Polyvinyl Alcohol: Materials, Processing and Applications (Rapra Review Reports)

Report 192 ISSN: 0889-3144 Polyvinyl Alcohol: Materials, Processing and Applications E. Ogur Volume 16, Number 12, 2...

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Report 192

ISSN: 0889-3144

Polyvinyl Alcohol: Materials, Processing and Applications

E. Ogur

Volume 16, Number 12, 2005

Expert overviews covering the science and technology of rubber and plastics

RAPRA REVIEW REPORTS VOLUME 16 Series Editor Mrs. F. Gardiner, Smithers Rapra Technology Rapra Review Reports comprise a unique source of polymer-related information with useful overviews accompanied by abstracts from hundreds of relevant documents. A Rapra Review Report is an excellent starting point to improve subject knowledge in key areas. Subscribers to this series build up a bank of information over each year, forming a small library at a very reasonable price. This series would be an asset to corporate libraries, academic institutions and research associations with an interest in polymer science. Twelve reports are published in each volume and these can be purchased individually or on a subscription basis. Format: Soft-backed, 297 x 210 mm, ISSN: 0889-3144 Order individual published Rapra Review Reports (see the following pages for a list of available titles), or purchase a subscription to Volume 16 (12 issues).

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RAPRA REVIEW REPORTS A Rapra Review Report comprises three sections, as follows: 1. A commissioned expert review, discussing a key topic of current interest, and referring to the References and Abstracts section. Reference numbers in brackets refer to item numbers from the References and Abstracts section. Where it has been necessary for completeness to cite sources outside the scope of the Rapra Abstracts database, these are listed at the end of the review, and cited in the text as a.1, a.2, etc. 2. A comprehensive References and Abstracts section, resulting from a search of the Rapra Polymer Library database. The format of the abstracts is outlined in the sample record below. 3. An index to the References and Abstracts section, derived from the indexing terms which are added to the abstracts records on the database to aid retrieval.

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Item 1 Macromolecules 33, No.6, 21st March 2000, p.2171-83 EFFECT OF THERMAL HISTORY ON THE RHEOLOGICAL BEHAVIOR OF THERMOPLASTIC POLYURETHANES Pil Joong Yoon; Chang Dae Han Akron,University The effect of thermal history on the rheological behaviour of ester- and etherbased commercial thermoplastic PUs (Estane 5701, 5707 and 5714 from B.F.Goodrich) was investigated. It was found that the injection moulding temp. used for specimen preparation had a marked effect on the variations of dynamic storage and loss moduli of specimens with time observed during isothermal annealing. Analysis of FTIR spectra indicated that variations in hydrogen bonding with time during isothermal annealing very much resembled variations of dynamic storage modulus with time during isothermal annealing. Isochronal dynamic temp. sweep experiments indicated that the thermoplastic PUs exhibited a hysteresis effect in the heating and cooling processes. It was concluded that the microphase separation transition or order-disorder transition in thermoplastic PUs could not be determined from the isochronal dynamic temp. sweep experiment. The plots of log dynamic storage modulus versus log loss modulus varied with temp. over the entire range of temps. (110-190C) investigated. 57 refs. GOODRICH B.F. USA

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Abstract

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Accession no.771897

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Previous Titles Still Available Volume 1

Report 34

Extrusion of Rubber, J.G.A. Lovegrove, Nova Petrochemicals Inc.

Report 1

Conductive Polymers, W.J. Feast

Report 35

Report 2

Medical, Surgical and Pharmaceutical Applications of Polymers, D.F. Williams

Polymers in Household Electrical Goods, D.Alvey, Hotpoint Ltd.

Report 36

Report 3

Advanced Composites, D.K. Thomas, RAE, Farnborough.

Developments in Additives to Meet Health and Environmental Concerns, M.J. Forrest, Rapra Technology Ltd.

Report 4

Liquid Crystal Polymers, M.K. Cox, ICI, Wilton.

Report 5

CAD/CAM in the Polymer Industry, N.W. Sandland and M.J. Sebborn, Cambridge Applied Technology.

Report 8

Engineering Thermoplastics, I.T. Barrie, Consultant.

Report 10

Reinforced Reaction Injection Moulding, P.D. Armitage, P.D. Coates and A.F. Johnson

Volume 4 Report 37

Polymers in Aerospace Applications, W.W. Wright, University of Surrey.

Report 38

Epoxy Resins, K.A. Hodd

Report 39

Polymers in Chemically Resistant Applications, D. Cattell, Cattell Consultancy Services.

Report 40

Internal Mixing of Rubber, J.C. Lupton

Report 41

Failure of Plastics, S. Turner, Queen Mary College.

Report 42

Polycarbonates, R. Pakull, U. Grigo, D. Freitag, Bayer AG.

Volume 2

Report 43

Polymeric Materials from Renewable Resources, J.M. Methven, UMIST.

Report 13

Injection Moulding of Engineering Thermoplastics, A.F. Whelan, London School of Polymer Technology.

Report 44

Flammability and Flame Retardants in Plastics, J. Green, FMC Corp.

Report 14

Polymers and Their Uses in the Sports and Leisure Industries, A.L. Cox and R.P. Brown, Rapra Technology Ltd.

Report 45

Composites - Tooling and Component Processing, N.G. Brain, Tooltex.

Report 15

Polyurethane, Materials, Processing and Applications, G. Woods, Consultant.

Report 46

Quality Today in Polymer Processing, S.H. Coulson, J.A. Cousans, Exxon Chemical International Marketing.

Report 16

Polyetheretherketone, D.J. Kemmish, ICI, Wilton.

Report 47

Chemical Analysis of Polymers, G. Lawson, Leicester Polytechnic.

Report 17

Extrusion, G.M. Gale, Rapra Technology Ltd.

Report 48

Plastics in Building, C.M.A. Johansson

Report 18

Agricultural and Horticultural Applications of Polymers, J.C. Garnaud, International Committee for Plastics in Agriculture.

Volume 5

Report 11

Communications Applications of Polymers, R. Spratling, British Telecom.

Report 12

Process Control in the Plastics Industry, R.F. Evans, Engelmann & Buckham Ancillaries.

Report 19

Recycling and Disposal of Plastics Packaging, R.C. Fox, Plas/Tech Ltd.

Report 49

Blends and Alloys of Engineering Thermoplastics, H.T. van de Grampel, General Electric Plastics BV.

Report 20

Pultrusion, L. Hollaway, University of Surrey.

Report 50

Report 21

Materials Handling in the Polymer Industry, H. Hardy, Chronos Richardson Ltd.

Automotive Applications of Polymers II, A.N.A. Elliott, Consultant.

Report 51

Biomedical Applications of Polymers, C.G. Gebelein, Youngstown State University / Florida Atlantic University.

Report 52

Polymer Supported Chemical Reactions, P. Hodge, University of Manchester.

Report 53

Weathering of Polymers, S.M. Halliwell, Building Research Establishment.

Report 54

Health and Safety in the Rubber Industry, A.R. Nutt, Arnold Nutt & Co. and J. Wade.

Report 55

Computer Modelling of Polymer Processing, E. Andreassen, Å. Larsen and E.L. Hinrichsen, Senter for Industriforskning, Norway.

Report 22

Electronics Applications of Polymers, M.T.Goosey, Plessey Research (Caswell) Ltd.

Report 23

Offshore Applications of Polymers, J.W.Brockbank, Avon Industrial Polymers Ltd.

Report 24

Recent Developments in Materials for Food Packaging, R.A. Roberts, Pira Packaging Division.

Volume 3 Report 25

Foams and Blowing Agents, J.M. Methven, Cellcom Technology Associates.

Report 26

Polymers and Structural Composites in Civil Engineering, L. Hollaway, University of Surrey.

Report 56

Plastics in High Temperature Applications, J. Maxwell, Consultant.

Report 27

Injection Moulding of Rubber, M.A. Wheelans, Consultant.

Report 57

Joining of Plastics, K.W. Allen, City University.

Report 58

Physical Testing of Rubber, R.P. Brown, Rapra Technology Ltd.

Report 59

Polyimides - Materials, Processing and Applications, A.J. Kirby, Du Pont (U.K.) Ltd.

Report 60

Physical Testing of Thermoplastics, S.W. Hawley, Rapra Technology Ltd.

Report 28

Adhesives for Structural and Engineering Applications, C. O’Reilly, Loctite (Ireland) Ltd.

Report 29

Polymers in Marine Applications, C.F.Britton, Corrosion Monitoring Consultancy.

Report 30

Non-destructive Testing of Polymers, W.N. Reynolds, National NDT Centre, Harwell.

Report 31

Silicone Rubbers, B.R. Trego and H.W.Winnan, Dow Corning Ltd.

Report 32

Fluoroelastomers - Properties and Applications, D. Cook and M. Lynn, 3M United Kingdom Plc and 3M Belgium SA.

Report 33

Polyamides, R.S. Williams and T. Daniels, T & N Technology Ltd. and BIP Chemicals Ltd.

Volume 6 Report 61

Food Contact Polymeric Materials, J.A. Sidwell, Rapra Technology Ltd.

Report 62

Coextrusion, D. Djordjevic, Klöckner ER-WE-PA GmbH.

Report 63

Conductive Polymers II, R.H. Friend, University of Cambridge, Cavendish Laboratory.

Report 64

Designing with Plastics, P.R. Lewis, The Open University.

Report 90

Rubber Mixing, P.R. Wood.

Report 65

Decorating and Coating of Plastics, P.J. Robinson, International Automotive Design.

Report 91

Recent Developments in Epoxy Resins, I. Hamerton, University of Surrey.

Report 66

Reinforced Thermoplastics - Composition, Processing and Applications, P.G. Kelleher, New Jersey Polymer Extension Center at Stevens Institute of Technology.

Report 92

Continuous Vulcanisation of Elastomer Profiles, A. Hill, Meteor Gummiwerke.

Report 67

Plastics in Thermal and Acoustic Building Insulation, V.L. Kefford, MRM Engineering Consultancy.

Report 93

Advances in Thermoforming, J.L. Throne, Sherwood Technologies Inc.

Report 68

Cure Assessment by Physical and Chemical Techniques, B.G. Willoughby, Rapra Technology Ltd.

Report 94

Compressive Behaviour of Composites, C. Soutis, Imperial College of Science, Technology and Medicine.

Report 69

Toxicity of Plastics and Rubber in Fire, P.J. Fardell, Building Research Establishment, Fire Research Station.

Report 95

Thermal Analysis of Polymers, M. P. Sepe, Dickten & Masch Manufacturing Co.

Report 70

Acrylonitrile-Butadiene-Styrene Polymers, M.E. Adams, D.J. Buckley, R.E. Colborn, W.P. England and D.N. Schissel, General Electric Corporate Research and Development Center.

Report 96

Polymeric Seals and Sealing Technology, J.A. Hickman, St Clair (Polymers) Ltd.

Report 71

Rotational Moulding, R.J. Crawford, The Queen’s University of Belfast.

Report 72

Advances in Injection Moulding, C.A. Maier, Econology Ltd.

Volume 7 Report 73

Reactive Processing of Polymers, M.W.R. Brown, P.D. Coates and A.F. Johnson, IRC in Polymer Science and Technology, University of Bradford.

Volume 9 Report 97

Rubber Compounding Ingredients - Need, Theory and Innovation, Part II: Processing, Bonding, Fire Retardants, C. Hepburn, University of Ulster.

Report 98

Advances in Biodegradable Polymers, G.F. Moore & S.M. Saunders, Rapra Technology Ltd.

Report 99

Recycling of Rubber, H.J. Manuel and W. Dierkes, Vredestein Rubber Recycling B.V.

Report 100

Photoinitiated Polymerisation - Theory and Applications, J.P. Fouassier, Ecole Nationale Supérieure de Chimie, Mulhouse.

Report 74

Speciality Rubbers, J.A. Brydson.

Report 75

Plastics and the Environment, I. Boustead, Boustead Consulting Ltd.

Report 101

Solvent-Free Adhesives, T.E. Rolando, H.B. Fuller Company.

Report 76

Polymeric Precursors for Ceramic Materials, R.C.P. Cubbon.

Report 102

Plastics in Pressure Pipes, T. Stafford, Rapra Technology Ltd.

Report 77

Advances in Tyre Mechanics, R.A. Ridha, M. Theves, Goodyear Technical Center.

Report 103

Gas Assisted Moulding, T.C. Pearson, Gas Injection Ltd.

Report 104

Plastics Profile Extrusion, R.J. Kent, Tangram Technology Ltd.

Report 105

Rubber Extrusion Theory and Development, B.G. Crowther.

Report 106

Properties and Applications of Elastomeric Polysulfides, T.C.P. Lee, Oxford Brookes University.

Report 107

High Performance Polymer Fibres, P.R. Lewis, The Open University.

Report 108

Chemical Characterisation of Polyurethanes, M.J. Forrest, Rapra Technology Ltd.

Report 78

PVC - Compounds, Processing and Applications, J.Leadbitter, J.A. Day, J.L. Ryan, Hydro Polymers Ltd.

Report 79

Rubber Compounding Ingredients - Need, Theory and Innovation, Part I: Vulcanising Systems, Antidegradants and Particulate Fillers for General Purpose Rubbers, C. Hepburn, University of Ulster.

Report 80

Anti-Corrosion Polymers: PEEK, PEKK and Other Polyaryls, G. Pritchard, Kingston University.

Report 81

Thermoplastic Elastomers - Properties and Applications, J.A. Brydson.

Report 82

Advances in Blow Moulding Process Optimization, Andres Garcia-Rejon,Industrial Materials Institute, National Research Council Canada.

Report 83

Report 84

Molecular Weight Characterisation of Synthetic Polymers, S.R. Holding and E. Meehan, Rapra Technology Ltd. and Polymer Laboratories Ltd.

Volume 10 Report 109

Rubber Injection Moulding - A Practical Guide, J.A. Lindsay.

Report 110

Long-Term and Accelerated Ageing Tests on Rubbers, R.P. Brown, M.J. Forrest and G. Soulagnet, Rapra Technology Ltd.

Report 111

Polymer Product Failure, P.R. Lewis, The Open University.

Rheology and its Role in Plastics Processing, P. Prentice, The Nottingham Trent University.

Volume 8

Report 112

Ring Opening Polymerisation, N. Spassky, Université Pierre et Marie Curie.

Polystyrene - Synthesis, Production and Applications, J.R. Wünsch, BASF AG.

Report 113

Report 86

High Performance Engineering Plastics, D.J. Kemmish, Victrex Ltd.

Rubber-Modified Thermoplastics, H. Keskkula, University of Texas at Austin.

Report 114

Report 87

Rubber to Metal Bonding, B.G. Crowther, Rapra Technology Ltd.

Developments in Polyacetylene - Nanopolyacetylene, V.M. Kobryanskii, Russian Academy of Sciences.

Report 115

Report 88

Plasticisers - Selection, Applications and Implications, A.S. Wilson.

Metallocene-Catalysed Polymerisation, W. Kaminsky, University of Hamburg.

Report 116

Report 89

Polymer Membranes - Materials, Structures and Separation Performance, T. deV. Naylor, The Smart Chemical Company.

Compounding in Co-rotating Twin-Screw Extruders, Y. Wang, Tunghai University.

Report 117

Rapid Prototyping, Tooling and Manufacturing, R.J.M. Hague and P.E. Reeves, Edward Mackenzie Consulting.

Report 85

Report 118

Liquid Crystal Polymers - Synthesis, Properties and Applications, D. Coates, CRL Ltd.

Report 119

Rubbers in Contact with Food, M.J. Forrest and J.A. Sidwell, Rapra Technology Ltd.

Report 120

Electronics Applications of Polymers II, M.T. Goosey, Shipley Ronal.


Polyamides as Engineering Thermoplastic Materials, I.B. Page, BIP Ltd.

Report 122

Flexible Packaging - Adhesives, Coatings and Processes, T.E. Rolando, H.B. Fuller Company.

Report 123

Polymer Blends, L.A. Utracki, National Research Council Canada.

Report 124

Sorting of Waste Plastics for Recycling, R.D. Pascoe, University of Exeter.

Report 125

Structural Studies of Polymers by Solution NMR, H.N. Cheng, Hercules Incorporated.


Multi-Material Injection Moulding, V. Goodship and J.C. Love, The University of Warwick.

Report 146

In-Mould Decoration of Plastics, J.C. Love and V. Goodship, The University of Warwick.

Report 147

Rubber Product Failure, Roger P. Brown.

Report 148

Plastics Waste – Feedstock Recycling, Chemical Recycling and Incineration, A. Tukker, TNO.

Report 149

Analysis of Plastics, Martin J. Forrest, Rapra Technology Ltd.

Report 150

Mould Sticking, Fouling and Cleaning, D.E. Packham, Materials Research Centre, University of Bath.

Report 151

Rigid Plastics Packaging - Materials, Processes and Applications, F. Hannay, Nampak Group Research & Development.

Report 152

Natural and Wood Fibre Reinforcement in Polymers, A.K. Bledzki, V.E. Sperber and O. Faruk, University of Kassel.

Report 153

Polymers in Telecommunication Devices, G.H. Cross, University of Durham.

Report 154

Polymers in Building and Construction, S.M. Halliwell, BRE.

Report 126

Composites for Automotive Applications, C.D. Rudd, University of Nottingham.

Report 127

Polymers in Medical Applications, B.J. Lambert and F.-W. Tang, Guidant Corp., and W.J. Rogers, Consultant.

Report 155

Styrenic Copolymers, Andreas Chrisochoou and Daniel Dufour, Bayer AG.

Report 128

Solid State NMR of Polymers, P.A. Mirau, Lucent Technologies.

Report 156

Life Cycle Assessment and Environmental Impact of Polymeric Products, T.J. O’Neill, Polymeron Consultancy Network.

Report 129

Failure of Polymer Products Due to Photo-oxidation, D.C. Wright.

Report 130

Failure of Polymer Products Due to Chemical Attack, D.C. Wright.

Report 131 Report 132

Failure of Polymer Products Due to Thermo-oxidation, D.C. Wright. Stabilisers for Polyolefins, C. Kröhnke and F. Werner, Clariant Huningue SA.

Volume 12


Developments in Colorants for Plastics, Ian N. Christensen.

Report 158

Geosynthetics, David I. Cook.

Report 159

Biopolymers, R.M. Johnson, L.Y. Mwaikambo and N. Tucker, Warwick Manufacturing Group.

Report 160

Emulsion Polymerisation and Applications of Latex, Christopher D. Anderson and Eric S. Daniels, Emulsion Polymers Institute.

Report 161

Report 133

Advances in Automation for Plastics Injection Moulding, J. Mallon, Yushin Inc.

Emissions from Plastics, C. Henneuse-Boxus and T. Pacary, Certech.

Report 162

Analysis of Thermoset Materials, Precursors and Products, Martin J. Forrest, Rapra Technology Ltd.

Report 134

Infrared and Raman Spectroscopy of Polymers, J.L. Koenig, Case Western Reserve University.

Report 163

Polymer/Layered Silicate Nanocomposites, Masami Okamoto, Toyota Technological Institute.

Report 135

Polymers in Sport and Leisure, R.P. Brown.

Report 164

Report 136

Radiation Curing, R.S. Davidson, DavRad Services.

Cure Monitoring for Composites and Adhesives, David R. Mulligan, NPL.

Report 165

Report 137

Silicone Elastomers, P. Jerschow, Wacker-Chemie GmbH.

Polymer Enhancement of Technical Textiles, Roy W. Buckley.

Report 138

Health and Safety in the Rubber Industry, N. Chaiear, Khon Kaen University.

Report 166

Developments in Thermoplastic Elastomers, K.E. Kear

Report 167 Report 139

Rubber Analysis - Polymers, Compounds and Products, M.J. Forrest, Rapra Technology Ltd.

Polyolefin Foams, N.J. Mills, Metallurgy and Materials, University of Birmingham.

Report 168

Report 140

Tyre Compounding for Improved Performance, M.S. Evans, Kumho European Technical Centre.

Plastic Flame Retardants: Technology and Current Developments, J. Innes and A. Innes, Flame Retardants Associates Inc.

Report 141

Particulate Fillers for Polymers, Professor R.N. Rothon, Rothon Consultants and Manchester Metropolitan University.

Report 142

Blowing Agents for Polyurethane Foams, S.N. Singh, Huntsman Polyurethanes.

Report 143

Adhesion and Bonding to Polyolefins, D.M. Brewis and I. Mathieson, Institute of Surface Science & Technology, Loughborough University.

Report 144

Rubber Curing Systems, R.N. Datta, Flexsys BV.


Engineering and Structural Adhesives, David J. Dunn, FLD Enterprises Inc.

Report 170

Polymers in Agriculture and Horticulture, Roger P. Brown.

Report 171

PVC Compounds and Processing, Stuart Patrick.

Report 172

Troubleshooting Injection Moulding, Vanessa Goodship, Warwick Manufacturing Group.

Report 173

Regulation of Food Packaging in Europe and the USA, Derek J. Knight and Lesley A. Creighton, Safepharm Laboratories Ltd.

Report 174

Pharmaceutical Applications of Polymers for Drug Delivery, David Jones, Queen's University, Belfast.

Report 175

Tyre Recycling, Valerie L. Shulman, European Tyre Recycling Association (ETRA).

Report 176

Polymer Processing with Supercritical Fluids, V. Goodship and E.O. Ogur.

Report 177

Bonding Elastomers: A Review of Adhesives & Processes, G. Polaski, J. Means, B. Stull, P. Warren, K. Allen, D. Mowrey and B. Carney.

Report 178

Mixing of Vulcanisable Rubbers and Thermoplastic Elastomers, P.R. Wood.

Report 179

Polymers in Asphalt, H.L. Robinson, Tarmac Ltd, UK.

Report 180

Biocides in Plastics, D. Nichols, Thor Overseas Limited.


New EU Regulation of Chemicals: REACH, D.J. Knight, SafePharm Laboratories Ltd.

Report 182

Food Contact Rubbers 2 - Products, Migration and Regulation, M.J. Forrest.

Report 183

Adhesion to Fluoropolymers, D.M. Brewis and R.H. Dahm, IPTME, Loughborough University.

Report 184

Fluoroplastics, J.G. Drobny.

Report 185

Epoxy Composites: Impact Resistance and Flame Retardancy, Debdatta Ratna.

Report 186

Coatings and Inks for Food Contact Materials, Martin Forrest, Smithers Rapra.

Report 187

Nucleating Agents, Stuart Fairgrieve, SPF Polymer Consultants.

Report 188

Silicone Products for Food Contact Applications, Martin Forrest, Smithers Rapra.

Report 189

Degradation and Stabilisation of Polymers, Stuart Fairgrieve, SPF Polymer Consultants

Report 190

Electrospinning Jon Stanger, New Zealand Institute for Plant and Food Research Nick Tucker, New Zealand Institute for Plant and Food Research Mark Staiger, University of Canterbury, New Zealand


Vannessa Goodship and Daniel Jacobs

ISBN: 978-1-84735-095-4


Contents 1.

Introduction ................................................................................................................................................3

2.

Application Scope ......................................................................................................................................4

3.

Manufacture ...............................................................................................................................................6

4.

Polymer Chemistry.....................................................................................................................................7 4.1

Viscosity in Solution ........................................................................................................................7

5.

Water Solubility ........................................................................................................................................8

6.

PVAL Film Properties ...............................................................................................................................9 6.1 Barrier Proporties .................................................................................................................................9 6.2 Other Film Properties .........................................................................................................................10 6.2.1

Mechanical Properties .......................................................................................................10

6.2.2

Plasticiser Effects ..............................................................................................................10

6.2.3

Oil and Solvent Resistance ...............................................................................................10

6.2.4

Water Sensitivity and Hygroscopy ...................................................................................10

6.2.5

Adhesion Characteristics...................................................................................................10

6.2.6

Antistatic ...........................................................................................................................10

7.

Solution Processing ..................................................................................................................................10

8.

Melt Processing ........................................................................................................................................11

9.

8.1

Extrusion ........................................................................................................................................12

8.2

Injection Moulding ........................................................................................................................12

8.3

Film Moulding ...............................................................................................................................12

8.4

Blow Moulding ..............................................................................................................................13

Packaging .................................................................................................................................................13 9.1

Active Packaging ...........................................................................................................................13

10. PVAL in Medicine: Hydrogels ................................................................................................................13 11. Biopolymers .............................................................................................................................................14 12. Blends .......................................................................................................................................................15 13. Blends of PVAL .......................................................................................................................................15 13.1 PVAL-Starch Blends .....................................................................................................................15 13.2 Other Blends ..................................................................................................................................16 13.2.1 PVAL/Gelatin Blends .......................................................................................................16

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14. Degradability ............................................................................................................................................17 14.1 Biodegradable Plastics ...................................................................................................................18 14.2 Oil-Based Naturally Degradable Polymers....................................................................................18 14.3 Photo-degradable Plastics ..............................................................................................................18 15. Plastics and Biodegradable Plastics Disposal ..........................................................................................19 15.1 Composting ....................................................................................................................................20 15.2 Incineration ....................................................................................................................................21 15.3 Landfilling ......................................................................................................................................21 16. Conclusion................................................................................................................................................21 References ........................................................................................................................................................22 Abbreviations and Acronyms ..........................................................................................................................22 Subject Index ...................................................................................................................................................00 Company Index ................................................................................................................................................00

Author contact details: Vannessa Goodship WMG, Univeristy of Warwick, Coventry, CV4 7AL Daniel Jacobs WMG, Univeristy of Warwick, Coventry, CV4 7AL

The views and opinions expressed by authors in Rapra Review Reports do not necessarily reflect those of Smithers Rapra Technology or the editor. The series is published on the basis that no responsibility or liability of any nature shall attach to Smithers Rapra Technology arising out of or in connection with any utilisation in any form of any material contained therein.

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Poly(vinyl alcohol): Properties, Applications and Disposal This review report is produced to provide a concise introduction to poly(vinyl alcohol); the material itself, processing, applications and disposal. It will also consider comparable properties of similar materials with which this material is likely to compete. The definitions and requirements of materials that wish to operate in the ‘green’ arena will also be introduced. Poly(vinyl alcohol) is the most commercially important water soluble plastic in use. It is tasteless, odourless, it will biodegrade and is biocompatible. As well as being soluble in water, it is slightly soluble in ethanol, but insoluble in other organic solvents. As environmental concerns over the disposal of plastic wastes have grown and focus has switched towards product life cycle and disposal, poly(vinyl alcohol) has a readymade and viable disposal route. In light of increasing environmental legislation, this will allow it to be utilised in non-traditional areas of use. With increasing interest in the use of biodegradable and sustainable alternatives for mass applications, poly(vinyl alcohol) provides an interesting point of comparative study on a oil-based synthetic material with the properties of a ‘green polymer’. It is also be readily blended with a number of natural materials and can exhibit properties that are compatible with a range of applications. The inclusion of natural fibres and fillers can give further improvements in mechanical properties without compromising overall degradability. Therefore, the potential benefits of this material given its water soluble characteristics are huge, but this must be offset against practical considerations of its long term life cycle in changeable environmental conditions. In the future biodegradable materials could be used within a variety of product applications, but there are, at present, significant penalties in terms of performance, cost and availability. The predominant benefit which can be attributed to biopolymer usage is that the materials themselves can be biodegradable. This of course makes them an increasingly attractive proposition for manufacturers who are faced with increasingly stringent EU legislative requirements when it comes to the environmental performance of their products, or those who wish to tap the market of the environmentally conscious consumer. This review will try to capture current and future trends in this area.

1. Introduction Like all common polymers poly(vinyl alcohol) can be abbreviated. However, unlike polymers such as polypropylene (PP), in which the abbreviations are universally used, poly(vinyl alcohol) does not have a singularly recognised abbreviation. Therefore according to various literature sources it is referred to as PVAL, PVOH or PVA and therefore all these terms, although confusing, are correct in the context of the standards to which they were used. The terminology that shall be used here is PVAL in accordance to British Standard BS EN ISO 15023-1:2006 (a.1). Poly(vinyl alcohol) and its properties have been known to scientists for a long time. It was first prepared by Hermann and Haehnel, Germany, in 1924. It is made by hydrolysing polyvinyl acetate (PVA or PVAc – dependent on where you look). Worldwide consumption of PVAL had reached several hundred thousand tonnes annually in 2006; this is widely predicted to increase by about 2.5% annually between 2006 and 2011. There are a number of worldwide producers of this material with the majority of production based in Asian countries. China has the largest share of the market as of commercial trading figures for 2006 with 45% of the entire market with this figure likely to expand. Japan and the United States are also both large producers and consumers of PVAL materials. Kuraray (Japan) is the largest single manufacturer of PVAL accounting for 16% of all world capacity and offering over 50 different grades of this material. Trade names for PVAL (PVOH or PVA) include Elvanol (DuPont), Mowiol (Kuraray) and Poval (Kuraray). The material exists in the marketplace as fully hydrolysed, medium hydrolysed or partially hydrolysed copolymers or custom blends. Most of the market is dominated by sales of the fully hydrolysed grade of material. This difference in hydrolysis will be explained in Section 4. In line with international standards, grades of this material are presented in terms of the degree of hydrolysis and the viscosity in water at specified conditions. An indication of the range of hydrolysis levels available in the marketplace is shown in Table 1.

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Table 1 Selection of grades of PVAL offered by Kuraray Grade

Viscosity DIN 53015 (a.2) (mPa-s)*

Degree of hydrolysis (saponification) (mol. - %)

Partially hydrolysed

Mowiol 3-85

3.4-4.0

84.2-86.2


PVA 220

27.0-33.0

87.0-89.0


PVA 225

45.0-52.0

86.5-89.0

Medium Hydrolysed

PVA CST

24.0-30.0

95.5-96.5

Medium Hydrolysed

PVA 613

14.5-18.5

92.5-94.5

Fully hydrolysed

PVA 117

25.0-30.0

98.0-99.0

Fully hydrolysed

Mowiol 4-98

4.0-5.0

98.0-98.8

Fully hydrolysed

Mowiol 56-98

52.0-60.0

98.0-98.8

*of a 4% aqueous solution at 20 °C

Using 2008 commercial prices as a general guide, PVAL materials are priced according to viscosity.

is possible to avoid thermal dehydration however, some properties are sacrificed.

Low viscosity materials (classed as having a viscosity less than 0.01 Pa-s), were trading for half the price per tonne (150 Euros), than high viscosity materials (>0.03 Pa-s) which were trading at 300 Euros per tonne. Medium viscosity materials (0.01-0.03 Pa-s) were trading at 200 Euros. However, like all oil-based plastics prices are highly variable.

In China the largest market is as a polymerisation aid in emulsified polyvinyl acetate and polyvinyl chloride (PVC). Therefore, much of the PVAL produced today is used as a protective colloid in the manufacture of polymer emulsions.

2. Application Scope The major uses of PVAL depend on region. In the United States and Western Europe the majority of PVAL is consumed in the production of poly(vinyl butyral) (PVB). This is used in the inner layer of laminated safety glass for automobile window screens. It is made by reacting PVAL with butyraldehyde [CH3(CH2)2CHO] and this market is one which is expected to grow in the future. PVAL finds other uses in a broad range of products produced for example as a protective colloid in the manufacture of polymer emulsions. Other applications include: the binding of pigments and fibres, dip coated articles, protective strippable coatings, the manufacture of detergents and cleansing agents, adhesives, emulsion paints, and solution cast film. These applications all involve the use of the PVAL in solution as its thermal degradation at about 150 °C (crystalline melting point of PVAL ranges from 180 °C to 240 °C), limits its ability to be used in conventional thermoplastic processing equipment without modification. When PVAL is plasticised, it

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The use of emulsifying agents improves the quality of synthesis of PVC and helps properties such as the ability to absorb plasticisers and the production of uniform grain sizes. Other materials commonly used as emulsifying agents are methyl cellulose derivatives or combinations. Two PVAL materials of differing molecular weight may be used together synergistically improving the process. In the formation of emulsified polyvinyl acetate, PVAL acts as a protective colloid. PVAL has excellent properties in emulsion such as ‘wet tackiness’, high strength and it is highly resistant to creep. As with the formation of PVC, the structure of the PVAL affects the emulsion performance of the polyvinyl acetate. For this process, PVAL with an active surface is also required, therefore partially hydrolysed grades are utilised which have residual acetate groups which are hydrophobic in nature. In Japan Vinylon spun fibre is the biggest use of PVAL. It is used in a variety of applications from the manufacture of traditional Japanese dress, canvas, cement reinforcement, agriculture, fishing nets, ropes and paper making (which is the largest market). It can be produced by either dry or wet spinning. This is a different process to spinning from a melt, which is called melt spinning and used for production of fibres


such as polyethylene (PE), PP, polyamide (PA) and polyester. In the case of vinylon a spinning solution is used with most production then carried out by wet spinning. The product is staple fibre. The solution is spun into fibres which pass through a water bath before being drawn and cut into fibres. Dry spinning uses hot air instead of water, drawing and then collection of the filament yarn onto spindles. Vinylon is characterised by a lighter weight (specific gravity of 1.3) than natural fibres such as wool or cotton. It is abrasion resistant, durable and resistance to weathering, chemicals and rotting and has properties similar to cotton in fibre form.

All the applications so far involve the use of the PVAL in solution as its thermal degradation is about 150 °C (crystalline melting point of PVAL ranges from 180 °C to 240 °C). Therefore until recently this limited its ability to be used in conventional thermoplastic processing equipment. However, when PVAL is plasticised, it is possible to avoid thermal dehydration. Melt processing applications are discussed in Section 8.

Demand is also increasing for PVAL fibres as a safer replacement for asbestos fibres and in the use of polarising optical films for liquid crystal displays (LCD) (a.3). The PVAL material is used for optical applications which effectively prevent reflection of light at the surface of image display devices such as plasma display panels (PDP), cathode ray tubes (CRT) and LCD, and exhibits excellent scratch resistance. The film, used for preventing reflection of light has excellent scratch resistance and can be produced at a low cost. In a typical application, the film is formed by successively laminating a hard coat layer, a first high refractivity layer, a second high refractivity layer, and a low refractivity layer.

s #LEANINGANDDETERGENTPRODUCTS

The water solubility and biodegradability of this material are the key properties for its usage. This has also attracted the recent attention of a packaging industry keen to address environmentally friendly solutions to the issue of plastic waste. This will be discussed in Section 5. Other important areas where PVAL water solubility is used include textile sizing agents – the PVAL is applied to protect the textile fibres during production (such as knitting or weaving and so on), then once made the garment can be washed to remove the PVAL.

Therefore, PVAL finds use in variety of market sectors such as (a.3): s !DDITIVESINCONSTRUCTION s !GRICULTURE s (EALTHANDHYGIENEA s (ORTICULTURE s 0ERSONALCAREANDTOILETRIES s 3PECIALITYCHEMICALS s 7ATERTREATMENT PVAL was investigated in the 1970s for use in controlled release of agrochemicals using combinations with pesticides. It is also used in current production of seed tapes. For these kind of applications the polymer must degrade without impact (be it chemical or biological) to the surrounding environment. Therefore, degradation and disposal issues will also be discussed later in the review. PVAL is used in the manufacture of laundry bags and hamper liners for use in health care facilities. The filled bag is sealed shut with an attached adhesive strip. When placed in the washer, the adhesive and bag break down completely during the hot washing and disinfection. The bags are impervious to bacteria and viruses during normal use, as well as resistant to gases, solvents, and cool liquids, reducing the risk of contamination and thereby protecting hospital staff.

PVAL adhesives are used widely with cellulose materials as they give excellent adhesion to them. They are, therefore, used in a range of applications from postage stamps, labels, paper bags to book binding and make an ideal glue for papercraft activities.

In food industries, PVAL is used as a binding and coating agent. The film coating is used in applications where moisture barrier protection properties are required. PVAL protects active components and other ingredients from oxygen, e.g., tablet coating formulations intended for products such as food supplement tablets.

Commercially, PVAL is the most important plastic for production of water soluble film. It is characterised by excellent film-forming, emulsifying, and adhesive properties. It has a high tensile strength, good flexibility, good oxygen barrier properties and good solvent resistance properties.

Other more unusual products include the biodegradable PVAL pet waste bag for picking up pet waste and ecodisposal. It can be placed in the bin or flushed down the toilet. For lazy (or inept) golfers, there are water soluble golf balls made from PVAL. For golfers not willing to look for their balls, these can be abandoned on courses

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to biodegrade naturally. For those who wish to practise their swings while at sea, they can be hit straight into the sea to dissolve. This variety of sectors and applications areas are possible because poly(vinyl alcohol) has a number of useful and tailorable properties. It is odourless and non-toxic, it has excellent film forming, emulsifying, and adhesive properties. It also has good resistance to grease, oils and a large number of solvent materials. It has good mechanical performance with high tensile strength and flexibility, it also has high oxygen and aroma barrier properties. However, these properties are all dependent on the level of humidity. Water, which acts as a plasticiser, causes a reduction in tensile strength, but also increases the elongation and tear strength of the material. The sheer range of applications for this material make it an interesting material of study. However, first a more fundamental introduction to PVAL manufacture and material properties will be given.

3. Manufacture The first commercial production of PVAL was by the company Wacker (Germany) with the trademark Synthofil, which was used as medical sutures. In 1930, Japanese researchers Sakurada, Yazawa and Tomanari successfully wet spun PVAL. In 1950 this was realised commercially as Vinylon fibre (see Section 2). This fibre has high heat resistance amongst other interesting properties.

Unlike other members of the vinyl group, PVAL is not polymerised from a monomer in direct polymerisation, but prepared by hydrolysis of poly(vinyl acetate) (PVAc) in alcohol solution. This is a rubbery, synthetic polymer and partial or complete hydrolysis of the PVAc is used to prepare PVAL. The reaction proceeds via free radical mechanism or suspension polymerisation. Partial or complete hydrolysis removes acetate groups from the PVAc. The resultant material PVAL has the same degree of polymerisation as the original PVAc material. Therefore by varying the degree of polymerisation of the original PVAc a number of different grades of material with different properties can be produced. The reaction can be controlled to produce any degree of replacement of acetate groups. Other materials can be used to produce co-polymer materials which also replace the acetate group. Monomers such as ethylene and acrylate esters are commercially used in this way. Once converted from PVAc the hydrolysed alcohol product is typically in the 87% to 99% range. If it is above 98% it can be considered to be fully hydrolysed with an expected crystallinity value of 40-50% Highly but not fully hydrolysed PVAL has a degree of crystallinity of 30-40% and a melting point of 225 °C. The reduced crystallinty in partially hydrolysed grades is due to the residual acetate groups. Other factors affecting crystallinity are the amount of plasticiser and water present in the compound. The production process used (acid or base catalysed) also has an effect. A lower crystallinity means lower strength but increased water solubility compared to fully hydrolysed (higher crystallinity) grades which can be considered as homopolymers as opposed to mixed vinyl acetate and vinyl alcohol copolymer. Chemical representations commonly used to represent PVAL are shown in Figure 1.

Figure 1 Molecule of PVAL (left) and chemical representations (right and centre)

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4. Polymer Chemistry The physical characteristics and specific functional uses depend on the both the degree of polymerisation and hydrolysis produced. PVAL is classified into classes namely: partially hydrolysed and fully hydrolysed. PVAL is crystalline in nature, this is unusual since it is an atactic linear polymer, meaning the positioning of the side chains of secondary alcohol groups is random. This is generally accompanied by an inability to crystallise. In fact PVAc is not crystalline, but PVAL which contains smaller hydroxyl groups, is typically crystalline regardless of stereoregularity. This is because hydroxyl groups do not disrupt the crystalline lattice structure as their small size allows them to ‘slot’ in. However, in contrast, the presence of residual acetate groups greatly diminishes the crystal formation and the degree of hydrogen bonding because of their more bulky nature. Therefore, polymers that are highly hydrolysed have a high tendency to crystallise and to undergo hydrogen bonding. As the degree of hydrolysis increases, the molecules will very readily crystallise, and hydrogen bonds will keep them associated if they are not fully dispersed prior to dissolution. At degrees of hydrolysis above 98%, manufacturers of PVAL advocate a minimum temperature of 96 °C to ensure that the highest molecular weight components have enough thermal energy to go into solution.

Increasing levels of hydrolysis leads to increasing crystallinity This also allows a level of control to be exerted over the crystallinity produced and the physical characteristics and specific functional uses of PVAL vary with this property. The crystallinity affects the water solubility, strength, gas permeability and thermal characteristics. Since the crystallinity is dependent on both the degree of hydrolysis and the average molecular weight of the polymer it also depends on the degree of polymerisation that occurs. The level of hydrolysis will therefore have a direct effect on the properties and it is necessary to distinguish these materials into levels (partially, medium, fully hydrolysed). The actual degree of hydrolysis depends on how many percentage mol of residual acetate groups remain, as PVAL is characterised by the presence of the polar OH groups in the structure. For ISO 15023 (a.1), the level must be equal to or above 70%.

Because PVAL refers to the material that can be both fully and partly hydrolysed, it can actually be considered in partially hydrolysed cases to be a co-polymer of vinyl acetate and vinyl alcohol monomer (which does not actually exist). The monomer components may be distinguished if necessary using the convention V-AL and V-OAc. Therefore PVAL is characterised by the presence of polar alcohol (OH-groups), and these groups give rise to reduced water solubility and also allow other reactions to take place. Increasing hydrolysis leads to: s REDUCEDWATERSOLUBILITY s INCREASEDSOLVENTRESISTANCE s INCREASEDTENSILESTRENGTH s INCREASEDADHESIONTOHYDROPHOBICSURFACES In many cases, however, a partially or fully hydrolysed material may be used for the same application. For example in adhesives, where water resistance is required, a fully hydrolysed material may be used and where water resistance is not an issue, a partially or fully hydrolysed material may be used. It is a water-soluble synthetic polymer that is it is made from petrochemicals. So although it is biodegradable, it is not a biopolymer. A biopolymer is a material made from a biomaterial such as plant starch. This distinction will be discussed in Section 10.

4.1 Viscosity in Solution In water solution partially hydrolysed PVAL (88% and below) has a stable viscosity which does not change over time. However, the viscosity of a solution of highly hydrolysed material will show a gradual increase in viscosity over time, and if left long enough may even gel. This tendency to increase in viscosity over time, increases fairly linearly with concentration. The films produced from partially hydrolysed solutions are characterised with poor water and heat resistance. Those from fully hydrolysed grades have the opposite properties being water and creep resistant properties. Through the use of additives it is possible to stabilise or destabilise those changes in viscosity which occur.

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5. Water Solubility The main use of PVAL is when it is dissolved in water. Poly(vinyl alcohol) is among a group of water-soluble plastics that have a long history of use in niche applications. Many of these polymers are biologically stable when they are in the solid state but will biodegrade readily once they are dissolved. As PVAL is formed by hydrolysis of PVAc, by controlling the degree of hydrolysis, its solubility can be modified, which results in grades that will dissolve only in hot or cold water. Some grades can be mass produced by extrusion, injection moulding or film blowing (to produce potentially readily disposable components), but others must be cast from solution. Single dose laundry blocks or liquids have become commonplace in many households. These are water soluble films used for the packaging (as you will find if you accidentally get them wet, they become very sticky.) Surprisingly the first use of water soluble packaging was in the 1960s, this was for carrying harmful chemicals in agriculture. It is relatively more recently that they have become such a commonplace item for household detergents and cleaning items. As already mentioned, the solubility depends on a number of factors such as the degree of polymerisation and degree of hydrolysis. The degree of hydrolysis is particularly important because of the inherent chemical structure. The many hydroxyl groups mean it has a high affinity for water and the hydrogen bonding between the hydroxyl groups impedes the overall solubility. In contrast, partly hydrolysed PVAL contains acetate groups. This acts in the opposite way to weaken the hydrogen bonding and increase solubility and there is a relationship between temperature of solubility and presence of acetate groups. Therefore, the behaviour of PVAL in solution is quite complex. However, generally a partially hydrolysed version of the same material will be more soluble at a lower temperature with solubility increasing as hydrolysis levels increase. Commercial water-soluble films can be tailored to dissolve in water at very specific temperatures. PVAL is not the only water soluble polymer on the market. Other water soluble polymers are shown in Table 2.

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Table 2 Water-soluble polymers Type

Production

PVAL

Source

Synthetic*

Non-renewable*

Ethylene vinyl Synthetic* alcohol (EVOH)

Non-renewable*

Cellulose acetate

Natural

Renewable (cellulose)

Chitosan

Natural

Renewable (invertebrates)

* made from fossil fuels

The term non-renewable source refers to the use of fossil fuels, which are finite in nature. PVAL and EVOH are highly unusual, synthetic crude oil-based polymers in that they dissolve in water. EVOH is most commonly used as an oxygen barrier layer in multi-layer film packaging (see Section 7.1) although it is expensive to use and the high price limits its applications elsewhere. PVAL is also the only polymer consisting of a carbon-carbon backbone that biodegrades. Polymers made from renewable resources include plant-based materials such as plant starch (which can be renewed by re-planting crops) and animals sources such as chitosan (found in insect exo-skeletons). Chitosan also has good gas barrier properties and is used as a coating for other biodegradable polymers and edible coatings. Both cellulose acetate and chitosan are water-soluble. The water solubility of polymer materials means that they can end up as pollutants in water ecosystems (river, ocean) and affect aquatic life if they are not monitored and removed. Removal is done by microorgasms for PVAL and other similar potentially water soluable pollutants include polyacylics, polycarboxylates, polyethers and polyglutamic. For PVAL, research as far back as 1936 (a.6) found that PVAL in waste water was biodegraded by a phytopathogenic organism of fungal origin, Fusarium lini. The by-products being water and carbon dioxide. Since then many studies have been carried out on PVAL degradation in both aerobic conditions and soil samples with satisfactory results. The actual biodegradation mechanisms are beyond the scope of this review however the reader is referred to a survey carried out by Chiellini and co-workers (a.7) in 2003 for an overview of this subject. The solubility of PVAL makes a big difference to the final application. For example consider three alternative PVAL materials that can be considered as very soluble, moderately soluble and slightly


soluble. A guide to potential applications based on this property is shown in Table 3.

and partly hydrolysed materials are weaker than fully hydrolysed materials.

Table 3 Solubility as application guide

A higher degree of polymerisation gives increasing strength, but humidity has the effect of a plasticiser, swelling the structure to make it softer and tough.

Very soluble

Moderately soluble

Slightly soluble

Pharmaceutical capsules which dissolve to release drugs

Loose fill packaging

Food packaging

Medical sutures

Agricultural films

Diaper films

6.1 Barrier Proporties

Detergent single Single use food dose blocks service items

Medical containers

Life span short

Life span: high – must survive until disposal

Life span: medium

As we have seen, the solubility of PVAL depends on both the molecular weight and the level of hydrolysis. To add to this, PVAL that is partly hydrolysed is less dependent on temperature to be soluble. For highly hydrolysed grades however, it may be necessary for solutions to reach temperatures just under 100 °C before dissolution occurs. For disposal of items such as food packaging, diaper films and medical containers, left to degrade in the environment, it is unlikely that they would ever reach high enough temperatures to dissolve in rain water for example. It is therefore, necessary to consider whether degradation by environmental conditions or degradation by dissolving into water is the required outcome. Methods of degradation will be covered later in Section 14. Partially hydrolysed PVAL is easier to dissolve than fully hydrolysed PVAL

6. PVAL Film Properties PVAL is the most commercially important water soluble film, therefore, it is worth taking a look at the major properties of these materials. Given their water soluble nature it is probably not surprising that the first consideration is that the resultant mechanical properties depend on humidity. High humidity produces a film which is soft and tough. Low humidity gives a hard and brittle material. These depend initially on the degree of polymerisation since tensile strength and elongation increase with degree of polymerisation

PVAL materials have excellent oxygen barrier properties (and also act as a barrier to carbon dioxide and nitrogen). These values are comparable to the performance of EVOH and much better than the common commodity packaging materials listed in Table 4.

Table 4 Oxygen permeability of common materials and PVAL (30 μm film, 50% humidity) Material

Oxygen Permeability (ml/m2/day)

Hot water soluble PVOH

0.24

Warm water soluble PVOH 0.36 Cold water soluble PVOH

1.85

EVOH

0.29-2.4

Nylon 6

26-38

PET

40-80

PVC

50-390

High-density polyethylene (HDPE)

1700-2400

PP

2,000-10,000

Low-density polyethylene (LDPE)

12,000

An increase in dissolution temperature (and crystallinity) improves the performance of the oxygen barrier. However, the downside is the affinity to water. Water vapour will permeate through the films and therefore PVAL is a poor barrier to water vapour. Interestingly this is the opposite of polyethylene which allows oxygen to pass through its structure but not water vapour. Wet PVAL film has little strength but a dry film has good tensile properties. PVAL has found application as a barrier layer in flexible packaging but not in rigid packaging (such as bottles) where EVOH and PA are utilised. Whilst aluminium of micrometer thickness is traditionally used in flexible packaging, creating a virtually perfect barrier, using plastics by lamination or co-extrusion gives high (but not perfect) barrier performance but at a better cost

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performance. Other flexible packaging barrier materials used in this way include poly(vinylidene chloride) (PVDC), EVOH or PA.

affected by the degree of polymerisation and the degree of hydrolysis.

However, it needs to be considered that PVAL, EVOH and PA are only effective barriers in a dry state. Therefore, sandwich constructions in which they are protected by materials with water barrier properties are necessary to maintain the oxygen barrier properties of these materials.

6.2.4 Water Sensitivity and Hygroscopy

6.2 Other Film Properties

PVAL films will swell and take up water if immersed. Partially hydrolysed grades have higher levels of hygroscopy and solubility to water vapour than fully hydrolysed grades. These factors and the rate of swelling can all be decreased by heat treatment which increases the crystallinity of the film.

