The Effect of UV Light and Weather, Second Edition: On Plastics and Elastomers, 2nd Edition

The Effects of UV Light and Weather on Plastics and Elastomers Second Edition Liesl K. Massey Copyright © 2007 by W...

Author: Liesl K. Massey

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The Effects of

UV Light and Weather on Plastics and Elastomers Second Edition

Liesl K. Massey

Copyright © 2007 by William Andrew, Inc. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the Publisher. Plastics Design Library and its logo are owned by William Andrew, Inc. Library of Congress Cataloging-in-Publication Data Massey, Liesl K. The effects of UV light and weather on plastics and elastomers / Liesl K. Massey. -- 2nd ed. p. cm. Includes bibliographical references and index. ISBN-13: 978-0-8155-1525-8 (978-0-8155) ISBN-10: 0-8155-1525-1 (0-8155) 1. Plastics--Effect of radiation on. 2. Elastomers--Effect of radiation on. I. Title. TA455.P5M34355 2007 620.1'9232--dc22 2006018850

Printed in the United States of America This book is printed on acid-free paper. 10 9 8 7 6 5 4 3 2 1 Published by: William Andrew Publishing 13 Eaton Avenue Norwich, NY 13815 1-800-932-7045 www.williamandrew.com

NOTICE To the best of our knowledge the information in this publication is accurate; however the Publisher does not assume any responsibility or liability for the accuracy or completeness of, or consequences arising from, such information. This book is intended for informational purposes only. Mention of trade names or commercial products does not constitute endorsement or recommendation for their use by the Publisher. Final determination of the suitability of any information or product for any use, and the manner of that use, is the sole responsibility of the user. Anyone intending to rely upon any recommendation of materials or procedures mentioned in this publication should be independently satisfied as to such suitability, and must meet all applicable safety and health standards.

“To nourish children and raise them against odds is in any time, any place, more valuable than to fix bolts in cars or design nuclear weapons.” Marilyn French I dedicate this book to the wonderful man who has allowed me to realize this to be true.

William Andrew Publishing

Sina Ebnesajjad, Editor in Chief (External Scientific Advisor)

Table of Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv List of Graphs and Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 How to Use This Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weatherability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weather Defined . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Variations in Natural Weathering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Testing for Weatherability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elements of Weather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wavelength Regions of UV Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Moisture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Radiation and Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Radiation and Oxygen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Reducing the Effect of Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Surface Temperature and Thermal Degradation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties Post-Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UV Additives and Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UV Absorbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hindered Amine Light Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Antioxidants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UV Inhibitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 1 1 1 1 2 2 2 3 3 3 3 4 4 5 6 6 6 6

Test Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Indoor and Interior Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Outdoor Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Accelerated Outdoor Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Conventional Aging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Conventional Aging with Spray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Humidity Variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Solar Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Sample Mounting Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Artificial Accelerated Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Conditions for Reproducing Natural Weathering Stresses in the Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Xenon Arc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Fluorescent or QUV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Carbon Arc or Fadeometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Notes on Variability in Testing and Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Color Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

vi

The Effects of UV Light and Weather on Plastics and Elastomers

Thermoplastics ABS Acrylonitrile-Butadiene-Styrene—Chapter 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Acrylonitrile-Styrene-Acrylate/Acrylonitrile-Butadiene-Styrene Capstock—Chapter 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Acetal Acetal—Chapter 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Weathering Properties: General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Colored Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Unpigmented Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Elevated Air Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

35 35 36 36 37

Acrylonitrile-Styrene-Acrylate Acrylonitrile-Styrene-Acrylate—Chapter 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Degree of Discoloration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

