miinchen, Germany; tel:+49-89-62-7901; fax:+49-89-79-1770 Wayne Machine & Die Co, 100 Furler Street, Totowa, NJ 07512-1896, USA; tel:+1-973-256-7374; fax:+1-973-256-1778 Weko (UK) Ltd, Weko House, 2 Park Road, Kingston-upon-Thames KT2 6AY, UK; teh+44-81-549-8039; fax:+44-81-547-1119.

3 64


Werner & Pfleiderer GmbH, TheodorstraEe 10, D-70469 Stuttgart, Germany; tel:+49-711-8970; fax:+49-711-897-3999 Westdeutsche Ouartzwerke Dr. Muller GmbH, Postfach 680, D-42 70 Dorsten, Germany; tel: +49-2362-200-50; fax: +49-2363-200-599 Whitford Plastics Ltd, Christleton Court, Manor Park, Runcorn, Cheshire WA7 ISU, UK; tel:+44-1928-571-000; fax:+44-1928-571-010 Wilson Color SA, 2 rue Melville Wilson, B-5330 Assesse, Belgium; tel: +32-83660-211; fax:+32-83-660-363 Wilson Colour & Additive Concentrates, 2 Rue de Tlndustrie, Zoning de la Fagne, B-5330 Assesse, Belgium; tel: +32-83-655-021; fax: +32-83-656-005 Windmoller & Holscher, Postfach 1660, 49516 Lengerich, Germany; tel: +495481-14-2929; fax:+49-5481-14-3355 Witco Corporation, One American Lane, Greenwich, CT 06831-2559, USA; tel: +1-203-552-3294; fax: +1-203-552-2886 Wittmann UK; 19 Faraday Court, Park Farm (North) Industrial Estate, Wellingborough NN8 6XY, UK; tel: +44-933-401455; fax: +44-933674116. WIZ Chemicals, Via G Deledda 11, 1-20025 Legnano (Mi), Italy; tel: + 3 9 - 3 3 1 545-654; fax: +39-331-546-900 WLT Ltd, 250 Thornton Road, Bradford BDl 2LB, UK Worlee Chemie GmbH, GrusonstraSe 22, D-22113 Hamburg, Germany; tel: +49-40-733-330; fax: +49-40-733-33296

Z Zeneca Specialties, PO Box 42, Hexagon House, Blackley, Manchester M9 8ZS, UK; tel: +44-161-740-1460; fax: +44-161-795-6005 Zipperling Kessler & Co, PO Box 1464, D-22904 Ahrensburg, Germany; tel: +49-4102-515-10; fax:+49-4102-487-169 Zoltek, Carbon and Graphite Divn, 3101 McKelvey Road, St Louis, MO 63044, USA; tel:+1-314-291-5110; fax:+1-314-291-8536 Zychem Ltd, 72 Grasmere Road, Gatley SK8 4RS, UK; tel: +44-161-428-9102; fax:+44-161-428-3686

Industry associations and federations

The following are associations and federations representing the plastics industry, for commercial and technical interests: Argentina CAIP Camara Argentina de la Industria Plasticoa, Jeronimo Salguero 1 9 3 9 / 4 1 , RA-1425 Buenos Aires Australia The Plastics Industry Association Inc, 4 1 - 4 3 Exhibition Street, Melbourne 2000