6.2.1 Mechanical Properties 6.2.5 Adhesion Characteristics Degree of polymerisation affects both the tensile strength and elongation film properties, so that as the degree of polymerisation increases so does the strength. The tensile strength also increases with a rise in the degree of hydrolysis. However, as well as these factors, the humidity also has a marked effect on physical properties. At low humidities, PVAL film is hard and brittle, whilst at high humidity it is soft and flexible due to the plasticising effect of the water vapour. This dependence is greater for partially hydrolysed grades than for those that are fully hydrolysed. Humidity leads to increased flexibility and softness.

As the degree of hydrolysis increases there is a change in the relative number of acetate and hydroxyl groups present. This in turn creates changes in the adhesion character of the film. When used as an adhesive agent, low degrees of hydrolysis give adhesion to hydrophobic surfaces, higher degrees of hydrolysis lead to adhesion to hydrophilic (strong affinity for water) surfaces.

6.2.6 Antistatic PVAL is resistant to static build up and this property can be useful in packaging applications where atmospheric dust is present.

6.2.2 Plasticiser Effects Water acts as a plasticiser for PVAL whether by the action of humidity or as a solution. At low humidities the same effect can be achieved by glycols which serve to prevent the PVAL film from becoming hard and brittle. For thermal processing techniques such as injection moulding it is necessary to add plasticiser to prevent premature degradation. These will be discussed further in the thermal processing section.

6.2.3 Oil and Solvent Resistance PVAL is highly resistant to oils (animal, vegetable or mineral origin) and organic solvents (aromatic and aliphatic hydrocarbons, esters, ethers and ketones). This resistance like many of the other properties of PVAL is

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7. Solution Processing The spinning of Vinylon fibres from solution, primarily of interest only to the Japanese market has already been discussed. Another process using PVAL in solution to spin fibres is electrospinning. In this case very thin, nano-sized fibres can be produced, allowing the resultant fibres to be used in a range of medical and filtration applications. The major drawback with electrospinning is the volumes that can be produced. If large volume equipment comes onto the market, this type of manufacture could be applicable to more than just niche markets. Since many applications described here are carried out in solution, it is worth considering how these


solutions are made. These methods can also be used to differentiate between a fully hydrolysed and partially hydrolysed grade. It has been shown that the solubility is dependent on two factors, degree of polymerisation and hydrolysis. Fully hydrolysed grades are not really soluble at room temperature so a stirred water/PVAL mixture will need to be heated to nearly boiling to ensure full dissolution. For partially hydrolysed grades, the plasticiser effect of the water and solubility means the solute (PVAL in this case) tends to form lumps if prepared in the same way as fully hydrolysed grades, therefore in this case, the PVAL should be added slowly to the solution whilst stirring. The temperature can be raised if necessary to speed this process up. Whilst solution concentrations obviously vary from application to application, a 10% solution is a very common dilution rate for PVAL and can therefore be considered as an indicator of the levels of PVAL used in solution for the purposes here.

low degradation reaction temperature means that melt processing applications a limited to only materials with low hydrolysis levels or materials that a heavily plasticised (which generally meant sacrificing the useful properties inherent in the PVAL materials in the first place). Therefore, until the last decade, the unwelcome onset of thermal and shear degradation during melt processing of PVAL limited the use of conventional thermoplastic melt technology. Application of PVAL was limited to aqueous solutions and cast films. However, advances in PVAL polymer formulation mean that the properties of PVAL can now be retained during thermoplastics processing and it is possible to produce water-soluble, non-toxic, biodegradable plastics by conventional thermoplastics forming techniques. A brief description of some of these techniques follows. Extrusion Process for producing either pellets for other heat forming processes such as injection moulding, sheets (which can also be used for thermoforming) or profiles such as tubes, pipes and rods. Film blowing

8. Melt Processing PVAL has a decomposition temperature of 180 °C. However it does not melt below 180 °C, and has a melting point range of between 180 and 240 °C. Some properties are shown in Table 5. Therefore thermal processing of PVAL presented a considerable challenge worldwide.

Table 5 Properties of PVAL Property

Typical value

Density

1.19-1.31 g/cm³

Melting point

180-240 °C (dependent on degree of hydrolysis)

Boiling point

228 °C

Degradation temperature (unplasticised)

180 °C

Unplasticised PVAL degrades at temperatures above 180 °C due to water elimination from the chemical structure. Further degradation can cause discoloration and crosslinking to occur as the hydroxyl and acetate side groups are eliminated. Whilst the melting point of PVAL can vary between 180-240 °C depending on the level of hydrolysis, the effect of the relatively

Process for producing thin films products such as shrink wraps and carrier bag film. Injection Moulding High shear and pressure process for production of complex and mass produced components such as mobile phone covers, lids, automotive door handles, motorcycle helmets. Thermoforming Low pressure process which deforms sheet material into relatively simple shapes such as trays, cups and shallow tubs. Blow Moulding Inflation production process which produces hollow articles such as bottles, containers and tanks. Melt spinning Production of thin fibre strand produced from molten plastic passed through a multi-holed profile. (This is not to be confused with spinning from a solution, as in the production of Vinylon fibre or electrospinning which produces PVAL nano-fibres and is also a solution process.)

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PVAL melt processing temperatures tend to range between 180 and 240 °C. This depends on the level of hydrolysis and specific formulation and additives used. Generally fully hydrolysed grades, which have higher melting points, require higher temperatures to be used. They also tend to be harder to process. To improve the processibility of PVAL it is necessary to use a plasticiser and lubricants which lower melt temperature and viscosity and therefore allow lower processing temperatures to be utilised. The degree of degradation is strongly influenced by acetate groups which liberate acetic acid during processing which catalyses further degradation to occur. Higher levels of hydrolysis 98 mol% are more resistant to degradation that 88 mol%. Temperature rather than shear appears to be a dominant factor in this. In such applications, the basic PVAL must be plasticised so as to reduce its melting point, and obtain a thermal processing window for processing. In general plasticisers, such as glycerol, polyethylene glycol, sorbitol and other compounds have been used. Mowiflex TC is an example of a thermoplastic melt processable material currently sold by Kuraray. This can be used to produce blown and sheet film as well as injection moulded components. As expected of PVAL, it is moisture sensitive and sold in moisture resistant bags, however, it can be dried if needed at 60-80 °C for 6-8 hours using conventional air drying equipment. Therefore, it can be treated like other moisture sensitive materials such as Nylon routinely used in processing.

to parameters used to process polyethylenes. This can be performed on conventional equipment using hot or cold runners to produce a variety of moulded components. With the fast cycling time possible with injection moulding it is possible to mass produce a variety of components and products very rapidly and economically. An example component is exhibited in the Science Museum, London, UK. This is a biodegradable mobile phone casing developed by researchers at the University of Warwick's, Warwick Manufacturing Group, in conjunction with PVAXX Research & Development Ltd. A water soluble mobile phone case was the component. However, this idea had a twist. By imagining the components end-of-life and burying the case after use with a sunflower seed beneath it, the phone biodegraded and the sunflower seed began to grow and eventually flowered. This was timed with the growing awareness of the problem of plastic waste and sustainability, as well as the newly introduced European Union WEEE Directive (waste electrical and electronic equipment) (a.8) which covered the ever growing problem of electrical waste. Therefore, discarded mobile phones were a hot topic and this application captured public attention. However, problems of water proofing the product for use (in rain or wet environments for instance), mean as yet this application is not in commercial production.

8.3 Film Moulding 8.1 Extrusion Tubing and hoses produced by extrusion retain many of the properties recognisable from solution processing. They are highly flexible and retain excellent solvent resistance to oils, greases and other chemicals. Processing is carried out on standard extruders with low residence times. Keeping residence times as low as possible is one key factor in successful processing of PVAL materials. Thermal damage produces discoloration of PVAL products, as it does with many other thermoplastic components.

8.2 Injection Moulding For injection moulding of PVAL, recommended mould tool temperatures are in the 70-80 °C range with melt temperatures ranging from 190-220 °C. This is similar

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An extrudable PVAL material for blown film application was marketed by A. Schulman, Akron, USA under the name Aquasol. It is reported to have the same physical properties as the cast film and could be used in conventional polyolefin melt equipment. The target market to be biodegradable replacement for LDPE (a.9). Most of the market in these film applications is for disposable packaging. Table 6 shows a typical range of properties shown by various grades of PVAL in comparison to other film materials. Most marked here is the tear strength and tensile strength which is actually comparable to that produced by a polypropylene material. PVAL materials also show good puncture resistance and impact strength. However performance is markedly affected by the degree of hydrolysis and therefore the crystallinity of the base material as well as the molecular weight, distribution and branch structure.


Table 6 Properties of PVAL and common films at 25 μm Property

PVAL

Cellophane

PVC

LLDPE

OPP

Light transmission (%)

60-66

58-66

48-58

54-58

70-86

Light reflected (%)

81

60

80

22

80

Tear strength (Elmendorf) (g/mil) 260-3000

20-40

390-780

290-980

4-6

Tensile Strength (MPa)

40-90

55-131

20-76

17-19

25-30

Elongation at break (%)

110-400

-

5-250

50-600

70 -100

LLDPE – linear low-density polyethylene OPP – orientated polypropylene

Blow up ratios may vary according to supplier of PVAL material. According to Kuraray, the grade Mowiflex TC can achieve a blow up ratio (inflation ratio) of 1:8.

8.4 Blow Moulding While PVAL can be used as a barrier layer in multi-layer bottles, generally EVOH is used for rigid packaging applications as produced by blow moulding. For example, with PET bottles, EVOH can be used as a barrier layer to keep the carbonated contents fizzy. Another commonly used barrier layer is PVDC, however, the use of these materials as packaging materials is generally declining due to environmental issues. Therefore other materials such as EVOH, PVAL, coated PP films, Nylon resins called MXD6, and PET films which are silica- or alumina-coated are becoming more popular for gas-barrier purposes. Recently, various types of oxygen scavengers have been developed and applied as active packaging materials. In fact, PET bottles having oxygen barrier or scavenging properties are now used in the production of plastic beer bottles in Europe and the United States. Because of the environmental interest in the problems of plastic waste disposal and the inherent solubility and biodegradable nature of PVAL, interest in this material has heightened for these processes which are capable of high production rates.

of these materials is growing. Legislative demands for sustainability and biodegradable disposal such as composting are also drivers towards the use of biodegradable materials (see Section 15). The major problem with waste packaging here has to do with product life cycles. Packaging materials have expected lifetimes which are very short – days or weeks. A plastic used in construction on the other hand, such as PVC window frames are expected to last for decades. Therefore, discarded packaging makes up a considerable proportion of the plastic waste stream. This is therefore an ideal outlet for biodegradable plastics which can be used for packaging items such as food films, single use food containers, disposable plates and cutlery and bottles. These products can be mass produced through processes such as injection moulding, blow moulding and film blowing if cost effective and reliable supplies of biodegradable materials are available. However, this is not always the case.

9.1 Active Packaging Active packaging is where a packaging system actually does more than simply package food. One such example would be to transfer antimicrobal agents from a carrier film and into the food to maintain a predetermined and useful concentration to help with food safety or food preservation for example. For such purposes, properties such as diffusion, polymer swelling and dissolution are important. The properties of PVAL make it a polymer of interest for such new applications. Antimicrobotic release systems described here have until now mainly been used in medical and pharmaceutical applications.

9. Packaging Biodegradable packaging is a direct response to the problem of waste packaging and disposal using petroleum-based synthetic plastics. Material performance and cost are the main barriers to increased biodegradable market share as consumer acceptance

10. PVAL in Medicine: Hydrogels Hydrogels are 3-dimensional crosslinked hydrophilic polymer networks which do not dissolve in water

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at body temperatures but swell when exposed to an aqueous medium (a.5). PVAL is one of the most well known hydrogel materials and can be caused to crosslink as required. PVAL has good biocompatilbility and this has meant it has found application in a variety of medical applications including contact lenses, implants, drug delivery systems, medical implants and also wound dressing. Hydrogels in wound dressings can incorporate useful features such as pain control, ease of changing, transparency to allow monitoring of healing, absorbtion and prevention of fluid loss, bacterial barriers, good oxygen permeability, and good handling or control of drug dosage. Hydrogels provide an interesting comparison to the field of active packaging whereby the packaging is also incorporating useful features. As a biocompatible material PVAL is also of interest for surgical grafts and implants as well as medical devices.

conditions. Continued apprehensions regarding the increased cost of crude oil due to the uncertainty of global supply is compounded by the ongoing concerns regarding the current political climate. These drivers have forced manufacturers and government to consider alternative solutions to reduce dependence upon oil. Bio-based alternatives to fossil fuel feedstocks are growing across the globe, and the growth in biopolymer development is finding increased favour within many industrial sectors. Improvements in economies of scale and sales growth of between 20-30% per year would indicate that biopolymers may soon be competing with commodity polymers (a.17). Therefore, biopolymer itself is a term which can be used to describe a wide range of materials. There are two categories into which a material can fall in order to be classified as such: s 4HEMATERIALMUSTBEMADEFROMANON FOSSILORIGIN material or s 4HEMATERIALMUSTBEBIODEGRADABLE

11. Biopolymers Biopolymers is short for biological polymers. These are polymers which occur in nature produced by microorganisms, plants and animals. In the 1970s, the first impacts of the energy crisis began to focus the development of alternatives to traditionally employed materials. The response was to begin active research in the area of biopolymers. As early as the 1980s, the main advantage for using biopolymers became their capacity to decompose under natural

Carbohydrates, proteins and polyesters (which are produced by microorganisms) are all found abundantly in nature. Not surprisingly, these materials are all naturally biodegradable. Common examples of each is shown in Table 7. There are a large variety of materials which can be categorised as a biopolymer. These often take on other names such as low environmental impact polymers, or green polymers, but for the purposes of this report, the term biopolymer shall be used. Within the category of polymers which are produced from bio-feedstocks, there are three types of biopolymer - those which are

Table 7 Examples of polymers in nature Biopolymer

Plants sources

Examples

Animal source

Example

Carbohydrates

Polysaccharide

Cellulose Starch Chitin

Glycosaminoglycans

Hyaluronan

Proteins

Amino acids

Soy protein Amino acids Wheat gluten

Polyesters

Produced by bacteria Lactic acid – found in microorganisms and animals

PHA Polymerisation of lactic acid makes poly(lactic acid) (PLA)

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Collagen Casein Keratin


naturally occurring within the environment (including those from polysaccharides, polypeptides and lipids), those which are manufactured synthetically - i.e., they are man made biopolymers in an attempt to address the problems and issues which are currently being faced, and then hybrid, composite materials which are beyond the scope of this review. There are opportunities to employ petrochemical based materials in order to develop a hybrid composite which can extend product ranges and enhanced competitiveness. Increase in the production, and subsequent use of biopolymers could be attributed partly to the increasing awareness of the damage to the environment caused through the use of fossil resources, which are widely recognised as being a finite feedstock (a.18). Security of supply, particularly within the current political and economic climate is another significant factor. Some natural polymers can also be extracted and chemically modified to produce thermoplastics. For example, Polymerisation of lactic acid makes poly(lactic acid) (PLA). With the exception of poly(lactic acid) (PLA) these polymers are all naturally produced by nature. In the case of PLA, a monomer from nature, lactic acid, is polymerised by man to produce PLA. So it could be argued that this is a type of synthetic material however, it retains its biodegradability and has a renewable source. It is therefore generally considered to be a biopolymer. Therefore this section also includes polymers from renewable resources that can be polymerised to create biopolymers that are biodegradable and may be naturally produced or synthetically produced. Biopolymers may be synthetic or naturally occurring in origin, but in order for them to be of significant benefit to the manufacturing sector they have to be competitive on financial, performance and also availability criteria. To switch from a biopolymer to a bioplastic it is necessary to add additives, just like conventional polymer to plastic processes. Therefore, bioplastics are plastics manufactured using biopolymers with other additives, however, they do not necessarily retain the biodegradability properties of the biopolymer. The major advantage of using biodegradable materials is that they can be naturally diposed of through processes such as composting. But the biodegradability of raw materials does not necessarily mean that the product or package made from them (e.g., coated paper) is itself compostable.

However, there is widespread interest for biopolymers and bioplastics among consumers. The public perception is that conventional plastics are environmentally unfriendly. The brand of ‘sustainability’ can provide an image benefit. However, for manufacturers the environmental benefits of biodegradable packaging must be reflected in cost advantages, if large scale applications are to become feasible. Therefore, in the short term, it may be preferable to communicate the functional advantages of biodegradable packaging rather than its compostability. Biopolymers can have advantages for waste processing. Coated paper (with for example, polyethylene) is a major problem product for composting. Although such materials are usually banned from inclusion in organic waste under separate collection schemes, some of them usually end up in the mix. The paper decomposes but small scraps of plastic are left over in the compost. The adoption of biopolymers for this purpose would solve the problem. Whether the use of a bioplastics will contribute to a more sustainable society is a question that will have to be studied by a representative life cycle analysis (LCA) of each application and by comparison with existing applications. Representative LCA are needed at material and product levels; they must make allowance for future developments in biopolymers and take account of all relevant environmental impacts associated with the complete product life cycle, including the depletion of raw materials, the agricultural use of fertilisers and pesticides, transportation, utilisation and waste disposal. Biopolymers can be categorised as either: s .ATURALLYOCCURRING s 3YNTHETIC

Naturally occurring Naturally occurring biopolymers are those which are formed organically by the earth's natural resources, with the most common natural biopolymers being derived from starches and celluloses. Starch is found in corn, potatoes and wheat and is therefore offers a potential opportunity for farmers wishing to develop non-food crops. Cellulose is the most plentiful carbohydrate in the world. Natural biodegradable polymers are generally produced in nature by all living organisms and as a class, they represent truly renewable resources since they are predominantly biodegradable, even if this process is slow as they are produced in nature (a.20). The synthesis of these materials involves enzymecatalysed, chain growth polymerisation reactions of activated monomers, which are typically formed

15


within cells by complex metabolic processes (a.19). Predominantly these polymers are formed from one of the three following categories: s 0OLYPEPTIDES These protein materials tend not to be soluble, so they are more often employed in their natural form. Prime examples of these include wool, silks and collagens. Gelatin, however, is a water-soluble biopolymer and as such has significant implications for use within a number of industries, particularly pharmaceutical and medical applications. s 0OLYSACCHARIDESINCLUDINGSTARCHES celluloses, etc) Polysaccharides include the biopolymers which can be categorised as starch, cellulose and chitin based. Cellulose and starch based biopolymers have attracted the most interest due to their wide availability and relative low cost, but other complex carbohydrates are also of interest. Starch is the primary carbohydrate reserve in both plant tubers and seed endosperm. The largest source of starch worldwide is from maize, but other contributors to the starch stocks include wheat, potato and rice. It is an attractive proposition to biopolymer developers due to its abundant stock and subsequent low cost. Starch films have been employed particularly within packaging films, and the biopolymer Mater-Bi, manufactured by Novamont is predominantly starch-based. Corn starch is the raw material from which poly(lactic) acids (PLA) are derived. Thermoplastic starch and starch blends such as with PVAL and aliphatic polyesters are available. Naturally produced polyesters including PVB, polyhydroxy butyrate (PHB) and poly(hydroxybutyrateco-hydroxylvaleratevalerate) (PHBV). Celluloses are also well represented within nature in amongst other forms, wood and paper. Cellulose is a polysaccharide as it is derived from sugars - it is repeated units of the monomer glucose. Cellulose biopolymers have been used for packaging particularly for confectionery and cigarettes. Chitin is a naturally occurring material found in the animal kingdom, in the shells of crustaceans and insects. In its original form, chitin is not soluble, but chitosan (partly deacetylated chitin) is. Both materials have found favour in the cosmetic industry due to their water-retaining and moisturising properties.

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s ,IPIDS These materials constitute those derived from oils and fats. Triglycerides are extracted from sunflowers, rape and soya oils. Cashew nut shell liquid is also employed from this classification. The development of rape and soya oils has lead to an increased volume production for use within non-food alternatives and this has had a subsequent impact upon the overall material cost through an increase in global demand (a.19).

Synthetic Synthetic biopolymers are those which are not found naturally occurring and as a result are artificially manufactured by man. Generally these are derived from fossil fuel materials, much in the same way as traditional commodity polymers. These materials include polycaprolactone (PCL), PVAL and EVOH. Polycaprolactone (PCL) have been available in differing forms since the mid 1970s, but whilst the low melting point of the material makes thermally accelerated degradation an increasingly attractive proposition, it means that the material cannot be used in applications that will generate some heat. Current uses for PCL include orthopaedic casts and adhesive mould agents. Other aliphatic polyesters include polybutylene succinate (PBS). Aliphatic-aromatic copolyesters and hydro-biodegradable polyesters such as modified PET are also available.

12. Blends A blend is a combination of two or more materials whose objective is to achieve a superior performance from the composite than is available from the separate constituents. Natural polymers have been introduced in different kinds of blends as both polymers and as fillers in order to improve biodegradability. Starch has been used widely for this reason due to its low cost and large availability in the market. Blend materials are produced by processing of starch with biodegradable polymers such as PVAL, PLA, PCL and PHB plastics (PHBV) to mention but a few. Other natural polymers blended with biodegradable polymers to produce biodegradable composites materials include: cellulose, pectin, chitosan, lignin, soy protein and wheat gluten.


13. Blends of PVAL

Table 8 Starch-PVAL Blends Commercially Available Polymer Type

13.1 PVAL-Starch Blends

Starch-PVAL blends

PVAL can be blended with thermoplastic, watersoluble starch, (e.g., potato starch) to produce readily biodegradable plastics. The blends show only one melting point, which is lower than those reported for either blend component. This suggests a miscibility between the two components. Some PVAL-starch blends commercially available are shown in Table 8.

Tradename

Origin

Novon

Japan

Novon

USA

Mater-bi

Italy

Thermoplastic starch (TPS) cannot be drawn into a film by itself as it is too sticky. However, in combination with PVAL, thin film (less than 200 μm) is easier to process than with PVAL alone. This is because the TPS improves the melt strength and elongation properties. These blends also show improved moisture

Degradation occurs via hydrolysis and biodegradation of the sugar molecules. Water, plasticisers (such as glycerol and sorbitol) and other processing aids are used to prepare the blends which allow a reduction in the cost of the material but with many of the useful properties of the PVAL retained. As both materials are available individually, manufacturers are able to produce their own custom blends.

absorption in humid conditions and offer considerable more resistance to some chemicals than basic PVAL film formulations. Whilst the TPS improves the viscosity characteristic for film blowing, it is offset by a drop in tensile strength and puncture strength. Also the water solubility time is increased as the wet strength decreases. This can be seen in Table 9.

These materials have found applications in packaging. For example, a water-soluble starch/PVAL compound including silicate nanoclay is used in Australia for thermoformed candy trays (a.10).

These materials are suitable for many mainstream PVAL water soluble applications such as hospital and medical disposal bags, dissolvable packaging for detergents and other cleaning items (toilet

A further application for this material is in loose fill packaging materials. These are expanded products with densities ranging from 0.01 to 0.1 g/cm3. Water solubility can be achieved in under three minutes.

blocks, tablets detergents) and others already listed in this review. However, these blends are cheaper to produce.

Table 9 Properties of PVAL and TPS Property

PVAL 1

PVAL 2

PVAL/TPS 1

PVAL/TPS

TPS content (%)

Test Method

0

0

50

50

Film thickness (μm)

50

40

50

40

40

75

25

35

Tensile strength Dry (MPa)

ASTM D882 (a.11)

Tensile strength Wet (MPa)

ASTM D882 (a.11)

Elmendorf tear, kg (N)

ASTM D1004 (a.12)

3.0

0.45

1.50

1.00

Solubility Properties –dissolution time (s/˚C)

ASTM D5226 (a.13)

60/10

70/65

100/10

185/65

15

0.5

17


13.2 Other Blends Whilst PVAL-starch blends are sold commercially there are other blends of interest being developed. Blending has long been done with conventional plastic materials and the benefits are clear, by varying specific amount of the components a number of varying and tailor made properties can be produced.

artificial skin) (a.15). The resultant membrane showed interesting properties: being superabsorbent and compatible with human blood and further research is ongoing in this area.

14. Degradability Therefore blending a biodegradable but synthetic material with a biopolymer is therefore a new avenue for polymer manufactures to explore. A whole range of polymers and copolymers have been examined by academia. It has been found cellulose and PVAL form compatible blends whilst starch, gelatine and lignocellulosic materials produce incompatible PVAL blends.

13.2.1 PVAL/Gelatin Blends Gelatin has a natural polymer source (amino acid) and is actually denatured collagen. Gelatin is obtained from animal skin and bones and waste gelatine disposal is an issue in its own right. Diversion of waste gelatine into other applications is therefore advantageous. Like PVAL, gelatine possess film forming properties and is used in a variety of applications where this property can be utilised, such as sausage casings, thickening agent (food industries), as an adhesive in book making and as drug capsules (pharmaceutical). The combination of the two materials is therefore of interest. Two different areas of research with the materials are outlined next, one in agriculture and one in medical applications. PVAL alone can act as a soil conditioner, gelatine alone can act as a nitrogen fertiliser. The combination of the two could provide self-fertilising films (a.14). It would also increase water permeability of films but keep their mechanical integrity. The components are immiscible on a macromolecular level but regardless of this, the film properties of a cast solution are improved by material combination if PVAL levels are kept at 80% or more. However, it appears that the more biodegradable gelatine is rendered less active by the addition of PVAL whose own biodegradability remains relatively unchanged by the addition of gelatin. When combined in solution and cast as a film, PVALgelatin forms a hydrogel membrane. One potential application for this material has been identified by researchers as a moist wound dressing (temporary

18

The issue of degradability and biodegradability of plastics and biomaterials can be confusing. There are a number of materials that can be degraded but not biodegraded. Therefore it is worth clarifying what these terms actually mean: Degradation of plastic: a change in the chemical structure resulting in failure of physical properties or appearance. Degradable plastic: a plastic which undergoes degradation at specific environmental conditions. This is determined by a standard test method and specified change over time of the property measure (such as physical property or appearance). Examples of this type of degradation could for example be photodegradation, biodegradation or composting. Photodegradable plastic: where degradation is the result of daylight. Biodegradable plastic: one which degrades over time, through the action of nature. In the correct conditions, naturally occurring organisms such as bacteria, algae and fungi can metabolise the material to biomass. However, those materials derived from fossil fuels can also result in carbon dioxide being released into the environment during the degradation process. Compostable plastic: where degradation occurs during composting by biological processes at a suitable rate and leaves no visible or toxic residues. The resultant degradation products are biomass, carbon dioxide and water. Oxidatively degradable plastic: is a plastic in which the degradation results from the action of oxidation. Hydrolytically degradable plastic: a plastic in which the degradation results from hydrolysis.


According to the American Society for Testing and Materials (ASTM), polymers are biodegradable if degradation results from the action of naturally occurring micro-organisms such as bacteria, fungi, and algae. As we have seen, biodegradable polymers can be produced from natural materials such as starch and cellulose, as well as from polymers that are derived from petrochemical feedstocks. Biopolymers like polyester and starch-based polymers are being pushed as an environmentally friendly alternative to petroleum-based polymers, which may take hundreds of years to naturally biodegrade. Biopolymers can be produced without toxic by-products and biodegrade quickly, leaving a minimal human footprint on the environment. However, like the issue of degradability there is often confusion over the terms biopolymer, bioplastics and biodegradability. A bioplastic is made from a renewable natural biological polymer source (plant, animal or microorganism), however, materials are also available in the marketplace that have both bio-origin and petroleum based materials. Equally, materials may mix biopolymers with non-bioadditives. So while some materials may be 100% fully fledged biological plastic (including all the additives and the polymer), others may be a combination. A further confusion comes with the fact that just because a bioplastic has components of a biopolymer, it does not necessarily biodegrade as the original source material did. On the other hand a petroleum-based plastic such as PVAL is water soluble, but does not have the ‘green’ credentials often credited to bioplastics. Biopolymers can be made into any number of material types, such as thermoplastics, thermosets, elastomers, just like their oil-based counterparts. Therefore biopolymer, bioplastic and biodegradable are not the same thing and it should not be assumed (although mainly it does) that one necessarily follows from the other. PE can be produced from oil feedstocks, however, it can also be produced by using sugar. PE which has been produced by the sugar route is a biopolymer, that produced by oil is not. However, neither are biodegradable, though they can be made to degrade over time through the use of additives. This sort of controlled degradation of synthetic polymer is well known, especially for PE films. A biodegradable plastic is one which degrades through the action of nature. That is through naturally occurring organisms such as bacteria, algae and fungi. This mechanism could occur through mechanisms such as composting, soil burial, anaerobic digestion, marine and freshwater environments or exposed to the environment as litter.

The final option of the disposal of litter through biodegradation is attractive. The persistence of plastic products discarded in the environment is a major problem. The majority of these wastes come in the form of packaging which has a short life cycle. Therefore, biodegradable materials, especially in the packaging industry are becoming an important strategy for the future removal of plastic waste from our environment. There are currently three different types of biodegradable materials that can be readily identified in the marketplace: s # OMPOSTABLE PLASTICS SUCH AS 06!, AND polyethylene oxide). s " IOPLASTICS BASED ON RENEWABLE FEEDSTOCKS SUCH as maize, corn and starch which are biodegradable. (These will be discussed in more depths in Section 14.1). s 7ATER SOLUBLEPLASTICSn06!,

14.1 Biodegradable Plastics A biodegradable plastic has been defined in Section 14 as when the degradation is the result of naturally occurring microorganisms (e.g., algae, bacteria or fungi) and a compostable plastic as one in which the degradation also occurs by biological processes but in a specified composting environment (a.10, a.16). A number of different definitions of biodegradable plastics have been published by different organisations. However, most of the definitions of biodegradation are based on the same concept: the action of microorganisms on the material and its conversion into carbon dioxide or methane and water. For example, under EN 13432 (a.17) the scope of testing for packaging includes assessment of four factors. These are: Biodegradability, disintegration during biological treatment, the effect on the biological treatment process and the effect on the quality of the resultant compost. Some of the factors considered include: Before assessment materials must be characterised by their constituent parts including the presence of any heavy metals, volatile solids and the organic carbon content amongst others.

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Disintegration in a biological waste treatment process can be either aerobic or anaerobic but must occur without any detrimental affects on the process itself. For anaerobic biodegradation testing the maximum testing time can be 2 months, for an aerobic biodegrading test the maximum degradation exposure time is 6 months.

effects such as abrasion or mechanical impact. Since their effectiveness to degrade is effected by the intensity of the UV exposure, factors such as weather conditions and location are major factors in the process. Photodegradable plastics remain most useful in applications that remain problematic to littering an obvious example being plastic bags.

After degradation has occurred the compost would be sieved for residues and not more than 10% of the original dry weight of the material shall fail to pass through a < 2mm sieve fraction for an acceptable disintegration to have occurred.

However, it should be noted that while most synthetics do not naturally degrade in the environment at useful timescales, they can be made to be degrade much faster if this is required. Controlling this rate is another issue and one which is beyond the scope of this review. However photodegradation is an example of controlled degradation in action.

Composting plastics are required to leave no toxic residues, biodegradation is generally less specific. It is therefore important to consider degradation in light of the specific standards and test methods for the materials being considered.

15. Plastics and Biodegradable Plastics Disposal

14.2 Oil-Based Naturally Degradable Polymers As we have seen it is not only biopolymers than can degrade in the environment. Synthetic materials can be made to degrade by the use of additives or by being soluble in water. There are two main types of polymers in this category, PVAL and EVOH. Like PVAL, EVOH is also a water-soluble synthetic plastic and is commonly used in multilayer film packaging (film and blow moulding) in conjunction with cheaper materials as an oxygen barrier layer. It is a high cost material whose pricing presents a considerable barrier to expansion into the degradable plastic market.

Much of European environmental policy on plastics and biodegradable materials has come from European Union legislation. Environmental Action Programmes (EAP) have been in place for over 30 years now. There have been six versions which have developed increasingly as our understanding of environmental protection has advanced. Therefore from the first through to the current sixth EAP, increasing legislative requirements have been developed for the benefit of EU citizens.

14.3 Photo-degradable Plastics

However, a midterm report on the sixth EAP published in April 2006 stated that ‘the EU was still not yet on the path towards genuine sustainable development’. Therefore further legislation is still likely in waste management. In the context of this review, areas of interest to future markets of PVAL derive from tougher legislation in the areas of The Landfill Directive and Sustainable Development, both objectives in EAP 6.

A further type of the way plastics can be degraded is through the use of daylight. This is called photodegradability, The ultraviolet (UV) radiation present in daylight can be used to photodegrade synthetic polymers which contain suitable formulations. This type of degradation can therefore be triggered in polymers such as PE. By incorporating light sensitive materials into plastic formulations either through the use of copolymers or additives it is possible to induce bond breakage of the carbon backbone. Plastics left exposed to UV light, therefore, breakdown becoming increasingly weak and brittle as the bonding breaks down. This also makes the residual components more likely to degrade further from other environmental

For sustainable development the key themes is to promote both sustainable production and consumption. This should encourage the growth of environmental degradation as a waste disposal option. The EU intends to support research and encourage further adoption of Integrated Product Policy (IPP) programmes which are aimed at reducing environmental impact associated with particular products and services. Therefore, manufacturers in member states will be encouraged to reduce impact throughout the life cycle of their products. The EU has already adopted IPP philosophy is legislation which can be seen in both the End-ofLife (ELV) Vehicle Directive (a.18) and even more obviously in the WEEE Directive (a.8), however, these

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are sectors in which PVAL is not expected to have great impact in the foreseeable future. (Though given advances in material technology, applications such as PVAL mobile phone cases may one day be seen.) The 1999 EU Landfill Directive (Directive 1993/31/EC) which took a further three years to become transposed into English law, will have widescale implications for how plastic waste is disposed of in future, certainly within the UK which has been heavily reliant on this form of waste disposal. Biodegradable municipal waste going to landfill must be drastically reduced, dropping to just 35% of that produced in 1995 by 2020. Whilst this legislation is not aimed at just plastics but all materials, it is clear that disposal by other means, i.e., composting facilities, are being encouraged by such legislation. The waste management hierarchy is: 1. Prevention 2. Re-use 3. Recycling 4. Recovery (including energy recovery) 5. Safe disposal Therefore the sensible approach in dealing with plastic waste is to reduce the amount of waste at source. For waste already generated, control should be exercised over the life cycle from design, production and usage. For bioplastics, re-use and recycling will be less of an option as the preferred disposal would be for biomass production. However, this also throws up issues of energy usage as a durable oil-based plastic once produced may be recycled several times before being recovered for energy via incineration. A one use biopolymer would be made, used, and then discarded. These are issues which must be considered in adoption of these materials. Is it worth putting all that energy into making them to immediately discard them and turn them back to biomass? The type of biodegradable plastic employed for any application should dictate the disposal route. This may be by standard plastic reprocessing, landfill or open environments. A compostable material needs composting facilities and water soluable and/or water degradable materials need water or waste water treatments. Contamination of conventional plastics recycling routes could be a significant risk in future as biopolymers become more established in the market place. Consider the effect of a photodegradable HDPE on HDPE recyclate. It would remain undetected in feedstock and be recycled with non-degradable plastics.

However, once these materials are reused for example as containers, they would retain the potential to degrade and disintegrate under daylight. Consumers would not be too happy if their water butts or compost bins disintegrated. Therefore, widescale use of degradable plastics has the potential to undermine the growing confidence in recycled plastics. Effective methods for control of sorting degradable and non-degradable plastics will be necessary to ensure this does not happen if there is a significant change in degradable plastic usage. Labelling to inform consumers of where to dispose of their plastics is one such method, There are several identifiable environmental benefits that may potentially be derived from the use of biodegradable plastics compared to non-degradable plastics. These are: s #OMPOSTDERIVEDINPARTFROMBIODEGRADABLEPLASTICS such as PVAL increases the soil organic content as well as water and nutrient retention, while reducing chemical inputs and suppressing plant disease. s "IODEGRADABLE PLASTICS APPEAR TO OFFER IMPORTANT environmental benefits in many cases: the use of potentially sustainable resources and reduced greenhouse gas emissions. However, it should be remembered that there is potential for adverse environmental risks with biodegradable plastics. Despite their nature, they still require time in order to decompose completely. There are significant concerns that with current low levels of consumer education, biodegradable plastics may be seen as being suitable for disposal through any means available, and in some cases predictions are that littering will even rise as a result of their use and subsequent incorrect disposal. However, there are specific requirements regarding degradation, and indeed, in many cases the contamination of traditionally employed polymer waste streams with biomaterials is another considerable problem to be overcome. One potential method of resolving this issue is the development and implementation of some form of labeling or decoration to ensure consumers are aware of the correct disposal routes. A further consideration is that biodegradable plastics which end up in landfills may also prove problematic as they are unlikely to degrade under such highly packed conditions and could prove as persistent as standard plastics wastes in landfill sites. Furthermore, there is potential for methane to be released during the degradation process with some biopolymers which would clearly exacerbate global environmental issues.

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European legislation promoting sustainability will continue to be an important market driver. However, high costs relative to conventional plastics, concern about performance of biodegradable plastics, and limited production capacity have restricted market expansion to less than 1%. However, certainly in Europe, bioplastics are viewed as a large potential market for starch-based crops like corn, wheat, potatoes and peas. Currently, bioplastics applications account for only a few, serving mostly the low end loose fill packaging and high end surgical/medical devices and cosmetic packaging markets. However, if mandatory biodegradable regulations are enacted, the European markets could expand quickly. Consumer education on sustainability, recycling and degradability should be encouraged allowing the public to have a clear picture of the options available rather than the limited viewpoints that are expressed by national newspapers for instance. This will allow for a clearer determination of appropriate waste disposal methods such as composting, incineration and landfilling.

15.1 Composting Compost is the natural, aerobic (oxygen using) and exothermic (heat producing) process which occurs with the breakdown of organic matter derived from animals and plants. Bacteria, fungi, insects and animals which inhabit soil break down the material and as a result biomass/humus, carbon dioxide (or methane) and water are formed. The resulting biomass can then be used to facilitate further plant growth with the use of the soil like residues, which contain significant levels of useful bacteria and nutrients and the volume of organic waste sent to landfill is also reduced. For composting to become a major part of our waste disposal infrastructure a large number of commercial composting facilities will be required. Under waste management regulations these, like landfill sites, are likely to require licenses to ensure correct environmental standards are adhered to. It will also need a shift in the way waste is sorted. However, putting our plastic waste onto the compost heaps in our gardens may be some time away.

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15.2 Incineration Incineration, whilst not used as a major waste disposal option in the UK is the primary waste disposal route for a number of countries. Japan for example, where landfill space is limited, disposes of over 90% of its waste in this manner. Scandinavian countries also strongly favour this method of waste disposal over landfill. The reason is that the content of municipal waste including plastic wastes, are a good source of fuel. Plastics are made from oil reserves after all. Further, the energy created by incineration can be used to generate electricity and therefore this method of disposal is often termed energy recovery. Whole cities can be powered by burning wastes by this method. However, countries who favour land filling such as the UK, do not currently have the incinerator capacity available to make widescale switches in their waste disposal strategy. Modern technology ensures problems of emissions are minimised but often incinerators are of concern to the residents living nearby for fear of air pollution and new installations often therefore attract strong protests. Incineration does not eliminate all waste but substantially reduces it. The residues still need to be disposed of, usually by landfilling. Plastics disposed of by incineration leave no residue. However, the use of fillers and additives may reduce the energy produced as the polymer percentage is reduced. Western Europe generates around 100 million tonnes of solid waste annually of which around 7% is plastics. However new technologies for disposal are emerging for plastic materials with heat generation, most notably methods of pyrolysis which have been developed to recover chemical fractions of the plastics which can be used as fuels or chemical feedstocks. Reinforcements where present such as glass and carbon fibre can also be collected by similar methods. At present there are technologies for collecting the polymer and technologies for collecting the fibre but not as yet, a single combined solution. However, research is ongoing in this area of materials recovery. For thermoset materials, which cannot be recycled, this could be the most appropriate method of future waste disposal. The strength and durability of thermoset composite materials makes them highly unlikely to be replaced by biopolymer composites in the near future.


15.3 Landfilling In the UK landfilling has been the principal means in which waste has been handled (over 80% of our waste goes to landfill), this is in contrast to some other European countries that favour incineration (with energy recovery) to dispose of their waste. However, following EU legislation, namely the EU Landfill Directive, strategies for diverting biodegradable municipal waste from landfill must be implemented. Because of the reliance on landfilling in the UK, they were given four years longer to implement the targets (an offer extended to all EU Member States land filling at levels over 80%). Waste considered hazardous, non hazardous and inert must be separated by landfill operators and a single site can only be licensed to accept one type of waste. Landfill operators are also, as of October 2007, required to treat non-hazardous waste. This can include any biological, chemical, physical or thermal process which reduces volume or hazard. This can include sorting, to encourage recycling or energy recovery. The underlying principles of landfill operation remain the same: to prevent or reduce negative effects of land filling which threaten either the environment or human health.

16. Conclusion PVAL is unique among synthetic polymers. Although made from oil-based feedstock, this polymer has an inherent ability to be biodegraded. With properties once regarded as a scientific curiosity and a niche market which utilises its inherent water solubility and with biocompatibility and biodegradable credentials, this material is likely to expand further into markets in which biopolymers and biodegradable materials (namely short life consumer products and medical applications) are likely to dominate in future. With biodegradable plastics materials likely to become more valuable as land fill operations seek to divert such waste, it is unclear how this may affect the prospects for biodegradable plastics in the marketplace unless prices become more commercially comparable with traditional commodity plastics. Blending of materials may provide one method to limit the cost penalties but the wide scale implications for waste disposal and expanding recycling

capacity if such materials are used is also uncertain. However with increasing pressure for sustainability to be bought to bare from the EU, significant shifts both in the marketplace and disposal infrastructure will have to occur to meet the waste targets.

References a.1

BS EN ISO 15023-1, Plastics - Poly(vinyl alcohol) PVAL Materials - Part 1: Designation System and Basis for Specification, 2006.

a.2

DIN 53015, Viscometry - Measurement of viscosity by means of the rolling ball viscometer by Hoppler, 2001.

a.3

Japan Chemical Week, 2006, 47, No.2385, 8.

a.4

N. Preston, Flexible, 2006, 4, 5, 40.

a.5

M. Kokabi, M. Sirousazar and Z.M. Hassan, European Polymer Journal, 2007, 43, 3, 773.

a.6

F.F. Nord, Naturwiss 1936, 24, 763.

a.7

E. Chiellini, A. Corti, S. D’Antone and R. Solaro, Progress in Polymer Science, 2003, 28, 963.

a.8

The European Directive on WEEE (Directive 2002/96/EC)

a.9

Plastics Technology, 2004, 50, 10, 32.

a.10

Plastics Technology, 2007, 53, 2, 60.

a.11

ASTM D882, Test Method for Tensile Properties of Thin Plastic Sheeting, 2002.

a.12

ASTM D1004, Test Methods for Tear Resistance (Graves Tear) of Plastic Film and Sheeting, 2008.

a.13

ASTM D5226, Practice for Dissolving Polymer Materials, 2003.

a.14

E.R. Kenaway P. Cinelli A. Corti S. Miertus and E. Chiellini, Macromolecular Symposia, 1999; 144, 351.

a.15

K. Pal, A.K. Banthia and D.K. Majumdar, AAPS PharmSciTech, 2007, 8, 1, Article 21.

a.16

A. Srivastava, Popular Plastics and Packaging, 2004, 49, 1, 87.

a.17

EN13432, Packaging - Requirements for Packaging Recoverable Through Composting

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and Biodegradation - Test Scheme and Evaluation Criteria for the Final Acceptance of Packaging, 2005. a.17

G. Scott, Polymer Degradation and Stability, 2000, 68, 1.

a.18

End-of-Life Vehicle (ELV) Directive [Directive 2000/53/EC]

a.18

M. Heyde, Polymer Degradation and Stability, 1998, 59, 1-3, 3.

a.19

R.Chandra and R. Rustgi, Progress in Polymer Science, 1998, 23, 1273.

a.20

P. Nayak, Review of Macromolecular Chemistry and Physics, 1999, 39, 3, 481.

Abbreviations and Acronyms ASTM CRT EAP ELV EU EVOH HDPE IPP LCA LCD LDPE LLDPE OPP PA PBS PCL PDP PE PET PHA PHB PHBV PLA PP PVAc PVAL PVB PVC PVDC TPS UV

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American Society of Testing and Materials Cathode ray tube(s) Environmental Action Programme(s) End-of-life vehicle European Union Ethylene vinyl alcohol High-density polyethylene Integrated product policy Life cycle analysis(es) Liquid crystal display(s) Low-density polyethylene Linear low-density polyethylene Orientated polypropylene Polyamide Polybutylene succinate Poly-E-caprolactone Plasma display panel(s) Polyethylene Polyethylene terephthalate Polyhydroxyalkonoates Polyhydroxybutyrate Poly(hydroxybutyrate-cohydroxylvaleratevalerate) Poly(lactic acid) Polypropylene Polyvinyl acetate Poly(vinyl alcohol) Poly(vinyl butyral) Polyvinyl chloride Poly(vinylidene chloride) Thermoplastic starch Ultraviolet

References and Abstracts

Abstracts from the Polymer Library Database Item 1 Advanced Functional Materials 18, No.19, 2008, p.2946 SURFACTANT-FREE SELF-ASSEMBLED PVA-IRON OXIDE/SILICA CORE-SHELL NANOCARRIERS FOR HIGHLY SENSITIVE MAGNETICALLY CONTROLLED DRUG RELEASE AND ULTRAHIGH CANCER CELL UPTAKE EFFICIENCY Hu S-H; Liu D-M; Tung W-L; Liao C-F; Chen S-Y The synthesis of surfactant-free self-assembled poly(vinyl alcohol)(PVA)-iron oxide/silica core-shell nanocarriers by encapsulation of monodispersed magnetic iron oxide particles derived by high temperature decomposition of ferric acetylacetonate and a model hydrophobic drug such as ibuprofen using PVA as binder followed by coating with a thin shell of silica by hydrolysis and condensation of tetraethyl orthosilicate is described. The products were characterised by FE-SEM TEM SQUID magnetometry and XRD and their controlled drug release properties under an external magnetic field were investigated by UV-visible spectroscopy. 28 refs. Taiwan National Chiao Tung University TAIWAN

Accession no. 1030215 Item 2 Advanced Functional Materials 18, No.19, 2008, p.2855 A NOVEL CROSS-LINKED POLY(VINYL ALCOHOL) (PVA) FOR VASCULAR GRAFTS Chaouat M; Le Visage C; Baille W E; Escoubet B; Chaubet F; Mateescu M A; Letourneur D The fabrication of crosslinked poly(vinyl alcohol)(PVA) films by aqueous solution casting in the presence of sodium trimetaphosphate as crosslinking agent and their characterisation by DMA and by biocompatibility via cell culture studies is described. The fabrication of small diameter tubes based on the crosslinked PVA films via a gluing procedure with cyanoacrylate adhesive was investigated and their evaluation as potential vascular grafts by in-vitro and in-vivo testing is discussed in terms of mechanical properties such as compliance elasticity and resistance to mechanical stress compatible with circulatory blood flow. 31 refs. INSERM; Montreal University; Paris VII Universite; Paris XIII Universite CANADA; EUROPEAN COMMUNITY; EUROPEAN UNION; FRANCE; WESTERN EUROPE

Accession no. 1030209

© Copyright 2008 Smithers Rapra Technology

Item 3 Polymer 49, No.21, 2008, p.4740 TRANSITION OF HYDRATION STATES OF POLY(VINYL ALCOHOL) IN AQUEOUS SOLUTION Wenbo Li; Yun Zheng; Rongshi Cheng A straightforward method for determination of the hydration number of polymer in aqueous solution based on ice-melting technique of DSC is proposed. The simple yet precise method has been applied to determine the hydration number of poly(vinyl alcohol) (PVA) in aqueous solution covering a wide range of concentrations from 0.005 to 0.3 g(solute)/g(solution) for three samples with different molar masses. The hydration number of PVA maintains a constant lower value of 2.5 when the concentration exceeds 0.2 g(solute)/g(solution). It increases to a value of 7 when the concentration decreases to the overlap concentration C*of the polymer where C*was estimated as the reciprocal of its intrinsic viscosity. For solutions of C300 times) perhaps due to surface pinning of the entanglement network. The compliance increases as approximately the square of film thickness. 10 refs. USA

Accession no. 982360 Item 145 Proceedings of the 64th SPE Annual conference (ANTEC 2006) held Charlotte, NC p.1366 ELECTROSPUN PVA FIBERS AS PRECURSOR TO SYNTHESIZE HYDROXYAPATITE Dai X; Shivkumar S PVA (Polyvinyl alcohol) with various molecular weights (Mw) were electrospun with a Calcium Phosphate based sol. Fibres on the order of 2 mum with uniformly distributed sol particles were obtained. Electrospinning process may be facilitated with high molecular weight polymers. The distribution of sol in the electrospun structure may depend on polymer/sol ratio. XRD results indicate that the fibres after calcination consisted predominantly of hydroxyapatite. 20 refs. EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE Accession no. 982337 Item 146 ACS Polymeric Materials: Science and Engineering. Spring Meeting 94, 2006, p.685 MODIFICATION OF CEMENT MORTARS BY DIFFERENT POLYMER LATEXES AND CURING PROCESSES Bing Geng; Shuxiang Zhang; Pandeng Xia; Xiang Z Kong Cement mortars were prepared with three different polymer latices. Latices were prepared by emulsion polymerisation from vinyl acetate vinyl acetate and acrylic acid and chlorotrifluoroethylene (CTFE) and vinyl acetate. Polymer mortars were compared for their flexural and compression strengths and were examined using

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scanning electron microscopy. The fluorinated polymer gave the best reinforcement. Further mortars with different fluoropolymer contents were prepared and cured in air and in water. The air cured product proved to have the best performance. 8 refs. CHINA

Accession no. 981986 Item 147 Journal of Applied Polymer Science 102, No.5, 2006, p.4831 PREPARATION OF HIGH-MOLECULARWEIGHT POLY(VINYL ALCOHOL) WITH HIGH YIELD BY SOLUTION POLYMERIZATION OF VINYL ACETATE IN METHANOL USING 44'AZOBIS(4-CYANOVALERIC ACID Lyoo W S; Song D H; Lee W C; Han S S; Noh S K The effects of polymerisation temperature and initiator concentration on the polymerisation of vinyl acetate (VAc) was in methanol solution at 40 deg.C and 50 deg.C using 4,4'-azobis(4-cyanovaleric acid) (ACVA) as an initiator. The lower rate of polymerisation obtained by using ACVA and the lower viscosity of methanolic solutions resulted in the production of linear highmolecular weight (HMW) poly(vinyl acetate) (PVAc) with a high conversion. Poly(vinyl alcohol) (PVA) with a maximum number-average degree of polymerisation (Pn) of 4300 could be prepared by saponification of PVAc with a maximum Pn of 7900 obtained by polymerisation at an ACVA concentration of 2 x 10-5 mol/mol of VAc at 40 deg.C. Moreover a degree of branching of below 1 could be obtained by using the ACVA system at 40 or 50 deg.C. This suggests an easy way for producing HMW PVA with a high yield by conventional solution polymerisation without the use of special methods such as low-temperature cooling or irradiation. 13 refs. Yeungnam University; Kyungil University SOUTH KOREA

Accession no. 981789 Item 148 Journal of Applied Polymer Science 102, No.5, 2006, p.4665 SWELLING OF PH-SENSITIVE CHITOSANPOLY(VINYL ALCOHOL) HYDROGELS Gunasekaran S; Wang T; Chai C The swelling properties of chitosan-poly(vinyl alcohol) (PVA) hydrogels were investigated as functions of the pH and salt concentration of the medium. Maximum swelling of the hydrogels occurred at a buffer pH of approximately 3 regardless of the PVA content in the hydrogels. The maximum mass of the swollen hydrogels was about 13 times that of the contracted counterparts. Cyclic swelling and contraction between pH 3 and pH 7 buffers and between pH 3 buffer and pH 3 buffer plus salt confirmed that the hydrogels swell by a Donnan mechanism. The



swelling mechanism involves transfer of water molecules driven by a concentration gradient. The effective masstransfer coefficient of water molecules during swelling estimated by means of a model gradually decreased with increasing PVA content in the hydrogels. 20 refs. Madison University of Wisconsin; Tianjin University CHINA; USA

Accession no. 981768 Item 149 Journal of Power Sources 162, No.1, 2006, p.21 DEVELOPMENT OF ALKALINE DIRECT METHANOL FUEL CELLS BASED ON CROSSLINKED PVA POLYMER MEMBRANES Chun-Chen Yang; Shwu-Jer Chiu; Wen-Chen Chien

Kashan University; Amirkabir University IRAN

Accession no. 981096 Item 151 Chemical Engineering Science 61, No.10, 2006, p.3149 GROWTH CONTROL OF ICE CRYSTALS BY POLY(VINYL ALCOHOL) AND ANTIFREEZE PROTEIN IN ICE SLURRIES Inada T; Modak P R

TAIWAN

Effect of poly(vinyl alcohol) (PVA) in inhibiting an increase in ice crystal size in isothermal ice slurries was investigated and then compared with the effect of an antifreeze protein (AFP) NaCl and three other polymers namely poly(ethylene glycol) poly(vinyl pyrrolidone) and poly(acrylic acid). First ice slurries in which the initial size distribution of ice crystals was known were isothermally preserved for given periods of time (typically 300min) in the presence of PVA AFP type I NaCl or the other three polymers. Then the average size of the ice crystals was measured using image processing. Both the PVA and AFP type I completely inhibited the increase in ice crystal size at such low concentrations that the melting temperature of the solution was -0.010 deg.C whereas NaCl and the other three polymers clearly increased the ice crystal size due to Ostwald ripening. This inhibition effect of PVA and AFP type I was caused by thermal hysteresis which is often taken as the primary manifestation of non-equilibrium antifreeze activity of these additives and defined as the difference between the melting temperature and nonequilibrium freezing temperature at which ice crystals start to grow in solution. The increase in ice crystal size was inhibited when the thermal hysteresis surpassed the driving potential for Ostwald ripening. Using PVA which exhibits thermal hysteresis is a novel technique to completely inhibit the increase in ice crystal size in isothermal ice slurries. 36 refs. AIST


JAPAN

A novel crosslinked PVA/SSA (10 wt% sulphosuccinic acid) solid polymer membrane was obtained by a solution casting technique. An alkaline direct methanol fuel cell (DMFC) is composed of an air cathode with a mixture of Mn O2/BP2000+CNT binary carbon inks a Ti-based anode electrode with PtRu black inks (varied from 0.25 to 4.50 mgcm-2) and an alkaline crosslinked PVA/SSA solid polymer membrane. The electrochemical characteristics of the anode and cathode electrodes were investigated by the linear polarisation method cyclic voltammetry (CV) analysis potentiostatic method and AC impedance spectroscopy. A Ti-mesh (Delker) with a thickness of 0.1 mm was used as a current collector on the anode electrode without a diffusion layer which greatly reduced the mass transfer resistance for the electrode reaction. It was demonstrated that the alkaline DMFC using this novel crosslinked PVA/SSA solid polymer membrane showed excellent electrochemical performance at ambient temperature and pressure. The maximum peak current density of the DMFC was about 4.13 mW/cm2 at 60 deg.C and 1 atm in 2M KOH+2M CH3OH solution. 38 refs. Mingchi University of Technology

Accession no. 980482 Item 150 Journal of Adhesion Science and Technology 20, No.12, 2006, p.1273 VISCOMETRIC STUDY OF AQUEOUS POLY(VINYL ALCOHOL) (PVA) SOLUTIONS AS A BINDER IN ADHESIVE FORMULATIONS Mohsen-Nia M; Modarress H The viscosities of aqueous PVAl solutions were measured using an Ostwald viscometer and the data obtained fitted to a modified version of Eyring's viscosity model developed by the authors. The densities of the PVAl solutions and average molec.wts. of the PVAl required for viscosity calculations were determined and the densities expressed by a simple linear equation in terms of PVAl weight fraction. 20 refs.