47 47 47 48

Acrylic Acrylic and Acrylic Copolymer—Chapter 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Acrylic and Polyvinyl Chloride Coextrusion—Chapter 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Cellulosic Plastic Cellulose Acetate Butyrate—Chapter 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Color Retention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Table of Contents

vii

Fluoropolymers Fluoropolymers: Overview—Chapter 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Fluoropolymer Weathering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Polytetrafluoroethylene (PTFE or TFE)—Chapter 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Fluorinated Ethylene Propylene (FEP)—Chapter 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Perfluoroalkoxy (PFA and MFA)—Chapter 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Polyvinylidene Fluoride (PVDF)—Chapter 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Polychlorotrifluoroethylene (PCTFE)—Chapter 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 Ethylene-chlorotrifluoroethylene (ECTFE)—Chapter 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Ethylene-tetrafluoroethylene (ETFE)—Chapter 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Polyvinyl Fluoride (PVF)—Chapter 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Ionomer Ionomer—Chapter 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Polyphenylene Oxide Polyphenylene Oxide—Chapter 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 Weathering Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Nylon Nylon: Overview—Chapter 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Weathering Properties: General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Weathering Properties: UV Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Weathering Properties: Colored Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

viii


Nylon 6—Chapter 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

Nylon 12—Chapter 21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Nylon with Glass Fiber—Chapter 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Nylon 66—Chapter 23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Weathering Properties: Colored Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Nylon 6,6T—Chapter 24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Nylon MXD6—Chapter 25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Polyarylamide—Chapter 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Polycarbonate Polycarbonate—Chapter 27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Light Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: UV Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

147 148 148 148

Polycarbonate Blends—Chapter 28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Weathering Properties: Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Polyester Polybutylene Terephthalate—Chapter 29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Weathering Properties: Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162

Polyethylene Terephthalate—Chapter 30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

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Liquid Crystal Polymers—Chapter 31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

Polyarylate—Chapter 32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

Polyimide Polyimide—Chapter 33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Weathering Properties: General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Weathering Properties: Outer Space and Nuclear Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

Polyamideimide—Chapter 34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

Polyetherimide—Chapter 35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

Polyketone Polyetheretherketone (PEEK)—Chapter 36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

Polyolefin Polyethylene: Overview—Chapter 37 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 Weathering Properties: General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Polyethylene Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Color Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: UV Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

187 187 188 188 189

Low Density Polyethylene—Chapter 38 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 High Density Polyethylene—Chapter 39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Weathering Properties: Colored Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carbon Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . White Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellow Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Red Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Orange Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Blue and Green Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

195 195 195 195 196 196 197

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Pigment Dispersion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Part Thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

Ultrahigh Molecular Weight Polyethylene—Chapter 40 . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 Polyethylene Copolymers—Chapter 41 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214

Polypropylene—Chapter 42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Weathering Properties: Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

Polymethylpentene—Chapter 43 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

Polyphenylene Sulfide Polyphenylene Sulfide—Chapter 44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225

Polystyrene General Purpose Polystyrene—Chapter 45 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

High Impact Polystyrene—Chapter 46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

Polysulfone Polysulfone—Chapter 47 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239

Polyethersulfone—Chapter 48 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241

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Styrene Acrylonitrile Copolymer Styrene-Acrylonitrile Copolymer—Chapter 49 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244

Styrene Butadiene Copolymer Styrene-Butadiene Copolymer—Chapter 50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247 Indoor UV Light Resistance and Indirect Sunlight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247

Vinyl Resin Polyvinyl Chloride—Chapter 51 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Plasticizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Additional Plasticizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pigments and Colorants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

249 249 249 250 251 251 252 252

Chlorinated Polyvinyl Chloride—Chapter 52 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255

Thermoplastic Blends/Alloys ABS Vinyl Resin Alloy ABS Polyvinyl Chloride Alloy—Chapter 53 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

Acrylic (PMMA) Polyvinyl Alloy—Chapter 54 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

Polycarbonate ABS Alloy—Chapter 55 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261

Biodegradable Thermoplastic Alloys Biodegradable Polyethylene Films Biodegradable Polyethylene Films—Chapter 56 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263

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Degradation Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264

Starch Synthetic Resin Alloy—Chapter 57 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 Biodegradability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269

Thermosets Polyester Thermoset Polyester—Chapter 58 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 Polyester Powder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Urethane Polyesters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: UV Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

271 271 271 272

Polyurethane Polyurethane Reaction Injection Molding System—Chapter 59 . . . . . . . . . . . . . . . . . . . 273 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274