365

Austria FDCIO: Fachverband der Chemischen Industrie Osterreichs, Wiener HaupstraKe 63, POBox 325, A-1045 Vienna Belgium Belgian Plastics and Rubber Institute, c/o ABIC/BVR, Sqare Marie-Louise 49, B-1040Brussels;tel:+32-2-238-9778; fax:+32-2-231-1301. Fechiplast: Federation des Industries Chimiques de Beige, Square Marie-Louise 49, B-1040 Brussels Brazil ABIPLAST: Associacao Brasileira das Industrias Plasticos, Avenida Paulista 2 4 3 9 - 8 andar, 01311 Sao Paolo SP Canada SPI: Society of the Plastics Industry of Canada, 1262 Don Mills Road, Suite 104, Don Mills, Ontario M3B 2 W7 Chile ASIPLA: Asociacion de Industriales del Plasticos de Chile, Avda Pefro de Valdivia 1481, Casilla (POBox) 1460, Correo 2 1 , Santiago Czech Republic Polymer Institute Brno, Tkalcovska 2, 656 49 Brno; tel: +42-5-45-321-249; + 4 2 - 5 4 5 2 1 1 141 Denmark Plastindustrien i Danmark, Radhuspladsen 5 5, DK-15 50, Copenhagen V Finland FIPIF: FinskaPlastindustriforbundet, Mariankatu 26 B 9, SF-00170 Helsinki France SPMP: Syndicat Professionel des Producteurs de Matieres Plastiques, Tour Aurore, Cedex 5, F-92080 Paris-La Defense Franplast: Federation de la Plasturgie, 65 ruedeProny,F-75854Paris, Cedex 17 Symacap: Syndicat des Constructeurs Francais de Material pour le Caoutchouc et les Matieres Plastiques, 39/41 rue Louis Blanc, Cedex 72, F-92038 Paris-La Defense Germany AVK: Arbeitsgemeinschaft Verstarkte Kunststoffe eV, Am Hauptbahnhof 12, D-6000 Frankfurt/M. 1 AgPU: Arbeitsgemeinschaft PVC und Umwelt eV, Adenauerallee 45, D-53129 Bonn 1 DKI: Deutsches Kunststoff-Institut, SchloBgartenstrafie 6R, D-64289 Darmstadt

366


EWVK: Entwicklungsgesellschaft fur die Wiederverwertung von Kunststoffen mbH, RheingaustraEe 190, D-6200 Wiesbaden GKV: Gesamtverband Kunststoffverarbeitende Industrie eV, Am Hauptbahnhof 12, D-60329 Frankfurt/Main 1 Institut fiir Kunststoffverarbeitung an der RWTH Aachen, Pontstrafie 49, D-5100 Aachen VKE: Verband Kunststofferzeugende Industrie eV, KarlstraEe 2 1 , D-60329 Frankfurt/Main 1 VDI-Gesellschaft Kunststofftechnik, PO Box 10113 9, D-4000 Dusseldorf 1 VDMA-Fachgemeinschaft Gummi- und Kunststoffmaschinen, Lyoner StraSe 18, D-6000 Frankfurt/Main Hungary Association of the Hungarian Plastics Industry, PO Box 40, 1406 Budapest 76 India AIPMA: All-India Plastics Manufacturers Association, Jehangir Building, 3rd Floor, 133 Mahatma Ghandi Road, Bombay 400 023 Ireland Plastics Industries Association, Confederation House, Kildare Street, Dublin 2 Israel Society of Israeli Plastics and Rubber Industries, 29 Hamered Street, PO Box 50022, Tel Aviv 61500 Italy Assoplast, Via Accademia 33,1-20131 Milan Unionplast, Via Pettiti 216,1-20149 Milan Assocomaplast, Centro Commerciale Milanofiori, Palazzo, F/2, Casella Postale 24, 20090 Assago Japan JPIF: Japan Plastics Industry Federation, Tokyo Club Building, 3-2-6 Kasumigaseki, Chiyoda-ku, Tokyo 100 Japan PVC Association, lino Building, 2-1-1, Uchisaiwai-cho, Chiyoda-ku, Tokyo 100 Korea (Republic) Korea Plastic Industry Cooperative, Korea Plastic Building, No 146-2, Sangrimdong, Choong-ku, Seoul Mexico ANIPAC: Asociacion Nacional de Industrias del Plastico, AC, Sullivan No. 165, A P 4, Mexico City 4, DF