Item 152 Journal of Membrane Science 276, No.1-2, 2006, p.42 CERAMIC-SUPPORTED THIN PVA PERVAPORATION MEMBRANES COMBINING HIGH FLUX AND HIGH SELECTIVITY; CONTRADICTING THE FLUX-SELECTIVITY PARADIGM Peters T A; Poeth C H S; Benes N E; Buijs H C W M; Vercauteren F F; Keurentjes J T F Thin high flux and highly selective cross-linked poly(vinyl)alcohol water selective layers have been prepared on top of hollow fibre ceramic supports. The supports consist of an alpha-Al2O3 hollow fibre substrate

61


and an intermediate gamma-Al2O3 layer which provides a sufficiently smooth surface for the deposition of ultrathin PVA layers. Membranes have been characterised by SEM and pervaporation experiments. The thickness of the PVA layer formed on top of the gamma-Al2O3 intermediate layer is in the order of 0.3-0.8μm. No significant infiltration of PVA into the intermediate gamma-Al2O3 layer can be observed. In the dehydration of 1-butanol (80 deg.C 5wt.% water) the membranes exhibit a high water flux (0.8-2.6kg/m2/h) combined with a high separation factor (500-10000). The values for the flux and separation factor exceed typical values obtained for cross-linked PVA membranes on polymeric supports. In the dehydration of 2-propanol and 1-butanol a simultaneous increase in both water flux and separation factor is observed with increasing temperature or water concentration. This remarkable behaviour is in contrast to the trade-off generally observed for polymer membranes i.e. an increase in flux is typically combined with a decrease in separation factor. A possible explanation for this behaviour is a low degree of three-dimensional swelling in the vicinity of the gamma-Al 2O 3-PVA interface due to an enhanced structural stability. In the dehydration of ethanol and 1-propanol the traditional trade-off between flux and selectivity was observed. 21 refs. Eindhoven University of Technology; TNO Science and Industry EUROPEAN COMMUNITY; EUROPEAN UNION; NETHERLANDS; WESTERN EUROPE

Accession no. 980457 Item 153 Journal of Applied Polymer Science 102, No.4, 2006, p.3934 RHEOLOGICAL PROPERTIES OF HIGH MOLECULAR WEIGHT (HMW) SYNDIOTACTIC POLY(VINYL ALCOHOL) (PVA)/HMW ATACTIC PVA BLEND SOLUTIONS Lyoo W S; Yeum J H; Kwon O W; Shin D S; Han S S; Kim B C; Jeon H Y; Noh S K Water-soluble syndiotactic-poly(vinyl alcohol) (s-PVA) and atactic-PVA with syndiotactic diad contents of 58.5 and 54.0% respectively were prepared by bulk copolymerisation of vinyl pivalate and vinyl acetate (VAc) and by solution polymerisation of VAc to give poly(vinyl pivalate-co-vinyl acetate) and poly(vinyl acetate) respectively which were then subjected to saponification. At frequencies of 10-1 to 102 rad/s s-PVA/a-PVA blend solutions with larger s-PVA contents showed more shear thinning suggesting that PVA molecules become more readily oriented as the s-PVA content is increased. The yield stress was also higher for s-PVA/a-PVA blend solutions with larger s-PVA contents suggesting that more domains with an internal order are produced at higher s-PVA contents in the s-PVA/a-PVA blend solutions. 25 refs.

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Yeungnam University; Kyungpook National University; Hanyang University; Inha University SOUTH KOREA

Accession no. 979602 Item 154 Journal of Applied Polymer Science 102, No.4, 2006, p.3273 RED EMISSION FROM EU3+: PVA POLYMER FILM Raju G S R; Buddhudu S; Rajulu A V Bright-red luminescent films of Eu3+-doped poly(vinyl alcohol) (PVA) were produced by solution casting. The emission performance of these films was studied by measurements of excitation emission and lifetimes. The doped films emitted bright-red light on irradiation with a UV source. Emission processes in the system was explained by an energy-level scheme. 25 refs. Anantapur S.K.University INDIA

Accession no. 979521 Item 155 Journal of Membrane Science 283, No.1-2, 2006, p.281 CORRELATION OF PHYSICOCHEMICAL CHARACTERISTICS WITH PERVAPORATION PERFORMANCE OF POLY(VINYL ALCOHOL) MEMBRANES Hyder M N; Huang R Y M; Chen P In this research hydrophilic poly(vinyl alcohol) PVA membranes were prepared and its surface and bulk properties e.g. surface roughness and crosslinking were characterized using Fourier transform infrared (FTIR) spectroscopy atomic force microscopy (AFM) and differential scanning calorimetry (DSC) and contact angle measurements. The PVA membranes were crosslinked in two ways: by heating at 125 deg.C or by chemical reaction with glutaraldehyde at room temperature. They were used for pervaporation applications and dehydration of ethanol-water mixture was demonstrated in this paper. Compared to non-crosslinked membranes the crosslinked membranes were shown to change in chemical structure by FTIR and become less hydrophilic by water contact angle measurement. The contact angle of the membranes increases with increasing the glutaraldehyde concentration used in crosslinking solution. AFM surface scans showed that the membrane surfaces are rough in nanometer scale and affected by the crosslinking treatment on the membranes. DSC measurements showed an increase in melting temperature of the polymer membranes after crosslinking. Dehydration of ethanol-water mixture was conducted over a range of ethanol concentrations (1070wt.%) in feed solution and at varied temperatures (from 25 to 50 deg.C). The dehydration results are presented and correlated with the results of the physicochemical measurements of the membranes. 35 refs.



Waterloo University CANADA

Accession no. 979273 Item 156 Journal of Applied Polymer Science 102, No.3, 2006, p.2315 PREPARATION AND CHARACTERIZATION OF PVA/OMMT COMPOSITES Yurudu C; Isci S; Unlu C; Atici O; Ece O I; Gungor N Composites of poly(vinyl alcohol) (PVA) with organically modified montmorillonite (MMT) were prepared and characterised. MMT dispersions were modified by the addition of various concentrations of hexadecylamine (HDA) to a 2 wt% montmorillonite dispersion. The basal spacing of the resulting organoclay was studied by X-ray diffraction. FTIR spectroscopy revealed the presence of characteristic absorbencies after treatment with HDA. The HDA/MMT/PVA composites were prepared by treatment of a 1 wt% PVA solution with the MMT/HAD organoclay complex and characterised by a range of techniques. The effect of the solids content on the rheological behaviour of aqueous MMT dispersions was also examined. 21 refs. Istanbul Technical University TURKEY

Accession no. 978405 Item 157 Polymers and Polymer Composites 14, No.6, 2006, p.577 NEW BIODEGRADABLE BLENDS FROM ALIPHATIC POLYCARBONATE AND POLY(VINYL ALCOHOL) Cao Y X; Du F G; Wang X L; Meng Y Z Blends of biodegradable polymers based on polypropylene carbonate and polyvinyl alcohol were prepared by solution casting. Various blend ratios were investigated with reference to thermal and mechanical properties and morphology. Thermogravimetric analysis DSC static mechanical measurements SEM and FTIR techniques were used to characterise the blends. Polypropylene carbonate/ polyvinyl alcohol blends (PPC/PVA) with a 10% PVA and 40% PVA ratio were found to be miscible systems but PPC/20% PVA and PPC/30% PVA blends were found to be two-phase systems. Both tensile strength and modulus increased with increasing PVA content due to a strong interaction between the PPC and PVA phases through hydrogen bonding. Blending PVA with PPC was shown to provide an effective way to increase both the thermal stability and mechanical properties of polypropylene carbonate. 16 refs Sun Yat-Sen University CHINA



Item 158 Materials Research 9, No.2, 2006, p.185 SYNTHESIS AND CHARACTERIZATION OF POLY(VINYL ALCOHOL) HYDROGELS AND HYBRIDS FOR RMPB70 PROTEIN ADSORPTION Dos Reis E F; Campos F S; Lage A P; Leite R C; Heneine L G; Vasconcelos W L; Lobato Z I P; Mansur H S The synthesis of hydrogels of poly(vinyl alcohol)(PVA) crosslinked with glutaraldehyde with or without the addition of tetraethylorthosilicate and their hybrids with recombinant MPB70 protein and their characterisation by FTIR is described. The application of the PVA hydrogels and hybrids for immunological assay using enzyme-linked immunosorbent assay (ELISA) techniques and the results are discussed in terms of protein adsorption. 26 refs. Minas GeraisUniversidade Federal; Minas GeraisFundacao Ezequiel Dias BRAZIL

Accession no. 977263 Item 159 Journal of Applied Polymer Science 102, No.2, 2006, p.1553 ALGINATE-POLY(VINYL ALCOHOL) CORESHELL MICROSPHERES FOR LIPASE IMMOBILIZATION De Queiroz A A A; Passos E D; Alves S De B; Silva G S; Higa O Z; Vitolo M Triacylglycerol ester hydrolase (EC 3.1.1.3) was encapsulated in microspheres of sodium alginate (AlgNa) and poly(vinyl alcohol) (PVA). Spherical AlgNa/PVA beads with an average diameter of 400 microns were prepared by ionotropic gelation of an AlgNa/PVA blend in the presence of calcium tetraborate. The increased glass-transition temperature of the microspheres indicated specific crosslinking of the component polymers. The water diffusion coefficients increased with increasing PVA content in the microspheres indicating a decrease in the resistance to mass transfer through the AlgNa/ PVA microsphere wall. The Michaelis constant and the maximum reaction velocity for the free and immobilised lipase showed that affinity of the enzyme for the substrate remained high after immobilisation in the microspheres. 33 refs. Itajuba Universidade Federal; BrazilInstituto de Pesquisas Energeticas e Nucleares; Sao Paulo University BRAZIL

Accession no. 977109 Item 160 Journal of Applied Polymer Science 102, No.2, 2006, p.1152

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DEHYDRATION OF TETRAHYDROFURAN BY PERVAPORATION USING CROSSLINKED PVA/ PEI BLEND MEMBRANES Rao P S; Sridhar S; Krishnaiah A

Egypt National Centre for Radiation Res.& Technol.

Dense membranes suitable for the dehydration of tetrahydrofuran (THF) by pervaporation were prepared by blending hydrophilic poly(vinyl alcohol) (PVA) and poly(ethyleneimine) (PEI) and crosslinking with glutaraldehyde (GA) in a mixture of solvents containing hydrochloric acid as a catalyst. The membranes were potentially useful for separating the THF/water azeotrope (94 wt%) and produced fluxes of 1.072 and 0.376 kg/m2 h and selectivities of 156 and 579 for plain and crosslinked PVA/PEI respectively. The selectivity improved with decreasing water concentration in the feed and with increasing membrane thickness whereas the flux decreased correspondingly. A high permeate pressure produced a reduction in both the flux and selectivity. These effects were explained in terms of known relationships between the plasticisation effect degree of swelling permeate pressure and feed water concentration. 43 refs.

Item 162 Journal of Applied Polymer Science 102, No.2, 2006, p.1014 EFFECT OF MOLECULAR WEIGHT ON DIELECTRIC PROPERTIES OF POLYVINYL ALCOHOL FILMS Joshi G; Pawde S M

Sri Venkateswara University; Indian Institute of Chemical Technology INDIA

EGYPT


Impedance analysis was performed on films prepared from poly(vinyl alcohol) (PVA) films with two different molecular weights. The dielectric polarisation of PVA film was measured at normal temperatures and pressures over the frequency range 20 Hz to 1 MHz. The effects of simultaneous application of DC bias potential from 0 to 40 V with AC signal for measurement of over all electrical parameters were examined. The dielectric constant of low-molecular weight PVA film were higher than those for high-molecular weight PVA in agreement with the Maxwell-Wagner theory. 12 refs. Mumbai Watumull Institute of Technology; Mumbai University Institute of Chemical Technology INDIA



Item 161 Journal of Applied Polymer Science 102, No.2, 2006, p.1129 ELECTRON BEAM SYNTHESIS AND CHARACTERIZATION OF POLY(VINYL ALCOHOL)/MONTMORILLONITE NANOCOMPOSITES Abd Alla S G; El-Din H M N; El-Naggar A W M

Item 163 Plastic Packaging Innovation News 2, No.16, 2006, p.6 TYPICAL PROPERTIES OF PVOH FILMS COMPARED TO OTHER TRADITIONAL FILM MATERIALS

Nanocomposites of poly(vinyl alcohol) (PVA) and montmorillonite clay (MMT) in the form of films were prepared by means of electron-beam irradiation. A 20kGy dose electron beam irradiation was optimal for producing homogeneous nanocomposites films with the highest degree of gel formation. The introduction of up to 4 wt% of MMT resulted in an improvement in the tensile strength elongation at break and thermal stability of the PVA matrix. The intercalation of PVA with the MMT also led to a markedly improved water resistance indicating that the clay was well dispersed in the polymer matrix. The intercalation had no effect on the metal uptake capability of PVA. X-ray diffraction patterns and scanning electron micrographs showed the coexistence of exfoliated intercalated MMT layers over the range of MMT contents studied. DSC thermograms showed that intercalation of the PVA polymer with these levels of MMT had no effect on melting transitions but the glass transition temperature for PVA completely vanished even at low contents of MMT. 24 refs.

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A table is presented listing properties of PVAL cellophane PVC and PE films including clarity gloss water vapour transmission tear strength tensile strength and elongation at break. WORLD

Accession no. 977005 Item 164 Polymer 47, No.19, 2006, p.6868 PURE SHEAR DEFORMATION OF PHYSICAL AND CHEMICAL GELS OF POLY(VINYL ALCOHOL) Urayama K; Ogasawara S; Takigawa T Pure shear deformation reveals the significant differences in elastic properties of the poly(vinyl alcohol) (PVA) gels with almost identical initial modulus but with different types of crosslinks physical crosslinks formed by microcrystallites and chemical crosslinks made of covalent bonds. The ratio of the two principal stresses steeply increases with elongation in the physical gels while that remains almost constant independently of stretching



in the chemical gels. The marked growth of the stress ratio with elongation in the physical gels leads to the negative values of the derivative of the elastic free energy (W2) with respect to the second invariant of the deformation tensor in the whole range of deformation which is firstly observed for elastomeric materials. By contrast the chemical gels exhibit the positive values of W2 like most chemically crosslinked rubbers. Among the existing theories of rubber elasticity the classical non-Gaussian three-chain model considering the effect of finite chain-length is qualitatively successful in accounting for the steep increase of the stress ratio and the negative values of W2 in the physical gels although it fails to reproduce the large difference in the stress-strain behaviour among uniaxial pure shear and equi-biaxial deformations. These features of the physical gels are expected to stem from the structural characteristics such as fewer amounts of slippery-trapped entanglement along network strands compared to the chemical PVA gels. 27 refs. Kyoto University JAPAN

Accession no. 976860 Item 165 European Polymer Journal 42, No.9, 2006, p.2013 A NANOFIBROUS COMPOSITE MEMBRANE OF PLGA-CHITOSAN/PVA PREPARED BY ELECTROSPINNING Duan B; Yuan X; Zhu Y; Zhang Y; Li X; Zhang Y; Yao K Tissue engineering scaffolds produced by electrospinning feature a structural similarity to the natural extracellular matrix. In this study poly(lactide-co-glycolide) (PLGA) and chitosan/poly(vinyl alcohol) (PVA) were simultaneously electrospun from two different syringes and mixed on the rotating drum to prepare the nanofibrous composite membrane. The composite membrane was crosslinked by glutaraldehyde vapour to maintain its mechanical properties and fibre morphology in wet stage. Morphology shrinkage absorption in phosphate buffered solution (PBS) and mechanical properties of the electrospun membranes were characterized. Fibroblast viability on electrospun membranes was discussed by MTT [3-(45-dimethylthiazol2-yl)-25-diphenyl tetrazolium bromide] assay and cell morphology after 7days of culture. Results indicated that the PBS absorption of the composite membranes no matter crosslinked or not was higher than the electrospun PLGA membrane due to the introduction of hydrophilic components chitosan and PVA. After crosslinking the composite membrane had a little shrinkage after incubating in PBS. The crosslinked composite membrane also showed moderate tensile properties. Cell culture suggested that electrospun PLGA-chitosan/PVA membrane tended to promote fibroblast attachment and proliferation. It was assumed that the nanofibrous composite membrane of electrospun PLGA-chitosan/PVA could be potentially used for skin reconstruction. 36 refs.


Tianjin University; Tianjin Hospital CHINA

Accession no. 976782 Item 166 Journal of Membrane Science 280, No.1-2, 2006, p.802 ALKALINE ZN-AIR AND AL-AIR CELLS BASED ON NOVEL SOLID PVA/PAA POLYMER ELECTROLYTE MEMBRANES Wu G M; Lin S J; Yang C C High ionic conducting solid polymer electrolyte membranes (SPEM) had been successfully prepared from poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA). The solution casting method yielded highly hydrophilic membranes with uniform structure that were suitable for electrochemical applications. The room temperature ionic conductivity of the alkaline PVA/PAA polymer electrolyte membranes was in the range of 0.142-0.301S/cm-1 depending on the composition. The cyclic voltammetry analysis was carried out using Zn|SPEM|Zn and Al|SPEM|Al cells. The analysis results revealed the excellent electrochemical stability of these newly developed alkaline solid PVA/ PAA polymer electrolyte membranes. Metal-air fuel cells were also prepared from the alkaline solid PVA/PAA polymer electrolyte membranes. The electrochemical cell performance was evaluated based on Zn-air and Al-air cells at C/10 and C/5 discharge rates. The experimental results exhibited high percent of utilisation for metal powders at room temperature. It was up to 90% for Zn-air cell when assembled with PVA:PAA=10:7.5 polymer electrolyte membrane and discharged at C/10 rate. The power density could be as high as 50mMW/cm2 at room temperature. However the cell percent utilisation was reduced to 73% with the same composition electrolyte membrane when C/5 discharge rate was tested. 16 refs. TAIWAN Taiwan Chang Gung University; Taipei Ming Chi University of Technology TAIWAN

Accession no. 975661 Item 167 Polymer Preprints 2005, 46, No.1, p.632 EFFECT OF PLASTICIZER ON PVAC-D3 DYNAMICS USING DEUTERIUM SOLID STATE NMR Nambiar R R; Blum F D The effect of dipropylene glycol dibenzoate plasticiser on the glass-transition temperature (Tg) of poly(vinyl acetate) was studied by deuterium solid-state NMR. The Tg of various plasticised samples was determined as the temperature where the NMR spectra collapsed into a broad single peak. For an unplasticised sample this occurred at between 65 and 70 deg.C and was roughly centred at 68 deg.C. The Tg of the plasticised polymer decreased with

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increasing plasticiser content and was 49 deg.C for a sample containing 20% plasticiser. 7 refs. USA

Accession no. 974688 Item 168 Journal of Applied Polymer Science 101, No.5, 2006, p.3493 PREPARATION AND ELECTRORESPONSIVE PROPERTY OF POLY(VINYL ALCOHOL)/ SODIUM ALGINATE COMPOSITE HYDROGEL Li R X; Zhang X Z; Zhao J S; Wu J M; Guo Y; Guan J A composite hydrogel of poly(vinyl alcohol) (PVA) and sodium alginate was prepared repeatedly freezing and thawing mixed solutions of PVA and sodium alginate. The composite hydrogel in aqueous NaCl solution showed swelling contraction and bending behaviour in the presence of a dc electric field. The bending speed and maximum degree of bending increased with increasing electric field intensity and NaCl solution concentration. The maximum degree of bending increased with increasing sodium alginate content in the composite hydrogel. 18 refs.TAIWAN Tianjin Institute of Medical Equipment; Tianjin Polytechnic University TAIWAN

Accession no. 972860 Item 169 Journal of Applied Polymer Science 101, No.5, 2006, p.3040 THERMALLY STIMULATED DEPOLARIZATION CURRENT BEHAVIOR OF POLYETHYLENE/ POLY(VINYL ACETATE) BLENDS: EFFECT OF BLENDING Choure C; Keller J M; Bajpai R Thermally stimulated depolarisation currents (TSDCs) in polyethylene/poly(vinyl acetate) blends were examined as a function of the polarizing temperature applied field and proportion of poly(vinyl acetate) in the blend. The peak TSDC current decreased and the its position shifted toward to a lower temperature as with increasing proportions of the poly(vinyl acetate) in the blends. The tendency of the current to flow in the same direction as the charging current also increased. Blending with poly(vinyl acetate) modifies increases the proportion of amorphous material in the polyethylene blends. The carriers with a mobility enhanced by hopping centres related to carbonyl groups in the amorphous portion were mainly localised in shallow traps. 32 refs. Rani Durgavati University INDIA


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Item 170 Polymer 47, No.10, 2006, p.3591 MICROSTRUCTURAL STUDIES ON BACL2 DOPED POLY(VINYL ALCOHOL) Bhajantri R F; Ravindrachary V; Harisha A; Crasta V; Nayak S P; Poojary B We have studied the effect of BaCl2 dopant on the optical and microstructural properties of a polymer poly(vinyl alcohol) (PVAl). Pure and BaCl2 doped PVA films were prepared using solvent casting method. These films were characterized using FTIR UV-visible XRD and DSC techniques. The observed peaks around 3425 cm-1 at 1733 cm-1 and 1640 cm-1 in the FTIR spectra were assigned to O-H C=C stretching and acetyle C=O group vibrations respectively. In the doped PVAl shift in these bands can be understood on the basis of intra/inter molecular hydrogen bonding with the adjacent OH group of PVA. The UVvisible spectra shows the absorption bands around 196 nm and shoulders around 208 nm with different absorption intensities for doped PVAl which are assigned to n->pi*transition. This indicates the presence of unsaturated bonds mainly in the tail-head of the polymer. Optical band energy gap is estimated using UV-visible spectra and it decreases with increasing dopant concentration. The powder XRD shows an increase in crystallinity in the doped PVAl which arises due to the interaction of dopant with PVAl causing a molecular rearrangement within the amorphous phase of polymer. These modifications also influence the optical property of the doped polymer. The DSC study also supports increasing crystalline thickness and degree of crystallinity due to doping. 17 refs. Mangalore University INDIA

Accession no. 972463 Item 171 International Journal of Plastics Technology 9, No.1-2, 2005, p.539 CROSSLINKED POLY(VINYL ALCOHOL)(PVA) MEMBRANES WITH PHOSPHOMOLYBDIC ACID(PMA) FOR DIRECT METHANOL FUEL CELLS Anis A; Banthia A K A composite membrane based on crosslinked PVAl and phosphomolybdic acid was prepared and its proton conductivity and methanol diffusivity were studied. The highest proton conductivity of 0.0101 S/cm was measured at room temperature. A diffusion cell was constructed and used to evaluate the methanol diffusivity of these composite electrolyte membranes in an aqueous methanol solution of 50% v/v. The methanol diffusion coefficients for these composite membranes ranged from 2.11 x 10-7 to 3.1 x 10-6 cm2/s. 13 refs.



Indian Institute of Technology INDIA

Accession no. 972168 Item 172 ACS Polymeric Materials: Science and Engineering, Fall Meeting 93, 2005, p.1037 CUTINASES CATALYZE THE DEACETYLATION OF POLYVINYL ACETATE Ronkvist A; Shah V; Kudasheva D; Gross R The use of two different cutinises as enzymatic catalysts in the deacetylation of polyvinyl acetate deposited on silica beads was evaluated using nuclear magnetic resonance spectroscopy to determine the percentage deacetylation. The effect of the pH of the aqueous medium on the cutinise activity was examined. Up to 60 percent deacetylation was achieved within 24 hours and enzyme catalysis was proven. 10 refs. USA

Accession no. 971621 Item 173 ACS Polymeric Materials: Science and Engineering, Fall Meeting 93, 2005, p.981 MULTILAYER FABRICATION USING HYDROPHOBIC INTERACTIONS Shaw J K; Hsu L; McCarthy T J Multilayer assembly of polyvinyl alcohol (PVOH) on a hydrophobic surface by chemical modification of a PVOH layer followed by hydrophobic interaction with unmodified PVOH was demonstrated. Reaction of the hydroxyl groups in the surface layer of PVOH with heptafluorobutyryl chloride resulted in making the polymer hydrophobic. Surfaces were characterised by X-ray photoelectron spectroscopy atomic force microscopy ellipsometry and contact angle measurements. Coatings up to several nanometers thickness could be obtained in a controlled manner using this technique. 14 refs. USA

Accession no. 971592 Item 174 ACS Polymeric Materials: Science and Engineering, Fall Meeting 93, 2005, p.771 TRIBOLOGY STUDY OF PVA CONTACT LENS IN IONIC AQUEOUS ENVIRONMENTS Jinping Dong; Haugstad G D The surface mechanical behaviour of daily disposable PVAl contact lenses in ionic aqueous environments was investigated by scanning probe microscopy. Friction force images at particular loads were acquired and analysed as histograms to obtain a spectroscopic lineshape of friction


comparable between saline types. Surface roughness adhesion and stiffness values extracted from volume spectroscopy measurements recorded under different conditions were also obtained and the surface behaviour of the lenses in different saline conditions compared. 6 refs. USA

Accession no. 970774 Item 175 Journal of Polymer Science: Polymer Physics Edition 44, No.13, 2006, p.1813 EFFECT OF POLY(VINYL ALCOHOL) FINE PARTICLES AS A NOVEL BIODEGRADABLE NUCLEATING AGENT ON THE CRYSTALLIZATION OF POLY(3HYDROXYBUTYRATE) Alata H; Hexig B; Inoue Y The effects of fine particles of poly(vinyl alcohol)(PVA) as biodegradable nucleating agent on the crystallisation of bacterial poly(3-hydroxybutyrate) (PHB) were investigated using DSC WAXD and polarised optical microscopy. The results are discussed in comparison with the crystallisation of blends of PVA with PHB and with the effects of conventional non-biodegradable nucleating agents such as talc. 30 refs. Tokyo Institute of Technology JAPAN

Accession no. 970627 Item 176 ACS Polymeric Materials: Science and Engineering, Fall Meeting 93, 2005, p.619 PHOTOLUMINESCENCE STUDIES OF TIN OXIDE NANOFIBERS PREPARED BY ELECTROSPINNING Hak-Yong Kim; Nallasamy D; Kwan-Woo Kim; Myung-Seob Khil; Chi-Hun Kim Calcination of a composite of polyvinyl acetate and tin oxide nanofibres prepared by electrospinning resulted in pure tin oxide nanofibres. These pure nanofibres were characterised by scanning electron microscopy tapping mode atomic force microscopy X-ray diffraction Raman spectroscopy and room temperature photoluminescence spectroscopy. Fibre diameter was seen to shrink during calcinations and photoluminescence emission decreased with increasing calcinations temperatures. These observations were discussed. 4 refs. INDIA; SOUTH KOREA

Accession no. 969631 Item 177 Polymer Testing 25, No.3, 2006, p.377

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ADDITION OF METHACRYLOYL GROUPS TO POLY(VINYL ALCOHOL) IN DMSO CATALYZED BY TEMED: OPTIMIZATION THROUGH RESPONSE SURFACE METHODOLOGY Crispim E G; Piai J F; Rubira A F; Muniz E C The addition of methacryloyl groups from glycidyl methacrylate (GMA) to poly(vinyl alcohol) PVA was investigated in the former paper of this series. In this report this reaction was optimized by response surface methodology (RSM). In the first step the main and the interaction effects of reaction time temperature and environment (either room atmosphere or N2 bubbling) on the degree of substitution (DS) were investigated through a 23 factorial design and by keeping the feed solution molar ratio (-OH(PVA)/GMA) equal to 1/0.05. DS was calculated from the respective 1H NMR spectrum. The results showed that the reaction time and temperature inputs are significant (P= less than 0.05) for the incorporation of methacryloyl groups into PVA chains. In the second step maximum DS was achieved by the use of RSM at 62 deg.C and reaction time of 6h. In these optimized conditions molar ratios (-OH(PVA)/GMA) equal to 1/0.10 1/0.25 1/0.50 1/0.75 and 1/1 were investigated and the respective yield ranged from 91 to 93% when DS was up to 25 mol%. It is difficult to obtain more than 50 mol% substitution of PVA hydroxyl by methacryloyl groups even in these optimized conditions due to increased steric hindrance by the large number of the methacryloyl groups inserted into PVA. The response surface was based on the model DS=-19.70+6.09x10-1T+1.93t-3.89x10-3T2-5.21x10-2t22.14x10-2T*t where T is the temperature ( deg.C) and t the reaction time (hours). This model explained 99.2 of the 99.6% explainable statistical data. 22 refs. Maringa Universidade Estadual BRAZIL

Accession no.

969434

Item 178 Polymer Degradation and Stability 91, No.5, 2006, p.1192 THERMAL AND PHOTOCHEMICAL STABILITY OF POLY(VINYL ALCOHOL)/MODIFIED LIGNIN BLENDS Fernandes D M; Winkler Hechenleitner A A; Job A E; Radovanocic E; Gomez Pineda E A A kraft lignin derivative (KLD) obtained by reaction with p-aminobenzoic acid/phthalic anhydride was blended with poly(vinyl alcohol) (PVA) by solution casting from DMSO. PVA and PVA/KLD films were exposed to ultraviolet radiation (24, 48 and 96 h) and analyzed by thermogravimetry (TG) differential scanning calorimetry (DSC) infrared spectroscopy (FTIR) hydrogen nuclear magnetic resonance (1H-NMR) spectroscopy and scanning electron microscopy (SEM). PVA films show a loss of thermal stability due to irradiation. PVA/KLD reveals greater thermal stability than PVA and an increase in thermal stability after irradiation. These results suggest

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that the incorporation of KLD into PVA provides a gain in thermal and photochemical stability. FTIR 1H NMR DSC and TG results obtained for the blends suggest that intermolecular interactions between PVA and KLD chains are present. SEM micrographs revealed blend miscibility for a KLD blend content of up to 15 wt% as observed at magnification of 1000 times. 20 refs. Copyright (c) 2006 Elsevier Ltd. Maringa Universidade Estadual; Paulista Universidade Estadual BRAZIL

Accession no. 969400 Item 179 Polymer Degradation and Stability 91, No.5, 2006, p.1147 FOAMED ARTICLES BASED ON POTATO STARCH CORN FIBERS AND POLY(VINYL ALCOHOL) Cinelli P; Chiellini E; Lawton J W; Imam S H Single-use packaging materials made of expanded polystyrene (EPS) have been identified as suitable items to be replaced by biodegradable materials. Plates made with EPS represent a source of non-degradable waste that is difficult to collect and to recycle. Potato starch based foamed plates have been prepared by a baking process. Presently foam plates have been prepared by baking aqueous mixtures of potato starch corn fibres and poly(vinyl alcohol) (PVA) inside a hot mould. The effects of the addition of corn fibres a co-product of bio-ethanol production on mechanical properties and moisture resistance of potato starch based foamed plates were investigated. The addition of corn fibre to potato starch batter increased baking time and an increased batter volume is needed to form a complete tray. The mechanical properties of the trays decreased with added corn fibre. In previous studies PVA has been added as aqueous solution to improve strength flexibility and water resistance of baked starch trays. In this study 88% hydrolyzed PVA was added as a powder in the mixture avoiding the time consuming and costly step of pre-dissolving the PVA. The addition of PVA to potato starch batters containing corn fibre mitigated the reduction in tensile properties seen in trays with added corn fibre. Starch-based trays produced with a high fibre ratio and PVA showed improved water resistance. 27 refs. Pisa University; US Dept. of Agriculture EUROPEAN COMMUNITY; EUROPEAN UNION; ITALY; USA; WESTERN EUROPE

Accession no. 969396 Item 180 Polymer Plastics Technology and Engineering 45, No.1-3, 2006, p.341 SYNTHESIS CHARACTERIZATION AND APPLICATION OF POLY(ACRYLAMIDE)/ POLY(VINYL ALCOHOL) POLYBLENDS



Ibrahim N A; Hebeish A; Fahmy H M; Abo-Shosha M H Free radical polymerisation of acrylamide(Aam) in the presence of aqueous solutions of three commercial grades of PVAl i.e. Vinarol FV (containing very few acetyl groups) Mowiol 4-80 (low viscosity-partially hydrolysed) and Vinarol STH (medium viscosity-partially hydrolysed) using ammonium persulphate(AP) initiator was shown to result in three corresponding PVAl/Aam polyblends. Optimum polymerisation conditions were PVAl and AP concentrations of 10% and 0.05 mol/L respectively Aam concentration 50% based on the weight of PVA polymerisation temperature 70C polymerisation time 20 min and rate of stirring 200 rpm. Under these conditions the three polyblends were prepared at very high degrees of polymerisation ranging from 98.2 to 99.9%. Rheological properties of 10% aqueous solutions of the polyblends at 80C were studied. The extent of film resolubility of PVAls and their polyblends was determined. Sizing of gauzy cotton fabric with the polyblends and PVAls was studied with reference to tensile properties and desizability. 47 refs. Egypt National Research Centre EGYPT

Accession no. 969122 Item 181 Polymer Plastics Technology and Engineering 45, No.1-3, 2006, p.213 EFFECT OF ACCELERATED AGING ON PROPERTIES OF KENAF (HIBISCUS CANNABINUS) PAPER SIZED WITH VARIOUS POLYMERS Ashori A; Harun J; Raverty W D; Yusoff M N M The effect of ageing on the properties of paper sized with chitosan cationic starch and PVA was investigated under accelerated conditions (90C and 50% RH). The results of this study demonstrated that the brightness and pH of papers decreased with an increase in ageing time. At each ageing time paper sized with chitosan showed the highest reduction in brightness whereas decreases in brightness in papers sized with PVA and cationic starch did not show much difference. The results demonstrated that paper sized with any of the polymers gave higher levels of tear index tensile index and folding endurance than the control sheet. Statistical analysis indicated that the polymers used in this experiment had a statistically-significant effect on the folding endurance of sized paper that was highest in the cases of PVA and chitosan. 12 refs. Iranian Research Organization of Science & Technology; Commonwealth Scientific & Industrial Research Organisation; Putra Malaysia Universiti; Forest Research Institute of Malaysia AUSTRALIA; IRAN; MALAYSIA



Item 182 Designed Monomers and Polymers 9, NO.3, 2006, P.303 SYNTHESIS OF ULTRA-HIGH-MOLECULARWEIGHT PVA USING TWO-STAGE PHOTOCONCENTRATED EMULSION POLYMERIZATION OF VINYL ACETATE Lin C-A; Wu C-R; Tsai H-C The synthesis of ultra-high molecular weight poly(vinyl alcohol) by a two-stage photo-concentrated emulsion polymerisation of vinyl acetate in the presence of poly(oxyethylene) nonyl phenyl ether sodium sulphate as emulsifier and in the absence of initiators followed by hydrolysis is described. The polymer was characterised by proton NMR and degree of polymerisation and the results are discussed in comparison with those for the products of emulsion polymerisation carried out in the presence of potassium persulphate as initiator. 17 refs. Taiwan Feng Chia University TAIWAN

Accession no. 968491 Item 183 Polymer Degradation and Stability 91, No.8, 2006, p.1740 THE NEGATIVE BIODEGRADATION OF POLY(VINYL ALCOHOL) MODIFIED BY ALDEHYDES Hui Zhen Zhang; Bai Ling Liu; Rong Luo; Yongzhong Wu; Desong Lei Due to the wide application of PVA acetals the biodegradation of PVA modified by formaldehyde n-butyraldehyde glyoxaldehyde and glutaraldehyde was conducted in an intensive biodegradation environment. Spectrophotometric analysis and weight loss were used to determine the biodegradation of PVA and the changes of the mechanical properties of PVA acetals were also studied. An obvious decrease in biodegradation levels of all the modified samples was found and a decrease in biodegradation level with increasing degree of acetals of PVA. The biodegradation of poly(vinyl formal) is better than poly(vinyl butyral) with the same degree of acetals whereas the biodegradation levels of poly(vinyl glyoxal) are lower than poly(vinyl glutaral) which has the same degree of crosslinking. The difference between the FT-IR of the samples before and after biodegradation indicated scission of residual PVA chain during the process. 30 refs. Chinese Academy of Sciences CHINA

Accession no. 968361 Item 184 Analytica Chimica Acta 566, No.1, 2006, p.271 NOVEL NANOSTRUCTURED MATERIALS TO

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DEVELOP OXYGEN-SENSITIVE FILMS FOR OPTICAL SENSORS Fernandez-Sanchez J F; Cannas R; Spichiger S; Steiger R; Spichiger-Keller U E

MORPHOLOGY AND MECHANICAL AND ELECTRICAL PROPERTIES OF ORIENTED PVA-VGCF AND PVA-MWNT COMPOSITES Bin Y; Mine M; Koganemaru A; Jiang X; Matsuo M

The development of optical oxygen-sensitive sensors by incorporation of organometallic compounds into a matrix of poly(vinyl acetate) containing nanostructured materials such as aluminium oxide silicon oxide or zirconium oxide was investigated. The photostability and the effects of sterilisation by autoclaving and gamma irradiation on the performance of the optodes are discussed in comparison with other types of oxygen sensors. Granada University; ETH Zurich

Composites of poly(vinyl alcohol) (PVA) with vapourgrown carbon fibres (VGCFs) and multi-wall carbon nanotubes (MWNTs) were prepared by gelation/ crystallisation from aqueous dimethyl sulphoxide. The composite films were uniaxially elongated to five- to ten-fold. The mechanical properties of PVA composites were improved significantly as a result of the introduction of VGCFs and MWNTs and by the orientation of the fillers. Because of their network structure MWNTs were more effective than VGCFs in improving the electrical conductivity of the composites. The change in the electrical conductivity of PVA/MWNT composites containing 5 wt% of MWNTs was independent of the draw ratio up to eight-fold indicating that there was no disruption of network formation. 26 refs.

EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; SWITZERLAND; WESTERN EUROPE

Accession no. 967740 Item 185 Polymer 47, No.4, 2006, p.1324 HIGHLY ISOTACTIC POLY(VINYL ALCOHOL) DERIVED FROM TERT-BUTYL VINYL ETHER. PART IV. SOME PHYSICAL PROPERTIES STRUCTURE AND HYDROGEN BONDING OF HIGHLY ISOTACTIC POLY(VINYL ALCOHOL) FILMS Ohgi H; Sato T; Hu S; Horii F Fundamental physical properties of films of various stereoregular poly(vinyl alcohol) samples including highly isotactic PVA (HI-PVA) derived from tert-butyl vinyl ether were examined. The melting temperature degree of crystallinity and carbon-13 spin-lattice relaxation time of the crystalline component showed and distinct minima at an mm fraction of about 0.4-0.5 suggesting that structural disordering associated with the decrease in crystallinity may be most strongly induced at this mm fraction. The formation of a new crystal form of PVA was reconfirmed for HI-PVA samples with mm fractions of more than about 0.55 and the structure and hydrogen bonding were investigated in detail by solid-state carbon-13 NMR. All OH groups can form successive intramolecular hydrogen bonds along their respective chains in the crystalline region for HI-PVA samples with mm fractions of more than about 0.7. These chains may adopt a slightly helical structure with a very long period. The appearance of minima in physical values may be related to the introduction of disordered units mainly as a result of hydrogen bonding to syndiotactic or isotactic sequences. 43 refs. Kuraray Co.Ltd.; Kyoto University JAPAN

Accession no. 967514 Item 186 Polymer 47, No.4, 2006, p.1308

Nara Women's University JAPAN

Accession no. 967512 Item 187 Polymer 47, No.4, 2006, p.1073 SYNTHESIS OF POLY(VINYL ALCOHOL) COMBS VIA MADIX/RAFT POLYMERIZATION Bernard J; Favier A; Davis T P; Barner-Kowollik C; Stenzel M H Poly(vinyl acetate) (PVAc) combs were prepared by xanthate (MADIX)/reversible addition-fragmentation chain-transfer (RAFT) polymerisation using xanthatefunctionalised polymer cores. The comb backbones were prepared by using well-defined poly(vinyl alcohol) samples with degrees of polymerisation of 20 100 and 170. Functionalisation with xanthates through the R-group or Z-group approaches resulted in the formation of macromolecular MADIX agents. Whereas Z-group-containing macromolecular xanthate agents appeared to inhibit the polymerisation of vinyl acetate R-group-containing agents effectively mediated the bulk polymerisation of VAc to give PVAc combs. However the growth of the combs was accompanied at low conversions by the formation of linear polymer chains and shoulders as a result of the constant initiation and intermolecular coupling reactions respectively. The proportions of single chains and termination products increased with increasing degree of polymerisation of the macromolecular MADIX agents. The stable ester link between the branches and the PVA backbone permitted the branched PVAc architectures to be hydrolyzed to give poly(vinyl alcohol) combs. 35 refs. New South Wales University AUSTRALIA


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Item 188 Macromolecules 39, No.8, 2006, p.2921 SAXS STUDIES ON STRUCTURAL CHANGES IN A POLY(VINYL ALCOHOL) FILM DURING UNIAXIAL STRETCHING IN WATER Miyazaki T; Hoshiko A; Akasaka M; Shintani T; Sakurai S Structural changes in a poly(vinyl alcohol) (PVA) film during uniaxial stretching in water were examined by simultaneous tensile stress-strain measurements and small-angle X-ray scattering (SAXS) studies. At strains of less than 70% the crystalline lamellae orient in the direction perpendicular to the stretching direction and the intervening amorphous regions are elastically expanded with film drawing in proportion to the macroscopic deformation. At strains of more than 70% the molecular chains in the intermediate amorphous region are relaxed with lamellar break-up. Above 180% strain a structural transition of the lamellar structure to a microfibrillar structure occurs as suggested by the appearance of a transversal streak with an intensity maximum on each streak and a mechanical transition. In the final stage of deformation there is networking with a long-range connectivity composed of the microfibrils and the interfibrillar extended amorphous chains. The network of the interfibrillar extended amorphous region is considered to lead to strain-induced hardening which occurs at strains from 180% up to the break. 45 refs. Nitto Denko Corp.; KyotoInstitute of Technology JAPAN

Accession no. 966401 Item 189 Journal of Applied Polymer Science 100, No.3, 2006, p.2409 PREPARATION OF POLYSTYRENE/ POLY(VINYL ACETATE) NANOCOMPOSITES WITH A CORE-SHELL STRUCTURE VIA EMULSIFIER-FREE EMULSION POLYMERIZATION Soltan-Dehghan M; Sharifi-Sanlani N; Naderi N Nanoparticles with a core-shell morphology were prepared by using a two-stage emulsifier-free emulsion polymerisation of styrene and vinyl acetate using azo bisaminopropane dihydrochloride as both initiator and emulsifier. The resulting latex particles were characterised using scanning electron microscopy transmission electron microscopy and differential scanning calorimetry. Effects of different volume ratios of monomers reaction time and monomer addition method to the reaction medium were evaluated. 18 refs. Tehran University IRAN



Item 190 Journal of Polymer Science: Polymer Chemistry Edition 44, No.9, 2006, p.3083 COPOLYMERIZATION OF POLY(VINYL ALCOHOL)-GRAFT-POLY(14-DIOXAN-2ONE) WITH DESIGNATED MOLECULAR STRUCTURE BY A SOLID-STATE POLYMERIZATION METHOD Si-Chong Chen; Xiu-Li Wang; Ke-Ke Yang; Gang Wu; Yu-Zhong Wang The solid state copolymerisation of poly(vinyl alcohol)g-poly(14-dioxan-2-one) with designed molecular structure is described. The solid state copolymerisation is preceded by a higher temperature graft copolymerisation of poly(14-dioxan-2-one) with PVA as a multifunctional initiator. Polymers are characterised by NMR spectroscopy and DSC and compared with those synthesised in the homogeneous molten state. 34 refs. Sichuan University CHINA

Accession no. 965341 Item 191 Materials Science and Engineering 21, No.6, 2005, p.77 SYNTHESIS AND CHARACTERIZATION OF PVA SIDE-CHAIN LIQUID CRYSTALLINE Jiu-Fen Wang; Hong-Yan Xu; Li Chang The synthesis of a side-chain liquid crystalline PVAl using PVAl as electron donor and 4-stibazole as electron acceptor through molecular recognition is described. The thermotropic liquid crystalline behaviour phase transition temperature and flexibility of the liquid crystalline PVAl are discussed and the relationship between the liquid crystalline group and polymer backbone examined. 9 refs. North China Institute of Technology Polymer CHINA

Accession no. 964609 Item 192 Macromolecules 39, No.5, 2006, p.1709 POLY(VINYL ALCOHOL)-BASED HYDROGELS FORMED BY CLICK CHEMISTRY Ossipov D A; Hilborn J Poly(vinyl alcohol) (PVA) was functionalised with pendant acetylene and azide groups by carbonyldiimidazolemediated coupling with amines terminated with functional groups (1-azido-2-aminoethane propargylamine and N-methylpropargylamine). Azide-modified PVA and alkyne-modified PVA crosslinked when mixed in solution with Cu(I) catalyst. Chemoselective coupling between the functional groups resulted in multiple crosslinking and hydrogel formation. PVA-based hydrogels were

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also prepared by crosslinking alkyne-modified PVA with telechelic bifunctional poly(ethylene glycol)diazide crosslinker. The hydrogels were characterised by measurements of swelling in water viscoelastic properties in the swollen state and of the soluble fraction. The network properties were crosslinking-dependent. The use of polyfunctional PVA crosslinkers gave higher gelation capacity than the bifunctional PEG crosslinker. 50 refs. Uppsala University EUROPEAN UNION; SCANDINAVIA; SWEDEN; WESTERN EUROPE


in solutions of different concentrations and using glutaraldehyde as crosslinking agent was studied by measurement of intrinsic viscosity of PVAlc solutions determination of gel fraction and by gel swelling measurements. Effects of intramolecular cyclisation were calculated according to the molecular tree model. Gel growth was controlled by polymer concentration with no bulk gels formed below a particular concentration. Equilibrium swelling ratio reduces as polymer concentration increases. 25 refs. Jilin University; Petro China Co.Ltd. CHINA

Accession no. 961989 Item 193 CSIC Revista de Plasticos Modernos 91, No.596, 2006, p.153 PVA CRYOGELS; MECHANISMS FOR FORMATION STRUCTURE AND APPLICATIONS Hernandez R; Lopez D; Mijangos C A review is presented on the structure and applications particularly biomedical applications of PVAl cryogels and the preparation and characterisation of PVAl/gammacyclodextrin inclusion compounds and their influence on PVAl gelation by freeze-thawing. 50 refs. EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE Accession no. 963997 Item 194 Journal of Applied Polymer Science 99, No.5, 2006, p.2233 MECHANISM OF AIR/OXYGEN/HELIUM ATMOSPHERIC PLASMA ACTION ON PVA Cai Z; Qiu Y The effect of the air/oxygen/helium atmospheric plasma treatment on desizing PVAL on cotton fabric is discussed and compared with the conventional peroxide desizing. Possible changes of PVAL during atmospheric plasma exposure was induced through a combination of weight loss of PVAL after plasma PVAL dissolving rate in water at room temperature X-ray photoelectron spectroscopy and FTIR. 15 refs. Donghua University CHINA

Accession no. 963889 Item 195 Macromolecules 39, No.3, 2006, p.1160 INFLUENCES OF INTRAMOLECULAR CYCLIZATION ON STRUCTURE AND CROSSLINKING REACTION PROCESSES OF PVA HYDROGELS Dacheng Zhao; Guangzhi Liao; Ge Gao; Fengqi Liu Preparation of polyvinyl alcohol (PVAlc) hydrogels

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Item 196 China Chemical Reporter 17, No.4-5, 2006, p.17 NEW HYDROPHILIC PRESSURE-SENSITIVE ADHESIVE It is briefly reported that Tianjin University Chemical Industry School has developed a new gel-type pressuresensitive adhesive used in skin drug application systems. The hydrophilic PSA has good adhesion and low sensitisation and irritation. It has good compatibility with extracts and micro powders of traditional Chinese medicines. The PSA gels developed include PVP/PEG/ gelatin PVP/polyester/glycerin and PVP/PVA/glycerin varieties. Tianjin University CHINA

Accession no. 960276 Item 197 Polymers and Polymer Composites 14, No.1, 2006, p.39 RELEASE BEHAVIOUR OF BOVINE SERUM ALBUMIN IN SYNDIOTACTIC POLY(VINYL ALCOHOL) HYDROGEL PREPARED BY FREEZING-THAWING Won Seok Lyoo; Dong Soo Shin; Sung Soo Han; Seok Kyun Noh; Jung Ae Kim; Han Gon Choi; Chul Soon Yong; Jae-Ryong Kim; Jung Hye Kim The release behaviour of bovine serum albumin (BSA) in syndiotactic polyvinyl alcohol (PVA) hydrogels was studied with respect to the effect of some molecular parameters. The hydrogels were prepared by freezingthawing. Various syndiotactic PVAs were prepared by copolymerisation of vinyl pivalate and vinyl acetate and subsequent saponification. The effect on the release rate of factors such as stereoregularity degree of saponification and molecular weight of the syndiotacticity-rich PVA hydrogels was studied. Both the release rate and the amount of residual BSA was investigated with varying degrees of syndiotacticity. It was found that s-PVA hydrogels having various kinds of release behaviours could be prepared by control of the molecular and processing



parameters of PVA and these could be successfully used in various biomedical applications. 23 refs. Yeungnam University KOREA

Accession no. 958892 Item 198 Macromolecules 38, No.23, 2005, p.9488 SYNTHESIS OF POLY(VINYL ACETATE) AND POLY(VINYL ALCOHOL) CONTAINING BLOCK COPOLYMERS BY COMBINATION OF COBALT-MEDIATED RADICAL POLYMERIZATION AND ATRP Debuigne A; Caille J; Willet N; Jerome R Poly(vinyl acetate) (PVAc) chains of a low polydispersity (Mw/Mn = 1.1-1.2) were prepared by cobalt-mediated radical polymerisation of vinyl acetate (VAc). The polymers were end-capped by an activated bromide by the addition of an alpha-bromo ester or an alpha-bromo ketone containing a nitroxide to form effective macroinitiators for the atom-transfer radical polymerisation of styrene (S) ethyl acrylate or methyl methacrylate. Because each block is formed by a controlled process well-defined PVAc-containing diblock copolymers can be readily prepared. The PVAc-b-PS copolymers synthesised from alpha-bromo ketone end-capped PVAc can be converted into well-defined poly(vinyl alcohol)-b-polystyrene amphiphiles by methanolysis of the poly(vinyl acetate) block. Self-association of an amphiphilic poly(vinyl alcohol)-b-polystyrene in a water/tetrahydrofuran mixture results in the formation of vesicles. 22 refs. Solvay Research & Technology; Liege University BELGIUM; EU; EUROPEAN COMMUNITY; EUROPEAN UNION; WESTERN EUROPE; WESTERN EUROPE-GENERAL

Accession no. 957899 Item 199 Polymers and Polymer Composites 13, No.8, 2005, p.839 PREPARATION AND CHARACTERIZATION OF NI+-MONTMORILLONITE/POLYVINYL ALCOHOL WATER-SOLUBLE NANOCOMPOSITE FILM Li-Ping Wang; Yun-Pu Wang; Fa-Ai Zhang This paper describes the preparation of a new type of water-soluble nanocomposite film from polyvinyl alcohol Ni+2montmorillonite (Ni+2MMT) a defoaming agent a levelling agent and a plasticiser. Its thermal characteristics were studied by DSC and the intermolecular interactions were measured by FTIR and XPS. The tensile strength and elongation at break were also measured. The microstructures were studied by XRD and AFM. FTIR and XPS spectra indicated that crosslinking had taken place between PVA and Ni+2MMT. XRD and AFM indicated that the PVA molecules


had inserted themselves into the silicate layers of MMT exfoliating them and dispersing them randomly into the PVA matrix. Compared to pure PVA film the tensile strength of the films increased and the elongation at break decreased when the Ni+2MMT was added and the dissolution temperature of the film was also reduced. 23 refs. Lanzhou Northwest Normal University; Guilin University of Technology CHINA

Accession no. 956570 Item 200 China Synthetic Fiber Industry 28, No.5, 2005, p.1/7 STUDY ON SUPERABSORBENT BLEND FIBER OF COPOLY(ACRYLIC ACID-ACRYLAMIDE) AND PVA Ding Yuanrong; Xiao Changfa; An Shulin; Jia Guangxia 2-Hydroxypropyl acrylate a potential crosslinking agent was incorporated into an acrylic acid-acrylamide copolymer which was blended with PVAl and spun into fibres. The water absorption behaviour of the fibres following post-curing was investigated and the effects of post-curing on the structure and properties of the fibres investigated. 6 refs. Tianjin Polytechnic University CHINA

Accession no. 955290 Item 201 Journal of Applied Polymer Science 98, No.5, 2005, p.2290 BIOCOMPATIBLE POLYMER BLENDS: EFFECTS OF PHYSICAL PROCESSING ON THE MOLECULAR INTERACTION OF POLY(VINYL ALCOHOL) AND POLY(VINYL PYRROLIDONE) Jones S A; Martin G P; Royall P G; Brown M B The rapid removal of a solvent by spray drying of partially hydrolysed poly(vinyl alcohol) (PVA)/poly(vinyl pyrrolidone) (PVP) altered the solid-state properties of the material compared with the case of casting the blend to form a film. Although thermal analysis showed that PVP functions as a plasticiser (reducing the melting point of PVA) spray drying the product rather than using a film-casting procedure improved its solid-state stability and resulted in the formation of a second crystalline phase within the material. Variations in the solid-state properties of manufactured PVA/PVP blends arose from structural differences in the composite produced by differences in the processing method used to form the blend. The solid-state properties of blended products can be altered by careful manipulation of the manufacturing process. 35 refs. London University King's College EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE


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Item 202 China Chemical Reporter 16, No.32, 2005, p.23 POLYMER EMULSION ADHESIVES ENTER SOUND DEVELOPMENT STAGE Beifan G The annual output growth of polymer emulsion adhesives in China was 20% from 2001 to 2004 the highest level in the world. Output in China was 1.483 million tons in 2004 an increase of 16.6% over 2003. It is expected that the annual output growth will be 12-15% reaching 3.0 million tons in 2010. Polymer emulsion adhesives include polyacrylate emulsion polyvinyl acetate emulsion vinyl acetate-ethylene copolymer emulsion and PU emulsion. Output of these major polymer emulsion adhesives in China is outlined. CHINA

Accession no. 954715 Item 203 Polymer 46, No.21, 2005, p.9170 MISCIBILITY AND INTERACTIONS IN POLY(NPROPYL METHACRYLATE)/POLY(VINYL ALCOHOL) BLENDS Yi J Z; Goh S H Blends of poly(propyl methacrylate) (PPMA) and poly(vinyl alcohol) (PVA) were prepared over the whole composition range by mixing DMF solutions of each polymer and evaporating the mixture to dryness. The blends were characterised by DSC FTIR and high-resolution solid-state carbon-13C-NMR using CP/MAS experiments. All blends were transparent and showed a single glass transition temperature indicating complete miscibility. The spectral changes upon blending indicated that the PVA hydroxyl groups were interacting with the PPMA carbonyl groups. The blends were homogeneous on a scale of 20-30 nm but not 1-3 nm. The results were discussed in relation to published work for PVA and poly(p-vinylphenol) blends with poly(methylthiomethyl methacrylate) and the influence of the sulphur atom. 29 refs. Sun Yat-Sen University; Singapore National University CHINA; SINGAPORE

Accession no. 954174 Item 204 Journal of Applied Polymer Science 98, No.6, 2005, p.2339 DEVELOPMENT OF POTENTIALLY BIODEGRADABLE POLYAMIDE-6 AND POLYVINYL ALCOHOL BLENDS: PHYSICOMECHANICAL PROPERTIES THERMAL PROPERTIES AND SOIL TEST Ramaraj B; Poomalai P

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Different blends of polyamide-6 with polyvinyl alcohol (PVA) are prepared in a twin-screw extruder and the extrudate injection moulded to make test specimens. The biodegradation properties are evaluated. In soil tests all blends show enhanced biodegradability water absorption and density. However introduction of PVA into the polyamide-6 matrix gives considerable reduction in tensile strength heat distortion temperature vicat softening point and hardness initially but this reduction is absent on subsequent addition because of the enhanced interaction between amide and hydroxyl groups. 34 refs. Central Institute of Plastics Engineering & Technology INDIA

Accession no. 953666 Item 205 International Polymer Science and Technology 32, No.6, 2005, p.T/42-4 CALORIMETRIC STUDY OF BLENDS BASED ON POLYVINYL ALCOHOL AND POLYHYDROXYBUTYRATE Ol'khov A A; Iordanskii A L; Fel'dshtein M M A calorimetric study is described of blends based on polyhydroxybutyrate (PHB) and polyvinyl alcohol (PVA). The polymers were mixed in PVA/PHB ratios (wt%) of 90:10 80:20 70:30 and 50:50. Films were produced from the blends by extrusion of the melt through a plane slit head using a single-screw extruder. Calorimetric studies of the films were carried out using a differential scanning calorimeter. It was seen that films based on PVA were characterised by the presence of two types of crystal structure and one glass transition. In composites based on PVA and PHB the same picture is observed but the melting peak of the crystalline phase of PHB is superimposed on the high-temperature peak of melting of the PVA. It was concluded that the components of the blends were partially compatible indicated by an increase in the Tg and a reduction in the specific heat of the PVA phase. Other conclusions reached were that the degree of crystallinity of the PVA falls considerably with an increase in the PHB content of the blend and that the parameters of the crystallites in the mixed polymers hardly change as a function of the composition of the composites. 10 refs. (Article translated from Plasticheskie Massy No.10 2004 p.25-6) Lomonosov M.V.Academy of Fine Chemical Technology; Russian Academy of Sciences RUSSIA

Accession no. 953438 Item 206 Proceedings of the 63rd SPE Annual conference (ANTEC 2005) held Boston, MA pp.5 EFFECT OF NANOCLAY ON EFFICIENCY OF LOW PROFILE ADDITIVES (LPAS) ON



SHRINKAGE CONTROL OF UNSATURATED POLYESTER (UP) RESIN Xia Cao; Lee L J

and mechanical properties of the non-woven mats are discussed. 23 refs.

The addition of a small quantity of nanoclay (3 wt %) can greatly enhance the efficiency of low profile additives (LPAs) for volume shrinkage control of low profile unsaturated polyester(UP)/styrene/LPA systems. In this study the effect of nanoclay on volume shrinkage of low profile UP resins containing PS PMMA and PVAc respectively was investigated by an integrated approach of static phase characteristics of uncured resin mixture morphology of the cured samples reaction kinetics and shrinkage measurement. The results revealed that nanoclay greatly increased the fraction of LPA-rich phase leading to more micro-cracking in the LPA-rich phase or at the interface of the LPA-rich and UP-rich phases and therefore to a marked improvement of volume shrinkage control. The effects of structure/properties of LPAs and surface property of nanoclay on shrinkage of UP resin were also investigated. 14 refs

KOREA

USA

Accession no. 953369 Item 207 EP 1593726 A1 20051109 WATER-BASED VULCANIZABLE ADHESIVE COMPOSITION Fukasawa K; Abe K Disclosed is an aqueous vulcanisable adhesive composition which comprises a phenol resin emulsion prepared from a water-insoluble phenol resin solution in methyl ethyl ketone and an aqueous water-soluble polymeric substance solution and a curing agent for the phenol resin. It uses a partially water-miscible methyl ethyl ketone in place of a completely water-miscible organic solvent. PVA preferably aceto-acetyl-modified PVA is used as the watersoluble polymeric substance. The adhesive composition is suitably used for vulcanisation bonding of a metal to (hydrogenated) NBR or acrylic rubber. Accession no. 953008 Item 208 Macromolecular Research 13, No.5, 2005, p.385 CHARACTERIZATION OF PVOH NONWOVEN MATS PREPARED FROM SURFACTANTPOLYMER SYSTEM VIA ELECTROSPINNING Jung Y H; Kim H Y; Lee D R; Park S Y; Khil M Y The fabrication of poly(vinyl alcohol) non-woven mats by electrospinning polymer solutions containing various concentrations of cationic anionic amphoteric and nonionic surfactants characterised by surface tension viscosity and conductivity was investigated by SEM tensile strength and elongation at break measurements. The effects of polymer-surfactant interactions on the morphological


Chonbuk National University Accession no. 952902 Item 209 Journal of Macromolecular Science B B44, No.5, 2005, p.779 PREPARATION AND PHYSICAL PROPERTIES OF CARBON NANOTUBES-PVA NANOCOMPOSITES Ciambelli P; Sarno M; Gorrasi G; Sannino D; Tortora M; Vittoria V The preparation of nanocomposites of poly(vinyl alcohol) (PVA) with various proportions of oxidised multiwall carbon nanotubes (MWNTs) under different processing conditions and their characterisation by FESEM TEM DSC TGA FTIR Raman spectroscopy and DMTA is described. The results were compared with those for PVA itself and the effects of MWNTs on structural mechanical and thermal properties are discussed. 53 refs. Salerno University EU; EUROPEAN COMMUNITY; EUROPEAN UNION; ITALY; WESTERN EUROPE; WESTERN EUROPE-GENERAL

Accession no. 952824 Item 210 E-Polymers 24, No.72, 2005, p.1 DRUG-LOADED ULTRAFINE POLY(VINYL ALCOHOL) FIBRE MATS PREPARED BY ELECTROSPINNING Chunxue Zhang; Xiaoyan Yuan; Lili Wu; Jing Sheng The preparation of submicron polyvinyl alcohol (PVA) fibre mats embedded with Aspirin and bovine serum albumin from electrospun aqueous solutions is described. SEM is used to investigate the fibre morphology and the fibre mat composition is characterised by FTIR spectroscopy and X-ray photoelectron spectroscopy. The in vitro drug release is investigated by immersing the fibre mats in phosphate buffer solution. The fibre mat morphology is influenced by the amount of drug in the mats with more irregular shaped fibres found for higher drug content. The drugs are released more quickly from PVA mats than from PVA cast films because of the large surface area and high porosity of the fibres. 15 refs. Tianjin University CHINA

Accession no. 952706 Item 211 Journal of Polymers and the Environment 13, No.3, 2005, p.267

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POLY(VINYL ALCOHOL)/COMPOST COMPOSITES FOR BIOFILTRATION OF SWINE WASTE VOLATILES Wu-Chung Chan; Rui-Xiang Zheng

Taiwan National Chung-Hsing University

The preparation of a poly(vinyl alcohol) (PVA)/compost composite bead for biofiltration is reported. The composite bead is prepared by blending PVA with swine manure compost and fixing with boric acid and phosphate. The moisture absorption/holding capacity compressive strength nutrient content and density of the bead are characterised. The ethyl acetate removal efficiency pH and head loss of the composite bead and swine manure compost beds are also reported during biofilter operation. 18 refs.

Item 214 Journal of Polymer Science: Polymer Physics Edition 43, No.17, 2005, p.2399 POLYMER-FILLER INTERACTIONS IN SOLGEL DERIVED POLYMER/SILICA HYBRID NANOCOMPOSITES Bandyopadhyay A; De Sarkar M; Bhowmick A K

Chung-Hua University TAIWAN

Accession no. 951579 Item 212 Journal of Polymers and the Environment 13, No.3, 2005, p.253 MOISTURE SORPTION CHARACTERISTICS OF MICROBIALLY PRODUCED POLYSACCHARIDE AND POLYVINYL ALCOHOL BLENDS Sudhamani S R; Raj A E; Raj B; Prasad M S The moisture sorption characteristics of microbial polysaccharide from Pseudomonas caryophilli and polyvinyl alcohol (PVA) blends are reported for water activity from 0.1 to 0.9 at 27C. The sorption data is used to fit six different sorption isotherm models. The ranges of applicability of water activity for isotherm models lie between 0.1 and 0.4 for a BET model and between 0.2 and 0.9 for other models. 28 refs. India Central Food Technological Research Inst. INDIA

Accession no. 951577 Item 213 Journal of Cellular Plastics 41, No.5, 2005, p.437 EFFECTS OF DIE SHAPES AND ADDITIVES ON THE PHYSICAL AND MECHANICAL PROPERTIES AND CELLULAR STRUCTURE OF BIODEGRADABLE CUSHIONING EXTRUDED FOAMS Lui W-B; Peng J The effects of die shape poly(vinyl alcohol)(PVA) ratio and additives (sodium bicarbonate calcium carbonate calcium hydroxide) on the physical mechanical and morphological properties of corn-PVA composite extruded foams were investigated by longitudinal expansion bulk density compressibility spring index and SEM. The experimental data was subjected to statistical analysis and the results are discussed. 37 refs.

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TAIWAN


The effect of polymer-filler interactions on swelling and dynamic mechanical properties of the sol-gel derived acrylic rubber (ACM)/silica epoxidised natural rubber (ENR)/silica and poly(vinyl alcohol) (PVA)/ silica hybrid nanocomposites is described. The Kraus constants determined from the swelling measurements are substantially higher than that of carbon black filled conventional rubber composites. To understand the polymer-filler interaction the dynamic mechanical properties of the hybrid nanocomposites are studied at two temperatures. The drop in storage modulus with dynamic strain is found to be greatest for ACM/silica. For all systems the effect is higher at the higher temperature. The observations are due to the strength of polymer-filler interactions and the additional effects of higher thermal energy at the higher temperature. 34 refs. Kharagpur Indian Institute of Technology INDIA

Accession no. 950590 Item 215 Polymer Materials Science and Engineering 21, No.3, 2005, p.212 PREPARATION AND EVALUATION OF PVA POLARIZING FILM Ya-Man Zuo; Wan-Qi Qiu; Zheng-Yi Liu; Jian-Xun Gong Polarising films containing iodine and iodine nickel and cobalt were fabricated and their optical properties investigated. 5 refs. South China University of Technology CHINA

Accession no. 948126 Item 216 Journal of Polymer Science: Polymer Physics Edition 43, No.15, 2005, p.1944 STUDY OF THE EFFECT OF POLY(VINYL ALCOHOL) CONCENTRATION ON THE GELATION POINT OF POLY(VINYL ALCOHOL) POLY(ACRYLIC ACID) SEMI-IPN SYSTEMS AS DETERMINED BY VISCOELASTIC MEASUREMENTS Henandez R; Mijangos C; Lopez D



The effects of poly(vinyl alcohol)(PVA) concentration on the gelation point of PVA/poly(acrylic acid) semiinterpenetrating network (semi-IPNs) systems prepared by a sequential method and crosslinked with N,N'methylenebisacrylamide were investigated by viscoelastic measurements. The molecular structures of the semiIPNs are discussed in terms of loosely crosslinked gels composed of swollen clusters. 22 refs. Madrid Instituto de Ciencia y Tec.de Polim EU; EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE; WESTERN EUROPE-GENERAL

Accession no. 947761 Item 217 Macromolecular Research 13, No.4, 2005, p.314 PREPARATION OF ION EXCHANGE MEMBRANES FOR FUEL CELL BASED ON CROSSLINKED POLY(VINYL ALCOHOL) WITH POLY(ACRYLIC ACID-CO-MALEIC ACID) Dae Sik Kim; Ho Bum Park; Chang Hyun Lee; Young Moo Lee; Go Young Moon; Sang Yong Nam; Ho Sang Hwang; Tae II Yun; Ji Won Rhim Crosslinked polyvinyl alcohol (PVA) membranes are prepared at various crosslinking temperatures using poly(acrylic acid-co-maleic acid) (PAM) with differing PAM content. The proton conductivity and methanol permeability are investigated for PVA/PAM membranes with 3-13 wt% in the temperature range 25-80C. Both properties are very dependent of the PAM content and decrease with increasing PAM content. Ambient temperature proton conductivity is in the range 0.0010.001 S/cm and the methanol permeability in the range 10-7 to 10-6 cm2/s. The effects of crosslinking and concentration of ionomer groups are discussed in terms of water content ion exchange capacity and fixed ion concentration. 18 refs. Hanyang University; LG Chem; Gyeongsang National University; Hannam University KOREA

Accession no. 947678 Item 218 Journal of Membrane Science 259, No.1-2, 2005, p.65 SIGNIFICANT INCREASE OF PERMEATION FLUX AND SELECTIVITY OF POLY(VINYL ALCOHOL) MEMBRANES BY INCORPORATION OF CRYSTALLINE FLAKE GRAPHITE Peng F; Lu L; Hu C; Wu H; Jiang Z The preparation of poly(vinyl alcohol)(PVA) membranes incorporating crystalline flake graphite and their characterisation by positron lifetime spectroscopy and degree of swelling is described. The effects of graphite content feed composition and operating temperature on


the pervaporation properties of the composite membranes for separating benzene/cyclohexane mixtures were investigated and the results are discussed in comparison with those for PVA and crosslinked PVA membranes. Tianjin University CHINA

Accession no. 945711 Item 219 Macromolecules 38, No.13, 2005, p.5475 POLY(VINYL ESTER) STAR POLYMERS VIA XANTHATE-MEDIATED LIVING RADICAL POLYMERIZATION: FROM POLY(VINYL ALCOHOL) TO GLYCOPOLYMER STARS Bernard J; Favier A; Ling Zhang; Nilasaroya A; Davis T P; Barner-Kowollik C; Stenzel M H Xanthate interchange reversible addition fragmentation polymerisation with Xanthate attachment to the core by either a fragmenting or non-fragmenting covalent bond was used to prepare polyvinyl ester stars polymers. Using the fragmenting covalent bond approach resulted in welldefined star polymers of vinyl acetate vinyl pivalate or vinyl neodecanoate with narrow polydispersity. Polymers of wider polydispersity were obtained at medium to high conversions with the non-fragmenting covalent bond method probably due to congestion around the xanthate functionality. Conversion by hydrolysis of the polyvinyl esters to polyvinyl alcohol resulted in destruction of the star architecture due to cleavage of the xanthate linkage. Early experiments in the preparation of star shaped glycopolymers using the fragmenting covalent bond approach is described and discussed but further work in this area is still required 34 refs. New South Wales University AUSTRALIA

Accession no. 944734 Item 220 Journal of Membrane Science 255, No.1-2, 2005, p.181 SEPARATION OF AZEOTROPIC MIXTURE USING MODIFIED PVA MEMBRANE Upadhyay D J; Bhat N V PVAl membrane (4 wt %) was modified with 0.05 to 0.2 wt % lithium chloride in order to investigate the effect of addition of alkali salt on separation of water-isopropyl alcohol mixture. The surface of cast membranes was crosslinked by exposure to low-pressure nitrogen plasma. The separation performance of modified membrane was analysed by pervaporation technique at 25C and improvements in the flux and the selectivity for purification of water molecules were demonstrated. Characterisation of modified membranes was performed using FTIR spectroscopy DSC and wide-angle X-ray diffraction techniques. It was found that the membrane

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became semicrystalline to amorphous on addition of lithium chloride to PVAl which affected the separation performance. Randox Laboratories Ltd.; Bombay Textile Research Assn. EU; EUROPEAN COMMUNITY; EUROPEAN UNION; INDIA; UK; WESTERN EUROPE; WESTERN EUROPE-GENERAL

Accession no. 943160 Item 221 Journal of Membrane Science 250, No.1-2, 2005, p.167 IMMOBILIZATION OF CELLULASE IN NANOFIBROUS PVA MEMBRANES BY ELECTROSPINNING Lili Wu; Xiaoyan Yuan; Jing Sheng The immobilisation of the enzyme cellulase in nanofibrous poly(vinyl alcohol) (PVA) membranes was investigated by electrospinning from an acetic acid solution of PVA and cellulase and crosslinking by glutaraldehyde vapour. The catalytic activity of the immobilised enzyme was compared to that of the free enzyme and the effects of enzyme loading efficiency and crosslinking time on catalytic activity are discussed. Tianjin University CHINA

Accession no. 941320 Item 222 Polymer International 54, No.5, 2005, p.796 PREPARATION AND CHARACTERIZATION OF SPONGY CRYOGELS OF POLY(VINYL ALCOHOL)-CASEIN SYSTEM: WATER SORPTION AND BLOOD COMPATIBILITY STUDY Bajpai A; Saini R Novel blend hydrogels of polyvinyl alcohol (PVA) and casein were prepared by repeated freeze-thaw cycles of aqueous solutions. The dried gel pieces were characterised by FTIR spectroscopy DSC and SEM. The water sorption capacities of the gels were determined and the effects of the PVA and casein components the number of freeze-thaw cycles pH temperature salts and swelling bath temperature were estimated. The hydrogels showed a good degree of blood capacity during tests for bovine serum albumin adsorption blood clot formation and haemolytic activity. 40 refs. Jabalpur Government Autonomous Science College INDIA

Accession no. 940919 Item 223 Journal of Applied Polymer Science 96, No.3, 2005, p.808

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PROPERTIES OF CHITOSAN/POLY(VINYL ALCOHOL) FILMS FOR DRUG-CONTROLLED RELEASE Qun Wang; Yu-min Du; Li-hong Fan Combination crosslinked polymer films of chitosan and polyvinyl alcohol (PVA) crosslinked and loaded with bovine serum albumin as a model drug were prepared by casting and solvent evaporation. They were characterised using X-ray diffraction scanning electron microscopy Fourier transform infrared spectroscopy and their drug release properties were determined. Drug release was affected by component ratio of the films loading of model drug and pH and ionic strength of the release solution. Highest drug release rates were obtained at low drug levels high PVA levels in the film low pH levels in the release solution and high ionic strength of the release solution. Crosslinking of the films reduced release rates. 24 refs. Wuhan University CHINA

Accession no. 940699 Item 224 Molecular Crystals and Liquid Crystals 426, 2005, p.205 NEW OPTICAL NONLINEAR MATERIAL BASED UPON PVA WITH PBS QUANTUM DOTS Lyakhovetsky V R; Volkov V I; Borshch A A; Brodyn M S; Strashnikova M I; Reznichenko V Y; Kutsenko A S; Maloletov S M; Kuchmy S Y; Kajzar F The preparation of nanocomposite films of poly(vinyl alcohol) with nanocrystals of the semiconductor lead sulphide and their characterisation by XRD microinterferometry (film thickness) and UV-visible spectroscopy is described. The third order nonlinear optical susceptibility of the nanocomposites was investigated in the visible region by refractive index dispersion measurements and the results are discussed. 17 refs. Ukraine Institute of Physics; Kiev Institute of Physical Chemistry; CEA-Saclay EU; EUROPEAN COMMUNITY; EUROPEAN UNION; FRANCE; UKRAINE; WESTERN EUROPE; WESTERN EUROPE-GENERAL

Accession no. 940437 Item 225 Macromolecular Symposia No.222, 2005, p.163 PREPARATION AND CHARACTERIZATION OF INTERPENETRATING POLYMER HYDROGELS BASED ON POLY(ACRYLIC ACID) AND POLY(VINYL ALCOHOL) Hernandez R; Lopez D; Perez E; Mijangos C The synthesis of interpenetrating polymer hydrogels of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) by a sequential process involving firstly crosslinking copolymerisation of acrylic acid and NN'methylenebisacrylamide in the presence of PVA followed



by a freeze-thaw procedure to form the PVA hydrogel within the PAA hydrogel is described. The products were characterised by swelling viscoelastic properties and carbon-13 NMR and the results are discussed. 7 refs. Madrid Instituto de Ciencia y Tec.de Polim.

is critical for the design and development of consumer products. The research efforts at the USDA laboratory pertaining to the development of biopolymer blends polymer processing characterisation and lifetime evaluation are presented. 14 refs.

EU; EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE; WESTERN EUROPE-GENERAL

USA


Accession no. 940406 Item 226 International Polymer Science and Technology 31, No.9, 2004, p.T/47-50 ACID HYDROLYSIS OF VINYL ACETATE IN AN AQUEOUS MEDIUM IN THE PRESENCE OF NON-IONOGENIC SURFACTANTS AND POLYVINYL ALCOHOL Karamyan D R; Sergeeva C N; Beileryan N M; Voskanyan P S; Eritsyan V K; Gevorkyan L A This article considers the use of emulsion polymerisation for the production of vinyl acetate copolymers and the incorporation of non-ionogenic surfactants for the initiation of polymerisation. In order to ensure an acceptable rate of decomposition of the initiating system use is made of additives and in particular acids to regulate the pH value of the reaction mixture. It is known that vinyl acetate undergoes hydrolysis in an aqueous medium with the formation of acetaldehyde and acetic acids which have a negative effect both on the polymerisation process and on the quality of the polyvinyl acetate formed. Work was carried out to study the hydrolysis of vinyl acetate in an aqueous medium under the conditions of polymerisation and the effect on hydrolysis of the components of the reaction system at working concentrations. Results are given of an investigation of the rates of acid hydrolysis of vinyl acetate in an aqueous medium in the presence of non-ionogenic surfactants. 5 refs. (Article translated from Plasticheskie Massy No.1 2004 pp.22). RUSSIA

Accession no. 937776 Item 227 Proceedings of the 62nd SPE Annual conference (ANTEC 2004) held Chicago Il p.2437 CHARACTERISTICS AND PERFORMANCE OF STARCH-POLY-(VINYL ALCOHOL) (PVA) BLENDS WITH AGRICULTURAL WASTE FIBER Imam S H; Glenn G M; Shey J; Clamczynski A; Wood D; Nguyen T; Cornish K; Orts W J The renewable polymers are environmentally friendly and naturally biodegradable and could serve as an inexpensive source of raw material for single-use engineered products. Efforts are underway to develop ecocompatible consumer plastics by incorporating renewable polymers as an alternative to petroleum-derived chemicals. Therefore gaining fundamental understanding of biobased polymers


Item 228 Polymer 45, No.26, 2004, p.8801 GEL SPINNING OF PVA/SWNT COMPOSITE FIBER Zhang X; Liu T; Sreekumar T V; Kumar S; Hu X; Smith K An optically homogeneous dispersion of single wall carbon nanotubes (SWNT) and polyvinyl alcohol (PVA) was prepared in DMSO/water by stirring and sonication. The dispersion was extruded into composite fibres into methanol via gel spinning and the tensile and dynamic mechanical properties of the dried fibres were determined. UV visible and Raman spectroscopy wideangle X-ray diffraction and SEM were also carried out. The modulus of the PVA/SWNT (3 wt%) composite fibre was 40% higher than that of a control fibre spun from PVA gel. PVA orientation in the control and composite fibres was similar but the composite fibres exhibited lower crystallinity. 39 refs. Georgia Institute of Technology; Carbon Nanotechnologies Inc. USA

Accession no. 937376 Item 229 Polymer 45, No.26, 2004, p.8779 POLY(VINYL ALCOHOL) HYDROGEL FIXATION ON POLY(ETHYLENE TEREPHTHALATE) SURFACE FOR BIOMEDICAL APPLICATION Li Y; Neoh K G; Kang E T Poly(vinyl alcohol) (PVA) hydrogel was immobilised onto a surface-functionalised poly(ethylene terephthalate) (PET) film to improve the film biocompatibility. The film was subjected to an argon plasma glow discharge then graft copolymerised with poly(ethylene glycol) monomethacrylate in the presence of ethylene glycol dimethacrylate as crosslinker before oxidisation with acetic anhydride-DMSO to produce aldehyde groups on the PET surface. ATR FTIR and X-ray photoelectron spectroscopy were used to study the surface at each stage. The aqueous PVA solution containing formaldehyde as crosslinker was covalently immobilised on the film by heating at 50 degC for eight hours. SEM was used to confirm the strong attachment. Heparin was immobilised on the PVA-covered PET by physical entrapment or covalent

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bonding to improve the biocompatibility of the film. The biocompatibilities of the various surface-modified PET films were evaluated by plasma recalcification time and blood platelet adhesion measurements. 41 refs. Singapore National University SINGAPORE

Accession no. 937374 Item 230 Proceedings of the 62nd SPE Annual conference (ANTEC 2004) held Chicago Il p.1451 INFLUENCE OF NANOPARTICLES ON THE SHRINKAGE CONTROL OF LOW PROFILE UNSATURATED POLYESTER COMPOSITES Liqun Xu; Lee L J Unsaturated polyester(UP) resins are one of the most widely used materials in fabricated composites. However a number of problems caused by their high polymerisation shrinkage have limited their growth in many new markets. The authors' research results showed that 1 to 3 wt % of nanoclay can provide excellent volume shrinkage control of UP resin systems containing polyvinyl acetate as a low profile additive(LPA) in room temperature moulding processes. Nanoclay residing in the LPA-rich phase led to a higher reaction rate and earlier onset of micro-cracking in the resin system. Consequently an earlier volume expansion during curing was observed in the reactive dilatometry experiment resulting in better shrinkage control. 8 Refs. USA

Accession no. 935598 Item 231 Proceedings of the 62nd SPE Annual conference (ANTEC 2004) held Chicago Il p.1810 SOME STUDIES ON MONTMORILLONITE(MMT) FILLED POLYPROPYLENE COMPOSITE SYSTEMS Li R K Y; Shi D Two aspects of PP/MMT composite systems are considered. In the first part the effect of using MMT particles as the initiator carrier in the melt grafting reaction of maleic anhydride(MAH) onto PP backbone is presented. It was found that using this method the degradation of the PP molecular chains can be significantly reduced. In the second part a method of improving the dispersion of MMT particles in PP/MMT nanocomposites is presented. This new method involves the pretreatment of MMT particles with PVA and the results show that the method is effective in improving the dispersion of MMT particles in PP matrix. 9 refs. CHINA; HONG KONG


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Item 232 Journal of Materials Science 40, No.3, 2005, p.777 NONLINEAR REFRACTION OF COOMASSIE BRILLIANT BLUE DYE IN PVA MATRIX Valsalamilka B; Sreekumar G; Muneera C I; Sendhil K; Vijayan C The organic chromophore Coomassie Brilliant Blue R-250 was prepared in solid film form in a PVAl matrix and investigated by the Z-scan technique using a laser beam. The chromophore exhibited a negative refractive nonlinearity and a non-linear coefficient of refractive index at a wavelength of 632.8 mm of 2.45 times 10 to the power 12 sq.m2/w. 11 refs. Kerala University; Indian Institute of Technology INDIA

Accession no. 935244 Item 233 Polymer 46, No.4, 2005, p.1379 GRAFTING AND ADSORPTION OF POLY(VINYL) ALCOHOL IN VINYL ACETATE EMULSION POLYMERIZATION Carra S; Sliepcevich A; Canevarolo A; Carra S The role of PVAl as a protective colloid in the emulsion polymerisation of vinyl acetate was investigated using various polyvinyl alcohols. The effect of PVAl blockiness on emulsion polymerisation and latex properties was examined and the rheological properties of the various latices obtained determined. Fractions of PVAl in the final latex were separated using a selective solubilisation procedure and the results obtained compared with those for the adsorption of PVAl onto emulsifier-free PVAc dispersions. 12 refs. Mapei SpA; Milano Politecnico EU; EUROPEAN COMMUNITY; EUROPEAN UNION; ITALY; WESTERN EUROPE; WESTERN EUROPE-GENERAL

Accession no. 934216 Item 234 Chemistry of Materials 17, No.1, 2005, p.9 NANOPARTICLE-EMBEDDED POLYMER: IN SITU SYNTHESIS FREE-STANDING FILMS WITH HIGHLY MONODISPERSE SILVER NANOPARTICLES AND OPTICAL LIMITING Porel S; Singh S; Harsha S S; Rao D N; Radhakrishnan T P The fabrication of free-standing films of silver nanoparticleembedded poly(vinyl alcohol)(PVA) by spin-coating an aqueous solution containing silver nitrate and PVA onto quartz or polystyrene-coated glass substrates followed by thermal treatment is described. The films were characterised by TEM plasmon absorption and nonlinear optical properties and the results are discussed. 19 refs.



Hyderabad University; Hyderabad Centre for Cellular and Molecular Biology INDIA

Accession no. 933909 Item 235 Polymers and Polymer Composites 12, No.7, 2004, p.561 RHEOLOGICAL PROPERTIES OF HIGH MOLECULAR WEIGHT POLY(VINYL ALCOHOL)/DIMETHYL SULFOXIDE/WATER CONCENTRATED SOLUTIONS Sung Jun Lee; Jin Woo Kwak; Hyo Dae Kim; Han Yong Jeon; Joon Ho Kim; Won Sik Yoon; Won Seok Lyoo Before carrying out gel spinning of polyvinyl acetate (PVA) to prepare high-performance PVA fibres the rheological properties of solutions of high molecular weight PVA in dimethyl sulphoxide(DMSO)/water mixtures was studied with various polymer concentrations at various temperatures. Polymer concentration and solution temperature was shown to play a significant role in the rheological behaviour of high molecular weight PVA solutions. Over the frequency range examined PVA solutions showed shear thinning behaviour at lower temperatures and as the polymer concentration was increased the extent of shear thinning also increased. In the plot of storage modulus of PVA solution with loss modulus the slope was less than 2 indicating that the phase of PVA solutions in DMSO/water is heterogeneous. 21 refs. Yeungnam University; Kolon Industries Inc.; Chonnam National University KOREA

Accession no. 933607 Item 236 ACS Polymeric Materials: Science and Engineering, Spring Meeting 90, 2004, p.746 ULTRASONIC INITIALLY CATALYZED EMULSION POLYMERIZATION OF VINYL ACETATE BY USING REDOX INITIATOR Bahattab M A Saudi Ultrasonic energy was used to initiate emulsion polymerisation of vinyl acetate at room temperature and using a non-thermal redox initiator in the absence of inert gas. The initiator was a mixture of ferrous sulphate heptahydrate sodium persulphate and sodium metabisulphite. A combination of ultrasonic energy and redox initiator was shown to result in higher conversion and higher rate of polymer production compared with using redox initiator alone. 12 refs. SAUDI ARABIA



Item 237 European Polymer Journal 41, No.2, 2005, p.329 STUDIES ON THE VISCOSITY BEHAVIOR OF POLYMER SOLUTIONS AT LOW CONCENTRATIONS Haiyang Yang; Yunfei Yan; Pingping Zhu; Hao Li; Qingren Zhu; Chenggao Fan The viscosities of solutions of poly(vinyl alcohol) (PVA) poly(N-vinyl-2-pyrrolidone) (PVP) and poly(ethylene oxide) (PEO) were measured down to low concentrations. The flow time of the pure solvent in ideal conditions (t0(asterisk)) obtained by extrapolating the flow time of polymer solution t to zero concentration was not equal to the flow time of the pure solvent (t0). The reduced viscosity calculated as (t/t0 - 1)/C (where C is the concentration) exhibited either a marked increase or a significant decrease with dilution depending on the polymer solution investigated. On the other hand the reduced viscosity calculated as (t/t0(asterisk) - 1)/C was proportional to C even at low concentrations. The anomalous viscosity behaviour of neutral polymer solutions at low concentrations is therefore a result of an incorrect method for calculating the reduced viscosity. The effective diameter of the viscometer capillary the surface properties of the capillary wall and the additional pressure corresponding to the measurement of t and t0 were different for PVA PVP and PEO solutions. By taking into account the contact angle and the surface tension of the liquid together with the geometric parameters for the viscometer the effect of the additional pressure on the flowtime measurement could be studied quantitatively. The thickness of the adsorbed polymer layers on the capillary walls was markedly affected by the nature of the solvent in which the polymer molecules were dissolved whereas molecular weight of the polymer had little or no effect on the thickness of the adsorbed layers of polymer on the walls of the viscometer capillary. 45 refs. China University of Science & Technology CHINA

Accession no. 932585 Item 238 CSIC Macromolecules 37, No.25, 2004, p.9620 CONTROLLING PVA HYDROGELS WITH GAMMA-CYCLODEXTRIN Hernandez R; Rusa M; Rusa C C; Lopez D; Mijangos C; Tonelli A E Details are given of the preparation and characterisation of PVAL hydrogels formed during freeze-thaw cycles of their aqueous solutions containing gamma-cyclodextrin. Confirmation of the existence of the channel structure for gamma-cyclodextrin was achieved by characterising the dried hydrogels with solid-state DSC TGA wide-angle X-ray diffraction and carbon 13C-NMR. Swelling and rheological responses are discussed. 20 refs.

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EU; EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; USA; WESTERN EUROPE; WESTERN EUROPE-GENERAL

EU; EUROPEAN COMMUNITY; EUROPEAN UNION; GERMANY; WESTERN EUROPE; WESTERN EUROPEGENERAL



Item 239 Polymer International 53, No.12, 2004, p.2138 SYNTHESIS AND CHARACTERIZATION OF COPOLYMERS OF POLY(VINYL ALCOHOL) WITH THIOPHENE SIDE-GROUPS AND PYRROLE Sahmetlioglu E; Yuruk H; Toppare L; Canga I; Yagci Y

Item 241 Journal of Polymer Science: Polymer Chemistry Edition 42, No.24, 2004, p.6331 ULTRAFINE HYDROGEL FIBERS WITH DUAL TEMPERATURE- AND PH-RESPONSIVE SWELLING BEHAVIORS Hong Chen; You-Lo Hsieh

North Carolina State University;

Graft copolymers of polyvinyl alcohol with thiophene side-groups and pyrrole are synthesised by electrochemical polymerisation methods. Polyvinyl alcohol with thiophene side-groups (PVATh) is obtained from the reaction between polyvinyl alcohol (PVA) and thiophene-3-acetic acid. The syntheses of copolymers of PVATh and pyrrole are achieved electrochemically by using three different supporting electrolytes p-toluene sulphonic acid (PTSA) sodium dodecyl sulphate (SDS) and tetrabutylammonium tetrafluoroborate (TBAFB). Characterisation of PVATh and graft copolymers is performed by a combination of techniques including cyclic voltammetry scanning electron microscopy thermal gravimetry differential scanning calorimetry size exclusion chromatography 1H-NMR and FT-IR. The conductivities are measured by the four-probe technique. 11 refs. Turkey Nigde University; Ankara Middle East Technical University; Istanbul Technical University TURKEY

Accession no. 931499 Item 240 Colloid and Polymer Science 283, No.1, 2004, p.24 HYDROGELS IN AQUEOUS PHASES OF POLYVINYLALCOHOL(PVA) SURFACTANTS AND CLAY MINERALS Jing Liu; Hoffmann H Aqueous dispersions of a synthetic clay mineral were shown to be transformed by amphiphilic water-soluble polymers such as PVAl into soft gels. The polymer bonded onto the clay mineral and the adsorbed coils acted like crosslinking agents between the clay mineral particles. The resulting gels had a yield stress value and a frequencyindependent storage modulus. Under saturation the clay mineral particles could adsorb five times their own weight of PVAl. Anionic surfactant adsorbed on PVAl and rendered it hydrophilic. As a consequence PVAl could no longer bind to the clay mineral and the gels were transformed into low viscosity aqueous solutions. 21 refs. Bayreuth University

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Ultrafine hydrogel fibres responsive to both temperature and pH signals were prepared by electrospinning of mixtures of poly(N-isopropylacrylamide) (PNIPAAm) and poly(acrylic acid) in DMF. Both the diameters and packing of the fibres could be controlled by changing the polymer compositions and the molecular weights of PNIPAAm. These fibres were rendered water-insoluble by the addition of either disodium phosphate or poly(vinyl alcohol) (PVA) to the solution followed by heat curing of the fibres. The fibres crosslinked with disodium phosphate swelled to 30-120 times in water; this was significantly more than the swelling of fibres crosslinked with PVA. The PVA-crosslinked hydrogel fibres however showed more rapid swelling reaching equilibrium in less than 5 min at 25 deg C. They were also more stable after 1 week of water exposure. All the hydrogel fibres showed a marked increase in swelling between pH 4 and 5. The PVA-crosslinked hydrogel fibres exhibited distinct temperature-responsive phase-transition behaviour of PNIPAAm whereas the disodium phosphate-crosslinked hydrogel fibres showed altered two-stage phase transitions that reflected side-chain modification of PNIPAAm. 27 refs. California University at Davis USA

Accession no. 930384 Item 242 ACS Polymeric Materials: Science and Engineering, Fall Meeting 89, 2003, p.774 EFFECTS OF REACTIVE VINYL ACETATEBASED BLOCK COPOLYMERS ON THE SHRINKAGE AND INTERNAL PIGMENTABILITY FOR LOW-TEMPERATURE CURE OF UNSATURATED POLYESTER Huang Y-J; Dong J-P; Chiu S-G; Hsu M-W Details are given of the effects of reactive vinyl acetatebased block copolymer types of low profile additives on the volume shrinkage characteristics and internal pigmentability for styrene/unsaturated polyester/additive ternary systems cured at low temperatures. Cure kinetics were determined by DSC and morphology of fractured surfaces were examined using SEM. Volume shrinkage



and colour depth were measured by density measurements and by using a chromameter. 13 refs. CHINA

Accession no. 929526 Item 243 E-Polymers No.78, 2004, p.1 ELECTROSPUN POLY(VINYL ALCOHOL)/ POLY(ACRYLIC ACID) FIBRES WITH EXCELLENT WATER-STABILITY Zeng J; Hou H; Wendorff J H; Greiner A The effects of annealing with poly(acrylic acid)(PAA) on the water stability of electrospun poly(vinyl alcohol) (PVA) nanofibres were investigated by measurement of the swelling of solution-cast PVA/PAA films. The results are discussed in terms of the effects of reaction conditions including PVA/PAA ratio annealing temperature and time PAA molecular weight and use of an esterification catalyst on the water stability of electrospun PVA/PAA composite nanofibres. 11 refs. Marburg Philipps University EU; EUROPEAN COMMUNITY; EUROPEAN UNION; GERMANY; WESTERN EUROPE; WESTERN EUROPEGENERAL

Accession no. 929436 Item 244 Polymer Bulletin 52, No.3-4, 2004, p.201 PREPARATION OF MECHANICALLY CROSSLINKED POLY(VINYL ALCOHOL) Kubo M; Hayakawa N; Minami Y; Tamura M; Uno T; Itoh T A novel cyclic macromonomer based on a cyclic PS is prepared. Its radical copolymerisation with vinyl acetate is carried out to give a mechanically crosslinked polyvinyl acetate which is converted to a mechanically crosslinked polyvinyl alcohol with high swellability. 9 refs. Mie University JAPAN

Accession no. 929313 Item 245 T3 Technical Textile Technology 3, No.3, 2004, p.20 NEW DOORS OPEN FOR COPOLYESTER ELASTOMER IN PADS AND COATINGS Dusaj S; Karandikar A Market needs are reported to have opened the door to new applications for copolyester elastomer. In one case this involves a call for reusable incontinence pads that cost less to maintain. Here a new pad construction having a barrier layer of Riteflex copolyester thermoplastic elastomer (COPE/TPE) lowers washing costs compared with the


predominant pads having PVC barriers. Another case involves the need for non-skid surfaces coated on fabrics that withstand industrial washing. Here Riteflex COPE/ TPE provides an alternative this time by replacing PVOH and EVA. Details are given. Precision Custom Coating; Ticona Corp. USA

Accession no. 929306 Item 246 Journal of Applied Polymer Science 94, No.6, 2004, p.2356 PREPARATION OF HIGH MOLECULAR WEIGHT POLY(VINYL ALCOHOL) WITH HIGH YIELD BY EMULSION POLYMERIZATION OF VINYL ACETATE USING 2,2'-AZOBIS(2AMIDINOPROPANE) DIHYDROCHLORIDE Won Seok Lyoo; Jin Woo Kwak; Kyu Ha Choi; Seok Kyun Noh Preparation of high molecular weight polyvinyl alcohol PVAl and polyvinyl acetate (PVAc) shell/PVAl core microspheres by saponification of PVAc previously emulsion polymerised with an azo-initiator 2,2'-azobis(2amidinopropane) dihydrochloride is described. Polymers prepared using this route were of higher molecular weight than those prepared using potassium persulphate as initiator. Characterisation of molecular weight was carried out by determination of intrinsic viscosity and calculation and morphology of microspheres by scanning electron microscopy. 32 refs. Yeungnam University KOREA

Accession no. 928530 Item 247 Plastics Technology 50, No.10, 2004, p.32 PVOH FOR BLOWN FILM AND INJECTION MOLDING A. Schulman Inc. of the USA has formulated a new extrudable polyvinyl-alcohol compound especially for blown films to be used in the place of solution-cast polyvinyl-alcohol films. The waster-soluble polymer known as AquaSol is also undergoing injection moulding field trials in applications where LDPE is typically used and there is a need for a biodegradable material. SCHULMAN A.INC. USA

Accession no. 928021 Item 248 Polymer 45, No.24, 2004, p.8201 DEGREE OF CROSSLINKING AND MECHANICAL PROPERTIES OF

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CROSSLINKED POLY(VINYL ALCOHOL) BEADS FOR USE IN SOLID-PHASE ORGANIC SYNTHESIS Gauthier M A; Luo J; Calvet D; Ni C; Zhu X X; Garon M; Buschmann M D The degree of crosslinking of swellable hydrophilic gel beads of poly(vinyl alcohol) (PVA) prepared with different quantities of epichlorohydrin (EP) crosslinker in the feed were examined by spectroscopic and chemical methods. Raman spectroscopy showed that the vast majority of EP crosslinks were monomolecular and doubly bonded to PVA. This allowed the degree of crosslinking to be determined by NMR spectroscopy and by titrating the functional group loading of the polymer before and after crosslinking. Single-bead unconfined compression studies showed that PVA with a 1:1 PVA/EPA ratio had a higher shear modulus than that with a 1:2 PVA/EPA ratio as a result of the increased cross-link density. PVA-EP beads swollen in water and DMF had significantly lower shear moduli than the model polystyrene-divinylbenzene beads as a result of their considerable degree of swelling in aqueous or polar media. 37 refs. Montreal University; Montreal Ecole Polytechnique CANADA

Accession no. 927301 Item 249 ASTM D 4317. SPECIFICATION FOR POLYVINYL ACETATE-BASED EMULSION ADHESIVES Version 98 (R2004). Photocopies and loans of this document are not available from Rapra. USA

Accession no. 925234 Item 250 Journal of Applied Polymer Science 93, No.4, 2004, p.1638 ROLE OF MOLECULAR WEIGHT OF ATACTIC POLY(VINYL ALCOHOL) (PVA) IN THE STRUCTURE AND PROPERTIES OF PVA NANOFABRIC PREPARED BY ELECTROSPINNING Joon Seok Lee; Kyu Ha Choi; Han Do Ghim; Sam Soo Kim; Du Hwan Chun; Hak Yong Kim; Won Seok Lyoo Two different atactic PVAL nanofabrics prepared by electrospinning from two atactic PVALs with numberaverage degrees of polymerisation of 1700 or 4000. The process parameters such as electrical field tip-to-collector distance and solution concentration were varied and optimum electrospinning conditions were determined by morphological investigations. The nanofabric produced from the atactic PVAL of higher molecular weight showed superior crystalline properties thermal stability and mechanical properties. 29 refs.