Thermoplastic Elastomers Thermoplastic Elastomers Thermoplastic Elastomers: Overview—Chapter 60 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279 Chlorinate Polyethylene Elastomer—Chapter 61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281

Olefinic Thermoplastic Elastomer—Chapter 62 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 Outdoor Accelerated Exposure Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

Polyester Thermoplastic Elastomer—Chapter 63 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301 Weathering Properties: Color Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302

Polystyrene-Butadiene-Styrene Thermoplastic—Chapter 64 . . . . . . . . . . . . . . . . . . . . . . 311 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311

Styrenic Thermoplastic Elastomer—Chapter 65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313

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Table of Contents

Weathering Properties: Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314

Urethane Thermoplastic Elastomer—Chapter 66 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315 Weathering Properties: UV Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317

Nitrile Thermoplastic Elastomers—Chapter 67 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324

Thermosetting Elastomers (Rubbers) Thermoset Elastomers or Rubbers Thermoset Elastomers or Rubbers: Overview—Chapter 68 . . . . . . . . . . . . . . . . . . . . . . . 325 Butyl Rubber, Bromobutyl Rubber, and Chlorobutyl Rubber—Chapter 69 . . . . . . . . 327 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327 Weathering Properties: Ozone Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327

Chlorosulfonated Polyethylene Rubber—Chapter 70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Color Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Curing Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Fillers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties: Plasticizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

329 329 330 331 332 332

Ethylene-Propylene Copolymer—Chapter 71 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343

Ethylene-Propylene Diene Methylene Terpolymer—Chapter 72 . . . . . . . . . . . . . . . . . . . 345 UV Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Outdoor Weather Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerated Outdoor Weathering Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerated Artificial Weathering Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Effect of Carbon Black on Weatherability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Effect of Color Pigments on Weatherability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Effective UV Screening Agents in Mineral-Filled Vulcanizates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Effect of Curing Systems on Weatherability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Effect of Plasticizers on Weatherability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ozone Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

345 345 346 347 347 347 348 348 348 348

Neoprene Rubber—Chapter 73 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374

xiv


Polybutadiene—Chapter 74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384

Polyisoprene Rubber—Chapter 75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386

Polyurethane—Chapter 76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391 Weathering Properties: Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392

Silicone Rubber—Chapter 77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393 Weathering Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393 Weathering Properties by Material Supplier Trade Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393

Fluoropolymers in Coating Applications—Appendix 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395 Architectural Fabrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fabric Base Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fabric Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fabric Top Finishes or Topcoats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weathering Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

395 395 395 395 396

Coil Coatings—Appendix 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399 Comparative Properties and Performance Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399 Coil Coating Topcoats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399

Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Trade Name Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Plastics Design Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

401 445 453 455

Preface Welcome to the Second Edition of The Effects of UV Light and Weather on Plastics and Elastomers, an extensive compilation on how the elements of weathering affect the properties and characteristics of plastics and elastomers. Designed as a reference handbook, this edition presents data in a format that allows the user to easily compare and contrast performance characteristics between different polymer families and, where possible, between the products available within a material family itself. Information was compiled from many different sources: material manufacturers, technical journals, and papers, etc. Extensive and detailed references are provided to further research materials and material applications. Amajor contributing factor to the outdoor weathering (degradation) of polymers is UV light. Temperature, moisture, and pollutants combine with the UV light and degrade polymers by different mechanisms. Design and application engineers and scientists need to know how a material will perform under various conditions. The level of deterioration expected and accepted varies by application and end use. In many instances, the application for which the material is intended has a group or society that has provided standardized tests for evaluating the materials (e.g., the Society of Automotive Engineers provides the SAE Test Methods. ASTM International publishes extensive weathering test methods often referenced by users and manufacturers of outdoor-oriented materials. The introductory chapter is designed to provide basic information on the components of weathering, material properties affected by weathering, and a review of the most common testing environments. Brief discussions of weathering stabilizers as well as color stability are included. The body of this edition presents discussion and results of weathering and outdoor exposure testing. Each of the seventy-seven chapters represents a specific material family, and the information relating to