367

The Netherlands NFK: Nederlandse Federatie voor Kunststoffen, Polanerbaan 15, Postbus 344, NL-3440AHWoerden TNO Centre for Polymeric Materials, Schoemakerstraat 97, NL-2 600 JA Delft New Zealand PINZ: New Zealand Manufacturers Federation Inc, Enterprise House, 3-9 Church Street (off Boulcott Street), Wellington 1 Norway Plastindustriforbundet, Parkveien 5, N-0350 Oslo 6 Portugal Associacao Portuguesa Industria Plasticos, rue d'Estefania 32-2, P-1000 Lisbon Romania Societer Comerciala ROMPLAST SA, Str Ziduri Mosi, Nr 23-25, Sector 2, 73342, Bucharest South Africa PES A: Plastics Federation of South Africa, PO Box 1128, Edenvale 1610 Spain ANAIP: Asociacion Espanola de Empresarios de Plasticos, Raimundo Fernandez, Villaverde 57, E-28003 Madrid Sweden Sveriges Plastforbund, Sveavagen 35-3 7, S-11134 Stockholm Foreningen Sveriges Plastfabrikanter, Torsgatan 2, S-111 85 Stockholm Switzerland ASKI: Arbeitsgemeinschaft der Schweizerischen Kunststoffindustri, NordstraBe 15, CH-8006 Zurich KVS: Kunststoff-Verband Schweiz, Schachenallee 29, CH-5000 Aarau VKI: Verband Kunststoffindustri der Schweiz, TurnerstraSe 10, CH-8033 Zurich Taiwan Taiwan Plastics Industry Association, 7th Floor, 162 Chang An East Road, Sec. 2 Taipei 104 Turkey State Statistics Institute, Necatibey Cad No 114, Ankara United Kingdom British Plastics Federation, 6 Bath Place, Rivington Street, London EC2 A 3JE Institute of Materials, 1 Carlton House Terrace, London SWIW 5DB

368


United States of America International Institute of Synthetic Rubber Producers Inc - IISRP, 2077 South Gessner Rd, Suite 133, Houston, TX 77063-1123; tel: +1-713-783-7511; fax:+1-713-783-7253 Plastics Institute of America Inc, 2 7 7 Fairfield Road, Fairfield, NJ 07004-1932 SPI: Society of the Plastics Industry Inc, 12 75 K Street, N W, Suite 400, Washington, DC 20005 The Society of the Plastics Industry Inc, 355 Lexington Avenue, New York, NY 10017 European Union Association of Plastics Manufacturers in Europe - APME, Avenue E Van Nieuwenhuyse 4, B-1160 Brussels, Belgium BSEF: Bromine Science and Environmental Forum, 118 Av de Cortenbergh, 1000 Brussels, Belgium; tel: +32-2-733-93 70; fax: +32-2-735-6063 CEFIC: European Chemical Industry Council, Av E Nieuwenhuyse 4, Box 1, B-1160 Brussels, Belgium ECETOC: European Centre for Ecotoxicology and and Toxicology of Chemicals, Ave E Van Nieuwenhuyse 4, bte 6, B-1160 Brussels, Belgium ECVM: European Council of Vinyl Manufacturers, Ave E Van Nieuwenhuyse 4, Box 4, B-1160 Brussels, Belgium; tel: +32-2-675-2971; fax: +32-2-6753935 EUROMAP: European Committee of Machinery Manufacturers for the Plastics and Rubber Industries, Technical Committee; c/o VDMA e.V, Fachgemeinschaft Gummi- und Kunststoffmaschinen, PO Box 71 08 64, D-60498 Frankfurt, Germany European Centre for Plastics in the Environment, Ave E van Nieuwenhuyse 4, Box 5, B-1160 Brussels, Belgium ECPI: European Council for Plasticizers and Intermediates, Av E van Nieuwenhuyse 4, bte 2, B-1160 Brussels, Belgium; tel: +32-2-676-7260; fax:+32-2-676-7216 EFCTC: European Fluorocarbon Technical Committee, c/o CEFIC, Av E van Nieuwenhuyse 4, bte 1, B-1160 Brussels, Belgium; tel: +32-2-676-7211; fax:+32-2-676-7301 EuPC: European Plastics Converters Association, Ave de Cortenburgh 66, B-1000 Brussels, Belgium; tel: +32-2-732-4124; fax: +32-2-732-4218 AFPE: European Glass Fibre Producers' Assocation, 89 Avenue Louise, B-1050, Brussels, Belgium European Isocyanate Producers' Association, Ave E van Nieuwenhuyse 4, Box 1, B-1160 Brussels, Belgium ES-VOC-CG: European Solvents VOC Coordination Group, 4 Avenue Van Nieuwenhuyse, 1160 Brussels, Belgium; tel: +32-2-676-7264; fax: +322-676-7301 Eutraplast: Committee of Plastics Converters' Associations in W Europe, Rue Souveraine 97, B-1050 Brussels, Belgium