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Yeungnam University; Chonbuk National University KOREA

Accession no. 924441 Item 251 Polymer 45, No.21, 2004, p.7193 CHARACTERIZATION OF POLY(VINYL ALCOHOL)/POLY(ETHYLENE GLYCOL) HYDROGELS AND PVA-DERIVED HYBRIDS BY SMALL-ANGLE X-RAY SCATTERING AND FTIR SPECTROSCOPY Mansur H S; Orefice R L; Mansur A A P Novel poly(vinyl alcohol) (PVA)/poly(ethylene glycol) (PEG) hydrogel blends and PVA-derived organic-inorganic hybrid materials were prepared and nanostructurally characterised. PVA and PEG hydrogels were prepared treating aqueous solutions of the polymer with glutaraldehyde (GA) as a chemical crosslinker. Hybrids were prepared by treating aqueous solutions of PVA with tetraethoxysilane (TEOS). PVA/TEOS hybrids were also modified on the nanometer scale by crosslinking with GA during the synthesis reaction. Small-angle X-ray scattering studies indicated different nano-ordered disperse phases for hydrogels made of PVA PEG PVA/GA and PVA/PEG. PVA/TEOS and PVA/TEOS/GA hybrids also showed different X-ray scattering patterns. 24 refs. Minas Gerais Universidade Federal BRAZIL

Accession no. 924049 Item 252 Polymer 45, No.21, 2004, p.7129 PREPARATION AND MAGNETOMETRIC CHARACTERIZATION OF IRON OXIDECONTAINING ALGINATE/POLY(VINYL ALCOHOL) NETWORKS Nishio Y; Yamada A; Ezaki K; Miyashita Y; Furukawa H; Horie K Alginate-based magnetic gels were prepared by sequential crosslinking of alginate in aqueous ferrous salt solution immersion of the resulting gels in a solution of an alkaline earth metal and treatment of the partially cation-exchanged gels with hydrogen peroxide. Magnetometry measurements showed that the lyophilised gels had superparamagnetism or ferromagnetism at room temperature depending on the type of metallic cation used in the alkali treatment. Interpenetrating network (IPN)-type alginate/poly(vinyl alcohol) (PVA) gels containing iron oxides were also prepared from mixed polymer solutions by a modified preparation method in which the gelation and alkali treatment were performed by using a metallic borate. The viscoelasticity of the magnetic IPN composites in the gelatinous state could be controlled by changing the ratio of alginate to the PVA. The magnetic characteristics



of the IPN varied on changing the alginate/PVA ratio the alkaline reagent and the temperature. 24 refs. Kyoto University; Tokyo University of Agriculture & Technology JAPAN

Accession no. 924041 Item 253 China Synthetic Fiber Industry 27, No.4, 2004, p.31 DISCUSSION ON PROCESS TECHNOLOGY OF WATER-SOLUBLE PVA FIBER VIA WET SPINNING Yun H The preparation of water-soluble PVAl fibre feedstock selection spinning solution preparation spinning and posttreatment conditions are discussed. Conditions for the production of water-soluble PVAl fibres having a dissolution temperature higher than 60C are described. 1 ref. SINOPEC; Sichuan Vinylon Works CHINA

Accession no. 923428 Item 254 Analytica Chimica Acta 519, No.2, 2004, p.147 POLYMERIC PH INDICATORS IMMOBILIZED PVA MEMBRANES FOR OPTICAL SENSORS FO HIGH BASICITY BASED ON KINETIC PROCESS Liu Z; Luo F; Chen T Two kinds of polymeric pH indicators PPF (phenolphthaleinformaldehyde product) and CPF (ortho-cresolphthaleinformaldehyde product) immobilised crosslinked polyvinyl alcohol membranes (PPF-PVA and CPF-PVA) for optical intermittent determination of high basicity ((OH) = 1-8 M) based on a kinetic process are developed. It has previously been demonstrated that PPF-PVA and CPF-PVA can perform the determination of high pH values from pH 10 to 14. The discolouring kinetic behaviours of PPF-PVA and CPF-PVA are compared with those of free phenolphthalein ortho-cresolphthalein and thymolphthalein. Experimental results and theoretical analysis indicate that the response behaviours of the optodes' membranes in concentrated NaOH solutions are diffusion independent and still comply with the pseudo-first-order kinetics. In addition two data analysis methods for determination are presented. One is directly based on the reduced absorbance; the other is based on the discolouring kinetic constant. It is found that the latter can perform a rapid (60 s) and reliable (relative standard deviation: 2.6%) determination for high basicity. These kinds of optodes can be used repeatedly when they are immersed in low-pH solutions to regain the protonated form after each determination. Chinese Academy of Sciences CHINA



Item 255 Polymer 45, No.17, 2004, p.5863 SYNTHESIS AND CHARACTERIZATION OF HYDROPHOBICALLY MODIFIED POLY(VINYL ALCOHOL) HYDROGEL MEMBRANE Gholap S G; Jog J P; Badiger M V A series of hydrophobically modified poly(vinyl alcohol) (PVA) samples were synthesised by graft copolymerisation of N-tert-butylacrylamide [NTBA] onto PVA by freeradical polymerisation. Membranes were cast from solutions of the copolymers in dimethyl sulphoxide. The increase in hydrophobicity with increasing NTBA content was investigated by contact-angle measurements. The swelling behaviour of membranes was studied as a function of temperature hydrophobic content annealing temperature and period. The permeability of solutes through the membranes was investigated as a function of solute size membrane hydrophobicity and temperature. The swelling behaviour of the copolymer membranes showed that a lower content of NTBA gives discontinuous volume transition with respect to temperature whereas the presence of higher amounts of NTBA produced a decrease in the swelling ratios. The permeabilities of solutes through these membranes were strongly dependent on the size of the solute the solution temperature and hydrophobicity of the membrane. 29 refs. Pune National Chemical Laboratory INDIA

Accession no. 922416 Item 256 Polymer 45, No.7, 2004, p.2381 CHARACTERISTIC RHEOLOGICAL FEATURES OF PVA SOLUTIONS IN WATER-CONTAINING SOLVENTS WITH DIFFERENT HYDRATION STATES Song S I; Kim B C The rheological properties of poly(vinyl alcohol) (PVA) solutions of different concentrations in mixtures of water with dimethyl sulphoxide or N-methylmorpholine N-oxide were investigated and compared using parallelplate rheometry. The results are discussed in terms of the effects of the hydration state of the solvents ie the degree of association of the water content on the rheological and other physical properties such as gelation of the PVA solutions. 22 refs. Hanyang University SOUTH KOREA

Accession no. 921477 Item 257 CNIC Polymer 45, No.16, 2004, p.5543

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VISCOELASTIC PROPERTIES OF POLY(VINYL ALCOHOL) HYDROGELS AND FERROGELS OBTAINED THROUGH FREEZING-THAWING CYCLES Hernandez R; Sarafian A; Lopez D; Mijangos C Poly(vinyl alcohol) (PVA) hydrogels were prepared by freezing-thawing cycles and their viscoelastic properties in the parallel-plate shear mode were evaluated as a function of temperature time degree of swelling concentration and the number of freezing-thawing cycles. The storage modulus was analysed in relation to a theoretical model based on the scaling approach. The results confirm the noncrystalline nature of PVA cryogels. PVA ferrogels were also prepared from aqueous solutions of PVA and a ferrofluid through freezing-thawing cycles and their viscoelastic properties were examined. The variation of the storage modulus with the ferrofluid concentration cannot be fitted by using classical theories. This was attributed to the small dimensions of the particles in the ferrogels and to the magnetic interactions between the particles. 28 refs. EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE Accession no. 920495 Item 258 Polymer 45, No.16, 2004, p.5407 SPECTROSCOPIC INVESTIGATIONS OF MN2+ IONS DOPED POLYVINYLALCOHOL FILMS Kumar G N H; Rao J K; Gopal N O; Narasimhulu K V; Chakradhar R P S; Rajulu A V Mn2+ ions doped in poly(vinyl alcohol) (PVA) films were examined by electron paramagnetic resonance (EPR) luminescence and infrared spectral studies. The room-temperature EPR spectra exhibit sextet hyperfine structure centred at an effective g factor of approximately 2.0 characteristic of Mn(2+) ions in octahedral symmetry. The zero-field splitting parameter at room temperature was evaluated from the intensities of allowed hyperfine lines. The EPR spectra exhibit a marked concentration dependence. The paramagnetic susceptibility (chi) was calculated from the EPR data at various temperatures. The Curie constant and Curie temperature were evaluated from a plot of 1/chit. The emission spectrum of Mn(2+) ions doped PVA film exhibited three bands centred at 390 448 and 465 nm. The bands at 390 and 465 nm were attributed to recombination of free charge carriers whereas the band at 448 nm was attributed to the 4T1g to 6A1g transition of Mn(2+) ions. The excitation spectrum showed two bands at 250 and 216 nm attributed to host lattice absorption bands. 31 refs. Sri Venkateswara University; Weizmann Institute of Science; Indian Institute of Science; Anantapur S.K.University INDIA; ISRAEL


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Item 259 Journal of Applied Polymer Science 93, No.3, 2004, p.1264 BITHIAZOLE-CONTAINING POLYMERIC COMPLEX AND PVA COMPOSITE FILM: PREPARATION AND MAGNETIC PROPERTIES Lin C; Sun W; Jiang L; Wang L; Shen Z The synthesis of bisthiazole-containing amide polymers and their corresponding metal complexes and the preparation of solution-cast composite films of the complexes with poly(vinyl alcohol) in various proportions and their characterisation by FTIR is described. The magnetic properties of the complexes and composite films were investigated and the results are discussed. 17 refs. Zhejiang University CHINA

Accession no. 919946 Item 260 Journal of Applied Polymer Science 93, No.3, 2004, p.1151 THERMAL PROPERTIES OF POLY(VINYL ALCOHOL)-SOLUTE BLENDS STUDIED BY TMDSC Stavropoulou A; Papadokostaki K G; Sanopoulou M The thermal properties of blends of semi-crystalline poly(vinyl alcohol) (PVA) with a drug substance buflomedil pyridoxal phosphate (BPP) in various proportions were investigated by temperature-modulated DSC and TGA. The effects of the dispersion of BPP in the PVA matrix on glass transition temperature melting temperature crystallinity and thermal stability of the blends is discussed in terms of specific interactions between the polar groups of the two components. 16 refs. Athens Democritos National Research Center EUROPEAN COMMUNITY; EUROPEAN UNION; GREECE; WESTERN EUROPE

Accession no. 919932 Item 261 Macromolecules 37, No.9, 2004, p.3180 GRAFTING OF PVA IN MINIEMULSION COPOLYMERIZATIONS OF N-BUTYL ACRYLATE AND METHYL METHACRYLATE USING WATER-SOLUBLE PARTIALLY WATERSOLUBLE AND OIL-SOLUBLE INITIATORS Kim N; Sudol E D; Dimonie V L; El-Aasser M Mini-emulsion copolymerisations of methyl methacrylate and n-butyl acrylate initiated with water-soluble (hydrogen peroxide HPO) partially water soluble (tert-butyl peroxide TBHP) and oil soluble (tert-butyl peroctoate TBPO) initiators were carried out to study the grafting of PVAL at the oil/water interface. The amounts of grafted PVAL produced in the mini-emulsion copolymerisations initiated with TBHP and TBPO were considerably less than



those produced in the corresponding seeded emulsion polymerisations. The amount of grafted PVAL in seeded emulsion polymerisations initiated with TBHP decreased with increasing monomer/polymer ratio. In mini-emulsion polymerisations initiated with TBPO the grafting occurred mainly in the later stages of the polymerisation. These results supported the idea that the different internal viscosities at the interface may affect the termination reactions between primary radicals and PVAL macro radicals thus resulting in different degrees of grafting. In mini-emulsion polymerisation it was found that aqueous phase and interface grafting occurred in the HPO system but that interface grafting dominated in the TBHP system. Also the grafted PVAL in the TBHP system was still soluble which indicated that the grafted chains were short. The results were discussed. 16 refs. Lehigh University

in water. The major types of intermolecular interactions from inorganic salts are responsible for the network of PVA and water which ruptures the multiple H-bonds between the OH groups of the polymer chains; therefore various ions possessing abilities to affect these bonds result in salting out. It has been suggested that water molecules in the region of ionic hydration spheres must have strong orientation preferences which could considerably restrict their ability to reorient and form hydration shells around nearby non-polar solutes and thus affect the microstructure. The primary objective is to study the variation of surface tension as it reflects the change in short-range forces. The surface tension behaviour with the variation of concentration and temperature for different molecular weights of PVA is also studied. 17 refs.

USA

INDIA



Item 262 Proceedings of the 61st SPE Annual Conference (ANTEC 2003) held Nashville, TN p.1962 THERMOMECHANICAL CHARACTERIZATION OF BLENDS OF POLY(VINYL ACETATE) WITH SEMICRYSTALLINE POLYMERS FOR SHAPE MEMORY APPLICATIONS Liu C; Mether P T

Item 264 Journal of Applied Polymer Science 93, No.1, 2004, p.41 EFFECT OF MOLECULAR WEIGHT ON THE RHEOLOGICAL PROPERTIES OF ATACTIC POLY(VINYL ALCOHOL)/ DIMETHYLSULFOXIDE/WATER SOLUTION Lyoo W S; Lee S J; Kim J H; Noh S K; Ji B C; Kim B C

Miscible blends of amorphous poly(vinyl acetate) (PVAc) and semicrystalline polylactide were prepared by melt mixing and pressed into films. The blends were characterised by thermogravimetric analysis wide-angle X-ray scattering and dynamic mechanical studies. Shape recovery was studied by bending samples into a helical shape at 65 C then fixing the shape by quenching in iced water. Shape recovery was recorded by video camera when the deformed sample was immersed in warm water. Each blend exhibited a single glass transition temperature indicating miscibility. The degree of crystallinity decreased monotonically with increasing PVAc content. This controlled the rubbery moduli by acting as physical crosslinking points. 11 refs.

The molecular weight effect of atactic polyvinyl alcohol (a-PVA) on the rheological properties of 7.5 10.0 and 12.5 g/dL solutions of (a-PVA) with number-average degrees of polymerisation (Pn) of 4000 and 1700 in dimethyl sulphoxide/water mixture is described. a-PVA with a Pn of 1700 solutions exhibits almost Newtonian flow behaviour whereas high molecular weight a-PVA with a Pn of 4000 solutions exhibits shear-thinning behaviour. On the plot of storage and loss moduli of a-PVA with a Pn of 1700 solutions the dynamic storage modulus of PVA with a Pn of 1700 solutions is smaller than the dynamic loss modulus over the frequency range of 10-1 to 102 rad/s. However the dynamic storage modulus of PVA with a Pn of 4000 solutions ia smaller than the dynamic loss modulus in the sol state and in the post-gel state the dynamic storage modulus becomes larger than the dynamic loss modulus indicating the evolution of viscoelastic solid properties. 18 refs.

USA

Accession no. 918089 Item 263 Journal of Applied Polymer Science 93, No.1, 2004, p.122 STUDIES OF SURFACE TENSION OF POLY(VINYL ALCOHOL): EFFECT OF CONCENTRATION TEMPERATURE AND ADDITION OF CHAOTROPIC AGENTS Bhattacharya A; Ray P It is generally considered that the H-bonds are responsible for the stabilisation of network of polyvinyl alcohol (PVA)


India Central Salt & Marine Chem.Res.Inst.

Yeungnam University; Kyungpook National University; Hangyang University KOREA


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THE MECHANICAL PROPERTY AND PHASE STRUCTURES OF WHEAT PROTEINS/ POLYVINYL ALCOHOL BLENDS STUDIED BY HIGH-RESOLUTION SOLID-STATE NMR Zhang X; Burgar I; Lourbakos E; Beh H The effects of poly(vinyl alcohol)(PVOH) content on the phase structures and mechanical properties of blends of wheat proteins thermally processed with glycerol and water as plasticisers and PVOH were investigated using solid-state proton and carbon- 13C-NMR DMA (loss modulus storage modulus) and tensile testing (tensile strength elongation at break Young's modulus). The results are discussed in terms of intermolecular interactions between blend components. 47 refs. CSIRO Manufacturing and Infrastructure Technology AUSTRALIA

Accession no. 917116 Item 266 Journal of Membrane Science 240, No.1-2, 2004, p.37 PREPARATION AND CHARACTERIZATION OF CROSSLINKED PVA/SIO2 HYBRID MEMBRANES CONTAINING SULFONIC ACID GROUPS FOR DIRECT METHANOL FUEL CELL APPLICATIONS Kim D A; Park H B; Rhim J W; Lee Y M Organic-inorganic hybrids based on polyvinyl alcohol (PVOH)/SiO2 hybrid membranes containing sulphonic acid groups are prepared using the sol-gel process under acidic conditions. The PVOH/sulphosuccinic acid (SSA)/ silica hybrid membranes are fabricated from different SSA contents. The proton conductivity and methanol permeability of the hybrid membranes are studied with changing SSA content from 5 to 25 wt.%. It is found that the proton conductivity and the methanol permeability are dependent on the SSA content both as a crosslinking agent and as a donor of the hydrophilic SO3H group. Up to an SSA content of about 20 wt.% both of these properties decrease and above this SSA content they begin to increase with increasing SSA content. The proton conductivities of the PVOH/SSA/silica membranes are in the range of 103 to 102 S/cm and methanol permeabilities range between 108 and 107 cm2/s. The presence of silica particles in the organic polymer matrix which reduce the free water ratio of the membranes results in hybrids with markedly reduced methanol permeabilities. These characteristics of the PVA/ SSA/silica hybrid membranes are desirable for future applications related to direct methanol fuel cells. Hanyang University; Hannam University KOREA

Accession no. 916931 Item 267 Journal of Polymer Science: Polymer Physics Edition 42, No.8, 2004, p.1451

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RHEOLOGICAL PROPERTIES OF SOLUTIONS OF GENERAL-PURPOSE POLY(VINYL ALCOHOL) IN DIMETHYL SULFOXIDE Lee E J; Kim N H; Dan K S; Kim B C The rheological properties of solutions of atactic poly(vinyl alcohol) (PVA) in dimethyl sulphoxide were studied as a function of concentration and molecular weight. The syndiotactic dyad content and weight-average molecular weight of PVA were 52% and 85000-186000 respectively. The molecular weight had a minor effect on the rheological behaviour for 10-14 wt.% solutions but the concentration had a major influence indicating the importance of polar interactions through the hydroxyl groups. On a modified Cole-Cole plot the solutions gave various curves with slopes of less than 2 rather than a single master plot the slope decreasing marginally with increasing concentration. The deviation from the master curve indicated that the solutions were rheologically heterogeneous despite optical transparency. For 14 wt.% PVA solutions the loss tangent varied with the shear rate and produced three distinct regions which indicated a shear-induced double sol-gel transition as the shear rate increased over 0.05-500 rad/s. 24 refs. Sungshin Women's University; Hanyang University KOREA

Accession no. 916809 Item 268 Pharmaceutical Technology Europe 16, No.4, 2004, p.37/46 DEVELOPMENT OF PVA COPOLYMER CAPSULES Hoshi N; Ogura T; Shimamoto T; Uramatsu S The properties of a new copolymer polyvinyl alcohol acrylic acid methyl methacrylate copolymer and its suitability for the manufacture of capsules for drugs are examined. Copolymer properties considered include dissolution in various fluids film strength gas permeability moisture absorption and desorption. Capsule properties considered include dissolution disintegration hardness filling dissolution absorption of indomethacin in rats and tolerance. A comparison is also made of these capsules with conventional capsules. 9 refs. Nisshin Kasei Co.Ltd.; Daido Chemical Corp. JAPAN

Accession no. 916786 Item 269 Journal of Membrane Science 239, No.2, 2004, p.255 PERVAPORATION STUDIES OF GASEOUS PLASMA TREATED PVA MEMBRANE Upadhyay D J; Bhat N V A non-porous PVAl membrane was subjected to air nitrogen and oxygen plasma treatment to improve the



separation efficiency for azeotropic water-isopropanol mixtures and the permselectivity of the treated membrane investigated. Treatment time was optimised and used to study pervaporation performance over a selected waterisopropanol concentration range. The modified membranes were analysed by ATR-FTIR spectroscopy DSC and wide angle X-ray diffraction. Nitrogen plasma treatment was found to induce crosslinking on the membrane surface and to enhance separation performance. Ulster University; Bombay Textile Research Assn. EUROPEAN COMMUNITY; EUROPEAN UNION; INDIA; UK; WESTERN EUROPE

Accession no. 916603 Item 270 Journal of Sol-Gel Science and Technology 30, No.1, 2004, p.49 PREPARATION OF MACROPOROUS SOL-GEL BIOGLASS USING PVA PARTICLES AS PORE FORMER Jie Q; Lin K; Zhong J; Shi S; Li Q; Chang J; Wang R The synthesis of macroporous sol-gel bioglass by the addition of poly(vinyl alcohol) particles as pore former to the aqueous sol derived from tetraethoxysilane followed by heat treatment of the gel is described. The bioglass was characterised by SEM (morphology) surface area and porosity and its in vitro bioactivity was investigated by apatite layer formation in simulated body fluid using FTIR x-ray diffraction and field emission SEM. 25 refs. Shanghai Institute of Ceramics CHINA

Accession no. 916441 Item 271 Journal of Sol-Gel Science and Technology 29, No.2, 2004, p.107 SYNTHESIS AND CHARACTERIZATION OF POLYVINYL ALCOHOL (PVA)/SILICA HYBRID COMPOSITES DERIVED THROUGH THE SOLGEL METHOD IN AQUEOUS MEDIUM: EFFECT OF ACID CONTENT SILICA CONTENT AND VISCOSITY OF PVA ON THE DISPERSION CHARACTERISTICS OF SILICA AND THE PHYSICAL PROPERTIES OF THE COMPOSITES Kotoky T; Dolui S K The synthesis of poly(vinyl alcohol)/silica hybrid composites of various compositions in aqueous medium using the sol-gel process by the initial formation of a stable colloidal sol from sodium silicate is described. Composite films obtained by gelation were characterised by FTIR SEM TGA tensile strength elongation at break and water uptake measurements and the results are discussed. 22 refs. Napaam Tezpur University INDIA



Item 272 Polymer International 53, No.7, 2004, p.911 SELECTED PROPERTIES OF PH-SENSITIVE BIODEGRADABLE CHITOSAN-POLY(VINYL ALCOHOL) HYDROGEL Wang T; Turhan M; Gunasekaran S The properties of semi-interpenetrating polymer networks derived from chitosan and poly(vinyl alcohol)(PVA) with glutaraldehyde as crosslinking agent in various proportions were investigated by FTIR and fracture tests before and after swelling at different pH values. The effects of longer swelling times in acidic media on the leaching out of PVA are discussed in terms of the hydrolysis of the Schiff's base groups of the hydrogel. 25 refs. Wisconsin-Madison University; Mersin University TURKEY; USA

Accession no. 915601 Item 273 Canadian Journal of Chemical Engineering 81, No.3-4, 2003, p.566 GAS-LIQUID-SOLID REACTIONS OF POLYVINYL ALCOHOL ON OXIDATION TREATMENTS FOR ENVIRONMENTAL POLLUTION REMEDIATION Silva A M T; Vaz R N P; Quinta-Ferreira R M; Levec J Polyvinyl alcohol (PVA) oxidation in liquid-phase is studied in a batch high-pressure reactor at 140 to 240 deg.C and 0.7 MPa oxygen partial pressure. The two-phase (gas-liquid) non-catalytic wet oxidation is compared with a three-phase system (gas-liquid-solid) using CuO-ZnO/ Al2O3 and Mn-Ce-O oxides catalysts. Oxidation processes are shown to be quite promising technologies for industrial effluents containing PVA leading to high reductions in PVA and total organic carbon levels. Catalysts show high activity at 180 deg.C and carbon adsorption is not observed; Mn-Ce-O shows significant leaching to the liquid-phase compared with CuO-ZnO/Al 2O3. Acetic and formic acids are detected as refractory compounds for oxidation. 24 refs. Coimbra University; Ljubljana University EUROPEAN COMMUNITY; EUROPEAN UNION; PORTUGAL; SLOVENIA; WESTERN EUROPE

Accession no. 915304 Item 274 Macplas International May, 2004, p.21 DEGRADABLE FILMS - THE ADEPT POLYVINYL ALCOHOL BINDING TAPE Katco and Environmental Polymers are reported in this concise article to have jointly developed a polyvinyl alcohol binding tape for thermal moulding in the automotive sector. Brief details of the new tape which is known as Adept are given here.

89


Katco; Environmental Polymers EUROPE-GENERAL

Accession no. 914709 Item 275 Polymer 45, No.12, 2004, p.4037 EFFECT OF SYNDIOTACTICITY ON THE MORPHOLOGY OF WATERSOLUBLE LOW MOLECULAR WEIGHT POLY(VINYL ALCOHOL) BY SOLUTION COPOLYMERIZATION OF VINYL PIVALATE/ VINYL ACETATE IN TETRAHYDROFURAN AND SAPONIFICATION Yeum J H; Ji B C; Noh S K; Jeon H Y; Kwak J W; Lyoo W S The synthesis of low molecular weight poly(vinyl alcohol) (PVA) by solution copolymerisation of vinyl pivalate and vinyl acetate in various monomer ratios using 2,2'-azobis(2,4-dimethylvaleronitrile) as initiator with subsequent hydrolysis of the copolymer is described. The resulting PVA was characterised by molecular weight (viscosity) proton NMR (syndiotacticity) surface morphology (optical microscopy) and solubility and the results are discussed. 16 refs. Kyungpook National University; Yeungnam University; Chonnam National University

Badr Y A; El-Kader K M A; Khafagy R M The preparation of composite films of poly(vinyl alcohol) with the semi-conducting material cadmium sulphide in varying proportions and their characterisation by FTRaman spectroscopy UV-visible-IR spectroscopy x-ray diffraction and current-voltage characteristics is described. The results are interpreted in terms of the formation of new bonds and the potential application of the material to the production of solar cells is discussed. 52 refs. Cairo University; Suez Canal University; Cairo Ain Shams University EGYPT

Accession no. 914026 Item 278 Polymers and Polymer Composites 12, No.3, 2004, p.235 A ZONE DRAWING METHOD TO DETERMINE OPTIMUM INITIAL CONCENTRATION OF POLY(VINYL ALCOHOL) TO MAKE FILMS WITH DIFFERENT DEGREES OF SAPONIFICATION Joon Ho Kim; Won Sik Yoon; Jeong Hyun Yeum; Byung Chul Ji; Hee Sam Kim; Han-Yong Jeon; Won Seok Lyoo

EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE

The optimum preparation conditions for atactic polyvinyl alcohol films were investigated by measuring the polymer concentration draw ratio and degree of saponification. Atactic PVA films were prepared by casting in water with different polymer concentrations. The a-PVA films were zone-drawn under various conditions. Using the optimum polymer concentration of the a-PVA/water solutions caused significant changes in the draw ratio of the films which were maximised at the initial polymer concentration but which gradually decreased at higher or lower concentrations. The birefringence degree of crystal orientation and tensile properties of a-PVA films having the same draw ratios were the highest at these optimum polymer concentrations. Optimum concentrations were reconfirmed by viscometry. Optimum conditions of the film casting of atactic PVA with various degrees of saponification were established by the zone drawing method. The agreement between the optimum concentration values obtained by zone drawing and viscometry suggests that the zone drawing method is an appropriate and convenient way to establish the optimum concentration for maximum draw ration birefringence degree of crystal orientation and tensile properties. 18 refs. Yeungnam University; Kyungpook National University; Chonnam National University


KOREA

SOUTH KOREA

Accession no. 914518 Item 276 Plastics and Rubber Weekly 2004, p.1 STANELCO BANKS ON ECO BUBBLE WRAP Cundy C Stanelco is poised to make commercial breakthroughs with an environmentally friendly bubble wrap and a completely water-soluble adhesive tape. The water-soluble and biodegradable bubble wrap material is a 50:50 mix of starch and PVOH. It is said to be close in cost to conventional plastics less abrasive and holds air in the bubbles for longer. Stanelco is presently filing patents for its new adhesive tape that is claimed to be 100% watersoluble and leaves no residue. It uses a PVOH film and a soluble adhesive which subsidiary Adept Polymers has spent seven years developing. Stanelco Products Ltd.

Accession no. 913441 Item 277 Journal of Applied Polymer Science 92, No.3, 2004, p.1984 RAMAN SPECTROSCOPIC STUDY OF CDS PVA COMPOSITE FILMS

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Item 279 ACS Polymeric Materials: Science and Engineering, Spring Meeting 88, 2003, p.414



STUDY ON STABILITY CU NANOPARTICLE IN PVA NANOFIBER Wang C; Li Z; Yang Q; Hong Y

Chungnam National University; Kyung Hee University; Seoul National University

Hybrid materials were prepared from PVAl nanofibre and copper nanoparticles in the presence of sodium bisulphite deoxidant by electrospinning and the stability of the copper nanoparticles in the nanofibre investigated under a high voltage. It was found that the structure and properties of the nanoparticles were not affected by the high voltage and their stability in air was greatly increased. 1 ref


CHINA

Accession no. 912160 Item 280 Polymer 45, No.6, 2004, p.1895 FABRICATION OF BLEND BIODEGRADABLE NANOFIBROUS NONWOVEN MATS VIA MULTIJET ELECTROSPINNING Ding B; Kimura E; Sato T; Fujita S; Shiratori S A series of blend biodegradable nanofibrous mats comprising poly(vinyl alcohol) (PVA) and cellulose acetate (CA) were prepared via multi-jet electrospinning using a relatively high voltage supply (20 kV). The weight ratio of PVA/CA in blend nanofibrous mats was controlled by changing the number of jets for each polymer solution. The composition of PVA and CA in the mats was determined by immersing them in water to remove the PVA component and measuring the weight loss. Morphology dispersibility and mechanical properties of the mats were examined by field emission scanning electron microscopy (FE-SEM) FTIR spectroscopy wide-angle X-ray diffraction (WAXD) and tensile testing. The blend nanofibrous mats have good dispersibility and uniform properties for each sample. Their mechanical properties were largely influenced by the weight ratio of PVA/CA in the blends. 26 refs. Yokohama Keio University; Shiratori Nanotechnology Co.Ltd. JAPAN

Accession no. 910844 Item 281 Journal of Materials Science. Materials in Medicine 15, No.3, 2004, p.297 EFFECTS OF PVA SPONGE CONTAINING CHITOOLIGOSACCHARIDE IN THE EARLY STAGE OF WOUND HEALING You Y; Park W H; Ko B M; Min B-M Details are given of the preparation of PVAL sponges with different chitooligosaccharide content for wound-dressing applications. Morphologies were examined using SEM. The accelerating effect of the chitooligosaccharide-loaded PVAL sponge on open wound healing was investigated by macroscopic examination and measurement of wound area. 12 refs.


KOREA

Item 282 Journal of Polymer Science: Polymer Physics Edition 42, No.5, 2004, p.800 VISCOELASTIC BEHAVIORS AND MOLECULAR MOTIONS OF HIGHLY SYNDIOTACTIC POLY(VINYL ALCOHOL) FIBERS Gotoh Y; Nagara Y; Nakano T; Okamoto Y; Ohkoshi Y; Nagura M The viscoelastic behaviour and molecular motion of highly syndiotactic poly(vinyl alcohol) (PVA) fibres were investigated by dynamic mechanical thermal analysis and wide-angle x-ray diffraction in comparison with those for atactic PVA fibres. The results are discussed in terms of differences in intermolecular hydrogen bonding leading to the formation of hydrogels with high water resistance and large modulus from syndiotactic PVA without chemical crosslinking. 40 refs. Shinshu University; Nagoya University; Nara Institute of Science & Technology JAPAN

Accession no. 910263 Item 283 International Polymer Science and Technology 30, No.8, 2003, p.T/47-50 BLENDS BASED ON POLYVINYL ALCOHOL AND POLYHYDROXYBUTYRATE Ol'khov A A; Iordanskii A L; Shatalova O V This work reports on the use of blending techniques to modify the properties of materials based on polyvinyl alcohol (PVA). The structural features and properties were investigated of composites based on PVA and polyhydroxybutyrate by different methods of structural analysis. The composite blend was obtained by melt extrusion. The structure of the films was studied by differential scanning calorimetry the tensile properties of the film specimens were also tested and steam permeability was studied using special membrane cells by measuring the weight loss by the cell. Results of X-ray diffraction analysis indicate that each of the components of the blend is capable of forming an independent crystalline phase. Details are given of optimum blend ratios. 15 refs. (Article translated from Plasticheskie Massy No. 12 2002 pp.20-2). Lomonosov M.V.Academy of Fine Chemical Technology; Russian Academy of Sciences RUSSIA


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Item 284 Polymer 45, No.5, 2004, p.1599 OXYGEN BARRIER PROPERTIES OF BIAXIALLY ORIENTED POLYPROPYLENE/ POLYVINYL ALCOHOL BLEND FILMS Jang J; Lee D K A biaxially oriented polypropylene/poly(vinyl alcohol) (PP/PVA) blend film was prepared that had an oxygenbarrier property that was about 130 times that of biaxially oriented PP (BOPP) film. When the PVA-PP viscosity ratio decreased the dispersed PVA phase developed into platelets during the stretching process. The oxygen permeability depended on the number and size of the PVA platelets. Optimal amounts of plasticiser and initiator were required to give the best barrier properties. An initiator played the role of a compatibiliser. The oxygen barrier was enhanced by increasing the viscosity of the PP and the draw ratio. A higher viscosity of PP was advantageous for preventing delamination of the blend film and the moisture vapour permeability was unaffected by the laminar structure. Biaxially oriented PP/PVA blend film is a potential substitute for PVDC-coated BOPP film. 18 refs. Seoul National University SOUTH KOREA

Accession no. 908133 Item 285 Journal of Applied Polymer Science 91, No.3, 2004, p.1612 PREPARATION AND CHARACTERIZATION BY RADIATION OF HYDROGELS OF PVA AND PVP CONTAINING ALOE VERA K R Park; Y C Nho Gelation gel strength water absorption and degree of water evaporation from hydrogels prepared from a blend of polyvinyl alcohol and polyvinyl pyridine mixed with Aloe vera were examined to determine the relative value of the various materials for use in wound dressings. Polymerisation methods for the hydrogels included freezethaw gamma-ray irradiation or a two-step combination of these. Gel content and strength was inversely affected by increasing amounts of Aloe vera and increasing radiation dose. Degree of swelling reduced with increasing gel strength and content. Wound healing properties were evaluated and found to be improved compared to commercial products. 10 refs. Korea Atomic Energy Research Institute KOREA

Accession no. 907415 Item 286 Paint and Coatings Industry 20, No.3, 2004, p.70/7

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PHOTOCURING OF WATERBORNE LATEX PAINTS UNDER SUN AND VISIBLE-LIGHT SOURCES Burget D; Bibaut-Renauld C; Fouassier J P; Varelas C G; Charalambopoulou G Ch; Ryrfors L O; Karlsson O J By using alpha-diketones and especially camphorquinone white pigmented waterborne latex formulations based on acrylates or vinyl acetate for outdoor/indoor paints can be cured under visible light including sunlight. The cured paint showed an excellent solvent resistance towards THF and the light-cured paints exhibit a hardness up to 30% higher than comparable VOC-containing paints. The lightcurable paints can be produced by simply replacing the VOC by a photocurable composition which will simplify their industrial acceptance. 3 refs. Mulhouse Ecole Nationale Superieure de Chimie; Interchem Hellas SA; Celanese Emulsions Norden AB EUROPEAN COMMUNITY; EUROPEAN UNION; FRANCE; GREECE; SCANDINAVIA; SWEDEN; WESTERN EUROPE

Accession no. 907154 Item 287 Air Products Polymers LP, 2003 WET ADHESION MONOMER AND DERIVED COPOLYMERS FOR LATEX PAINTS Pinschmidt J R K; Yacoub K; Daniels C L; Phung K V The reaction of unsaturated carbonates such as vinyl ethylene carbonate with N-aminoethylimidazolidone (TAM) under mild conditions generates a mixture of two vinyl and hydroxy functional imidazolidone carbamates which polymerise readily to acrylate or vinyl acetate based emulsion polymers. The polymers show enhanced wet adhesion (wet scrubbability) in latex paints and coatings. USA

Accession no. 906259 Item 288 Polymer Testing 23, No.1, 2004, p.17 PREPARATION SURFACE MODIFICATION AND CHARACTERISATION OF SOLUTION CAST STARCH PVA BLENDED FILMS Jayasekara R; Harding I; Bowater I; Christie G B Y; Lonergan G T Details are given of the preparation of PVAL starch and glycerol blends. The blend containing 20% PVAL was modified by the application of chitosan to the surface. The blend and its modified form were characterised by atomic force microscopy X-ray diffraction FTIR contact angle measurements carbon-13C-NMR and SEM. 23 refs. Swinburne University of Technology AUSTRALIA




Item 289 Polymer 44, No.26, 2003, p.8139 PLASTICIZER EFFECT ON THE MELTING AND CRYSTALLIZATION BEHAVIOR OF POLYVINYL ALCOHOL Jyongsik Jang; Dong Kweon Lee The effect on melting and crystallisation behaviour of the addition of glycerol as a plasticiser to four different grades of polyvinyl alcohol (PVA) was studied using differential scanning calorimetry. PVA samples were either fully or partially hydrolysed and of different viscosities. At higher hydrolysis levels crystallisation peak temperature was reduced crystallisation rate slowed and crystallite size distribution widened with plasticiser addition but effects on crystallisation behaviour of partially hydrolysed PVA were minimal. In contrast the thermal history was seen to affect partially hydrolysed materials but not the fully hydrolysed samples. Melting point reduction with increasing plasticiser levels was observed in all cases. Effects of plasticiser addition were much reduced when phase separation occurred between glycerol and PVA. Blend systems of fully and partially hydrolysed PVA polymers were also examined and were seen to have twin melting temperatures and concurrent crystallisation. 20 refs. Seoul National University SOUTH KOREA

Accession no. 905465 Item 290 Chemical Engineering Research and Design 81, No.A10, 2003, p.1385 EFFECTS OF DEGREE OF FORMALDEHYDE ACETAL TREATMENT AND MALEIC ACID CROSSLINKING ON SOLUBILITY AND DIFFUSIVITY OF WATER IN PVA MEMBRANES Han B; Li J; Chen C; Xu C; Wickramasinghe S R The sorption desorption and solubility of water vapour and liquid in poly(vinyl alcohol) (PVA) membranes treated by formaldehyde were compared with those for PVA membranes with various degrees of maleic acid crosslinking and the results discussed in terms of the effects of structural differences on the diffusivity and solubility of water molecules. Experimental results are considered in terms of the common pervaporation models. 28 refs. Tsing Hua University; Colorado State University CHINA; USA

Accession no. 904677 Item 291 Journal of Applied Polymer Science 90, No.14, 2003, p.3912 EFFECT OF MEMBRANE MORPHOLOGY IN PERVAPORATIVE SEPARATION OF ISOPROPYL ALCOHOL-AROMATIC


MIXTURES: A THERMODYNAMIC APPROACH TO MEMBRANE SELECTION Mandal S; Pangarkar VP The separation of isopropyl alcohol (IPA)-benzene and IPA-toluene azeotropic mixtures by pervaporation through several polymeric hydrophilic membranes of various solubility parameters such as regenerated cellulose poly(vinyl alcohol) (PVA) cellulose acetate (CA) cellulose diacetate (CDA) and cellulose triacetate (CTA) was studied over the entire composition range at 30 deg C. Some of these membranes gave a gradual shift in the azeotropic point which depended on the solubility parameter and the solute-polymer interaction parameter. Regenerated cellulose film gave the best pervaporation performance in terms of selectivity to IPA and durability. PVA showed a high selectivity with a reasonable flux. Poly(dimethylsiloxane) was also studied as an aromatic selective membrane. 41 refs. Mumbai University INDIA

Accession no. 904587 Item 292 Journal of Applied Polymer Science 90, No.14, 2003, p.3848 INFLUENCES OF INDIVIDUAL AND COMPOSED POLY(VINYL ALCOHOL) SUSPENDING AGENTS ON PARTICLE MORPHOLOGY OF SUSPENSION POLY(VINYL CHLORIDE) RESIN Yong-Zhong Bao; Jian-Gang Liao; Zhi-Ming Huang; Zhi-Xue Weng Effects of individual and composite poly(vinyl alcohol) (PVA) suspending agents on the particle morphology of poly(vinyl chloride) (PVC) resins were investigated and discussed in relation to PVA absorption at the oil/ water interface and interfacial behaviour. The percentage and surface coverage of PVA at the oil/water interface decreased with increasing degree of hydrolysis (DH) of PVA in the DH range 70-98 mol % whereas the interfacial tension of VC/PVA aqueous solution increased linearly with increasing DH of the PVA. PVC resin with moreregular particle shape increased agglomeration and fusion of primary particles lower porosity and higher bulk density was prepared by using PVA with a higher DH as a suspending agent. This was caused by drop coalescence at the very early stages of VC polymerisation an increase in particle shrinkage and a lower colloidal protection to primary particles. The interfacial tension of VC/water varied linearly with the weight composition of the composite PVA suspending agents. The particle properties of PVC resin prepared by using the composite PVC suspending agents were usually intermediate between the properties of PVC resins prepared by using the corresponding individual PVA suspending agent. The particle morphology and properties of PVC resin could be controlled by a suitable choice of the composite PVA

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suspending agents. 21 refs. Zhejiang University CHINA

Accession no. 904579 Item 293 Synthetic Metals 135-6, 2003, p.447 ELECTRICAL PROPERTIES OF PVA/PPY BLENDS de Oliveira H P; dos Santos M N B; dos Santos C G; de Melo C P A dielectric study of polymeric blends composed by polypyrrole (PPY) incorporated into a matrix a polyvinyl alcohol (PVA) containing ferric chloride (FeCl3) is presented. The PPY conducting regions are formed inside the matrix by in situ polymerisation after the (PVA+FeCl3) matrix is exposed to the vapour of the monomer. The mixed dielectric/conducting characteristics of the resulting blend are conveniently characterised by dielectric spectroscopy and in this manner both the charge transport and charge storing processes can be followed. The ways in which the temperature variation in the 300-24 K range affects the electrical behaviour of the material are also examined. 4 refs. Pernambuco Universidade Federal BRAZIL

Accession no. 904082 Item 294 Macromolecular Rapid Communications 24, No.12, 2003, p.715 POLY(VINYL ALCOHOL)-ENCAPSULATED HYDROPHILIC CARBON BLACK NANOPARTICLES FREE FROM AGGREGATION Li H-Y; Chen H-Z; Sun J-Z; Cao J; Yang Z-L; Wang M Carbon black (CB) nanoparticles are encapsulated by polyvinyl alcohol (PVA) by a simple method of coacervation. Transmission electron microscopy (TEM) images clearly demonstrate that the successful encapsulation of PVA happens at the surfaces of CB nanoparticles. Particle size distribution measurements indicate that the diameters of the obtained PVAencapsulated CB (CB at PVA) nanoparticles are distributed within the nanoscale dimension. This strategy avoids the complicated polymerisation process involved in the counterpart of polymer-coating approaches. 7 refs. Accession no. 903875 Item 295 Journal of Applied Polymer Science 89, No.5, 2003, 890 ELECTROACTIVE CHARACTERISTICS OF INTERPENETRATING POLYMER NETWORK HYDROGELS COMPOSED OF POLY(VINYL

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ALCOHOL) AND POLY (N-ISOPROPYLACRYLAMIDE) Seon Jeong Kim; Sang Jun Park; Sang Min Lee; Young Moo Lee; Hee Chan Kim; Sun I Kim An interpenetrating polymer network (IPN) composed of poly(vinyl alcohol) (PVA) and poly(N-isopropylacrylamide) (PNIPAAm) was prepared by the sequential IPN method. The equilibrium swelling ratio and bending behaviour under an electric fields were measured in aqueous NaCl. The IPN exhibited a high equilibrium swelling ratio in the range 280-380%. When the IPN in aqueous NaCl solution was subjected to an electric field the IPN showed significant and rapid bending toward the cathode. The IPN hydrogel also showed stepwise bending behaviour depending on the electric stimulus. In addition the ionic conductivity of the IPN hydrogel was measured using dielectric analysis and its conductive behaviour followed the Arrhenius equation. The conductivity of the IPN hydrogel and the activation energy for the form of the IPN were 0.0000168 S/cm at 36C and 61.0 kJ/mol respectively. 22 refs. Hanyang University; Seoul National University KOREA