that material is provided in textual, graphical, and tabular form. Textual information provides discussion of the material’s susceptibility or immunity to weathering or its components as well as discussion of test results. Graphical and tabular representation of data allows the user to quantitatively understand the material’s performance under specific criteria or multiple test methods. Information is included for as many materials, tests, and conditions as possible. Even where detailed metadata are not available, general information is provided. It should be noted that the content of the material chapters is representative rather than all-inclusive. That is, a polymer’s performance is presented in as much detail as possible from the sources available. All manufacturers of all outdoor materials are not included due to obvious space limitations. At the end of this book extensive references are provided in the event that further research and study are warranted. It is my hope that this reference handbook is the first book to which a designer, engineer, or scientist refers when looking for general weathering properties and comparing properties between families of polymers. However, this reference handbook should not serve as a substitute for actual testing to determine the suitability of a material for use. Please contact the manufacturers of these materials for the latest and most complete material and performance information. A special word of thanks to those who have allowed their information and test data to be included in this book. Every effort was made to present the information in its original context. As always, your feedback as a reader and user of this information is appreciated and encouraged.

Liesl K. Massey

2006

List of Graphs and Tables List of Graphs 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 1-10 1-11 1-12 1-13 1-14 1-15 1-16 1-17 1-18 1-19 1-20 1-21 1-22 1-23 1-24 1-25 1-26 1-27

Changes in Material Characteristics due to Photo-Oxidation of ABS . . . . . . . . . . . . . . . . . Outdoor Weathering Exposure Time vs. Yellowness Index of ABS . . . . . . . . . . . . . . . . . . . . Arizona Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS . . . Arizona Outdoor Weathering Exposure Time vs. Elongation of ABS . . . . . . . . . . . . . . . . . . Arizona Outdoor Weathering Exposure Time vs. Tensile Strength at Yield of ABS . . . . . . Arizona Outdoor Weathering Exposure Time vs. E Color Change of ABS . . . . . . . . . . . Arizona, Florida, and Ohio Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Florida Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS . . . . Florida Outdoor Weathering Exposure Time vs. Drop Weight Impact of ABS . . . . . . . . . . Florida Outdoor Weathering Exposure Time vs. E Color Change of ABS . . . . . . . . . . . . Florida Weathering Exposure Time vs. Chip Impact Strength of ABS (White Rovel Capstock and Acrylic Capstock) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Florida Weathering Exposure Time vs. Chip Impact Strength of ABS (Natural Resin) . . . Ohio Outdoor Weathering Exposure Time vs. E Color Change of ABS . . . . . . . . . . . . . . Ohio Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS . . . . . . Okinawa, Japan, Outdoor Weathering Exposure Time vs. E Color Change of ABS . . . Okinawa, Japan, Outdoor Weathering Exposure Time vs. Dynstat Impact Strength Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Okinawa, Japan, Outdoor Weathering Exposure Time vs. Elongation at Break Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Okinawa, Japan, Outdoor Weathering Exposure Time vs. Gloss Retained of ABS . . . . . West Virginia Outdoor Weathering Exposure Time vs. Falling Dart Impact of ABS at −40◦ C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Falling Dart Impact of ABS at 23◦ C, −25◦ C, and −40◦ C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Falling Dart Impact of ABS at 23◦ C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Flexural Modulus Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Flexural Strength of ABS at −40◦ C and 23◦ C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Flexural Strength Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Izod Impact Strength Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Virginia Outdoor Weathering Exposure Time vs. Tensile Strength Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sunshine Weatherometer Exposure Time vs. Dynstat Impact Strength Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16 16 17 17 18 18 19 19 20 20 21 21 22 22 23 23 24 24 25 25 26 26 27 27 28 28 29

xviii 1-28 1-29 1-30 1-31 1-32 1-33 2-1 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8 3-9 3-10 3-11 4-1 4-2 4-3 4-4 4-5 4-6 4-7 4-8 4-9 4-10