DATA SHEETS The following charts present basic data on different types of additive, based on data from manufacturers. Where possible, manufacturers' data have been harmonized, but there will be cases where data are not comparable. Data are presented as a guide to the general properties and applications of each material: specific points should be checked with potential suppliers. Fillers and extenders

Fillers and extenders

Calcium carbonate Description: Most widely used filler for plastics: forms vary according to geographical source. Surface treatments greatly improve properties and controlled particle size makes functional fillers possible: improved flow properties, low-profile anti-shrinkage, anti-blocking additives; treatment with aluminium trihydroxide (ATH) gives some flame retardancy Property

Typical grades

l^^nit

Chemical analysis

CaCOi

97.9

97.9

97.9

97.9

Specific gravity

g/cm^

2.7

2.7

2.7

2.7

Mohs hardness

3

3

pH value

9.1

8.5

8.5

9.0

2.2

2.2

3.2

2.2

Refractive index Specific surface

m^/g

Abrasion

g/m-

22-23

23

18

25

|im

0.8-20

0.8-2 5

0.8-10

0.8-20

g/lOOg

22

Loose bulk density

kg/m^

5 50-600

Tamped volume

kg/m^

750-800

Whiteness FMY

% % nS/cm

Particle size distr. Oil absorption

Moisture Conductivity

22 1790

1200

600

85

89.4

92.0

84.0

100

160

160

110

© 2001 Elsevier Science Ltd

3 70



Calcium carbonate Description: Most widely used filler for plastics: forms vary according to geographical source. Surface treatments greatly improve properties and controlled particle size makes functional fillers possible: improved flow properties, low-profile anti-shrinkage, anti-blocking additives: treatment with aluminium trihydroxide (ATH) gives some flame retardancy Property

Chemical analysis Specific gravity

Typical grades

Unit Vfine

Fine, easy dispense

Surface-coated

Coated easy dispense

CaC03

98

98

98

98

g/cm^

2.7

2.7

2.7

2.7

Mohs hardness

3

3

3

3

Refractive index

1.59

1.59

1.59

1.59

9

9

9

9

(im

1.6

2.7

2.4

5.5

g/lOOg

17

16

14

13

1.0

1.3

1.2

1.5

93.5

90.5

83

88

0.3

0.2

0.2

0.2

pH value Specific surface

m^/g

Abrasion

g/m^

Av. particle size Oil absorption Loose bulk density

kg/m^

Packed bulk density

g/cm^

Whiteness Ry Moisture Conductivity

% % }iS/cm

© 2001 Elsevier Science Ltd |

Datasheets

371


Calcium carbonate Description: Most widely used filler for plastics: forms vary according to geographical source. Surface treatments greatly improve properties and controlled particle size makes functional fillers possible: improved flow properties, low-profile anti-shrinkage, anti-blocking additives; treatment with aluminium trihydroxide (ATH) gives some flame retardancy Property