Accession no. 903720 Item 296 Journal of Polymer Science: Polymer Physics Edition 41, No.23, 2003, p.3127 INFLUENCE OF THE SURFACE CHEMISTRY ON THE STRUCTURAL AND MECHANICAL PROPERTIES OF SILICA-POLYMER COMPOSITES Boisvert J-P; Persello J; Guyard A Composite films of poly(vinyl alcohol) (PVA) filled with nanometric monodisperse or spherical silica particles were prepared by the mixing an aqueous PVA solution with a colloidal suspension of silica and then evaporating the solvent. The interaction between the PVA and the silica was controlled by adjusting the solution pH to 5 or 9. Adsorption isotherms showed a higher PVA/surface affinity at the lower pH. This interaction affected the structure of the composite and the particle distribution within the polymer matrix: this was investigated by smallangle neutron scattering electron microscopy and swelling measurements. Most of the mechanical properties could be related to the distribution of clusters within the polymer matrix. The progressive creation of a cluster network within the polymeric matrix with increasing silica volume fraction reduced the extensibility or swelling capacity of the composite. The effect was more acute at a higher pH where the surface interaction with PVA was weaker and promoted interconnection of clusters. refs. QUEBEC UNIVERSITE A TROIS-RIVIERES; FRANCHE-COMTE UNIVERSITE CANADA; EUROPEAN COMMUNITY; EUROPEAN UNION; FRANCE; WESTERN EUROPE




Item 297 Journal of Applied Polymer Science 84, No.6, 2002, p.1295 CUT-OUT FILTER FOR ULTRAVIOLET RADIATION FROM POLY(VINYL ALCOHOL) Abd El-Kader K M; El-Lawindy Y M; Mansour A F; Abdel Hamied S F The effects of UV radiation and thermal annealing on the optical and mechanical properties of polyvinyl alcohol (PVA) were studied. Pure PVA samples were prepared by casting and a xenon arc lamp used to irradiate the sample. The irradiated PVA sample was heated at 150C for 2 hours. The optical and mechanical properties of original irradiated and irradiated and then heated samples were measured. The irradiated and then heated sample showed lower transmission in the wavelength range from 190 to 320 nm and the transmission was higher in the visible region than the original and irradiated samples. Stressstrain measurements were performed. The modulus of elasticity of the double-treated sample was approximately four times higher than that of the original sample and the results showed that this sample could be used as a cut-out filter for UV radiation. 21 refs. Suez Canal University; Zagazig University EGYPT

Accession no. 901879 Item 298 Polymer Preprints. 2003, 44, No.1, p.402 WHEAT PROTEIN AND ITS POLYMER BLENDS STUDIED BY SOLID-STATE HIGHRESOLUTION NMR SPECTROSCOPY Xiaoqing Zhang; Burgar I; My Dieu Do; Lourbakos E; Beh H High resolution nuclear magnetic resonance spectroscopy was used to investigate the chemical structures intermolecular interactions and molecular motions concerned with the miscibility of blends of wheat protein and polyvinyl alcohol (PVOH) with between 0 and 25 percent PVOH content. Both solution casting and thermal processing methods were used to prepare blends of PVOH and wheat protein plasticised using glycerol and water. Semi miscible blends were formed using solution casting methods when PVOH content was less than 20 percent but thermally processed blends showed greater heterogeneity. Examination on the nanometre scale also indicated heterogeneity. 8 refs. AUSTRALIA

Accession no. 901105 Item 299 Polymer Bulletin 50, No.5-6, 2003, p.367


WATER-SOLUBLE TEMPERATURERESPONSIVE POLY(VINYL ALCOHOL-COVINYL ACETAL)S Christova D; Ivanova S; Ivanova G In order to obtain novel polyvinyl alcohol (PVA) is chemically modified by introducing cyclic acetal functionalities in the polymer chain. The acetalisation reaction is carried out with acetaldehyde in water. The degree of acetalisation is controlled in the range 10-25% by the initial aldehyde concentration. The copolymers obtained are characterised by 1D (1H 13C DEPT) and 2D (COSY) NMR techniques as well as by viscometry. The thermo-responsive properties are evaluated by measuring the cloud point temperature (Tcp) of the aqueous copolymer solutions. 15 refs. Bulgarian Academy of Sciences BULGARIA; EASTERN EUROPE

Accession no. 901098 Item 300 Flexible 2, No.4, 2003, p.16 EXPLOSIVE PLASTICS Anyadike N Ethylene vinyl alcohol (EVOH) and polyvinyl alcohol (PVOH) are the two main water-soluble polymer types commercially available. Films cast from water solutions of PVOH and plasticiser are transparent tough tear- and puncture-resistant. Such films are used for hospital laundry bags that can be loaded directly into the washing machine without the need for contents handling. EVOH acts by completely blocking the permeable barrier unlike many other traditional plastic materials which allow oxygen ingress. It is able to extend the shelf life of food items with EVOH copolymers characterised by their outstanding gas barrier properties resistance to solvents chemicals and hydrocarbons and excellent barrier to odour and flavour permeance. Nippon Gohsei is constructing a new EVOH facility in the UK. The 15000 t/y plant which will produce Soarnol is expected to be fully operational in early 2004. EVAL Europe has also undertaken steps to expand production capacity at its site at the Antwerp Chemical complex from 12000 to 24000 t/y. WORLD

Accession no. 900984 Item 301 Journal of Materials Science Letters 22, No.18, 2003, p.1291 EFFECT OF DEGREE OF POLYMERIZATION ON SYNTHESIS OF ANORTHITE-TYPE POWDER BY WET-CHEMICAL METHOD EMPLOYING PVA Lee S J; Lee M H

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Anorthite powder was synthesised from calcium nitrate aluminium nitrate and silica sol by the PVAl steric entrapment route. The effects of the degree of polymerisation and content of PVAl on the crystallisation behaviour specific surface area particle size distribution and primary crystalline size of the powder were examined. Both polyvinyl alcohol content and degree of polymerisation were found to have a marked influence on the synthesis and properties of the powder. 14 refs. Mokpo National University; Korea Institute of Ceramic Engineering & Technology KOREA


in the range 0.4-1.2wt% and the solid concentration of the PVA/PVP/Aloe vera solution was 15wt%. Mixtures of PVA/PVP/Aloe vera were exposed to gamma radiation doses of 25 35 and 50 kGy to evaluate the effect of radiation dose on the physical properties of the hydrogels. Gel content and gel strength increased as the concentration of Aloe vera in the PVA/PVP/Aloe vera gels decreased and as radiation dose increased and the number of freeze thaw cycles was increased. The swelling degree was inversely proportional to the gel content and gel strength. The PVA/ PVP/Aloe vera hydrogel had a better curing effect than no dressing an a commercial urethane membrane. 13 refs. Korea Atomic Energy Research Institute KOREA

Item 302 International Journal of Polymer Analysis and Characterization 8, No.5, 2003, p.339 SYNTHESIS CHARACTERIZATION AND SOLUTION PROPERTIES OF ACRYLIC ESTER POLYMERS Mathakiya I; Rakshit A K; Rao P V C Homopolymers of vinyl acetate and various acrylates and copolymers thereof were synthesised by free-radical solution polymerisation and copolymerisation and characterised by FTIR spectroscopy NMR spectroscopy TGA GPC and viscosity measurements. Reactivity ratios of monomers in the vinyl acetate-acrylate copolymers were computed from NMR spectroscopic data using the Fineman-Ross and Kelen-Tudos methods. The voluminosity shape factor activation parameters of viscous flow root-mean-square end-to-end distance radius of diffusing particle and diffusion coefficients were also computed at various temperatures to establish the solution properties of the polymers and copolymers. 31 refs. Baroda MS University; Indian Petrochemical Corp.Ltd. INDIA

Accession no. 899907 Item 303 Journal of Applied Polymer Science 90, No.6, 2003, p.1477 PREPARATION AND CHARACTERIZATION BY RADIATION OF POLY(VINYL ALCOHOL) AND POLY(N-VINYLPYRROLIDONE) HYDROGELS CONTAINING ALOE VERA Kyoung Ran Park; Young Chang Nho Hydrogels for wound dressings were made from a mixture of Aloe vera and poly(vinyl alcohol) (PVA)/poly(Nvinylpyrrolidone) (PVP) by freezing and thawing gammaray irradiation or a two-step process of freezing and thawing and gamma-ray irradiation. Physical properties were measured including gelation water absorptivity gel strength and degree of water evaporation to evaluate the applicability of these hydrogels for wound dressings. The PVA:PVP ratio was 6:4 the dry weight of Aloe vera was

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Accession no. 899622 Item 304 Journal of Applied Polymer Science 90, No.6, 2003, p.1471 WATER TRANSPORT STRUCTURE FEATURES AND MECHANICAL BEHAVIOR OF BIODEGRADABLE PHB/PVA BLENDS Olkhov A A; Vlasov S V; Iordanskii A L; Zaikov G E; Lobo V M M\ Blends of biodegradable poly(3-hydroxybutyrate) (PHB) with biocompatible and water-soluble poly(vinyl alcohol) (PVA) were prepared by extrusion. The structure of the blends was studied by wide angle X-ray diffraction and DSC. Water vapour permeation and tensile properties of the blends were measured. The materials appeared to be partially miscible up to PHB contents of between 20-30% by weight above which a phase inversion takes place and mechanical properties drop to values characteristic of pure PHB. Water permeability goes through a maximum at PHB contents around 40% by weight. These materials are of interest as novel biodegradable films and coatings for biomedical agricultural and packaging applications. 22 refs. Moscow Institute Of Chemical Physics; Coimbra University RUSSIA

Accession no. 899621 Item 305 Macromolecular Symposia No.197, 2003, p.143 CHARACTERISTICS AND DEGRADATION OF HYBRID COMPOSITE FILMS PREPARED FROM PVA STARCH AND LIGNOCELLULOSICS Cinelli P; Chiellini E; Gordon S H; Imam S H Details are given of the preparation of cast films by blending orange fibres and PVAL with and without corn starch. Films were also prepared by crosslinking PVAL starch and orange fibres with hexamethoxymethylmelamine. Films were evaluated for their thermal stability water permeability and biodegradation. A possible stimulating



effect of lignocelluloses fillers on the biodegradation of PVAL in blends was observed. 21 refs. Pisa University; US Dept. of Agriculture EUROPEAN COMMUNITY; EUROPEAN UNION; ITALY; USA; WESTERN EUROPE

Accession no. 897890 Item 306 EP 1347107 A1 20030924 POLYVALENT INSULATING ANTI-VIBRATORY ADHESIVE AND FIREPROOF PRODUCT FOR VARIOUS INDUSTRIAL SECTORS ESPECIALLY THE BUILDING INDUSTRY Bonacini V The product is suitable for use in cladding facades weatherproofing for roofing thermal and/or acoustic insulation preventing damp and efflorescence of salts absorbing vibration encapsulating elements protecting structures and elements against fire as a means of coating backings for making carpets preventing filtration elasticising and binding loose carrier materials lining gutters conduits and piping adhesives for solid materials and expansion joints. It comprises 10 to 49% acrylic resin 20 to 28% polyvinyl acetate 1 to 8% vegetable 10 to 20% water 0 to 12% cork particles 1 to 4% sodium hydroxide 0 to 58% pigment and 0 to 5 % cellulose glue. EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE; WESTERN EUROPEGENERAL Accession no. 897360 Item 307 Polymer Degradation and Stability 81, No.3, 2003, p.393 NUMERICAL SIMULATION FOR ENZYMATIC DEGRADATION OF POLY(VINYL ALCOHOL) Watanabe M; Kawai F The enzymatic degradation of polymeric compounds is studied. A mathematical model is proposed that governs the temporal change of the weight distribution with respect to the molecular weight. A particular case is investigated in which the molecules are degraded randomly and a technique to solve the inverse problem to determine the degradation rate numerically is developed. The technique is illustrated with an example in which GPC profiles of polyvinyl alcohol are introduced into the numerical computation. PVA is degraded by random oxidation of hydroxyl groups and following cleavage of carbon-carbon chain between two carbonyl groups/a carbonyl group and an adjacent hydroxymethine group either by hydrolase or aldolase. 10 refs. Okayama University JAPAN



Item 308 International Journal of Polymeric Materials 52, No.7, 2003, p.623 EFFECT OF CHEMICAL CROSSLINKING ON SWELLING PARAMETERS OF MODIFIED POLY(VINYL ALCOHOL) HYDROGEL Atta A M; El-Ghazawy R A M Graft copolymerisation of maleic anhydride (MA) onto partially and fully hydrolysed polyvinyl alcohol PVA is carried out in presence and in absence of an initiator. The structural features of these grafts are confirmed by 1H-NMR analysis. 1H-NMR analysis is also used to determine the percentage of grafting. These grafts are crosslinked using different concentrations of either 111-trimethylolpropane trimethacrylate (TPT) or methylene bisacrylamide (MBA) as hexa- or tetra-functional crosslinker respectively. The crosslinkers concentrations range from 1 to 30% (wt.%) based on the total weight of grafts. The final water content volume fraction of the polymer and swelling capacity are determined for all grafts. The effect of MBA and TPT crosslinkers structure on swelling properties of both partially and fully hydrolysed PVA grafts are also determined. 30 refs. Egyptian Petroleum Research Institute EGYPT

Accession no. 896962 Item 309 ACS Polymeric Materials: Science and Engineering, Fall Meeting 87, 2002, p.502 POLYMER PARTICLES STABILIZED IN THE PRESENCE OF POLY VINYL ALCOHOL Zecha H The effect of grafted or adsorbed surface layers of polyvinyl alcohol (PVOH) on the stability of polymer latices is investigated and the results are briefly described. An equation is presented to calculate delta the hydrodynamic effective thickness of the PVOH layer in dilute latices from the viscosity total particle volume fraction adsorbed/grafted PVOH fraction and PVOH volume fraction with respect to the particles. The equation was in good accordance with empirical results. Delta was shown to increase with the molecular weight of PVOH. Delta was also observed to be greater in styrene-acrylic copolymer latices than in polyvinyl acetate (PVAC) latices. It is reported that in more concentrated latices the assumption that that the fraction of adsorbed/grafted PVOH is independent of the latex concentration is untrue and that in PVAC latices the PVOH fraction is strongly dependent on the latex concentration. It is argued that all of these results imply that the stabilisation of latices by PVOH is not simply a steric effect and that the concentration dependence of latex viscosity cannot be described solely on the basis of effective hydrodynamic volume fraction. 14 refs.

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EUROPEAN COMMUNITY; EUROPEAN UNION; GERMANY; WESTERN EUROPE


Item 312 JIS K6808. POLYVINYL ACETATE EMULSION ADHESIVES FOR WOODS Version 94 (R2001). Japanese Standards Association

Item 310 International Polymer Science and Technology 30, No.6, 2003, p.T/44 INFLUENCE OF TEMPERATURE EFFECTS ON THE STRUCTURE AND PHYSICOMECHANICAL PROPERTIES OF FILLED GELS OF POLYVINYL ALCOHOL Ukhartseva I Y An investigation is reported that shows that filled PVA gels formed under different production conditions can be used as the basis for creating materials with controllable properties. Such materials can be applied to drug-containing therapeutic systems that are capable of controlled release of the medicine into the surrounding medium. The influence is examined of the schedules for forming filled PVA gels on their structure and physicomechanical characteristics. The investigation was carried out on PVA medical gelatin proteolytic enzyme papain medical collagen and sodium salt of carboxymethyl cellulose. Films were obtained from the composites by casting and were formed at a temperature of 293 K and under low-temperature conditions at a temperature of 267 K for 24 hours. Specimens prepared in this way were used to study physicomechanical characteristics and to determine structural parameters. 21 refs. (Article translated from Plasticheskie Massy No.8 2002 pp.15-7). Belarus Academy of Sciences BELARUS; BELORUSSIA

Accession no. 896786 Item 311 Polymer 44, No.15, 2003, p.4075 EFFECTS OF CONONSOLVENCY ON GELATION OF POLY(VINYL ALCOHOL) IN MIXED SOLVENTS OF DIMETHYL SULFOXIDE AND WATER Takahashi N; Kanaya T; Nishida K; Kaji K The rates of gelation and phase separation of polyvinyl alcohol (PVA) solutions in mixtures of dimethyl sulphoxide (DMSO) and water at 25 deg.C are studied and it is found that both the rates show a maximum at a volume fraction of DMSO thetaDMSO = 0.60 while gelation is not observed either in pure DMSO or pure water suggesting that water-DMSO is a cononsolvent system for PVA. On the basis of the data by Cowie it is concluded that the 1:2 stable complex between one DMSO molecule and two water molecules is the main cause of this cononsolvency. 19 refs. Kyoto University JAPAN


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JAPAN

Accession no. 895201 Item 313 JIS K6725. TESTING METHOD FOR POLYVINYL ACETATE Version 77(R2002). Japanese Standards Association Photocopies and loans of this document are not available from Rapra. JAPAN

Accession no. 895190 Item 314 Iranian Journal of Polymer Science and Technology 16, No.1, 2003, p.13 STUDY OF THE EFFECT OF ACETIC ACID AND POLYETHYLENE GLYCOL ON MORPHOLOGY AND PERFORMANCE OF POLYVINYL ALCOHOL MEMBRANE Madaeni S S; Semsarzadeh M A; Moghaddasi S P; Nomani H The effects of acetic acid and polyethylene glycol (PEG) on morphology and characteristics studies of polyvinyl alcohol (PVA) membrane are investigated. The membranes are prepared using phase inversion technique. For membrane manufacture a dope containing PVA water and either acetic acid or PEG is prepared. The dope is moulded by casting and floated in a precipitation bath containing Na2SO4/NaOH/H2O. The results show that addition of acetic acid or PEG to PVA will change the mechanism of membrane preparation leading to changes in the membrane's morphology and characteristics. Increasing the acetic acid concentration results in reduction in skin layer thickness and increase of its sub-layer thickness porosity and pore size. Reduction in skin layer thickness and porosity results in higher permeability and better membrane performance. This may be explained due to the higher concentration of H3O+ in polymer dope resulting from an increase in acetic acid concentration. Higher concentrations of positive ions facilitate the nonsolvent entrance from precipitation bath to polymer dope resulting in a higher rate for acid-base equilibrium. PEG is a polar and hydrophilic polymer which performs as an electrolyte in polymer solution. Higher concentration of PEG results in a higher rate of non-solvent entrance from precipitation bath to polymer dope. In comparison with acetic acid PEG shows lower effect on membrane performance (permeability) reduction of skin layer thickness and increase in sub-layer thickness. Razi University; Tarbiat Modarres University; Kermanshah University of Medical Sciences



IRAN

Accession no. 895024 Item 315 Iranian Polymer Journal 12, No.2, 2003, p.139 POLY(VINYL ALCOHOL)-CHITOSAN BLENDS: PREPARATION MECHANICAL AND PHYSICAL PROPERTIES Bahrami S B; Kordestani S S; Mirzadeh H; Mansoori P Polyvinyl alcohol-chitosan blend films are prepared by casting the respective polymer solutions. The glutaraldehyde is used as a crosslinking agent. A series of PVA-chitosan blends is prepared by varying the ratio of the constituents. Mechanical and physical properties of blended films such as tensile properties in the dry and wet states water uptake surface tension and contact angle are characterised. Blending PVA and chitosan improves strength and flexibility of the films in the dry and wet states. Crosslinking with glutaraldehyde improves tensile strength and decreases elongation of the films. PVA content in the blends increases water uptake while crosslinking the films with glutaraldehyde causes less hydrophilicity. Water uptake in PVA-chitosan blends can be controlled by variation of their contents crosslinking agent and the pH of solution. Blending of PVA and chitosan improves bulk and surface hydrophilicity of blended films. 29 refs. Amirkabir University; Tehran University of Medical Science IRAN

Accession no. 895021 Item 316 Journal of Polymers and the Environment 11, No.1, 2003, p.7 STARCH POLY(LACTIC ACID) AND POLY(VINYL ALCOHOL) BLENDS Ke T; Sun X S Research on biogradable materials has been stimulated due to concern regarding the persistence of plastic wastes. Blending starch with polylactic acid (PLA) is one of the most promising efforts because starch is an abundant and cheap biopolymer and PLA is biodegradable with good mechanical properties. Polyvinyl alcohol (PVOH) contains unhydrolytic residual groups of acetate and also has good compatibility with starch. It is added to a starch and PLA blend (50:50 w/w) to enhance compatibility and improve mechanical properties. PVOH (Mw 6000) at 10% 20% 30% 40% 50% (by weight) based on the total weight of starch and PLA and 30% PVOH at various molecular weights (mw 6000. 25000 78000 and 125000 daltons) are added to starch/PLA blends. PVOH interacts with starch. At proportions greater than 30% PVOH form a continuous phase with starch. Tensile strength of the starch/PLA blends increases as PVOH concentration increases up to 40% and decreases as PVOH molecular weight increased.


The increasing molecular weight of PVOH slightly affects water absorption. Effects of moisture contents on the starch/PLA/PVOH blend are also explored. The blend containing gelatinised starch has higher tensile strength. However gelatinised starch also results in increased water absorption. 21 refs. Kansas State University USA

Accession no. 894980 Item 317 ACS Polymeric Materials Science and Engineering, Spring Meeting 86, 2002, p.263 EFFECTS OF DISSOLVING TEMPERATURE AND CONCENTRATION ON THE RHEOLOGICAL PROPERTIES OF POLY(VINYL ALCOHOL)(PVA) SOLUTIONS IN DIMETHYL SULFOXIDE(DMSO) Hak Sung Kim; Dong Wook Chae; Byoung Chul Kim Studies of the above effects were conducted in order to determine the optimal conditions for solution spinning of PVAl. The PVAl solution was found to be significantly affected by the concentration and dissolving temperature. With increasing concentration intermolecular hydrogen bonding and entanglement were increased. PVAl solutions of high concentrations had long relaxation time and could form an oriented structure at low frequency. It was however difficult to obtain fully extended chain of high modulus and strength PVAl fibre due to the high density of hydrogen bonding and entanglements. A PVAl solution dissolved at 120C had higher viscosity and stronger elastic properties than that dissolved at below 100C. 4 refs. KOREA

Accession no. 893206 Item 318 Journal of Applied Polymer Science 89, No.2, 2003, p.349 SYNTHETIC ABSORBENT FOR DYESTUFFS BASED ON GAMMA CROSSLINKED POLY(VINYL ALCOHOL) (PVA) Ibrahim S M The characterisation and uses of gamma radiationcrosslinked polyvinyl alcohol (PVA) films as absorbents for different classes of dyestuffs normally released from textile factors are reported. Dye stuffs are selected from different producers. These dyestuffs are Remacryl Blue (basic dye) Remazol Golden Orange (reactive dye) Solar Orange (direct dye) and Sandolan (acid dye). The percentage dye sorption by PVA is determined by spectroscopic and colourstrength measurements of the PVA films after absorbing the different dyestuffs. The results show that the concentration of dimethylbisacrylamide as a crosslinking agent has a great effect on the gel fraction and percentage swelling in water of the PVA polymer. In general crosslinked PVA

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shows a low tendency to absorb the different dyestuffs under investigation at room temperature. This tendency is shown to increase with an increasing temperature of the dye solution from room temperature to 70 deg.C. Meanwhile the highest percentage of dye sorption is found in the case of the basic dye and the lowest one in the case of the reactive dye depending on the active groups on the dyes. The percentage dye sorption by PVA is slightly higher in the acid medium rather than in the alkaline one. 12 refs. Egypt National Centre for Radiation Res.& Technol. EGYPT

Accession no. 892896 Item 319 US 6590013 B1 20030708 HARDENER FOR USE IN-UREAFORMALDEHYDE AND UREA-MELAMINEFORMALDEHYDE BASED ADHESIVES Andersen B; Brehmer B G A hardener for use in urea-formaldehyde and ureamelamine-formaldehyde based adhesives comprises a polyvinyl acetate emulsion together with a metal chloride and an ammonium salt. The adhesive composition comprises a urea-formaldehyde or urea-melamineformaldehyde resin and the hardener provides an increased cure rate an acceptable viscosity better adhesion and greater tolerance towards substrate type. DENMARK; EUROPEAN COMMUNITY; EUROPEAN UNION; SCANDINAVIA; USA; WESTERN EUROPE

Accession no. 892875 Item 320 Colloid and Polymer Science 281, No.6, 2003, p.580 POLY(VINYL ALCOHOL)/POLY(N-ISOPROPYLACRYLAMIDE) SEMI-INTERPENETRATING POLYMER NETWORK HYDROGELS WITH RAPID RESPONSE TO TEMPERATURE CHANGES Zhang J-T; Cheng S-X; Zhuo R-X A series of thermosensitive and fast-response polyvinyl alcohol (PVA)/poly(N-isopropylacrylamide (PNIPA) hydrogels are prepared by incorporating PVA into crosslinked PNIPA to form a semi-interpenetrating polymeric network (semi-IPN). Compared to the conventional PNIPA hydrogel the semi-IPN hydrogels thus prepared exhibit significantly faster response rates and undergo full de-swelling in 1 min (lose about 95% water within 1 min) when the temperature is raised above their lower critical solution temperature and have larger equilibrium swelling ratios at room temperature. These improved properties are attributed to the incorporation of PVA which forms water-releasing channels and results in increased hydrophilicity into the PNIPA hydrogel networks. 20 refs.

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Wuhan University CHINA

Accession no. 892810 Item 321 Journal of Applied Polymer Science 89, No.6, 2003, p.1573 PREPARATION AND CHARACTERIZATION OF MOLYBDOSILICIC ACID/POLY(VINYL ALCOHOL) FIBER MATS PRODUCED BY AN ELECTROSPINNING METHOD Jian Gong; Xiang-Dan Li; Bin Ding; Douk-Rae Lee; Hak-Yong Kim The preparation of high percentage (20-80 percent) molybdosilicic acid/poly(vinyl alcohol) (PVA) fibre mats using the electrospinning technique is described. The fibre mats were characterised by IR XRD SEM and DSC and the results show that the PVA changes from a semicrystalline to an amorphous state with increasing molybdosilicic acid. The swelling properties of the fibre mats in water were investigated and the results are discussed. 25 refs. Changchun Northeast Normal University; Chonbuk National University CHINA; SOUTH KOREA

Accession no. 891935 Item 322 ACS Polymeric Materials Science and Engineering, Spring Meeting 86, 2002, p.167 EFFECTS OF PVA ON THE PROPERTIES OF CELLULOSE/OVA SOLUTION BLENDS IN NMMO HYDRATE Seong Y-J; Kim B-C The effect of PVAL on the properties of cellulose/PVAL blend solutions was investigated in methylmorpholine oxide hydrate. Characterisation was undertaken using DSC X-ray diffraction and rheological measurements. 15 refs. KOREA

Accession no. 891632 Item 323 Proceedings of the TECH XXVI: LEARN TO SUCCEED held Washington, DC 2003, p.197 POLYMERIZATION REACTION MONITORING FOR PSA PRODUCTION USING AN ATR-FTIR PROBE Jovanovic R ATR-FTIR spectrometry was applied to the offline monitoring of solution polymerisations and copolymerisations of butyl acrylate and vinyl acetate and the data obtained used to establish real time in-situ monitoring of emulsion and mini-emulsion polymerisations. The performance of the analytical technique was compared



CANADA; USA

used to model the hydrolysis of polyvinyl acetate. Variance analysis is used in the study of dispersion of experimental data. The confidence level in this design is reported from total sum of the square and statistical calculations.


Tarbiat Modarres University

with traditional monitoring techniques namely gravimetry and PMR spectroscopy and limitations of the technique indicated. 7 refs.

IRAN

Item 324 Polymers for Advanced Technologies 14, No.6, 2003, p.422 PROPERTIES OF LOW-TEMPERATURE SWELLING HYDROGELS PREPARED WITH PARTIALLY SAPONIFIED PVA AND DRUG RELEASE USING THE HYDROGELS Horiike S; Yumoto K; Matsuzawa S; Yamaura K The preparation of low-temperature swelling hydrogels using partially saponified polyvinyl alcohol (PVA) with glutaraldehyde as crosslinking agent for use as drug delivery systems were investigated. The block copolymer character of the partially saponified PVAs was estimated by carbon-13C-NMR. The hydrogels showed repeatable temperature-dependent swelling-shrinking behaviour. The dependence of drug absorption and release on the degree of polymerisation was studied using various drugs including para-acetamidophenol and insulin. 11 refs. Shinshu University JAPAN

Accession no. 891115 Item 325 US 6569801 B2 20030527 ADHESIVE MADE FROM CROSS-LINKING LIQUID CATALYST WITH AMINO RESIN Berube S; Cutt J The liquid catalyst has improved flexibility and adhesive properties which are imparted to the adhesive. The adhesive is composed of a crosslinkable polyvinyl acetate an acid and an ammonium salt. USA

Accession no. 890843 Item 326 Iranian Journal of Polymer Science and Technology 15, No.5, Dec.2002-Jan.2003, p.3011 EXPERIMENTAL DESIGN FOR POLYMERISATION REACTION AND HYDROLYSIS OF POLYVINYL ACETATE Semsarzadeh M A; Gangi H Statistical empirical design is based on the statistical modelling of non-linear polynomial equation and coding of these equations in the solution polymerisation of vinyl acetate in a factorial design. The surface calculation considers time temperature and percent conversion as important factors in this polymerisation reaction. In response the influence of these factors is determined from the polynomial equations. Non-linear regression is also


Accession no. 890222 Item 327 Journal of Industrial Textiles 32, No.3, 2003, p.223 USE OF ATMOSPHERIC PRESSURE PLASMA TREATMENT IN DESIZING PVA ON VISCOSE FABRICS Cai Z; Qiu Y; Hwang Y J; Zhang C; McCord M Both air-oxygen-helium and air-helium atmospheric pressure plasma treatments are employed to desize PVA on a rayon (viscose) fabric. Both plasma treatments are able to remove some of the PVA on the rayon fabric and increase PVA solubility in cold water resulting in a higher weight loss in cold washing. The effect of the atmospheric pressure plasmas becomes greater as the treatment time increases. Plasma treatment followed by one cold and one hot washing has the same effect as conventional chemical treatments followed by two cycles of cold and hot washing. The atmospheric plasma treatment does not have negative effect on rayon fabric tensile strength. 13 refs. Shanghai Donghua University; North Carolina State University CHINA; USA

Accession no. 890213 Item 328 Proceedings of the conference held San Francisco, CA, 163rd ACS Rubber Division Meeting, Spring 2003, Paper 19 REINFORCEMENT AND NONLINEAR VISCOELASTICITY OF POLYMER MELTS CONTAINING MIXTURES OF NANOFILLERS Sternstein S S; Ramorino G; Jiang B; Ai-Jun Zhu The reinforcement of composites of poly(vinyl acetate) with binary filler pairs prepared by solution blending was studied experimentally by determining storage modulus loss modulus and loss factor and comparing the results with the predictions of a simple mixing rule model. It was found that an interaction term specific to each binary filler/matrix system was needed to predict storage moduli. Possible mechanisms by which the secondary filler affects reinforcement by the primary filler are discussed. 8 refs. USA

Accession no. 889974 Item 329 Colloid and Polymer Science 281, No.4, 2003, p.337

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STUDY ON THE INITIAL STAGE OF EMULSION POLYMERIZATION OF VINYL ACETATE USING POLY(VINYL ALCOHOL) AS A PROTECTIVE COLLOID Suzuki A; Yano M; Saiga T; Kikuchi K; Okaya T A model experiment of emulsion polymerisation of vinyl acetate (VAc) is carried out using polyvinyl alcohol (PVA) as a protective colloid where a small amount of VAc (1 ml/100 ml water) is employed. This corresponds to the initial stage of the emulsion polymerisation. In the presence of the large amounts of PVA the number of new particles smaller than 80 nm continues to increase during the polymerisation while there is not much increase in the particle diameter. In contrast in the absence of PVA the particles formed at the very early stage continue to grow and the number of particles does not increase by so many. The fractionation of the polymers in the emulsion reveals that more than 90% of polymerised VAc and more than 70% of the PVA used are grafted. To realise these results the reaction times of three elemental reactions are calculated i.e. the initiation reaction of the sulphate radical with Vac the propagation of the PVAc radical and the hydrogen abstraction from the PVA with the sulphate radical. The time of the entry of the sulphate radical into a particle is 10-4 s. Hydrogen abstraction from PVA with the sulphate radical is the fastest reaction which results in the grafting onto PVA while the initiation reaction which results mainly in homopolymer is slower. The propagation of the PVAc radical in the aqueous phase is a much slower reaction. The grafted molecules coagulate with each other to become a particle. 12 refs. Shiga Prefecture University JAPAN

Accession no. 889407 Item 330 Journal of Macromolecular Science A A40, No.3, 2003, p.211 GRAFT COPOLYMERISATION OF METHYL ACRYLATE ONTO POLY(VINYL ALCOHOL) INITIATED BY POTASSIUM DIPERIODATOCUPRATE(III) Liu Y; Liu X; Deng K; Liu Z; Yang L A novel redox system potassium diperiodatocuprate(III) (Cu(III))-polyvinyl alcohol (PVA) redox system is employed to initiate the graft copolymerisation of methyl acrylate (MA) onto PVA in alkaline medium. The grafting parameters vary with concentrations of monomer initiator macromolecular backbone (DP = 1750 M = 80000) and temperature. The formation of the graft copolymer is confirmed by Fourier transform infrared spectroscopy scanning electron microscopy X-ray diffraction and thermogravimetric analysis. It is found that (Cu(III))PVA system is an efficient redox initiator for this graft copolymerisation. A mechanism is introduced to explain the formation of radicals and the initiation. At the same time

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the other acrylate monomers such as methyl methacrylate ethyl acrylate and n-butyl acrylate are used as reductant to produce graft copolymerisation. It is definitely observed that these reactions can occur in some degree. Thermal stabilities are checked by TGA and this indicates that graft copolymer is resistant to moisture absorption. 24 refs. Hebei University CHINA

Accession no. 889260 Item 331 Polymer Preprints 2002, 43, No.2, p.289 INFLUENCE OF NITROXYL RADICAL STRUCTURE ON CONTROLLED RADICAL HOMO- AND COPOLYMERIZATION OF DIFFERENT VINYL MONOMERS: EXPERIMENTAL AND QUANTITATIVE INVESTIGATIONS Grishin D F; Kolyakina E V; Pavlovskaya M V; Semionycheva L L; Razuvaev A G 2-Methyl-2-nitrosopropane phenyl-N-tert-butylnitrone and 1-tert-butyl-3-phenyl-1-oxytriazene were evaluated as alternatives to the use of 2266-tetramethylpiperidinyl1-oxy/benzoyl peroxide for the controlled radical polymerisation of vinyl monomers (methyl methacrylate butyl methacrylate butyl acrylate styrene vinyl chloride and vinyl acetate) at temperatures in the range 50-70 C. From considerations of the polymerisation kinetics and molecular weight of the resulting polymers it was concluded that sterically hindered higher molecular weight nitroxyl macroradicals produced in the course of polymerisation were more effective in controlling chain growth over the temperature range 50-70 C than their low molecular weight analogues. This observation was supported by quantum chemical calculations. 10 refs. RUSSIA

Accession no. 889150 Item 332 Journal of Polymer Science: Polymer Chemistry Edition 41, No.8, 2003, p.1107 NOVEL APPROACH TO THE CHEMICAL MODIFICATION OF POLY(VINYL ALCOHOL): PHOSPHORYLATION Liu Y-L; Chiu Y-C The chemical modification of polyvinyl alcohol (PVA) is performed through oxidation followed by nucleophilic addition. PVA is oxidised by KMnO 4 to form vinyl ketone units along the polymer backbone. The chemical modification of PVA is then conducted through the reaction of the carbonyl group of the vinyl ketone unit with 910-dihydro-9-oxa-10-phosphaphenanthrene-10oxide (DOPO) as a nucleophile. Through this approach the phosphorous DOPO group is attached onto the carbon atom



of the polymer main chain rather than onto the pendent hydroxyl groups of PVA. The formed DOPO-containing PVA shows improved thermal stability organosolubility and flame retardance. 29 refs. Chung Yuan Christian University CHINA

Accession no. 87877

hydrogel to absorb water was therefore high. Water absorption was determined gravimetrically as a function of time at room temperature. Characterisation of the equilibrium swelling ratio and compressive modulus was carried out for all the resulting PVA hydrogels and these were related to the network structure. 20 refs. Tarragona Universitat Rovira I Virgili EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE

Item 333 Reactive and Functional Polymers 55, No.1, 2003, p.61 SYNTHESIS AND CHARACTERISTICS OF INTERPENETRATING POLYMER NETWORK HYDROGELS COMPOSED OF POLY(VINYL ALCOHOL) AND POLY(NISOPROPYLACRYLAMIDE) Seon Jeong Kim; Sang Jun Park; Sun I Kim


The characteristics of this interpenetrating polymer network (IPN) were investigated using FT-IR and differential scanning calorimetry. A hydrogel IPN combining polyvinyl alcohol and poly(n-isopropylacrylamide) was chosen for testing because of interesting response to temperature swelling in water below the lower critical solution temperature (LCST) and shrinking above the LCST which could offer applications in biomedical areas. Two sister papers published alongside this paper investigated other IPN systems. The hydrogel IPNs used in this case were synthesised using three different ratios of polymers. Polymerisation was carried out using the sequential IPN method. Firstly the PVA was polymerised in the presence of the other monomer using glutaraldehyde as a crosslinker and catalyst then the second monomer was polymerised. Swelling in water was investigated at varying pH and temperature and the proportion of free and bound water was determined. The hydrogel with the lowest proportion of PVA (50%) gave the highest swelling ratio. 29 refs. Hanyang University

Collins S; Rimmer S

SOUTH KOREA

Accession no. 887742 Item 334 Journal of Applied Polymer Science 88, No.13, 2003, p.3026 NETWORK CHARACTERIZATION AND SWELLING BEHAVIOUR OF CHEMICAL HYDROGELS BASED ON ACID-CONTAINING POLY(VINYL ALCOHOL) Ruiz J; Mantecon A; Cadiz V Poly(vinyl alcohol) (PVA) was modified with phthalic and succinic anhydride to yield vinyl alcohol-vinyl ester copolymers that contain carboxylate groups. Crosslinking of these half-esters was then achieved by using poly(ethylene glycol) (PEG) 400 diglycidylether. To obtain low degrees of crosslinking low crosslinker/ carboxylate ratios were used The capacity of the resulting


Item 335 Polymer Preprints 2002, 43, No.2, p.1085 SYNTHESIS OF HYDROXY TERMINATED POLY(VINYL ACETATE) BY CHAIN TRANSFER TO SOLVENT

Vinyl acetate was polymerised in two alcoholic solvents capable of acting as chain transfer agents isopropanol and 2-isopropoxyethanol producing poly(vinyl acetate) with hydroxy terminal groups. AIBN was used as the initiator. The polymers were characterised by size exclusion chromatography and vapour pressure osmometry. The chain transfer coefficient was derived by comparing the degree of polymerisation with the solvent and monomer concentrations according to the differentiated form of the Mayo equation. The results followed the Mayo equation when 2-isopropoxyethanol was used as a solvent but some deviation was seen in the case of isopropanol. It was suggested that this deviation was the result of multiple transfers to solvent. 2 refs. EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE

Accession no. 886541 Item 336 Polymer Preprints 2001, 42, No.2, p.653 VAPOR DETECTION USING ARRAYS OF CONDUCTING POLYMER COMPOSITE CHEMIRESISTORS Lewis N S; Briglin S; Freund M S; Hopkins A Vapour detection was performed using arrays of conducting polymer composite chemiresistors. The polymers used as sensors included poly(4-vinyl phenol) poly(styrene-coallyl alcohol) poly(methyl styrene) poly(vinyl chloride-covinyl acetate) poly(vinyl acetate) poly(N-vinylpyrrolidone) poly(ethylene oxide) poly(carbonate bisphenol A) poly(styrene) and poly(caprolactone). It was found that detector arrays fabricated from conducting polymer composites provide a convenient low power flexible implementation for vapour detection. Improved diversity in the detector array can be obtained through a broad selection of polymers polymer blends and plasticisers. These arrays offer an opportunity for developing pattern-recognition

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based approaches to vapour detection using combinatorial chemistry techniques in polymer fabrication and sensor preparation. 12 refs. Accession no. 885754 Item 337 Polymer Testing 22, No.4, 2003, p.381 CHARACTERISATION OF BETA-CHITIN/ POLY(VINYL ALCOHOL) BLEND FILMS Peesan M; Rujiravanit R; Supaphol P Blend films of beta-chitin (poly(N-acetyl-D-glucosamine)) and poly(vinyl alcohol) (PVAL) of differing compositions were prepared by solution-casting from solutions of beta-chitin and PVA in concentrated formic acid. It was observed that films prepared from pure beta-chitin and pure PVA were transparent but the film having 50/50 composition was cloudy. The effect of blend composition on physical thermal and mechanical properties morphology and swelling behaviour was investigated and the results compared to those for the pure components. For example DSC measurements showed that glass transition temperatures of the blend films increased with increasing beta-chitin content while melting temperatures tended to decrease. 17 refs. Chulalongkorn University THAILAND

Accession no. 885416 Item 338 Polymers for Advanced Technologies 14, No.2, 2003, p.79 INFLUENCE OF A ZWITTERIONIC SURFACTANT ON THE CHROMOGENIC BEHAVIOR OF A DYE-CONTAINING AQUEOUS PVA-POLYETHER GEL NETWORK Kriwanek J; Lotzsch D; Vetter R; Seeboth A The effect of the addition of a zwitterionic sulphobetaine to a dye-containing polymer gel composed of two polymers - polyvinyl alcohol (PVA) and polyether - is investigated. With increasing sulphobetaine content a remarkable reduction of the UV-vis-absorption intensity of the longest wavelength absorption band of Phenol Red in the aqueous polymer network is observed even for sulphobetaine concentrations below its critical micelle concentration (cmc). It can be assumed that this effect is based on the formation of ionic complexes dye molecules and either single sulphobetaine molecules or aggregates of sulphobetaine. Furthermore thermotropic behaviour occurs in the investigated polymer gel even at a polyether concentration as low as 0.8 wt.%. 10 refs. Fraunhofer Institute For Applied Polymer Research EUROPEAN COMMUNITY; EUROPEAN UNION; GERMANY; WESTERN EUROPE


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Item 339 Journal of Applied Polymer Science 88, No.1, 2003, p.104 ELECTRON SPIN RESONANCE AND ULTRAVIOLET SPECTRAL ANALYSIS OF UV-IRRADIATED PVA FILMS FILLED WITH MNCL2 AND CRF3 Zidan H M PVAl films containing various contents of chromium fluoride and manganese chloride were prepared and the structural modification that occurred due to filling with different levels and/or UV irradiation was studied using ESR and UV-visible spectroscopies. The ESR analysis revealed that the spin configuration of chromium fluoride- manganese chloride- and cobalt bromide-filled PVAl differed. The filling level dependence of the ESR parameters was investigated. The UV-visible spectral analysis for pure PVAl showed absorption bands at 265 and 280 nm which were assigned to the presence of carbonyl groups. The addition of chromium fluoride led to the appearance of other bands at 418 and 596 nm. The addition of manganese chloride led to a new band at about 350 nm due to charge transfer transition. The results indicated that the Cr3+ or Mn2+ were present in the octahedral symmetrical form within the PVAl matrix. SEM micrographs of chromium fluoride-filled PVAl were examined. 23 refs. Mansoura University EGYPT

Accession no. 883213 Item 340 Polymers for Advanced Technologies 13, No.10-12, 2002, p.938 BIODEGRADABLE COMB POLYESTERS CONTAINING POLYELECTROLYTE BACKBONES FACILITATE THE PREPARATION OF NANOPARTICLES WITH DEFINED SURFACE STRUCTURE AND BIOADHESIVE PROPERTIES Breitenbach A; Jubg T; Kamm W; Kissel A major challenge in oral peptide and protein delivery remains the search for suitable carrier systems. Therefore a new concept is investigated combining a modified 3D architecture increased hydrophilicity of polylactic coglycolic acid (PLGA) and charged groups in a single polymer. Biodegradable comb PLGA synthesised by grafting short PLgA chains onto different polyvinyl alcohol-based backbone polyols poly(2-sulphobutyl-vinyl alcohol) and polydiethylaminoethyl-vinyl alcohol. The polyelectrolyte backbones are obtained by etherification of PVA with charge-containing pendent groups. The comb polymer structure can be confirmed by NMR IR spectroscopy differential scanning calorimetry elemental analysis and measurement of intrinsic viscosity. Nanoparticles (NP) as potential mucosal carriers systems are prepared by controlled precipitation and investigated



as a function of polymer composition. The amphiphilic character and the 3D architecture of the novel polyesters allow the preparation of small nanoparticles even without the use of surfactants. Surface NMR surface charge and hydrophobicity determination indicate a core-corona-like NP structure especially in the case of charged polyesters. A structural model is proposed for the NP with an inner polyester core and an outer charged-groups-containing surface depending on polymer composition and backbone charge density. The higher the polymer backbone charge density the more pronounced its influence on the nanoparticle surface properties. The possibility of preparing NP without the use of a surfactant as well as of designing the NP surface characteristics by polymer backbone charge density and polymer hydrophilic-hydrophobic balance will be a major or advantage in protein adsorption bioadhesion and organ distribution. This makes these biodegradable polymers promising candidates for colloidal protein and peptide delivery. 31 refs. Marburg Philipps Universitat EUROPEAN COMMUNITY; EUROPEAN UNION; GERMANY; WESTERN EUROPE


Iowa State University USA

Accession no. 880925 Item 342 Materiale Plastice 39, No.4, 2002, p.202 STUDY OF THE OPTICAL PROPERTIES OF SOME COMPOSITE BASED ON GELLAN AND ELECTROACTIVE SYNTHETIC POLYMERS Strat M; Strat G; Gutlui S; Alupei C The results of an investigation on the preparation characterisation and determination of optical properties of gellan-polyvinyl alcohol (PVA) gellan-poly(N-vinyl pyrrolidone) (PVP) and gellan-poly(N-vinyl imidazole) (PVI) composites are described; it represents part of a major work dedicated to the development of a new source of dielectric biomaterials for medical devices. The choice of PVA PVP and PVI is based on the fact that these materials polymers are good electroactive synthetic polymers. 3 refs. Jassy, Cuza Al.I.University; Asachi G.Technical University EASTERN EUROPE; RUMANIA

Item 341 Journal of Polymers and the Environment 10, No.1-2, 2002, p.31 PROCESSING AND PHYSICAL PROPERTIES OF PLASTICS MADE FROM SOY PROTEIN POLYESTER BLENDS Mungara P; Chang T; Zhu J; Jane J Blends of soy protein and biodegradable polyesters (Biomax and polycaprolactone) were prepared. The blends were prepared in either a one-step or a two-step compounding extrusion process. The compatibiliser used in this study was polyvinylpyrrolidone (PVP). Poly(vinyl alcohol) (PVA) or polycaprolactone (PCL) were used to plasticise the Biomax; glycerol was used as a plasticiser for the soy formulations. The blend pellets formed were then used to produce injection-moulded tensile bars. The mechanical properties (ASTM D638-86) water absorption (ASTM D 570) thermal properties (DMA) and structure (SEM) were analysed. The blends demonstrated high tensile strength (16 - 22 MPa for PVA blends; 27 - 33 MPa for PCL blends). PVA blends having the highest percentages of the synthetic polymer had the greater strengths. All the blends had high Young's moduli but had brittle characteristics (elongation at break 1.8 - 3.1 percent). The blends showed low water absorption and good stability under ambient conditions compared to plastics made from soy protein alone. The lowest water absorption was observed for blends made from soy protein flour. SEM micrographs for all the blends showed that the synthetic polymers were dispersed homogeneously throughout the protein matrix in each case. 15 refs.


Accession no. 880370 Item 343 ACS Polymeric Materials: Science and Engineering, Spring Meeting 84, 2001, p.798 CONTROLLING THE MORPHOLOGY OF CALCIUM CARBONATE CRYSTALS USING MULTIFUNCTIONAL MACROMOLECULAR ADDITIVES Valiyaveettil S; Lakshminarayanan R Biological organisms have evolved strategies to control the structure and morphology of the minerals using a wide variety of proteins. They use the inorganic minerals for different purposes. A number of synthetic templates such as molecular ribbons surfactants Langmuir monolayers self-assembled monolayers natural and synthetic polymers in the form of fibres and films and hydrophilic block copolymers have been used in recent years to mimic biomineralisation which has many technological advantages. The use of polyvinyl alcohol and sodium silicate as template for the nucleation and morphology control of calcium carbonate crystals is reported. The use of multi functional polyvinyl alcohol (PVA) and sodium silicate (NaSi) as template for the studies is motivated by their existing industrial applications. The aim is to establish the influence of these water-soluble additives in nucleating a specific polymorph and directing the formation of a specific morphology of the calcium carbonate crystals. Neutral organic polymeric additives and anionic inorganic additives exhibiting complex solution properties behave differently in the nucleation of

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various polymorphs of calcium carbonate crystals. While PVA additives favoured the nucleation of aragonite phase the silicate additive induces an oriented nucleation of the calcite crystals. In both cases it is believed that the selfassembly of additives plays a major role in controlling the nucleation and morphology of calcium carbonate polymorphs. The role of molecular conformation of these additives is currently being established in nucleation of various polymorphs as well as in deciding the morphology of the crystals. 14 refs. SINGAPORE

Accession no. 880228 Item 344 ACS Polymeric Materials: Science and Engineering, Spring Meeting, Proceedings of a conference held San Diego, CA 84, 2001, p.1057 DIALDEHYDES AS CROSSLINKING AGENTS FOR IMPROVED PAPER WET STRENGTH Xu G G; Yang C Q Improvements in the wet strength and dry strength including tensile strength and folding endurance of paper treated with a combination of dialdehydes (glutaraldehyde or glyoxal) with polyvinyl alcohol (PVA) were investigated. Effects of cure time and temperature on the crosslinking reaction with the cellulose were also examined. It was shown that a combination of PVA with glutaraldehyde proved the more efficient at improving the wet and dry performance of the paper. 9 refs. USA

Accession no. 879390 Item 345 Proceedings of the 60th SPE Annual Technical Conference (ANTEC 2002) held San Francisco, CA Paper 505 Session T51-Flexible Plastics Packaging, Barrier Packaging Materials and Applications EFFECT OF HIGH BARRIER EMULSION POLYMERS ON THE REDUCTION IN WATER VAPOUR TRANSMISSION RATES OF LAMINATED CARTON Lendrum S; Ryan N M; McNally G M Two ply laminated carton boards were prepared by bonding 300 or 350 g/m2 board using a variety of polymers which acted as both adhesive and water vapour barrier. The polymers were: commercially available emulsion grades of ethylene-vinyl alcohol (EVOH) copolymer poly(vinylidene chloride) tetrafluoroethylene-hexafluoropropylenevinylidene fluoride terpolymer; and poly(vinyl alcohol) commercial adhesives. The water vapour permeabilities of the prepared boards were measured at 60% RH and 20 C. The permeability decreased with increasing polymer layer thickness and it was possible to achieve the market requirements for a permeability of 20-50 g/m2/24 h. EVOH gave the lowest permeability. 6 refs.