The Effects of UV Light and Weather on Plastics and Elastomers Sunshine Weatherometer Exposure Time vs. Elongation at Break Retained of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sunshine Weatherometer Exposure Time vs. Gloss Retained of ABS . . . . . . . . . . . . . . . . Weatherometer Exposure Time vs. Impact Strength of ABS . . . . . . . . . . . . . . . . . . . . . . . . . Xenotest 1200 Exposure Time vs. Impact Strength of ABS . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerated Indoor UV Exposure Time vs. E Color Change of ABS . . . . . . . . . . . . . . . . Yellowness Index of UVA- and HALS-Stabilized ABS after Outdoor Weathering in Switzerland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after Arizona, Florida, and New York Outdoor Weathering of GE Plastics Cycolac® /Geloy® Resin Systems Compared to PVC . . . . . . . . . . . . . . . . . . . . . . . . Relative Tensile Strength after Accelerated Interior Weathering According to SAE J1885 for Dupont Delrin® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Relative Gloss after Accelerated Interior Weathering According to SAE J1885 for DuPont Delrin® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Changes in Mechanical Properties after Light Exposure of Ticona Celcon® UV90Z . . . . Outdoor Exposure Time vs. Impact Strength Retained of BASF Ultraform® N 2320 and Ultraform® N 2325 U Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New Jersey and Arizona Outdoor Exposure Time vs.Tensile Impact Strength of Ticona Celcon® M90 and UV90 Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New Jersey and Arizona Outdoor Exposure Time vs.Tensile Strength atYield of Ticona Celcon® M90 Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New Jersey Outdoor Exposure Time vs. Tensile Strength at Yield of Ticona Celcon® GC25 A Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . QUV Exposure Time vs. E Color Change of Ticona Celcon® Acetal Copolymer . . . . . . Sunshine Weatherometer Exposure Time vs. Elongation Retained of Mitsubishi Iupital® F20 Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sunshine Weatherometer Exposure Time vs. Tensile Strength Retained of Mitsubishi Iupital® F20 Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Xenon Arc Weatherometer Exposure Time vs. Relative Gloss of BASF Ultraform® N Acetal Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowness Index after Outdoor Exposure for BASF Luran® S 797 and Luran® S 776 ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Impact Strength Retained after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elongation at Break Retained after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gloss Retained after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Impact Strength Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® T110 and T120 ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Impact Strength Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elongation at Break Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gloss Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® T115 and T110 ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gloss Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

29 30 30 31 31 32 33 40 40 41 41 42 42 43 43 44 44 45 49 50 50 51 51 52 52 53 53 54

List of Graphs and Tables 4-11 4-12 4-13 4-14 5-1 5-2 5-3 5-4 5-5 5-6 5-7 7-1 7-2 7-3 8-1 10-1 11-1 11-2 11-3 12-1 12-2 12-3 12-4 12-5 13-1 13-2 13-3

Impact Strength after Weatherometer Exposure for BASF Luran® S ASA Polymer at Different Test Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Impact Strength after Xenotest 1200 Exposure for BASF Luran® S 797 and Luran® S 776 ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowness Index of ABS, Luran® S, and Blends after Exposure to Sunshine . . . . . . . . . . Penetration Energy after Exposure to Sunshine on 2-mm Thick Disks of Luran® S 778 T, Luran® S 778 T UV, Luran® S KR 2861/1 C, ABS-UV, and PC+ABS . . . . . . . . . . . Light Transmission for Acrylic, Cyrolon® UVP Polycarbonate Sheet, and Polycarbonate after Weathering Exposure as per ASTM D1003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowness Index for Acrylic, Cyrolon® UVP Polycarbonate Sheet, and Polycarbonate after Weathering Exposure as per ASTM D1925 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percentage Haze for Acrylic, Cyrolon® UVP Polycarbonate Sheet, and Polycarbonate after Weathering Exposure as per ASTM D1003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Luminous Transmittance, Haze, Yellowness Index, and Surface Gloss of Plexiglas® V825 after Florida and Arizona Weathering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Luminous Transmittance, Haze, Yellowness Index, and Surface Gloss of Plexiglas® DR101 after Florida and Arizona Weathering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Luminous Transmittance, Haze, Yellowness Index, and Surface Gloss of Plexiglas® V920 after Florida and Arizona Weathering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after Atlas Weatherometer Exposure of Novacor NAS® 30, NAS® 36, Zylar® 533, and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength at Break after Arizona Weathering for Eastman Tenite® Butyrate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elongation at Break after Arizona Weathering for Eastman Tenite® Butyrate . . . . . . . . . . Impact Strength after Weathering for Eastman Tenite® Butyrate . . . . . . . . . . . . . . . . . . . . . Mechanical Properties of PVDF, ETFE, and PVF Films after South Florida Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Retention of Tensile Strength and Percentage Elongation after Outdoor Exposure for DuPont FEP Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after Carbon Arc Weatherometer Accelerated Weathering (Dew Cycle) for PFA and MFA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength Retention after Carbon Arc Weatherometer Accelerated Weathering (Dew Cycle) for PFA and MFA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elongation Retention after Carbon Arc Weatherometer Accelerated Weathering (Dew Cycle) for PFA and MFA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Retention of Tensile Strength and Elongation after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for PVDF Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for Solvay Solexis Hylar® 5000 PVDF Pigmented Coatings . . . . . . . . . . . . . . . . . . . Gloss Retention after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for Solvay Solexis Hylar® 5000 PVDF Pigmented Coatings . . . . . . . . . . . . . . . . . . . . . . . . . Chalk Rating after Florida Exposure (45◦ Angle South) for Commercial White Paints . . . Gloss Retention after Florida Exposure (45◦ Angle South) for Commercial White Paints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elongation Retained in the Machine Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elongation Retained in the Transverse Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength Retained in the Machine Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