Chemical analysis Specific gravity

Typical grades

Unit V fine/surface c

Ultrafine/surface c

Ultrafine/surface c

CaCOs

98

98

98

g/cm^

2.7

2.7

2.7

Mohs hardness

3

3

3

Refractive index

1.59

1.59

1.59

9

9

9

l^m

1.4

0.85

1.0

16

17

18

1.0

0.8

0.8

88

94

89

0.2

0.35

0.3

pH value Specific surface

m^/g

Abrasion

g/m^

Av. particle size Oil absorption

g/lOOg

Loose bulk density

Kg/m^

Packed bulk density

g/cm^

Whiteness Ry Moisture Conductivity

% % )iS/cm


1

i 11



China clay Description: Water-washed china clay dehydrated to produce a very white extender, with high opacity Chemical analysis: Si02 = 55.3, AI2O3 = 42.6, Fe203 = 0.33, TiO- = 0.35,K2O = 0.70, Na20 - 0.08, CaO = 0.03, MgO - 0.07, P2O5 = 0.24, Mn02 0.01 Property

Unit

Specific gravity

g/ml

pH value

Typical grades 2.6

2.6

6-7

6-7

Specific surface

m^/g

4.0

4.2

Av. particle size

}xm

4.7

4.3

Sedimentation analysis: 10-40 j^m

% % %

12

10

80

82

8

8

g/lOOg

62

63

2-10 |im < 2 |im Oil absorption Loose bulk density Whiteness Ry Loss on ignition

g/ml

0.3

0.3

%

90.2

90.7

0.12

0.12

1

© 2001 Elsevier Science Ltd |

Datasheets

373


Magnesium silicate Description: Extra-high-purity, high-whiteness platelet Chemical analysis: Si02 = 63.2, MgO = 3 1 . 7 , AI2O3 = 0.17, Fe203 = 0.03, CaO 0.01 1 Property Specific gravity

Unit g/ml

Typical grades 2.75

2.75

2.7

2.3

2.1

4.3

2.7

1 pH value Specific surface

m^/g

Av. particle size

)im

j Sedimentation analysis: 10-40 îm 2-10 j^m < 2 [im

Oil absorption Tamped bulk density Whiteness Ry

% % %

41

31

74

60-55

59

69

26

5-2

58

48

41-33

g/lOOg g/ml

0.35

0.35

0.58

0.68-0.99

%

92

94

94

92

4.8

4.8

4.8

4.8 < 0.3

Loss on ignition Moisture

7-14 40-43

%

Op-l

2.80

2.30

Refractive index

at25°C

1.55-1.566

1.541

UV transmission

at25°C

opaque

Volume resistivity

Qcm

17.7-10.4

Dielectric constant

^cm

6.5-7.0

Coeff. therm, exp.

Alkalinity Solvent resistance Alkali resistance Acid resistance

6.0-8.1

Na20 %

0.3

0.4

% % %

good

good

good

good

exc. hydrofluoric

exc. hydrofluoric © 2001 Elsevier Science Ltd |

Datasheets

387

Reinforcements

Glass fibre Description: The main fibrous reinforcement for thermoplastics and thermosets, giving high tensile strength but low stiffness: sizing/coupling agents give better bond: very short fibres used for thermoplastics (injection moulded); longer fibres giving higher reinforcement now becoming accepted; long, continuous, mat or woven fibres used for thermosets Property

Tensile strength

Typical grades

Unit E-glass

R-glass

3331

3330

3185

3240

MNm^

I -virgin fibre 23°C - virgin fibre 100°C

5320

5280

Modulus of elasticity

GNm^

72.5

72.5

Density

gcm^

2.52-2.62

2.70-2.72

1.556

1.576

-virgin fibre 196°C

Refractive index Coeff. linear thermal expansion

1/°C

5.0x10-^

5.9x10-^

Diel. constant: - 60 Hz

23°C

6.4

7.1

6.2

7.0

23°C

0.003

0.004

0.004

0.003

- 1 0 ^ Hz Loss tangent 60 Hz - 1 0 ^ Hz Volume resistivity: - 5 0 0 V DC Dielectric strength (kV mm)