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EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE

Accession no. 879110 Item 346 High Performance Polymers 14, No.3, 2002, p.261 PROPERTIES OF THE INTERPENETRATION POLYMER NETWORK HYDROGELS COMPOSED OF POLY(VINYL ALCOHOL) AND POLY(DIALLYLDIMETHYLAMMONIUM CHLORIDE) Kim S J; Yoon S G; Kim S L Temperature- and pH-responsive interpenetrating polymer network (IPN) hydrogels constructed with polyvinyl alcohol (PVA) and polydiallyldimethylammonium chloride (PDADMAC) using the sequential IPN method are studied. The characterisations of IPN hydrogels are investigated using Fourier transform infrared spectroscopy and differential scanning calorimetry. IPN hydrogels exhibit a relatively high swelling ratio 180-360% at room temperature. The swelling ratio for the hydrogels depend on pH and temperature. DSC is used to determine the amount of free water in IPN hydrogels. The amount of free water increases with increasing PDADMAC content in the IPN hydrogel. 19 refs. Hanyang University KOREA

Accession no. 877789 Item 347 Journal of Applied Polymer Science 87, No.8, 2003, p.1239 PREPARATION OF MAGNETIC POLYVINYL ALCOHOL MATERIALS BY IN SITU SYNTHESIS OF MAGNETITE IN A PVA MATRIX Lin H; Watanabe Y; Kimura M; Hanabusa K; Shirai H Nanosized magnetite particles were synthesized in situ within PVAL solutions by precipitating ferrous ions or a mixture of ferrous and ferric ions with sodium hydroxide solution. Transparent films were obtained by a casting method and six kinds of magnetic PVAL fibres were also prepared by a wet-spinning method. Mechanical properties were measured. 29 refs. Shinshu University JAPAN

Accession no. 876923 Item 348 Adhesion '02, Proceedings of EURADH 2002 held in Glasgow 2002, p.49 FRACTURE ANALYSIS AND TESTING OF WOOD-ADHESIVE BONDS FOR TIMBER ENGINEERING APPLICATIONS Serrano E; Gustafsson P J



The results are reported of an investigation of the fracture of wood finger-joint specimens reinforced with either threaded steel rods or smooth glass fibre-reinforced polyester rods and bonded with various adhesives. Adhesives employed were phenol-resorcinol-formaldehyde two-component PU or polyvinyl acetate. The strength fracture energy and shapes of the stress-slip relations for the specimens were determined and a constitutive model which includes a total of 4 independent material parameters (shear strength and fracture energy in shearing (Mode II) and normal strength and fracture energy in opening mode (Mode I)) developed to predict the behaviour of the wood-adhesive joints. 5 refs. EUROPEAN COMMUNITY; EUROPEAN UNION; SCANDINAVIA; SWEDEN; UK; WESTERN EUROPE


to fall when the initiator concentration exceeded 3.3-3.5 x 10-4 mol/L. With increasing concentration of PVA the graft efficiency gradually decreased. Studies were carried out on the rheological behaviour mechanical properties and morphological properties of resins. The rheological behaviour deteriorated with increasing content of chlorinated polyethylene and the melt was a pseudo-plastic liquid. As the content of chlorinated polyethylene increased the impact strength of graft-type ACS resin increased. The rheological properties and impact characteristics of alphamethyl styrene-containing ACS resin improved because of the introduction of alpha-methyl styrene and overall properties were optimised at the 5% alpha-methyl styrene content of ACS resin. 18 refs. Hebei University CHINA

Accession no. 873381 Item 349 Journal of Membrane Science 209, No.1, 2002, p.271 FLAKE-FILLED REACTIVE MEMBRANES Lape N K; Yang C; Cussler E L Aligned mica flakes and colloidal zinc oxide can combine to reduce the acid permeability and increase the lag time in polyvinyl alcohol (PVA) membranes. The permeability is reduced up to ten times by the flakes but is affected much less by the zinc oxide. The lag times are increased by up to 1000 times by a combination of flakes and reaction. The results can be estimated with theories for this transport including variations with the square of the volume fraction of flakes and the first power of zinc oxide concentration. These estimates are successful only when the flakes are evenly distributed within the membrane. When they are unevenly distributed the apparent membrane permeability behaves differently. While the experiments use only PVA as a polymer the same flakes and reactants will give the same relative permeability reductions with other less permeable polymers. 40 refs. Minnesota University USA

Accession no. 873793 Item 350 Polymer Plastics Technology and Engineering 41, No.5, 2002, p.863 SYNTHESIS RHEOLOGICAL BEHAVIOUR AND MECHANICAL PROPERTIES OF GRAFT-TYPE ACS RESIN Gao J; Sun S; Li D; Yang L Using suspension polymerisation synthesis of graft-type ACS resin (acrylonitrile-chlorinated polyethylene-styrene terpolymer) and alpha-methyl styrene-containing ACS was carried out with particular attention paid to the effect of concentration of initiator and polyvinyl alcohol (PVA) on the reaction. With increasing concentration of initiator in the first stage the graft efficiency increased but it began


Item 351 ISO/DIS 15023-2. PLASTICS - POLY(VINYL ALCOHOL) (PVAL) MATERIALS - PART 2: DETERMINATION OF PROPERTIES Version 50.00 (2002). SWITZERLAND; WESTERN EUROPE

Accession no. 873105 Item 352 Journal of Applied Polymer Science 86, No.11, 2002, p.2854 PROPERTIES OF MODIFIED POLY(VINYL ALCOHOL) MEMBRANES PREPARED BY THE GRAFTING OF NEW POLYELECTROLYTE COPOLYMERS FOR WATER-ETHANOL MIXTURE SEPARATION Wen-Yen Chiang; Yi-Haw Lin Graft copolymers were synthesised by the reaction of PVAL with poly(sodium salt styrene sulphonic acid-comaleic acid) (PSStSA-co-MA). Membranes of PVAL-gPSStSA-co-MA formed a crosslinking network after heat treatment. Crosslinking enhanced the water insolubility and mechanical strength whilst retaining a high affinity towards water. The difference in the hydrogen bonding interactions between the membrane and water and the membrane and alcohol (methanol ethanol or isopropanol) showed that the membrane showed selective permeability towards water in a water-alcohol solution. The permeation flux decreased and the separation factor increased as the PSStSA-co-MA (crosslinking agent) content increased. 17 refs. Tatung University TAIWAN

Accession no. 872968 Item 353 Journal of Sol-Gel Science and Technology 25, No.2, 2002, p.103

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PREPARATION AND CHARACTERISATION OF POROUS FILMS BY A MODIFIED BASECATALYSED SOL-GEL PROCESS CONTAINING PVA; II. FILM PREPARATION Liu Y; Chen H; Zhang L; Yao X Porous SiO2 films are successfully deposited on silicon substrates by a modified base-catalysed sol-gel process (MBCP) containing polyvinyl alcohol (PVA). The process conditions such as gelation time synthesis temperature stabilising agent of the precursor solution and spin coating speed heat-treatment annealing temperature of the film on the microstructure and porosity of porous SiO2 films are systematically investigated by SEM XRD and ellipsometry techniques. A novel preparation technique for porous SiO2 film is presented. Using this process the resultant film can reach a thickness of 3.6 μm for one layer a porosity of 2550% a low thermal conductivity of 0.11 W/m.K. This film will be used as a low dielectric layer and thermal-insulating layer and a low refractive index layer. 11 refs. Canberra Australian National University; Xian Jiaotong University; Tongji University AUSTRALIA; CHINA

Accession no. 871889 Item 354 Journal of Sol-Gel Science and Technology 25, No.2, 2002, p.95 PREPARATION AND CHARACTERISATION OF POROUS SILICA FILMS BY A MODIFIED BASECATALYSED SOL-GEL PROCESS CONTAINING PVA. I. PRECURSOR SOLUTION SYNTHESIS Liu Y; Chen H; Zhang L; Yao X A novel modified base-catalysed sol-gel process containing polyvinyl alcohol (PVA) is proposed to prepare the porous SiO2 film. In this process the growth of the sol particles is artificially broken off and controlled by acid-stabilising agent and PVA. As a result a uniform and stable precursor solution is obtained in which the size of sol particles is stable. This new process efficiently overcomes the shortcomings of the traditional base-catalysed sol-gel process and can be employed to prepare porous SiO2 films with desired porosity and thickness. The influence of catalyst reaction temperature pH value stabilising agent and PVA additive on the size of the SiO2 sol particles is systematically studied. 22 refs. Canberra Australian National University; Xian Jiaotong University; Tongji University AUSTRALIA; CHINA

Accession no. 871888 Item 355 Synthetic Metals 130, No.2, 2002, p.121 LUMINESCENCE INTENSITY ENHANCEMENT INDUCED BY LASER IRRADIATION IN

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POLY(VINYL ALCOHOL) AND POLY (3-THIOPHENEACETIC ACID)BLEND De Souza J M; Dos Anjos P N M; Pereira E C Photoluminescence (PL) of polymeric blends with polyvinyl alcohol (PVA) and poly(3-thiopheneacetic acid) (PTAA) is investigated. An increase in the PL intensity induced by laser irradiation is found. The PL quantum efficiency is dependent on irradiation time laser intensity and PTAA doping state (acid or salt). PL intensity increases up to 200% for acid PTAA and 50% for salt PTAA. The PL efficiency relative enhancement is 314% for acid PTAA and 140% for salt PTAA. Using IR spectroscopy this effect is related to hydrogen bond interaction between PTAA and PVA excited states induced by laser irradiation that reduce the non-radiative decay rate. 25 refs. Sao Carlos Universidade Federal BRAZIL

Accession no. 870543 Item 356 US 6440259 B1 20020827 ONE-PART STORAGE-STABLE WATER-BASED CONTACT ADHESIVE COMPOSITION WITH AN INTERNAL COAGULANT Patel V The contact adhesives comprises an adhesive component comprising polychloroprene rubber and an internal coagulant. They may also contain a resinous component selected from the group consisting of ethylene-vinyl acetate copolymer polyvinyl acetate homopolymer polyvinyl acetate copolymer acrylic copolymer polyvinyl acetate acrylic copolymer and combinations thereof. The internal coagulant may be hygroscopic salt amino acid or a combination thereof. USA

Accession no. 870289 Item 357 Kobunshi Ronbunshu 59, No.9, 2002, p.511 PREPARATION OF COMPOSITE FILM USING WASTE PULP Hadano S; Onimura K; Yamasaki H; Tsutsumi O Treated waste pulp (pulp) is used as a cellulosic material. Water-soluble cellulose (PSAAc) is synthesised by acetylation of cellulose succinate. Composite films are prepared from PSAAc and polyvinyl alcohol (PVA) by a casting method and crosslinked by heating or reacting with hexamethylene diisocyanate (HDI). These films are homogeneous and transparent. Three types of homogeneous films - non-treated film HDI-treated film and heat-treated film and heterogeneous film obtained from pulp and PVA are used for tensile strength and biodegradation tests. HDI-treated film shows the highest elongation (592%). On the other hand the heat-treated film



and the heterogeneous film are fragile. The biodegradation test in soil gives the following order of weight loss for composite films: heterogeneous film greater than nontreated film greater than HDI-treated film greater than heat-treated film. 8 refs. Yamaguchi University; Ube National College of Technology JAPAN

Accession no. 869594 Item 358 Journal of Applied Polymer Science 86, No.3, 2002, p.622 PREPARATION PHYSICO-CHEMICAL CHARACTERIZATION AND OPTICAL ANALYSIS OF POLYVINYL ALCOHOLBASED FILMS SUITABLE FOR PROTECTED CULTIVATION De Prisco N; Immirzi B; Malinconico M; Mormile P; Petti L; Gatta G A subject of considerable interest from the environmental perspective is the use of biodegradable films for mulching. This is also of interest in terms of the intrinsic properties that such films might have when appropriately designed. Starting with existing biodegradable polymers a synthetic approach has been developed that leads to a new material characterised by a time-controlled biodegradation. The concept was to bridge polyvinyl alcohol (PVOH) chains through polycaprolactone (PC) crosslinks. In this manner PVOH loses its water sensitivity and can stand on the ground for the time required for mulching to occur while the PCL crosslinks being sensitive to a slow fungal attack will undergo cleavage followed by the complete bio-assimilation of the residual PVOH chains. Time of biodegradation can be controlled by the number of crosslinks introduced. The polymers were characterised for their intrinsic chemical-physical properties while a preliminary evaluation of their efficiency as mulches was achieved through the analysis of their thermal behaviour when deposited on an irrigated soil. The results were compared with a model approach capable of predicting the thermal behaviour of a film in particular environments. 13 refs. Instituto Di Ricerca e Tecnologia Delle Materie Plastiche; Basilicata University; Italy National Research Council EUROPEAN COMMUNITY; EUROPEAN UNION; ITALY; WESTERN EUROPE

Accession no. 868951 Item 359 Macromolecular Chemistry and Physics 203, No.10-11, 2002, p.1526 BIODEGRADATION OF POLY(VINYL ALCOHOL) IN SOIL ENVIRONMENT: INFLUENCE OF NATURAL ORGANIC FILLERS AND STRUCTURAL PARAMETERS


Corti A; Cinelli P; D'Antone S; Kenawy E-R; Solaro R Biodegradation of polyvinyl alcohol (PVA) films in blends with natural polymers such as gelatin and lignocellulose by-products and with polyvinyl acetate was studied under simulated soil burial conditions by determination of evolved carbon dioxide. The influence of residual acetyl groups in the PVA was also examined and appeared to have a positive influence on biodegradation. The effect of each blend component on the biodegradation was considered and it was determined that biodegradation of PVA and PVA blends under soil burial conditions is quite limited. The PVA appears to depress biodegradability of the other components of the blend compared to that of the pure component although an increase in hydrophobic character of the blend component appears beneficial. 27 refs. Pisa University EUROPEAN COMMUNITY; EUROPEAN UNION; ITALY; WESTERN EUROPE

Accession no. 868920 Item 360 Polymer Preprints 2000, 41, No.1, p.66 INVESTIGATION OF LATEX COPOLYMERS AND TERPOLYMERS CONTAINING NEO VINYL ESTERS FOR ARCHITECTURAL COATING APPLICATIONS Yang H W; Swarup V; Ellis P S; Subramanian R; Smith O W; Thames S F The performance of branched neo vinyl esters (formed from neo acids - for example trialkyl substituted acetic acid) in improving the resistance to hydrolysis of vinyl acetate and vinyl acrylic based latices was examined using several different monomer feed compositions. The long alkyl groups on the neo esters provide umbrella protection of the ester group and improve the hydrophobic behaviour of the coating. Samples were characterised for particle size minimum filming temperature and water absorption and were compared to typical commercial coating formulations for scrub resistance and external weathering performance. 4 refs. USA

Accession no. 868884 Item 361 Journal of Polymer Science: Polymer Physics Edition 40, No.17, 2002, p.1949 THERMAL LENSING IN POLY(VINYL ALCOHOL)/POLYANILINE BLENDS Pilla V; Catunda T; Balogh D T; Faria R M; Zilio S C Non-linear optical properties of polyvinyl alcohol (PVA)/polyaniline (PAni) blends are measured with the single-beam Z-scan technique with Fourier analysis. The results obtained with continuous wave (cw) excitation indicate that the self-phase modulation has a thermal origin. Besides the Z-scan technique the time-resolved

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mode-mismatched thermal lens (TL) technique employed to obtain the temperature coefficient of the optical path length ds/dT and the thermal diffusivity coefficient D for the specific concentrations used in our blends. ds/ dT varies between -0.8 and -1.0 x 10-4/K-1 whereas the thermal diffusivity varied between 1.0 and 1.3 x 10-3cm2. The TL technique is further used to study the ageing of the blends as they are heated to 90 deg.C. Unlike the electrical conductivity of PAni films which presents a strong dependence on the doping level the thermooptic properties present only a slight variation with doping. This feature indicates that the PVA/glutaraldehyde network made the main contribution to the thermooptic properties (D and ds/ dT) in the PAni blends. Similarly dimethyl sulphoxide as a solvent determined the thermooptic properties of PAni solutions. 24 refs. Sao PauloUniversity BRAZIL

Accession no. 866638 Item 362 Polymer International 51, No.8, 2002, p.715 GELATION OF A NEW HYDROGEL SYSTEM OF ATACTIC-POLY(VINYL ALCOHOL)/NACL/H2O Dai L; Ukai K; Shaheen S M; Yamaura K a-P/VA/NaCl/H2O hydrogels are prepared by gelation of aqueous atactic-polyvinyl alcohol (a-PVA) solutions in the presence of NaCl. The gelling temperature melt temperature and the preservation of water of the hydrogels are measured. The effect of the addition of NaCl to the hydrogels on gelling temperature and melting temperature is marked when the NaCl concentration is over a certain value. High NaCl concentration favours high-meltingpoint hydrogels. When the NaCl concentration is high enough (such as 11%) high-melting-point and white turbid opaque a-PVA/NaCl/H2O hydrogels can be prepared regardless of the PVA concentration. Similarly the low gelling temperature of a-PVA/NaCl/H2O solutions comes from low NaCl concentration while high gelling temperature ranges from 50 to 70 deg.C when the NaCl concentration is 11%. In appearance the types of syneresis of a-PVA/NaCl/H2O are X-type or a mixture of X- and n-types; water release of the hydrogels is slowed down by the addition of NaCl. 16 refs. Soochow University; Shinshu University CHINA; JAPAN

Accession no. 863757 Item 363 Polymer International 51, No.8, 2002, p.687 MOLECULAR SELECTIVITY OF TYROSINEIMPRINTED POLYMERS PREPARED BY SEED SWELLING AND SUSPENSION POLYMERISATION

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Zhang L; Cheng G; Fu C Tyrosine-imprinted microspheres are prepared in an aqueous system by seed swelling and suspension polymerisation using trimethylolpropane trimethacrylate (TRIM) acrylamide (AM) as well as methacrylic acid (MAA) linear polystyrene and toluene as crosslinker functional monomers seeds and porogens respectively. The size distribution proves to be greatly influenced by the ratio of water:TRIM (W/T) and the concentration of dispersant. When W/T is 46:1 (v/v) 4.6% (by mass) of poly(vinyl alcohol) (PVA) was used as dispersant the molar ratios of tyrosine MAA AM and TRIM are 1:8:8:17 the polymer beads have the better size monodispersity and the average size is 135 mu m while the sizes of the pores on the beads surfaces ranged from 1.25 to 9.0 μm. The adsorption behaviour and molecular selectivity of the beads are analysed using liquid chromatography; the results show that the adsorption behaviour of the beads follow the rule of Langmuir and the value of saturated absorption is 0.197 mmol g/1. The tyrosine-imprinted polymers exhibit an inherent selectivity for tyrosine; when phenylalanine is used as the competing molecule the separation factor alpha is up to 1.91. However the control polymers do not have this special molecule-selection capability and the relative separation factor beta is about 1.82 compared with the imprinted polymers. 21 refs. Tianjin University CHINA

Accession no. 863754 Item 364 Proceedings of Tech XXV, 25 Years of Tape Innovations.held Atlanta, GA 2002, p.83 FATE OF RESIDUAL SOLVENT IN DRYING COATINGS: CAN IT GET TRAPPED AND HOW? Cairncross R A A common goal in industrial drying of polymer solution coatings is to reduce the residual solvent content (RSC) to a specified level. Industrial dryers consist of a series of zones operated at different air temperatures and airflow rates to meet the RSC specifications and to produce defectfree coatings. A common observation is that when drying at a constant temperature the residual solvent content plateaus and the drying rate effectively drops to zero. Often the RSC can be reduced by further increasing the temperature. In homogeneous polymer solutions above the glass transition temperature of the polymer the observed plateau in RSC is accurately predicted by Fickian diffusion with a concentration-dependent diffusion coefficient. A simple model is developed which predicts the dependence of RSC on temperature coating thickness and the diffusion properties of the solution. In this case solvent is retained by the diffusional resistance to mass transfer and the diffusional resistance can be lowered by increasing temperature. However there are numerous claims that the RSC can also be reduced by using milder drying conditions



e.g. lowering airflow lowering temperature or partially saturating the air with solvent vapour. Such behaviour is anomalous and cannot be predicted by Fickian diffusion; this behaviour is termed anomalous skinning. Anomalous skinning in PMMA/acetone coatings is measured and a non-Fickian model is developed which predicts the anomalous behaviour. 23 refs. USA

Accession no. 863696 Item 365 Polymer Preprints 2001, 42, No.1, p.248 SYNTHESIS OF VINYLOXY ACETATE/ SILOXANE COPOLYMERS FOR USE ON E GLASS FIBERS Ma R P; Le-Huy C; Britcher L G; Matisons J G A vinyloxy acetate monomer was hydrosilated with triethoxysilane and applied to glass fibres where it condensed to form a siloxane polymer. The polymerised form of the vinyloxy acetate was also hydrosilated with a polysiloxane to form a polyvinyl acetate silicone and the hydrosilated products analysed by NMR spectroscopy. Surface characterisation of the glass fibres using DRIFT and SEM revealed that the silane acetate adsorbed strongly on the surface of the glass fibres. 3 refs. AUSTRALIA

Accession no. 862495 Item 366 Polymer Preprints 2002, 43, No.1, p.358 EFFECT OF ION-INCORPORATION ON SEGMENTAL ORIENTATION OF POLYMER CHAINS AND GUEST/HOST INTERACTIONS IN ORIENTED POLYMER/DYE SYSTEMS Pan B; Moore R B There has been much research focused on using polymers as matrices for dichroic polarisers which are often employed in thin-film-transistor liquid crystal displays (TFT LCD) sunglasses and spectroscopic instruments. These materials are typically semicrystalline polymers such as polyvinyl alcohol (PVA) and PE with incorporated dichroic chromophore. EVOH and is ionomer version carboxylated EVOH (EVOH-COOH) are employed as the host polymers for cationic dyes. The orientation of the dyes in the two polymers is correlated to the orientation of polymer chains. The dye uptake rates for EVOH and the sodium form carboxylated EVOH (EVOH-COONa) are determined and rationalised with respect to ionic effects. The incorporation of the ionic groups into EVOH enhances the orientation of the dye molecules although the segmental orientation of polymer chains is not influenced. This enhancement may be attributed to the ionic interactions between dye molecules and the ionic groups on polymer chains. The small amount of ionic groups also changes


the morphology of the polymer with a reduction in the crystallinity which results in higher dye uptake rate in carboxylated EVOH comparing to the pristine EVOH. 10 refs. USA

Accession no. 860867 Item 367 Iranian Polymer Journal 11, No.2, 2002, p.123 CROSS-LINKED POLY(VINYL ALCOHOL) HYDROGEL: STUDY OF SWELLING AND DRUG RELEASE BEHAVIOUR Varshosaz J; Koopaie N Crosslinked polyvinyl alcohol (PVA) is a prolongedrelease micromatrix a hydrophilic polymer and a potentially interesting hydrogel which is useful for drug delivery applications. As a part of drug development procedure the aim is to investigate the effect of structural changes on drug release (theophylline) from this polymeric network. The parameters studied include: crosslinking agent (glutaraldehyde) concentration PVA content of the films theophylline percentage and their overall effect on swelling of the hydrogels drug loading efficiency diffusion and release characteristics of theophylline from PVA films. Changes in glutaraldehyde percentage (or crosslink density) affect the swelling of the films. However increasing PVA percentage causes more swelling. Drug loading efficiency is higher in gels with higher glutaraldehyde PVA and theophylline percentages. Increasing contents of PVA and theophylline promote the diffusion coefficient and drug release rate but glutaraldehyde has a reverse effect. The pH does not affect the swelling and diffusion coefficient. Water transport and drug release mechanism predominantly follow a Fickian model. It may be concluded that by changing the PVA structural parameters a rate-controlled drug release is obtained. 23 refs. Isfahan University of Medical Sciences IRAN

Accession no. 860513 Item 368 Iranian Polymer Journal 11, No.2, 2002, p.93 OBSERVATION OF NEWTONIAN RINGS ON PVA POLYMER DURING HF LASER-INDUCED PHYSICAL MODIFICATION USING AN OPTICAL FIBRE Khosroshahi M E The ablation of polyvinyl alcohol (PVA) with a multiline 2.6-3.0 μm HF laser shows a strong interaction due to its relatively high absorption coefficient 7 x 104 cm-1 particularly hydrogen bands at 3597 cm-1. By using the expression heat diffusion limit surface temperature (Ts) of 340 K and 449 K are calculated for fluences of 0.3 and 1 J/cm2 respectively. The Ts values are well consistent with

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the PVA melting point of 531 K and SEM photographs. With the average activation energy of 188 kh/mol-1 and rate constant of 6 x 107/s a value of K=6 x 10-6/s for T=(146-230) K is obtained. The thermal degradation effect in short pulse duration is evident by Newtonian rings which basically is an interference pattern created by light reflects off the boiling ablated material and the solid material underneath. 18 refs. Tehran Amir Kabir University

and from the equilibrium water content (EWC). The DSC melting endotherms showed a sharp PVA peak 219.49 deg.C and the PVA/PDMS crosslinked networks had melting peaks close to this temperature. The EWC values were directly related to the PVA content of the crosslinked networks and were also dependent on temperature. 18 refs. Hanyang University; Chonbuk National University

IRAN


SOUTH KOREA

Accession no. 860510 Item 369 Adhesive Technology 19, No.3, 2002, p.24 AUTOMOTIVE BINDING TAPE A new PVOH binding tape for automotive thermal moulding techniques launched by Katco and Environmental Polymers is capable of perming at 190 deg.C which cuts moulding time and boosts productivity. Traditional cellulose tapes are not as strong as the PVOH tape as it cannot be used at above 160 deg.C and is likely to break when applied under stress. The new PVOH tape is also more thermally stable than existing forms. These old forms tend to expand at high temperatures which can result in parts being incorrectly formed says the company. Derek Hindson commercial director of Katco said 'an additional benefit of the new tape is that it leaves a glossy finish on the exterior of moulded rubber parts when the tape is removed. This gives parts a more professional and customer-friendly appearance and improves under-bonnet presentation.' The new PVOH automotive binding tapes are made from polymer pellets manufactured at Environmental Polymers' factory in Irlam near Manchester. This abstract includes all the information contained in the original article. Katco; Environmental Polymers Gropup Plc. EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE

Accession no. 859978 Item 370 Journal of Applied Polymer Science 85, No.5, 2002, p.957 SWOLLEN BEHAVIOR OF CROSSLINKED NETWORK HYDROGELS BASED ON POLY(VINYL ALCOHOL) AND POLYDIMETHYLSILOXANE A Mi-Seon Shin; Seon Jeong Kim; In Young Kim; Nam Gyun Kim; Chul Gyu Song; Sun I Kim 10 wt.% aqueous solution of polyvinyl alcohol (PVA) and a mixture of polydimethylsiloxane (PDMS) 1 wt.% 2, 2-dimethyl-2-phenylacetophenone and 0.5 mole% methylenebis acrylamide in isopropanol were prepared. The mixture was added to the PVA solution and heated at 90 deg.C over 7 hours. A number of crosslinked networks were obtained at 1:1 1:3 and 3:1 PVA/PDMS molar ratio and were characterised by FTIR DSC mechanical testing

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Item 371 Proceedings of GPEC 2002: Plastics Impact on the Environment held Detroit, MI 2002, p.369 RECENT ADVANCES IN THERMOPLASTICALLY-PROCESSABLE POLYVINYL ALCOHOL-BASED MATERIALS Cooper T A; Harrison P E; Wilkes T M PVOH has traditionally be usable or processable only in the form of aqueous solutions or films cast from these rather than as a thermoplastic. Recent advances in both PVOH formulating and processing technology are described which have resulted in the creation of a family of biodegradable and non-toxic PVOH-based materials to be produced for many thermoplastics applications using commercial melt processing methods without causing thermal or shear degradation. Examples are reviewed for biomedical waste management agricultural industrial and packaging applications which take advantage of uniquely advantageous PVOH properties in addition to its biodegradability. These properties are described. The products are claimed to represent viable environmentally advantageous alternatives to present non-degradable thermoplastics such as PE and PVC in which PVOH is stable during its intended use but which can be disposed of by dissolution and aqueous biodegradation composting incineration or recycling. 6 refs. EUROPEAN COMMUNITY; EUROPEAN UNION; UK; USA; WESTERN EUROPE

Accession no. 859626 Item 372 International Journal of Polymeric Materials 51, No.5, 2002, p.413 THIN FILM DOSIMETERS BASED ON ROSE BENGAL DYED POLY(VINYL ALCOHOL) Aabdel-Fattah A A; Hegazy E-S A; El-Ahdal M A; EzzEl-Din H Dyed polyvinyl alcohol (PVA) films are prepared by casting the aqueous solutions of PVA incorporating Rose Bengal (RB) dye with or without chloral hydrate on a horizontal glass plate. Such films are useful as routine highdose dosimeters. These flexible plastic film dosimeters are bleached when exposed to gamma-ray photons. The useful range of application of these films depends on the



concentration of chloral hydrate. RB/PVA film without chloral hydrate is suitable for application in the range of absorbed doses 10-150 kGy. The maximum range of RB/ PVA films containing chloral hydrate ranges from 5 to 20 kGy depending on and inversely proportional to chloral hydrate concentration in the film. The radiation-chemical yield (G-value) of films is calculated to be in the range from 0.272 to 10.3 mu mol/J where it increases with the increase of both RB and chloral hydrate concentration in the film. The effects of temperature and relative humidity during irradiation as well as pre- and post-irradiation storage on the radiation response of films are studied. Although the response of these films depends on relative humidity during irradiation they are highly stable for long times before and after irradiation when stored in dark and they are not affected by temperature that range from 0 to 45 deg.C during irradiation. 21 refs. Cairo National Center for Radiation Res.& Technol. EGYPT

Accession no. 858773 Item 373 Environmental Polymers Ltd, Manchester 2002, pp.6 ENVIRONMENTAL POLYMERS PIONEERING BIODEGRADABLE PLASTICS A general introduction to depart biodegradable nontoxic polymer products is presented. The material has been developed and commercialised by Environmental Polymers. The company has developed a patented process for extruding the PVOH pellets which can then be processed with minor modifications on existing equipment. The material is characterised by multidimensional strength and high puncture resistance. Its non-toxicity and gas barrier properties make it suitable for a wide range of food applications. It can also be used in multilayer applications. Environmental Polymers has developed the ability to customise the temperature at which depart dissolves which allows it to be used in a range of applications such as hospital laundry bags dosing pouches and additive sachets. EUROPEAN COMMUNITY; EUROPEAN UNION; UK; WESTERN EUROPE

Accession no. 858091 Item 374 Journal of Applied Polymer Science 84, No.14, 2002, p.2591 CHARACTERIZATION OF HYDROGELS BASED ON CHITOSAN AND COPOLYMER OF POLY(DIMETHYLSILOXANE) AND POLY(VINYL ALCOHOL) Mi-Seon Shin; Kim S I; In Young Kim; Nam Gyun Kim; Chul Gyu Song; Seon Jeong Kim Copolymers of polyvinyl alcohol (PVA) and PDMS were crosslinked with chitosan to produce semi-interpenetrating


polymer network hydrogels using UV irradiation. Photocrosslinked hydrogels had an equilibrium water content of 65-95%. The swelling behaviours of the hydrogels were studied by immersing the gels in various buffer solutions. The hydrogel with the highest chitosan weight ratio showed the highest equilibrium water content in time dependent and pH dependent swelling. These hydrogels may have potential biomedical applications. 19 refs. Korea Orthopedics & Rehabilitation Engineering Center; Hanyang University; Chonbuk National University KOREA

Accession no. 857068 Item 375 Polymer International 51, No.6, 2002, p.502 BENDING BEHAVIOUR OF ELECTRORESPONSIVE POLYVINYL ALCOHOL/POLYACRYLIC ACID SEMIINTERPENETRATING NETWORK HYDROGEL FIBRES UNDER AN ELECTRIC STIMULUS Fei J; Zhang Z; Gu L Polyvinyl alcohol (PVA) and polyacrylic acid (PAA) composite fibres are prepared via solution spinning and subsequently semi-interpenetrating networks (SIPN) are obtained by crosslinking the fibres with glutaraldehyde. The hydrogel fibres exhibit bending behaviour under DC electric stimulation. The effects of a number of factors are systematically studied including the PAA content within the network electric voltage imposed across the fibre the fibre diameter concentration of the crosslinking agent pH and ionic strength of the bath solution. Experimental results show a stable reversibility of bending behaviour under the applied electric field. The degree of bending at equilibrium and the bending speed of the hydrogel fibre increase with the intensity of the applied electric voltage and the PAA content having negatively charged ionic groups within the SIPN. The electroresponsive behaviour of the present SIPN hydrogel fibre is also affected by the aforementioned extrinsic factors. These observations are interpreted in terms of fibre stiffness fixed charge density and swelling pressure which depend on the hydrogel equilibrium states in different pH and ionic environments together with the electrochemical reactions under DC electric field. 35 refs. Shanghai Donghua University CHINA


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MISCIBILITY ENHANCEMENT ON THE IMMISCIBLE BINARY BLEND OF POLY(VINYL ACETATE) AND POLY(VINYL PYRROLIDONE) WITH BISPHENOL A Shiao-Wei Kuo; Shih-Chi Chan; Feng-Chih Chang The influence of additions of bisphenol A (BPA) on the miscibility of blends of poly(vinyl acetate) (PVAc) and poly(vinyl pyrrolidone) (PVP) was studied using differential scanning calorimetry and Fourier transform infrared spectroscopy (FTIR). Binary blends of BPA with PVAc and with PVP exhibited single glass transition temperatures (Tg) confirming miscibility over the entire compositional range. Hydrogen bonding between the hydroxyl group of BPA and the carbonyl group of PVAc and PVP was studied using FTIR. Enhanced miscibility of PVAc/PVP binary blends was observed with increasing BPA additions with a single Tg confirming full miscibility at sufficiently high additions. 40 refs. Taiwan National Chiao Tung University TAIWAN

Accession no. 856034 Item 377 Journal of Membrane Science 202, No.1-2, 2002, p.89 MEMBRANE OF PVA COATED ON POROUS CATALYTIC CERAMIC DISKS SUPPORTED H3PW12O40 Qing-Lin Liu; Qing-Biao Li

Ion-exchange membranes were obtained with semiinterpenetrating networks (s-IPN) by mixing filmforming polymer polyvinyl alcohol (PVA) for the crosslinked matrix and a polyelectrolyte to give the specific ion exchange property. The anionic polyelectrolytes used were: poly(sodium styrenesulphonate)(PSSNa) poly(styrenesulphonic acid)(PSS) polyacrylic acid (PAA) polyethyleneimine (PEI) poly(11-dimethyl35-dimethylenepiperidinium chloride)(PDDPCl) and poly(diallyldimethylammonium chloride)(PDDMACl) as cationic polyelectrolytes. Membranes containing 60% PVA and 40% polyelectrolyte showed the best compromise of mechanical properties homogeneity and ion-exchange properties. The crosslinking agent for the PVA network to promote efficient entrapment of the polyelectrolyte in the membrane was gaseous dibromoethane. The crosslinking time (tc) for each type of membrane was optimised and its effect was studied by thermogravimetric analysis and scanning electron microscopy. The best results i.e. high ion-exchange capacity combined with small swelling ratio were obtained with PVA/PAA and PVA/PSSNa/PSS membranes. Of the anion exchange membranes PVA/PEI gave the best permselectivity and the highest ion exchange capacity. 20 refs. Rouen University EUROPEAN COMMUNITY; EUROPEAN UNION; FRANCE; WESTERN EUROPE

Accession no. 853715 Item 379 JIS-K9550.

Catalytic discs of porous ceramic plate-supported H3PW12O40 were prepared. Crosslinked PVAl composite membranes using the catalytic discs as matrices were obtained by spin coating. The dehydration reaction of butanediol to form THF was used as a model reaction to demonstrate the catalytic activity of the disc and the latter was shown to be more effective than the original H3PW12O40. The separation properties of the membrane were also examined by pervaporation using the same reacting mixture and the water content in the reactor was much less than that of THF during the reaction coupled pervaporation. 13 refs.

POLYVINYL ALCOHOL

XiamenUniversity

Surface modification of many organic and inorganic substrates still represents a challenging problem. In particular there are only a few reactions allowing chemical modification of the surface of hydrophobic polymers such as polyolefins and fluoropolymers. It has recently been shown that polyvinyl alcohol (PVOH) possesses a unique property of adsorption on the surface of polytetrafluoroethyleneco-hexafluoropropylene (FEP) from aqueous solution. Such adsorption not only increases the surface energy of the substrate rendering it hydrophilic but also introduces hydroxyl groups to the surface that are readily reactive towards a range of surface modifying agents. This makes PVOH potentially a versatile tool for surface modification of many substrates. The adsorbed PVOH coatings are

CHINA

Accession no. 854753 Item 378 Journal of Applied Polymer Science 84, No.8, 2002, p.1572 ELABORATION OF ION-EXCHANGE MEMBRANES WITH SEMIINTERPENETRATING POLYMER NETWORKS CONTAINING POLY(VINYL ALCOHOL) AS POLYMER MATRIX Lebrun L; Da Silva E; Metayer M

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JAPAN

Accession no. 852709 Item 380 Polymer Preprints 2001, 42, No.2, p.328 ULTRA-THIN COATINGS OF POLYVINYL ALCOHOL DEPOSITED ON ORGANIC MONOLAYERS Kozlov M; McCarthy T J



presumably stabilised by intermolecular hydrogen bonds. It has long been known that adsorption of fully hydrolysed grades of PVOH at the air-water interface is accompanied by a gain in enthalpy (unlike most other water-soluble polymers) which is ascribed to formation of hydrogen bonds. Several organic monolayers are prepared by surface modification of silicone wafers and the adsorption of PVOH from aqueous solutions on these surfaces is studied. Deposition of PVOH on organic monolayers is found to be strongly dependent on the nature of the substrate and the solution conditions. PVOH coatings are formed preferably on more hydrophobic surfaces whereas hydrophilic substrates such as PEO-terminated monolayers do not support the formation of PVOH coatings. Salt content in the solution is shown to have a two-fold effect enhancing hydrophobic interactions and thus promoting adsorption but at the same time impeding aggregation of adsorbed polymer by means of hydrogen bonding. 7 refs.

Recent progress in theoretical and experimental studies has clarified many properties of glass transitions. However the mechanism of the glass transition has not yet been fully understood. The major problem to be achieved is the experimental approach to the investigation of the length scale of the glass transition and dynamics of the alphaprocess such as dynamical heterogeneity. For this purpose the glass transition in thin films of polymers especially PS has widely been investigated by using different experimental techniques and many interesting properties of the thin films have been observed. It is interesting to check whether the results extracted from the investigations on PS thin films hold also for other polymers. The dynamics of thin films of polyvinyl acetate and PMMA are investigated by dielectric relaxation spectroscopy in order to clarify this question. 6 refs. JAPAN


USA

Accession no. 849815 Item 381 Polymer Preprints 2001, 42, No.2, p.17 DYNAMICS OF POLYVINYL ACETATE-D3 ON SILICA O'Connor R D; Xu G; Blum F D

Item 383 Journal of Applied Polymer Science 83, No.2, 2002, p.244 SYNTHESIS OF GRAFT COPOLYMERIC MEMBRANES OF POLY(VINYL ALCOHOL) AND POLYACRYLAMIDE FOR THE PERVAPORATION SEPARATION OF WATER/ ACETIC ACID MIXTURES Aminabhavi T M; Naik H G

PVAc is an important polymer in applications due to both its bulk and surface characteristics. Its chain architecture gives it a low Tg and generally good qualities for processing and applications which include paints adhesives thin films and surface coatings. The surface dynamics of PVAc absorbed onto silica are investigated with 2H-NMR. For dynamics studies 2H-NMR is an excellent technique as it uses an innocuous probe that can report on correlation times (Tc) from approximately 10-8s to 10s. The use of two-dimensional exchange NMR (2D-X) and a side-chain methyl-d3 probe to investigate surface dynamics with Tcs in the range of 10-6 to over 1 s is reported. 2D-X NMR can be applied to very thin layers of polymers and yield information about polymer reorientation. More thorough analysis needs to be done to extract the motional note rates and angular excursion from this data. However it is clear from the spectra that the majority of surface PVAc species are much less mobile than in bulk. 4 refs.

Graft copolymers of polyvinyl alcohol with polyacrylamide were synthesised and then membranes were prepared at 48 and 93 percent grafting of acrylamide. These membranes were used in the pervaporation separation of water and acetic acid. The separation characteristics of the membranes were compared with neat PVA membrane at 25 35 and 45 degree C. The values of separation selectivity diffusion coefficient and permeation flux were calculated. These parameters were sensitive to the amount of water in the feed mixture. The highest separation selectivity value of 23 was observed for neat PVA at 25 degree C and the lowest value of 2.2 for 93 percent acrylamide grafted PVA. The temperature dependency of the permeation flux as well as diffusion followed an Arrhenius relationship. The grafted copolymer membranes were found to be effective in the selective separation of acetic acid from its aqueous mixture. 23 refs.

USA

INDIA



Item 382 Polymer Preprints 2001, 42, No.2, p.7 RELAXATION DYNAMICS IN THIN FILMS OF POLYVINYL ACETATE AND POLYMETHYL METHACRYLATE Fukao K; Uno S; Miyamoto Y; Hoshino A; Miyaji H

Item 384 Journal of Applied Polymer Science 82, No.1, 2001, p.143 PREPARATION OF POLYVINYL ALCOHOL HYDROGEL THROUGH THE SELECTIVE COMPLEXATION OF AMORPHOUS PHASE Hari P R; Sreenivasan K


Karnatak University

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A highly elastic polyvinyl alcohol (PVA) hydrogel film was prepared using a new simple and mild complexation reaction with phenyl boronic acid and its morphology mechanical properties and cytotoxicity were investigated. The changes in morphology and mechanical properties of PVA on complexation were determined by comparison with a reference sample of glutaraldehyde cross linked PVA film. The morphological changes were examined using differential scanning calorimetry (DSC) wide angle X-ray diffraction (WAXD) and scanning electron microscopy (SEM). DSC showed that the complexation reaction is confined in the amorphous region of the PVA. Investigation by WAXD showed that the PVA hydrogel film retains the inherent crystalline property of the semi-crystalline PVA. SEM found no change in the surface morphology of the PVA film resulting from this reaction. The PVA hydrogel film displays enhanced mechanical properties particularly in the wet condition resulting from its intact crystallinity. Also the inherent non-toxic characteristic property of PVA is unaffected by this complexation reaction. Consequently as the reaction can be performed under mild aqueous conditions and does not leave behind a toxic residue it may have very good potential in the biomedical and pharmaceutical fields. 12 refs. Sree Chitra Tirunal Inst.for Med.Sci.& Technology INDIA

Accession no. 844693 Item 385 Journal of Applied Polymer Science 82, No.1, 2001, p.136 SORPTION OF DYE WASTES BY POLY(VINYL ALCOHOL)/POLY(CARBOXYMETHYL CELLULOSE) BLEND GRAFTED THROUGH A RADIATION METHOD El-Salmawi K M; Abu Zaid M M; Ibraheim S M; ElNaggar A M; Zahran A H A polyvinyl alcohol (PVA)/CMC blend graft copolymer was used as a sorbent for dye wastes normally released from textile factories. The parameters that may affect the sorption process for example time temperature weight of the blend graft copolymer and volume of the dye waste were investigated. The PVA/CMC blend graft copolymer was prepared by radiation induced grafting of a styrene monomer on a PVA/CMC blend which improved its stability in water. The sorption of dyestuffs by the blend was determined by a method based upon spectrophotometric analysis. The blend graft copolymer has a high affinity for basic acid and reactive dyes. The sorption of dyes depends on the weight of the copolymer and not on the volume of the waste solution also it is more effective at 70C. The sorption of dyestuffs by a PVA/CMC graft copolymer could be used as a practical method to remove organic pollutants. 6 refs. Egypt National Centre for Radiation Res.& Technol.

Item 386 Macromolecules 34, No.22, 2001, p.7894 SPINODAL DECOMPOSITION AND SYNERESIS OF PVA GEL Takeshita H; Kanaya T; Nishida K; Kaji K Transparent gels of poly(vinyl alcohol) (PVA) were prepared by quenching a homogeneous solution of PVA in dimethyl sulphoxide/water (60:40) at 100 C to a temperature of -40 C. Phase separation was studied by measurements of UV transmittance time-resolved light scattering and volume changes. There was a single light scattering intensity peak which increased exponentially with time indicating spinodal decomposition. Domain growth was slowed in the later stages attributed to suppression of surface tension forces by the elastic force of the gel. Towards the end of the spinodal decomposition phase during shrinkage the UV transmittance gradually increased and the scattering intensity decreased corresponding to a relaxation process of internal fluctuations produced during spinodal decomposition. 36 refs. Kyoto University JAPAN

Accession no. 843608 Item 387 Polymer Journal (Japan) 33, No.8, 2001, p.610 SYNTHESIS OF POLY(VINYL ALCOHOL) GRAFT COPOLYMERS BY LIVING CATIONIC POLYMERIZATION IN THE PRESENCE OF ADDED BASES. PART 1. DESIGN AND SYNTHESIS OF POLY(VINYL ALCOHOL) GRAFT COPOLYMERS WITH WELL CONTROLLED POLY(VINYL ETHER)GRAFTS Aoshima S; Ikeda M; Nakayama K; Kobayashi E; Ohgi H; Sato T Partially hydrolysed polyvinyl acetate was employed as a new coupling agent for synthesising polyvinyl alcohol graft copolymers using living cationic polymerisation of vinyl ethers. Size exclusion chromatography was used to obtain the molecular weight distributions and nuclear magnetic resonance spectroscopy to determine the molecular structure of the graft copolymers. The resulting copolymers contained well controlled polyvinyl ether grafts with a narrow molecular weight distribution and good solubility. Graft copolymers with either polymethoxyethyl vinyl ether or polyethoxy vinyl ether chains exhibited thermosensitive phase separation in water. Full details of the synthesis and test results is given with detailed results discussion. 21 refs. Osaka University; Tokyo Science University; Kuraray Co.