xix

54 55 55 56 59 59 60 61 62 63 63 68 68 69 71 77 79 80 80 84 84 85 85 86 87 88 88

xx


13-4

Tensile Strength Retained in the Transverse Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-1 Retention of Tensile Strength and Elongation after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for Solvay Solexis Halar® ECTFE Film . . . . . . . . . . . . . . . . . . 14-2 Retention of Tensile Strength and Elongation after QUV Accelerated Weathering Exposure, UVB-313, for Solvay Solexis Halar® ECTFE Film . . . . . . . . . . . . . . . . . . . . . . . . 14-3 Color Change, E, after QUV Accelerated Weathering Exposure, UVB-313, for Solvay Solexis Halar® ECTFE Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-1 Percentage of Initial Properties Retained after South Florida Weathering Exposure at an Angle of 45◦ Facing South for DuPont Tedlar® PVF Film . . . . . . . . . . . . . . . . . . . . . . . . . 16-2 Percentage Gloss Retention after South Florida Weathering Exposure at an Angle of 45◦ Facing South for DuPont Tedlar® PVF Film and Pigmented Vinyl Film . . . . . . . . . . . . 16-3 Average Rate of UV Absorber Degradation in Free-Standing DuPont Tedlar® PVF Film after Florida Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-4 Color Stability of DuPont Tedlar® PVF Film after Exposure to Atlas Sunshine Arc Weatherometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-5 Percentage of Initial Properties Retained after Atlas Sunshine Arc Weatherometer Exposure of DuPont Tedlar® PVF Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-6 Typical Color Change Range of a Variety of Pigmented DuPont Tedlar® SP Films after Xenon Arc Exposure as per the SAE J1960 Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-7 Gloss Retention of Refinish Paint, Gel Coat, and DuPont Tedlar® SP Film after Xenon Arc Exposure as per the SAE J1960 Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-8 Gloss Retention of Acrylic Film, ASA/AES Copolymer, and DuPont Tedlar® SP Film after Xenon Arc Exposure as per the SAE J1960 Method . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-1 Change in Color, E, after Accelerated Indoor UV Exposure of Modified PPO . . . . . . . . 18-2 Dart Drop Impact Strength after Arizona Outdoor Weathering Exposure of Modified PPO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-3 Percentage Elongation after Arizona Outdoor Weathering Exposure of Modified PPO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-4 Tensile Strength after Arizona Outdoor Weathering Exposure of Modified PPO . . . . . . . . 18-5 Change in Color, E, after Arizona Outdoor Weathering Exposure of Modified PPO . . . 18-6 Change in Color, E, after Ohio Outdoor Weathering Exposure of Modified PPO . . . . . 18-7 Dart Drop Impact Strength after Ohio Outdoor Weathering Exposure of Modified PPO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-1 Elongation at Break after Outdoor Exposure for Ube Ube® Nylon 6 . . . . . . . . . . . . . . . . . . 20-2 Flexural Modulus after Outdoor Exposure for Ube Ube® Nylon 6 . . . . . . . . . . . . . . . . . . . . 20-3 Notched Izod Impact Strength after Outdoor Exposure for Ube Ube® Nylon 6 . . . . . . . . . 20-4 Tensile Strength after Outdoor Exposure for Ube Ube® Nylon 6 . . . . . . . . . . . . . . . . . . . . . 20-5 Flexural Strength at Break after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6 . . . 20-6 Flexural Modulus after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6 . . . . . . . . . . . . 20-7 Notched Izod Impact Strength after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-8 Weight Change after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6 . . . . . . . . . . . . . 20-9 Flexural Strength after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6 . . . . . . . . . . . . 20-10 Tensile Strength after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6 . . . . . . . . . . . . . 20-11 Elongation after Sunshine Weatherometer Exposure of Nylon 6 . . . . . . . . . . . . . . . . . . . . . 20-12 Tensile Strength after Sunshine Weatherometer Exposure of Nylon 6 . . . . . . . . . . . . . . . . 21-1 Change in Color, E, after Weatherometer Exposure of EMS Grilamid® TR 55, TR 55 LX, TR 90, and TR 90 UV Nylon 12 Compared to Other Polymers . . . . . . . . . . . . . . . . . . .