^/cm23°C

10^4

10^4

9.80

9.96


388


Reinforcements

Carbon fibre Description: High performance/high stiffness: used with high performance engineering thermoplastics (injection moulding), but mainly with thermosetting resins, as long/continuous fibre reinforcement, often woven or with other fibres Property

Density

Unit

Typical grades

g/cm^

HT

IM

HM

UHM

1.8

1.8

1.8

2.0

Tensile strength

MPa

3500

5300

3500

2000

Flexural modulus

GPa

160-270

270-325

325-440

440+

Specific modulus

Mm

90-150

150-180

180-240

200+

© 2 001 Elsevier Science Ltd

Reinforcements

Aramid fibre Description: High performance fibre, high stiffness, low weight: used esp. in composites with other fibres: also developed as chopped fibre, powder additive or masterbatch for improved lubrication/wear resistance in injection moulded engineering thermoplastics Property

Typical grades

Unit LM

HM

UHM

g/cm^

1.45

1.45

1.47

Tensile strength

MPa

3600

3100

3400

Flexural modulus

GPa

60

120

180

Specific modulus

Mm

40

80

120

Density


Datasheets

389

Reinforcements

Glass spheres (solid) Description: Solid soda-lime glass: used as reinforcing filler in thermoplastic and thermosetting moulding compounds: improves stiffness, heat distortion, shrinkage; can also improve flow properties: grades differentiated by size (90% beads of designated diameter): other size ranges are produced Property

Unit

Typical grades 3-80 îm

0.5-19.3 |im

2.45 2.55

Specific gravity Hardness

0.8-70 îm

Mohs

6 1.51-1.52

Refractive index Av diameter

\xm

27-36

12-26

3.5-7.0

Surface area

m^/cm^

0.40-0.80

1.05-1.75

1.75-3.30

Oil absorption

g/lOOg

17

/K

7.75 10-^

Tensile modulus

N/mm^

6.89 10^

Flexural modulus

N/mm^

2.96X

Coeff. thermal exp

0.21

Poisson's ratio Volume resistivity

Gfim

300

Dielectric strength

kV/cm

4500

Dielectric constant

IKHz

7.6

Power factor

0.9 © 2001 Elsevier Science Ltd |

390


Reinforcements

Glass spheres (hollow) Description: Hollow borosihcate glass: white powder, spherical, non-porous; low alkah leach, insoluble in water: hghter weight than solid glass; can be damaged in moulding process, but 1 properties of compound are still useful Property

Unit

Typical grades

1 Chemical analysis: Specific gravity

1.08

Crush strength (% volume loss)

3000 psi lOOOOpsi

neglig. 13%

1 Colour value

90.0 min

Av diameter

8.4

Particle size distr.

Surface area

10% 50% 90%

4.2 8.7 14.0

m^/ml

0.47

pH value

8.3

Conductivity

52

mmoh/cm

Notes: In a variety of thermoplastics, good whiteness/opacity suggests possible use as low-cost pigment extender © 2001 Elsevier Science Ltd

Reinforcements

Thermoplastic spheres (expandable) Description: Gas-filled thermoplastic spheres, expanding at processing temperature: can form useful syntactic foam structure Approx. solid content (%) WU 65

67

65

63

Number average

5-8

5-8

5-8

3-5

Weight average

10-16

10-16

10-16

6-9

°C

81-96

90-95

99-104

99-104

Particle size average

mm

Thermomechanical Tstart

T

°C

122-132

132-140

142-150

136-144

TMA density

kg/m^

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