EGYPT

JAPAN



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Item 388 Journal of Applied Polymer Science 82, No.13, 2001, p.3215 PREPARATION AND CHARACTERISATION OF POLYVINYL ALCOHOL-BASED MAGNETIC NANOCOMPOSITES. I. THERMAL AND MECHANICAL PROPERTIES Lopez D; Cendoya I; Torres F; Tejada J; Mijangos C CoFe2O4 magnetic nanoparticles are prepared by in situ precipitation and oxidation of Co2+ and Fe2+ within a sulphonated PS resin. The nanometric particles are characterised by X-ray diffraction. A ferrofluid is prepared from the CoFe2O4 mineralised polymer resin and water. Polyvinyl alcohol (PVA)-based nanocomposite materials are obtained by mixing different amounts of ferrofluid (compositions ranging within 0-51 wt.% of mineralised resin) with an aqueous solution of the polymer. The PVA composite materials are characterised by TGA DSC and stress-strain testing. The thermal and mechanical properties of PVA change with filler content exhibiting an initial increase in these properties due to polymer-filler interactions. After a maximum value at about 15 wt.% of mineralised resin the mechanical properties decrease probably due to particle aggregation which causes phase separation. The results obtained show that the nanoparticles are dispersed in the amorphous regions of the polymer the crystalline zones remaining unaltered up to compositions as high as 30 wt.%. 36 refs. CSIC; Barcelona University EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE

Accession no. 842144 Item 389 Journal of Applied Polymer Science 83, No.4, 2002, p.929 THERMAL AND MECHANICAL BEHAVIOURS OF POLYVINYL ALCOHOL-LACTOSE BLENDS Fan X-D; Hsieh Y-L; Krochta J M Thermal and mechanical behaviours of polyvinyl alcohol (PVA)-lactose blends are studied by differential scanning calorimetry thermogravimetric analysis and stress-strain analysis. The increase in glass transition temperature of the PVA lactose blends with lactose contents suggests the formation of hydrogen-bonded PVA lactose complex in the PVA matrix. The hydrogen bonding interactions can improve thermal and mechanical properties of the blends. Results of this study demonstrate that lactose a by-product of dairy industry can be used directly and in substantial quantity as a modifier to enforce the physical properties of PVA. 24 refs. Xian Northwestern Polytechnical University; California University CHINA; USA



Item 390 POLYVINYL ALCOHOL - DEVELOPMENTS Finch C A This book is the second edition of a book titled 'Polyvinyl alcohol: properties and applications' and the authors contributing to this present volume have all written with the understanding that the first volume will be available to the reader. The first group of chapters describe progress within particular topics described in the first book namely: general properties of the polymer; methods of preparation and hydrolysis; modifications by copolymerisation. Further chapters go on to discuss ethylene-vinyl copolymers chemical reactions and stereochemistry and applications. Applications discussed are relating to the following fields: textile sizing films paper manufacture adhesives binder reprography and photoresists. Each chapter is well referenced. PENTAFIN ASSOCIATES; CHICHESTER JOHN WILEY & SONS INC. 1992 PP.XX 850

Accession no. 841910 Item 391 Polymer 42, No.10, 2001, p.4687 TEMPERATURE DEPENDENCE OF THE MORPHOLOGY AND MECHANICAL PROPERTIES OF POLY(VINYL ALCOHOL) DRAWN FILMS PREPARED BY GELATION/ CRYSTALLIZATION FROM SOLUTIONS BY X-RAY AND SOLID STATE 13C NMR Matsuo M; Bin Y; Nakano M The morphology and mechanical properties of PVA were studied using atactic PVA (at-PVA) dry gel films prepared by crystallisation from solutions in dimethyl sulphoxide and water mixtures in which the Me2SO/water composition was set to be 60:40. The hot homogenised solution was quenched by pouring it into an aluminium tray at -80C thus generating a gel. The crystal lattice modulus along the chain axis was measured by XRD. The values were 200-220 GPa independent of temperature up to 170C. However the values became lower with further increase in temperature and the value at 200C was 133 GPa. This tendency differs from previous reports showing rapid decrease in the crystal modulus at higher temperature than 120C. The difference means that crystallites within the specimens prepared by quenching the solution at -80C are in much more stable state than those of the previous specimens. In spite of the temperature independence of the crystal modulus along the chain axis and the crystallinity the storage modulus similar to Young's modulus decreases gradually with increasing temperature. To study the mechanical properties and molecular orientation of the present specimens with the stable crystallites the orientational behaviour of crystallites was estimated in terms of the orientation distribution function of crystallites and Young's modulus was calculated by using the generalised orientation factors of crystallites and

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amorphous chain segments estimated from the orientation functions of crystallites and amorphous segments. In doing so the theoretical calculation was carried out by using a three-dimensional model in which the oriented crystalline layers are surrounded by an anisotropic amorphous phase and the strains of the two phases at the boundary are identical. The theoretical values were in good agreement with the experimental ones. The 13C-NMR measurements suggested that the intermolecular hydrogen bonds may be broken by drawing and the intramolecular hydrogen bonds are more preferably formed in the mm and mr sequences with draw ratio but no marked difference in the structure exists between the crystalline and noncrystalline regions as judged from the hydrogen bonding in the triad sequences. Even so the spin-lattice relaxation time decreased drastically with increasing temperature reflecting drastic activity of chain mobility. Accordingly the drastic decrease in Young's modulus (the storage modulus) is thought to be due to the fact that chain mobility in the amorphous phase becomes more pronounced as temperature increases. 49 refs. Nara Women's University Accession no. 841018 Item 392 Polymer Preprints 2000, 41, No.2, p.1685 ATTACHMENT OF PROTEINS TO POLYVINYL ALCOHOL FOR BIOMEDICAL APPLICATIONS Nuttelman C R; Anseth K S The ability to covalently attach proteins and other macromolecules to a polymer support material presents numerous advantages for a wide range of biomedical applications. For example attachment of water-soluble polymers such as polyethylene glycol and dextran can increase the solubility of the final macromolecular structure and their overall biocompatibility. The naturallyoccurring polysaccharide dextran has been used to transport anticancer drugs to turner sites in vivo and has been used as a stabiliser of enzymes and other proteins. Alternatively transport of macromolecules across cell membranes can be made more efficient by attaching them to polyethylene glycol. In addition polyethylene glycol can be used to prevent protein adsorption to surfaces. An attempt is made to covalently incorporate biologicallyactive macromolecules onto a polyvinyl alcohol (PVA) macromer that can be photopolymerised to form a hydrogel matrix. The abundant pendant hydroxyl groups on PVA can be modified to attach drugs adhesion peptides growth factors and other macromolecules to the polymer backbone. Depending upon the chemistry of the polymermacromolecule attachment a variety of unique responses can occur in a wide range of biomedical applications including tissue engineering and drug delivery. 5 refs. USA


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Item 393 Journal of Polymer Science: Polymer Chemistry Edition 39, No.20, 2001, p.3633 ROLE OF GRAFTING IN THE EMULSION POLYMERIZATION OF VINYL ACETATE WITH POLY(VINYLALCOHOL) AS AN EMULSIFIER. I. EFFECT OF THE DEGREE OF BLOCKINESS ON THE KINETICS AND MECHANISM OF GRAFTING Budhlall B M; Sudol E D; Dimonie V L; Klein A; ElAasser M S The role of grafting in particle nucleation during the emulsion polymerisation of vinyl acetate with partially hydrolysed polyvinyl alcohol (PVAl) as an emulsifier and potassium persulphate as an initiator was investigated. The polymerisations were carried out in batch with a low solids recipe. The kinetics of the emulsion polymerisations were measured using three medium molecular weight PVAls. The reaction kinetics particle number evolution and development of grafting were followed. Rates of polymerisation were found to be independent of the PVAl type. The particle nucleation was continuous and accompanied by extensive limited aggregation during the particle growth stages. The PVAls had different degrees of blockiness and the PVAl with a higher degree of blockiness led to nucleation and stabilisation of more particles. At higher conversions greater than 55% the total amount of grafted PVAc was independent of the degree of blockiness of the PVAl as seen by similar grafting efficiencies of PVAc for both PVAls. The largest amount of grafting of the PVAl stabiliser occurred early in the reactions contributing to the stabilisation of the particles. Further nucleation without measurable grafting indicates a homogeneous nucleation mechanism with absorption of aqueous phase PVAl and redistribution and previously adsorbed PVAl to particle stability. 24 refs. Lehigh University USA

Accession no. 836791 Item 394 Polymer Preprints 2000, 41, No.2, p.1580 EFFECT OF DEGREE OF SAPONIFICATION ON THE PHYSICOCHEMICAL PROPERTIES OF HIGH MOLECULAR WEIGHT SYNDIOTACTIC POLYVINYL ALCOHOL SOLUTION Lyoo W S; Choi J H The tacticity of a polymer has a profound influence on physical properties. Recently it was found that a polyvinyl pivalate (PVPi) of high syndiotactic diad (s-diad) content developed a well-oriented microfibrillar structure during saponification and gave rise to a fibrous PVA product. The in situ fibrillation during saponification was true only for PVPi which has high s-diad content but not feasible with polyvinyl acetate having relatively low s-diad



content suggesting that tacticity plays a significant role in the in situ fibrillation process together with an increase in rigidity of the polymer molecules by changing the chemical structure of the polymer from PVPi to PVA. In addition rheological characterisation of PVA solutions with different syndiotactic diad contents reveals that PVAs of s-diad content 63-65% gives rheological responses similar to the liquid crystalline polymer while those of 52-53% exhibit rheological properties typical of most flexible polymers. Among the molecular parameters of PVA including stereoregularity degree of saponification (DS) is quite a notable one because residual ester groups on side chains hinder hydrogen bonding interaction between the chains. As pivaloyl groups change into hydroxyl ones i.e. as DS increases during saponification highly crystalline and oriented PVA fibres are produced. Spontaneous orientation of polymer molecules during saponification of PVPi is traced considering DS of the polymer on rheological bases. 10 refs. KOREA



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Subject Index

Subject Index A (ATR-FTIR) SPECTROSCOPY, 35 AC IMPEDANCE SPECTROSCOPY, 61 ACID HYDROLYSIS, 79 ACRYLIC ESTER POLYMERS, 96 ACTIVE PACKAGING, 13 14 ADAM-GIBBS-SCHERER (AGS) MODELS, 32 ADEPT POLYMERS, 90 ADSORPTION, 80 AEROGELS, 36 AFM, 73 AG-PVA NANOCOMPOSITES, 48 ALCOHOLYSIS, 52 ALDOLASE, 97 ALOE VERA, 96 AMORPHOUS POLYMERS, 47 ANAEROBIC BIODEGRADATION TESTING, 20 ANOMALOUS SKINNING, 111 ATMOSPHERIC PRESSURE PLASMA TREATMENT, 101 ATOM TRANSFER RADICAL POLYMERISATION (ATRP), 25 ATOMIC FORCE MICROSCOPY (AFM), 62 ATOMIC FORCE MICROSCOPY HIGH RESOLUTION ELECTRON MICROSCOPY, 29 ATOM-TRANSFER RADICAL POLYMERISATION, 26 73 AUTOMOTIVE THERMAL MOULDING TECHNIQUES, 112 AZEOTROPIC MIXTURE, 77

B BIODEGRADABLE BONE SUBSTITUTES, 29 BIODEGRADABLE MATERIALS, 3 BIODEGRADABLE PACKAGING, 13 15 BIODEGRADABLE PLASTIC, 18 19 21 22 23 BIODEGRADABLE PLASTICS DISPOSAL, 20 BIODEGRADATION TEST, 109 BIOFILTER OPERATION, 76

BIOMINERALISATION, 105 BIOPOLYMERS, 14 15 19 21 BIOSENSOR APPLICATIONS, 57 BLOW MOULDING, 11 13

C CALORIMETRY, 59 CANCER THERAPY, 53 CAPROLACTONE HOMOPOLYMERISATION, 52 CARBON NANOTUBES (CNTS), 27 43 CARBOXYMETHYL POLYVINYL ALCOHOL (CMPVA), 28 CAST-HYBRID FILMS, 38 CELL CULTURE, 65 CELLULOSE BIOPOLYMERS, 16 CELLULOSE NANOFIBROUS MAT (CNM), 27 CEMENT MORTARS, 54 60 CHEMIRESISTORS, 103 CHITIN, 16 CHITOOLIGOSACCHARIDE, 91 CHITOSAN, 31 32 56 58 69 78 89 99 113 CHROMAMETER, 83 CHROMATOGRAPHY, 42 CLAY AEROGELS, 55 COATING AGENT, 26 COBALT MEDIATED RADICAL POLYMERISATION, 43 73 COLD-MIX ASPHALT (CMA), 57 COMPOSTABLE PLASTIC, 18 COMPOSTING, 22 CONONSOLVENCY, 98 CONTACT ANGLE MEASUREMENTS, 62 COOMASSIE BRILLIANT BLUE DYE, 80 COPOLYESTER ELASTOMER, 83 COPOLYMERISATION, 55 71 78 96 100 102 117 CORN STARCH ACETATES, 37 CRYOGELS, 78, 86 CRYSTALLISATION, 93 96 117 CUT-OUT FILTER, 95 CYCLIC VOLTAMMETRY (CV) ANALYSIS, 61 CYCLIC VOLTAMMETRY SCANNING ELECTRON MICROSCOPY, 82


D DEACETYLATION, 67 DEGRADABILITY, 18 DEGRADABLE PLASTIC, 18 DEGREE OF SAPONIFICATION (DS), 119 DESORPTION, 93 DIELECTRIC RELAXATION SPECTROSCOPY (DRS), 46 115 DIELECTRIC SPECTROSCOPY, 94 DIFFERENTIAL SCANNING CALORIMETER (DSC), 31 32 33 39 40 45 50 52 62 68 71 73 74 78 82 96 103 106 116 DIFFERENTIAL SCANNING CALORIMETRY TRANSMISSION ELECTRON MICROSCOPY, 36 DIFFERENTIAL THERMO GRAVIMETRY (DTG), 52 DYE SORPTION, 100 DYESTUFFS, 99 100 DYNAMIC MECHANICAL THERMAL ANALYSIS, 91 DYNAMIC-MECHANICAL THERMAL SPECTROSCOPY, 47

E ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY (EIS), 45 ELECTRON IRRADIATION, 30 ELECTRON SPIN RESONANCE, 104 ELECTROSPINNING, 10 31 55 57 60 65 67 75 78 82 84 91 100 ELLIPSOMETRY, 108 EMULSIFIER-FREE EMULSION POLYMERISATION, 71 EMULSION POLYMERISATION, 29 60 69 79 80 81 83 102 118 ENZYMATIC DEGRADATION, 97 ENZYME CELLULASE, 78 ENZYME IMMOBILISATION, 57 ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA) TECHNIQUES, 63 EXPLOSIVE PLASTICS, 95

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Subject Index

EXTRUSION, 8 11 12 EYRING’S VISCOSITY, 61

F FABRY-PEROT ETALON, 29 FE-SEM TEM SQUID MAGNETOMETRY, 25 FICKIAN DIFFUSION, 111 FIELD EMISSION SCANNING ELECTRON MICROSCOPY (FE-SEM), 38 91 FILM BLOWING, 8 11 13 FILM MOULDING, 12 FINEMAN-ROSS METHOD, 96 FLAME PLASMA SURFACE TREATMENT, 48 FOURIER TRANSFORM INFRARED RAMAN FLUORESCENCE, 54 FOURIER TRANSFORM INFRARED SECTROSCOPY, 28 29 31 33 35 38 39 45 52 58 62 63 68 72 73 75 78 84 86 89 103 106 114 FOURIER TRANSFORM INFRARED/ THERMOGRAVIMETRIC ANALYSIS (FTIR/TGA), 49 FOUR-PROBE TECHNIQUE, 82 FOX LAW, 52 FREE RADICAL POLYMERISATION, 26 41 69 85 FREEZE-THAW CYCLE, 56 59 72 81 86 FUEL CELL, 77 FUJII T, 26 FURUYA Y, 26

G GAMMA-CYCLODEXTRIN, 81 GAS CHROMATOGRAPHY, 26 GASEOUS PLASMA TREATMENT, 88 GEL, 92 99 GEL FORMATION, 64 GEL FRACTION, 72 GEL PERMEATION CHROMATOGRAPHY, 43 54 GEL SPINNING, 79 81 GEL SWELLING, 72 GELATIN, 16 76 77 85 98 109 110 117 GELS, 64 77 82 98 116 GLUTARALDEHYDE ACETALIZATION, 31

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GRAFT COPOLYMERISATION, 71 85 97 102 115 116 GRAFTING, 50 51 58 80 86 87 107 118 GRAVIMETRY, 101 GREEN POLYMER, 3

H HEAT-TREATMENT METHOD, 53 HOMOPOLYMERISATION, 25 HYBRID MATERIALS 51, 91 HYBRID POLYMERIC NETWORKS (HPN), 45 HYDRAULIC FRACTURING, 28 HYDROGEL, 13 14 27 28 32 36 38 39 43 45 53 56 57 59 60 61 63 66 71 72 72 78 78 79 81 82 84 86 89 92 94 96 97 100 101 103 106 110 111 113 115 HYDROGEN NUCLEAR MAGNETIC RESONANCE (1H NMR), 68 HYDROLASE, 7 8 9 10 11 17 25 30 51 54 58 59 77 79 89 90 97, 101 109 HYDROLYTICALLY DEGRADABLE PLASTIC, 18 HYDROPHILICITY, 85 99 HYDROXYAPATITE NANOFILLERS, 47 HYGROSCOPY, 10

I ICE SLURRIES, 61 INCINERATION, 22 INFRARED SPECTROSCOPY SWELLING, 40 INFRARED SPECTROSCOPY THERMAL ANALYSIS, 46 INJECTION MOULDING, 8 11 12 13 29 83 INTEGRATED PRODUCT POLICY (IPP) PROGRAMMES, 20 IR SPECTROSCOPY, 32 108 ISOTACTIC STAR-SHAPED POLY(VINYL ALCOHOL), 30

K KELEN-TUDOS METHODS, 96

L LANDFILLING, 23 LATEX PAINTS, 92 LATICES, 60 LIGNOCELLULOSES, 96 97 LIPASE IMMOBILIZATION, 63 LIPIDS, 16 LIVING CATIONIC POLYMERISATION, 54 116 LIVING RADICAL POLYMERISATION (LRP), 35

M MACROMOLECULAR DESIGN VIA THE INTERCHANGE OF XANTHATES (MADIX) PROCESS, 42 MACROPORES, 29 89 MADIX/RAFT POLYMERIZATION, 70 MAGNETIC POLY(VINYL ALCOHOL) (PVA) BEADS, 39 MAGNETOMETRY MEASUREMENTS, 84 MASS-SPECTROMETRY (MS), 46 MAXWELL-WAGNER THEORY, 64 MELT GRAFTING, 80 MELT MIXING, 87 MELT PROCESSING, 11 MELT SPINNING, 4 11 MERCAPTIDE THERMOLYSIS, 43 MERCURY DILATOMETRY, 32 METHANOL FUEL CELL APPLICATIONS, 45 METHYLENEBISACRYLAMIDE, 59 MICROSPHERES, 28 MINI-EMULSION COPOLYMERISATIONS, 27 86 87 MODIFIED MONTMORILLONITE (MMT), 63 64 MOISTURE SORPTION, 76 MOONEY VISCOSITY, 36 MORPHOLOGY, 50 51 54 55 56 59 65 70 71 75 82 90 91 93 98 104 106 111 116 117 MULCHING, 109 MULTI-JET ELECTROSPINNING, 91 MULTIWALL CARBON NANOTUBES (MWNTS), 27 70


Subject Index

N NANOCARBON MATERIALS, 25 26 NANOCLAY, 74 75 NANOFIBRE ELECTROSPINNING, 31 NANOG, 29 NEAR INFRARED SPECTROSCOPY (NIR), 52 NEWTONIAN RINGS, 112 NITROGEN PLASMA TREATMENT, 89 NMR, 33 49 52 55 71 84 111 NOAMI M, 26 NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY, 26 36 40 42 43 50 54 67 116

O ONE-PASS TEMPERATUREPROGRAMMED DESORPTION (OPTPD), 46 OSTWALD RIPENING, 61 OXIDATIVELY DEGRADABLE PLASTIC, 18 OXYGEN-SENSITIVE FILMS, 70

P PARALLELPLATE RHEOMETRY, 85 PHASE INVERSION TECHNIQUE, 98 PHENOL RESIN EMULSION, 75 PHOTOCURING, 92 PHOTODEGRADABLE PLASTIC, 18 20 PHOTOINDUCED LIVING RADICAL POLYMERIZATION, 26 PHOTOLUMINESCENCE (PL), 108 PLASTICIZER, 65 PMR SPECTROSCOPY, 101 POLARISING FILMS, 76 POLARIZED-LIGHT OPTICAL MICROSCOPY (POM), 50 POLY (VINYL ALCOHOL) APPLICATION, 4 POLY (VINYL ALCOHOL) MANUFACTURE, 6 POLYESTER (PES) SYSTEM, 39 82 POLYETHYLENE FILMS, 27 POLYMER EMULSION

ADHESIVES, 74 POLYMER HYDROPHOBIC, 67 POLYMER LATICES, 97 POLYMER MATRIX, 27 52 94 114 POLYMERISATION, 4 6 7 9 10 11 15 26 27 34 37 41 46 50 51 55 59 60 69 79 84 87 92 95 96 100 101 102 103 107 110 POLYPEPTIDES, 16 POLYSACCHARIDES, 16 POLYVINYL ACETATE EMULSION (PVAC-E), 57 POLYVINYL ALCOHOL BINDING TAPE, 89 POLYVINYL ALCOHOL FILMS, 34 POLYVINYL ALCOHOL HYDROGEL, 43 POSITRON ANNIHILATION, 30 POSITRON ANNIHILATION LIFETIME SPECTROSCOPY (PALS), 39 77 POTENTIOSTATIC METHOD, 61 PRECURSORS, 25 PVA COPOLYMER CAPSULES, 88 PVA CRYOGELS, 72 PVAL FILM PROPERTIES, 9 PVAL PROPERTIES, 11 PVAL/GELATIN BLENDS, 18 PVAL-STARCH BLENDS, 17 18 PYROLYSIS, 22 26 PYROLYSIS-GAS CHROMATOGRAPHY/ MASS SPECTROMETRIC ANALYSIS (PY-GC/MS), 49 PYRROLE, 82

R RADIATION METHOD, 116 RADICAL COPOLYMERISATION, 83 RADICAL POLYMERISATION, 27 42 RAFT POLYMERISATION, 42 RAMAN SPECTROSCOPY, 79 84 REDOX INITIATOR, 81 REFERENCES, 23 REPRESENTATIVE LIFE CYCLE ANALYSIS (LCA), 15 RESPONSE SURFACE METHODOLOGY (RSM), 68 REVERSIBLE ADDITIONFRAGMENTATION CHAIN TRANSFER (RAFT) POLYMERISATION, 37 RHEOLOGY, 59


RITEFLEX COPOLYESTER THERMOPLASTIC ELASTOMER, 83 ROSE BENGAL (RB) DYE, 112

S SAPONIFICATION, 41 46 72 90 118 119 SCANNING CALORIMETRY X-RAY DIFFRACTION, 31 SCANNING ELECTRON MICORSCOPY, 29 33 37 45 51 52 54 55 60 62 63 68 75 76 78 79 82 83 91 114 116 SCANNING PROBE MICROSCOPY, 67 SCANNING TRANSMISSION ELECTRON MICROSCOPY, 29 SEED SWELLING, 110 SEEDED EMULSION POLYMERISATIONS, 87 SEMI INTERPENETRATING NETWORKS (S-IPN), 113 114 SINGLE WALL CARBON NANOTUBES (SWNT), 79 SINGLE-BEAM Z-SCAN TECHNIQUE, 109 SINGLE-SCREW EXTRUDER, 41 74 SIZE EXCLUSION CHROMATOGRAPHY, 82 103 116 SMALL-ANGLE X-RAY SCATTERING (SAXS), 71 84 SOL-GEL PROCESS, 89 108 SOLID-STATE POLYMERIZATION METHOD, 71 SOLUTION COPOLYMERISATION, 90 SOLUTION PROCESSING, 10 SOLVENT CASTING METHOD, 66 SORPTION, 93 SOY PROTEIN ISOLATE (SPI), 48 SPECTROPHOTOMETRIC ANALYSIS, 116 STANELCO, 90 STERILISATION, 70 SULPHONATED POLYHEDRAL OLIGOSILSESQUIOXANE (SPOSS), 45 SURFACE MODIFICATION, 114 SUSPENSION POLYMERISATION, 110

123

Subject Index

SWELLING, 60 61 62 64 72 76 77 81 82 84 85 86 89 92 94 96 97 101 103 104 106 111 113 SWELLING RATIO (SR), 45 SWINE MANURE, 76 SYNDIOTACTICITY, 90 SYNTHETIC BIOPOLYMERS, 16 SYNTHETIC POLYMERS, 23

T TEM, 55 TENSILE STRESS-STRAIN MEASUREMENTS, 71 THERMAL ESTERIFICATION, 28 THERMAL GRAVIMETRY DIFFERENTIAL SCANNING CALORIMETRY, 82 THERMAL LENSING, 109 THERMAL MOULDING, 89 THERMALLY STIMULATED DEPOLARISATION CURRENTS (TSDCS), 46 66 THERMOFORMING, 11 THERMOGRAVIMETRIC ANALYSIS (TGA), 31 37 45 52 63 68 114 THERMOPLASTIC STARCH (TPS), 17 THIOPHENE SIDE-GROUPS, 82 TIMBER ENGINEERING, 106 TISSUE ENGINEERING, 38 58 118 TOMITA K, 26 TOOL-NARAYANASWAMYMOYNIHAN (TNM), 32 TRANSESTERIFICATION, 52 TRANSMISSION ELECTRON MICROSCOPY (TEM IMAGES), 36 40 52 53 94 TWIN-SCREW EXTRUDER, 74 TWO-STEP COMPOUNDING EXTRUSION PROCESS, 105 TWO-STEP SYNTHESIS, 27

V VAN DER WAALS BONDING FORCES, 48 VAPOUR PRESSURE OSMOMETRY, 103 VASCULAR EMBOLISATION, 56 VASCULAR GRAFTS, 25 VINYLON SPUN FIBRE, 4 VISCOSITY, 25

W WATER-SOLUBLE POLYMERS, 8 WET ADHESION, 92 WET SPINNING, 85 106 WET-CHEMICAL METHOD, 95 WHEAT GLUTEN, 36 WIDE ANGLE X-RAY DIFFRACTION (WAXD), 39 50 91 96 116

X XANTHATE INTERCHANGE REVERSIBLE ADDITION FRAGMENTATION POLYMERISATION, 77 XPS, 55 73 X-RAY DIFFRACTION (XRD), 25 29 46 47 58 60 63 66 78 91 X-RAY PHOTOELECTRON SPECTROSCOPIES, 33 39 53 54 72 75 79

Y YOUNG’S MODULUS, 27

Z ZONE DRAWING METHOD, 90 ZOSTERA FLAKES, 56 Z-SCAN TECHNIQUE, 80

U ULTRA VIOLET SPECTRAL ANALYSIS, 104 ULTRASONIC ENERGY, 81 ULTRATHIN POLYMERS, 48 UNSATURATED POLYESTER (UP) RESINS, 80 UTRAFINE HYDROGEL FIBRES, 82 UV RADIATION, 30 UV-VISIBLE SPECTROSCOPY, 25 78

124


Company Index

Company Index A AIST, 61 AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM),19 AMIRKABIR UNIVERSITY, 61 99 AMIRKABIR UNIVERSITY OF TECHNOLOGY, 41 AMIR KABIR UNIVERSITY OF TECHNOLOGY, 34 ANANTAPUR S.K.UNIVERSITY, 62 86 ANKARA MIDDLE EAST TECHNICAL UNIVERSITY, 82 ASACHI G.TECHNICAL UNIVERSITY, 105 ATHENS DEMOCRITOS NATIONAL RESEARCH CENTER, 86 ATHENS NATIONAL TECHNICAL UNIVERSITY, 47

B BARCELONA UNIVERSITY, 117 BARODA MS UNIVERSITY, 96 BASF AG, 52 BASILICATA UNIVERSITY, 109 BASQUE COUNTRY UNIVERSITY, 27 BAYREUTH UNIVERSITY, 82 BEIJING CHINESE ACADEMY OF SCIENCES, 39 BEIJING UNIVERSITY OF CHEMICAL TECHNOLOGY, 38 BEIJING UNIVERSITY OF SCIENCE & TECHNOLOGY, 39 BELARUS ACADEMY OF SCIENCES, 98 BELFAST QUEEN'S UNIVERSITY, 53 BELGRADE INSTITUTE OF NUCLEAR SCIENCES, 49 BHABHA ATOMIC RESEARCH CENTRE, 30 BOMBAY TEXTILE RESEARCH ASSN., 78 89 BORDEAUX 1 UNIVERSITE, 46 BRASOV TRANSILVANIA UNIVERSITY, 57

BRAZILINSTITUTO DE PESQUISAS ENERGETICAS E NUCLEARES, 63 BRIDGESTONE AMERICAS, 36 BRNO UNIVERSITY OF TECHNOLOGY, 47 BRUSSELS VRIJE UNIVERSITEIT, 34 45 BUCHAREST CHEMICAL RESEARCH INSTITUTE, 51 BUCHAREST POLYTECHNICAL UNIVERSITY, 51 BUENOS AIRES UNIVERSITY, 28 BULGARIAN ACADEMY OF SCIENCES, 95 B.V. CHINA, 38

C CAIRO AIN SHAMS UNIVERSITY, 90 CAIRO NATIONAL CENTER FOR RADIATION RES. & TECHNOL., 113 CAIRO UNIVERSITY, 42 90 CALIFORNIA UNIVERSITY, 117 CALIFORNIA UNIVERSITY AT DAVIS, 56 82 CANBERRA AUSTRALIAN NATIONAL UNIVERSITY, 108 CARBON NANOTECHNOLOGIES INC., 79 CARNEGIE-MELLON UNIVERSITY, 26 43 CASE WESTERN RESERVE UNIVERSITY, 35 36 46 CEA-SACLAY, 78 CELANESE EMULSIONS NORDEN AB, 92 CENTRAL ELECTROCHEMICAL RESEARCH INSTITUTE, 33 CENTRAL INSTITUTE OF PLASTICS ENGINEERING & TECHNOLOGY, 74 CHANGCHUN NORTHEAST NORMAL UNIVERSITY, 100 CHICHESTER JOHN WILEY & SONS INC., 117 CHINA NORTHEAST NORMAL UNIVERSITY, 55


CHINA UNIVERSITY OF SCIENCE & TECHNOLOGY, 81 CHINA WEST NORMAL UNIVERSITY, 53 CHINESE ACADEMY OF SCIENCES, 69 85 CHINESE ACADEMY OF TROPICAL AGRICULTURAL SCIENCES, 49 CHONBUK NATIONAL UNIVERSITY, 75 84 100 112 113 CHONNAM NATIONAL UNIVERSITY, 81 90 CHULALONGKORN UNIVERSITY, 104 CHUNG-HUA UNIVERSITY, 76 CHUNGNAM NATIONAL UNIVERSITY, 91 CHUNG YUAN CHRISTIAN UNIVERSITY, 103 CHUN-XIA ZHAO, 45 CLARKSON UNIVERSITY, 42 CLEVELAND LOUIS STOKES DVA MEDICAL CENTER, 35 COIMBRA UNIVERSITY, 57 89 96 COLORADO STATE UNIVERSITY, 93 COMMONWEALTH SCIENTIFIC & INDUSTRIAL RESEARCH ORGANISATION, 69 CONNECTICUT UNIVERSITY, 36 CSIC, 59 117 CSIRO MANUFACTURING AND INFRASTRUCTURE TECHNOLOGY, 88 CUZA AL.I. UNIVERSITY, 29 CUZA AL.I.UNIVERSITY, 105

D DAIDO CHEMICAL CORP., 88 DALIAN PLASTICS RESEARCH INSTITUTE CO.LTD., 46 DE-LONG WANG, 45 DE-YI WANG, 45 DONGHUA UNIVERSITY, 72

125

Company Index

E

G

ECOLE SUPERIEURE DE PHYSIQUE AND CHIMIE INDUSTRIELLES DE LA VILLE DE PARIS, 47 EGYPTIAN PETROLEUM RESEARCH INSTITUTE, 97 EGYPT NATIONAL CENTRE FOR RADIATION RES.& TECHNOL., 64 100 116 EGYPT NATIONAL RESEARCH CENTRE, 69 EINDHOVEN UNIVERSITY OF TECHNOLOGY, 62 ELSEVIER LTD, 31 50 68 ELSEVIER LTD., 55 ENVIRONMENTAL POLYMERS GROPUP PLC., 112 ETH ZURICH, 70 EUROPEAN COMMUNITY, 30 33 34 37 38 40 42 43 45 46 47 51 52 53 54 57 58 59 60 62 68 70 72 73 75 77 78 79 80 82 83 86 89 90 92 94 97 98 100 103 104 105 106 107 109 112 113 114 117 EUROPEAN ECONOMIC COMMUNITY, 34 42 45 EUROPEAN UNION, 12 30 33 34 37 38 40 42 43 45 46 47 51 52 53 54 57 58 59 60 62 68 70 72 73 75 77 78 79 80 82 83 86 89 90 92 94 97 98 100 103 104 105 106 107 109 112 113 114 117 EUROPEAN UNION LANDFILL DIRECTIVE, 23 EUROPEAN UNION LEGISLATION, 20 23

GEORGETOWN UNIVERSITY, 39 GEORGIA INSTITUTE OF TECHNOLOGY, 37 79 GRANADA UNIVERSITY, 70 GRENOBLE INSTITUT NATIONAL POLYTECHNIQUE, 30 GUANGXI UNIVERSITY, 32 GUILIN UNIVERSITY OF TECHNOLOGY, 73 GUNG UNIVERSITY, 31 GYEONGSANG NATIONAL UNIVERSITY, 77

F FEDERATION DES POLYMERISTES LYONNAIS, 52 FIAT RESEARCH CENTER, 43 FLYNN BURNER CORP., 48 FOREST RESEARCH INSTITUTE OF MALAYSIA, 69 FRANCHE-COMTE UNIVERSITE, 94 FRAUNHOFER INSTITUTE FOR APPLIED POLYMER RESEARCH, 104 FUJIAN NORMAL UNIVERSITY, 27 FUZHOU UNIVERSITY, 44

126

H HACETTEPEUNIVERSITY, 53 HANGYANG UNIVERSITY, 87 HANNAM UNIVERSITY, 77 88 HANYANG UNIVERSITY, 46 51 62 77 85 88 94 103 106 112 113 HEBEI UNIVERSITY, 102 107 HEFEI UNIVERSITY OF TECHNOLOGY, 58 HEILONGJIANG UNIVERSITY, 55 HELSINKI UNIVERSITY OF TECHNOLOGY, 53 HEXI UNIVERSITY, 52 HONG KONG POLYTECHNIC UNIVERSITY, 38 HUAQIAO UNIVERSITY, 27 HYDERABAD CENTRE FOR CELLULAR AND MOLECULAR BIOLOGY, 81 HYDERABAD UNIVERSITY, 81

I IDAHO NATIONAL LABORATORY, 28 INDIA CENTRAL FOOD TECHNOLOGICAL RESEARCH INST., 76 INDIA CENTRAL SALT & MARINE CHEM.RES.INST., 87 INDIAN INSTITUTE OF CHEMICAL TECHNOLOGY, 44 64 INDIAN INSTITUTE OF SCIENCE, 33 86 INDIAN INSTITUTE OF TECHNOLOGY, 33 67 80 INDIAN PETROCHEMICAL CORP.LTD., 96

INHA UNIVERSITY, 30 51 62 INNOVATION GROUP, 55 INSTITUTO DI RICERCA E TECNOLOGIA DELLE MATERIE PLASTICHE, 109 INTERCHEM HELLAS SA, 92 IOWA STATE UNIVERSITY, 105 IRANIAN RESEARCH ORGANIZATION OF SCIENCE & TECHNOLOGY, 69 IRAN POLYMER & PETROCHEMICAL INSTITUTE, 41 ISFAHAN UNIVERSITY OF MEDICAL SCIENCES, 111 ISTANBUL TECHNICAL UNIVERSITY, 63 82 ITAJUBA UNIVERSIDADE FEDERAL, 63 ITALY NATIONAL RESEARCH COUNCIL, 109 IVERSITY, 58

J JABALPUR GOVERNMENT AUTONOMOUS SCIENCE COLLEGE, 78 JAPAN ADVANCED INSTITUTE OF SCIENCE & TECHNOLOGY, 44 JAPAN ATOMIC ENERGY AGENCY, 40 JAPANESE STANDARDS ASSOCIATION, 98 JAPAN NATIONAL INSTITUTES OF NATURAL SCIENCES, 29 JASSY, 105 JASSY CUZA AL.I. UNIVERSITY, 34 JILIN UNIVERSITY, 72 JIMEI MIDDLE SCHOOL, 55

K KANSAS STATE UNIVERSITY, 99 KARNATAK UNIVERSITY, 115 KASHAN UNIVERSITY, 61 KATCO, 112 KERALA UNIVERSITY, 80 KERMANSHAH UNIVERSITY OF MEDICAL SCIENCES, 98 KHARAGPUR INDIAN INSTITUTE OF TECHNOLOGY, 76


Company Index

KIEV INSTITUTE OF PHYSICAL CHEMISTRY, 78 KOLON INDUSTRIES INC., 81 KOREA ATOMIC ENERGY RESEARCH INSTITUTE, 92 96 KOREA INSTITUTE OF CERAMIC ENGINEERING & TECHNOLOGY, 96 KOREA INSTITUTE OF FOOTWEAR & LEATHER TECHNOLOGY, 54 KOREA ORTHOPEDICS & REHABILITATION ENGINEERING CENTER, 113 KURARAY CO.LTD, 49 70 116 KUVEMPU UNIVERSITY, 32 KYOTO INSTITUTE OF TECHNOLOGY, 41 KYOTOINSTITUTE OF TECHNOLOGY, 71 KYOTO UNIVERSITY, 40 49 65 70 85 98 116 KYUNG HEE UNIVERSITY, 91 KYUNGIL UNIVERSITY, 60 KYUNGPOOK NATIONAL UNIVERSITY, 62 87 90

L LANZHOU NORTHWEST NORMAL UNIVERSITY, 73 LANZHOU UNIVERSITY, 52 LARISSA TECHNOLOGICAL EDUCATIONAL INSTITUTE, 58 LAUSANNE ECOLE POLYTECHNIQUE FEDERALE, 44 LEHIGH UNIVERSITY, 87 118 LG CHEM, 77 LIEGE UNIVERSITY, 42 73 LJUBLJANA UNIVERSITY, 89 LOMONOSOV M.V.ACADEMY OF FINE CHEMICAL TECHNOLOGY, 74 91 LONDON IMPERIAL COLLEGE OF SCIENCE TECHNOLOGY & MEDICINE, 37 LONDON UNIVERSITY KING'S COLLEGE, 73 LOWELL MASSACHUSETTS UNIVERSITY, 29 LUBBOCK TEXAS TECH UNIVERSITY, 47 LUBLIN MARIA CURIE-SKLODOWSKA UNIVERSITY, 47

M MACPLAS INTERNATIONAL, 89 MADISON UNIVERSITY OF WISCONSIN, 61 MADRID INSTITUTO DE CIENCIA Y TEC.DE POLIM, 77 MADRID INSTITUTO DE CIENCIA Y TEC.DE POLIM., 79 MANCHESTER UNIVERSITY, 37 MANGALORE UNIVERSITY, 30 66 MANSOURA UNIVERSITY, 104 MAPEI SPA, 80 MARBURG PHILIPPS UNIVERSITAT, 105 MARBURG PHILIPPS UNIVERSITY, 83 MARINGA UNIVERSIDADE ESTADUAL, 28 68 MARYLAND UNIVERSITY, 37 MASSACHUSETTS GENERAL HOSPITAL, 39 MASSACHUSETTS LAHEY CLINIC MEDICAL CENTER, 29 MERSIN UNIVERSITY, 89 MICHOACANA UNIVERSIDAD, 57 MIE UNIVERSITY, 83 MILANO POLITECNICO, 80 MINAS GERAISFUNDACAO EZEQUIEL DIAS, 63 MINAS GERAIS UNIVERSIDADE FEDERAL, 39 84 MINAS GERAISUNIVERSIDADE FEDERAL, 63 MINGCHI UNIVERSITY OF TECHNOLOGY, 61 MINNESOTA UNIVERSITY, 107 MOKPO NATIONAL UNIVERSITY, 96 MONTERREY INSTITUTO TECNOLOGICO Y DE ESTUDIOS SUPERIORES, 57 MONTREAL ECOLE POLYTECHNIQUE, 84 MONTREAL UNIVERSITY, 25 84 MOSCOW INSTITUTE OF CHEMICAL PHYSICS, 96 MOUNT HOLYOKE COLLEGE, 53 MULHOUSE ECOLE NATIONALE SUPERIEURE DE CHIMIE, 92 MUMBAI UNIVERSITY, 93


MUMBAI UNIVERSITY INSTITUTE OF CHEMICAL TECHNOLOGY, 64 MUMBAI WATUMULL INSTITUTE OF TECHNOLOGY, 64 MYSORE UNIVERSITY, 32

N NAGOYA UNIVERSITY, 26 91 NANJING UNIVERSITY, 25 NAPAAM TEZPUR UNIVERSITY, 89 NAPLES INSTITUTE OF COMPOSITE & BIOMEDICAL MATERIALS, 43 NAPOLI UNIVERSITA FEDERICO II, 43 NARA INSTITUTE OF SCIENCE & TECHNOLOGY, 91 NARA WOMEN'S UNIVERSITY, 58 70 118 NEW BRUNSWICK UNIVERSITY, 36 NEW SOUTH WALES UNIVERSITY, 70 77 NISSHIN KASEI CO.LTD., 88 NITTO DENKO CORP., 41 71 NORTH CAROLINA STATE UNIVERSITY, 44 82 101 NORTH CHINA INSTITUTE OF TECHNOLOGY POLYMER, 71 NORTHERN IRELAND DEPARTMENT OF AGRICULTURE, 53 NRCS DEMOKRITOS, 57

O OKAYAMA UNIVERSITY, 97 OSAKA INSTITUTE OF TECHNOLOGY, 46 OSAKA UNIVERSITY, 116

P PAIS VASCO UNIVERSIDAD, 40 PALAISEAU ECOLE POLYTECHNIQUE, 42 PARDUBICE UNIVERSITY, 32 PARIS VII UNIVERSITE, 25 PARIS XIII UNIVERSITE, 25 PAULISTA UNIVERSIDADE ESTADUAL, 68

127

Company Index

PENNSYLVANIA STATE UNIVERSITY, 26 PENNSYLVANIA UNIVERSITY, 35 PENTAFIN ASSOCIATES, 117 PERNAMBUCO UNIVERSIDADE FEDERAL, 94 PETRO CHINA CO.LTD., 72 PHARMACEUTICAL TECHNOLOGY, 26 PHARMACEUTICAL TECHNOLOGY EUROPE, 88 PISA UNIVERSITY, 59 68 97 109 PRECISION CUSTOM COATING, 83 PREFECTURE UNIVERSITY, 51 PRETORIA UNIVERSITY, 31 PUNE NATIONAL CHEMICAL LABORATORY, 85 PUSAN NATIONAL UNIVERSITY, 38 54 59 PUTRA MALAYSIA UNIVERSITI, 69 PVAXX RESEARCH & DEVELOPMENT LTD, 12

Q QINGDAO OCEAN UNIVERSITY, 28 43 QINGDAO UNIVERSITY, 28 QUEBEC UNIVERSITE A TROIS-RIVIERES, 94

R RANDOX LABORATORIES LTD., 78 RANI DURGAVATI UNIVERSITY, 66 RAZI UNIVERSITY, 98 RHODIA TECHNICAL AND RESEARCH CENTRE, 42 RIO DE JANEIRO CIDADE UNIVERSITARIA, 56 RIO DE JANEIRO UNIVERSIDADE FEDERAL, 39 56 RIO GRANDE DO SUL UNIVERSIDADE FEDERAL, 45 ROUEN UNIVERSITY, 114 RUSSIAN ACADEMY OF SCIENCES, 74 91

128

S SALERNO UNIVERSITY, 75 SANTA CATARINA FEDERAL UNIVERSITY, 41 SAO CARLOS UNIVERSIDADE FEDERAL, 39 108 SAO PAULO UNIVERSITY, 63 SAO PAULOUNIVERSITY, 110 SCANDINAVIA, 43 SCHULMAN A. INC., 83 SCIENCE MUSEUM, 12 SEOUL NATIONAL UNIVERSITY, 35 91 92 93 94 SHANGHAI DONGHUA UNIVERSITY, 33 38 101 113 SHANGHAI INSTITUTE OF CERAMICS, 89 SHANGHAI JIAO TONG UNIVERSITY, 27 SHANXI UNIVERSITY, 37 SHIGA PREFECTURE UNIVERSITY, 29 50 102 SHIGA PREFECTURE UNIVERSITY, 31 SHINSHU UNIVERSITY, 91 101 106 110 SHIONOGI AND CO.LTD., 26 SHIRATORI NANOTECHNOLOGY CO.LTD., 91 SICHUAN UNIVERSITY, 33 39 45 71 SICHUAN VINYLON WORKS, 85 SINGAPORE NATIONAL UNIVERSITY, 74 80 SINOPEC, 85 SOFIA INSTITUTE OF POLYMERS, 47 SOLVAY RESEARCH & TECHNOLOGY, 42 73 SOOCHOW UNIVERSITY, 110 SOUTH AUSTRALIA UNIVERSITY, 49 SOUTH CHINA UNIVERSITY OF TECHNOLOGY, 25 36 41 76 SOUTH PACIFIC UNIVERSITY, 53 SREE CHITRA TIRUNAL INST.FOR MED.SCI.& TECHNOLOGY, 116 SRI CONSULTING, 49 SRI VENKATESWARA UNIVERSITY, 44 47 64 86 STANELCO PRODUCTS LTD., 90

ST.ETIENNE UNIVERSITE JEAN MONNET, 52 SUEZ CANAL UNIVERSITY, 40 90 95 SUNGSHIN WOMEN'S UNIVERSITY, 88 SUN YAT-SEN UNIVERSITY, 63 74 SWINBURNE UNIVERSITY OF TECHNOLOGY, 92 SZCZECIN UNIVERSITY OF TECHNOLOGY, 51

T TAIPEI MING CHI UNIVERSITY OF TECHNOLOGY, 31 TAIWAN FENG CHIA UNIVERSITY, 37 69 TAIWAN NATIONAL CHENG KUNG UNIVERSITY, 50 TAIWAN NATIONAL CHIAO TUNG UNIVERSITY, 25 114 TAIWAN NATIONAL CHUNGHSING UNIVERSITY, 44 76 TARBIAT MODARRES UNIVERSITY, 26 98 101 TARRAGONA UNIVERSITAT ROVIRA I VIRGILI, 103 TATUNG UNIVERSITY, 107 TECHNOLOGY, SZCZECIN UNIVERSITY OF, 51 TEHRAN AMIR KABIR UNIVERSITY, 58 112 TEHRAN UNIVERSITY, 30 71 TEHRAN UNIVERSITY OF MEDICAL SCIENCE, 99 TEXAS TECHNICAL UNIVERSITY, 48 TEXASUNIVERSITY, 53 THESSALONIKI ARISTOTLE UNIVERSITY, 58 TIANJIN HOSPITAL, 65 TIANJIN INSTITUTE OF MEDICAL EQUIPMENT, 66 TIANJIN POLYTECHNIC UNIVERSITY, 31 36 66 73 TIANJIN UNIVERSITY, 50 57 61 65 72 75 77 78 110 TIANJIN UNIVERSITY OF COMMERCE, 48 TICONA CORP., 83 TNO SCIENCE AND INDUSTRY, 62 TOHOKU UNIVERSITY, 29 TOKO UNIVERSITY, 37 TOKYO INSTITUTE OF TECHNOLOGY, 67


Company Index

TOKYO SCIENCE UNIVERSITY, 116 TOKYO UNIVERSITY, 52 TOKYO UNIVERSITY OF AGRICULTURE & TECHNOLOGY, 85 TONGJI UNIVERSITY, 108 TSING HUA UNIVERSITY, 93 TURKEY NIGDE UNIVERSITY, 82 TWENTE UNIVERSITY, 51

U UBE NATIONAL COLLEGE OF TECHNOLOGY, 109 UKRAINE INSTITUTE OF PHYSICS, 47 78 UKRAINE INSTITUTE OF SURFACE CHEMISTRY, 47 ULSTER UNIVERSITY, 89 UNIVERSITY OF TECHNOLOGY, 65 UNIVERSITY OF WARWICK'S, 12 UPPSALA UNIVERSITY, 43 72 US DEPT. OF AGRICULTURE, 68 97 US NAVAL RESEARCH LABORATORY, 36

Y YA LIU, 45 YAMAGATA UNIVERSITY, 40 YAMAGUCHI UNIVERSITY, 109 YEUNGNAM UNIVERSITY, 60 62 73 81 83 84 87 90 YOKOHAMA KEIO UNIVERSITY, 91 YONSEI UNIVERSITY, 30 YUCATAN CENTRO DE INVESTIGACION Y ESTUDIOS AVANZADOS DEL IPN, 57 YU-RONG MOU, 45 YU-ZHONG WANG, 45

Z ZAGAZIG UNIVERSITY, 95 ZHEJIANG UNIVERSITY, 44 86 94 ZHI-CHAO LAI SHANXIUNIVERSITY, 37

W WALES UNIVERSITY, 53 WARSAW UNIVERSITY, 51 WARWICK MANUFACTURING GROUP, 12 WATERLOO UNIVERSITY, 63 WEIZMANN INSTITUTE OF SCIENCE, 86 WESTERN EUROPE-GENERAL, 54 WISCONSIN-MADISON UNIVERSITY, 29 89 WUHAN UNIVERSITY, 32 38 78 100 WUHAN UNIVERSITY OF TECHNOLOGY, 32

X XIAMENUNIVERSITY, 114 XIAN JIAOTONG UNIVERSITY, 108 XIAN NORTHWESTERN POLYTECHNICAL UNIVERSITY, 117


129

Company Index

130


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Engineering and Structural Adhesives (Rapra Review Reports) (Vol 15,No.1)

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Polyvinyl Alcohol: Materials, Processing and Applications (Rapra Review Reports)

Rigid Plastics Packaging - Materials, Processes and Applications (Rapra Review Reports)

Silicone Elastomers (Rapra Review Reports)

Radiation Curing (Rapra Review Reports)

Adhesion to Fluoropolymers: Rapra Review Report 183 (Rapra Review Reports)

Multi-Material Injection Moulding (Rapra Review Reports)

Polymer Processing with Supercritical Fluids (Rapra Review Reports)

Analysis of Plastics (Rapra Review Reports)

Developments in Thermoplastic Elastomers (Rapra review reports)

Rubber Product Failure (Rapra Review Reports)

Polymers in Aerospace Applications (Rapra Review Reports, Report 192)

Mixing of Vulcanisable Rubbers and Thermoplastic Elastomers: Rapra Review Report 178 (Rapra Review Reports)

Mould Sticking, Fouling and Cleaning (Rapra Review Reports)

Adhesion and Bonding to Polyolefins (Rapra Review Reports)

EU Regulation of Chemicals REACH: Rapra Review Report 181 (Rapra Review Reports)

Analysis of Thermoset Materials, Precursors and Products (Rapra review reports) (v. 14, No. 6)

Advances in Automation for Plastics Injection Moulding (Rapra Review Reports)

In-Mould Decoration of Plastics (Rapra Review Reports)

Tyre Compounding for Improved Performance (Rapra Review Reports)

Developments in Colorants for Plastics (Rapra Review Reports)

Blowing Agents for Polyurethane Foams (Rapra Review Reports)

Emulsion Polymerisation and Latex Applications (Rapra Review Reports) (v. 14, No. 4)

NANOSTRUCTURED MATERIALS Processing Properties and Potential Applications

Biocides in Plastics: Rapra Review Report 180

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Adhesives Technology for Electronic Applications, Second Edition: Materials, Processing, Reliability (Materials and Processes for Electronic Applications)

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