89 92 92 93 98 98 99 99 100 100 101 101 110 111 111 112 112 113 113 119 120 120 121 121 122 122 123 123 124 124 125 128

List of Graphs and Tables Yellow Index (YI) after Weathering Exposure as per ASTM D1975 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-3 Tensile Impact Strength after Weatherometer Exposure for EMS Grilamid® TR 55, TR 55 LX, and TR 55 LY Nylon 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-4 Tensile Impact Strength after Weatherometer Exposure for EMS Grilamid® TR 90 and TR 90 UV Compared to Other Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-5 Tensile Impact Strength Half-Life after Weathering for EMS Grilamid® TR 90, TR 90 LX, and TR 90 UV Compared to Other Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-6 Yield Strength after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-7 Percentage Retention of Yield Strength after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX . . . . . . . . . . . . . . . . . . . . . . . . . 21-8 Percentage Retention of Elongation at Break after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX . . . . . . . . . . . . . . . . . . 21-9 Percentage Retention of Work to Break after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, and TR 55 LX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-10 Transparency of EMS Grilamid® and EMS Grivory® Compared to Glass and Other Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-11 Transparency in the Visible Spectrum of EMS Grilamid® Compared to Other Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-1 Flexural Modulus after Outdoor Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-2 Notched Izod Impact Strength after Outdoor Weathering Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-3 Flexural Strength after Outdoor Weathering Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-4 Tensile Strength after Outdoor Weathering Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-5 Elongation (%) after Sunshine Weatherometer Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-6 Tensile Strength after Sunshine Weatherometer Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-1 Flexural Strength after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-2 Flexural Modulus after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-3 Notched Izod Impact Strength after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-4 Weight Change after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-1 Light Transmission of UV-Stabilized GE Plastics Lexan® . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-2 Light Transmission of Transparent GE Plastics Lexan® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-3 Transmittance through Transparent GE Plastics Lexan® after Florida Outdoor Exposure as per ASTM G7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-4 Yellowness Index after Florida Outdoor Exposure as per ASTM G7 for GE Plastics Lexan® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-5 Haze after Accelerated Outdoor Exposure of Coated and Uncoated Transparent GE Plastics Lexan® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-6 Yellowness Index after Accelerated Outdoor Exposure of Coated and Uncoated Transparent GE Plastics Lexan® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

xxi

21-2

128 129 129 130 130 130 131 131 132 132 139 140 140 141 141 142 144 144 145 145 152 152 153 153 153 154

xxii 27-7 27-8 27-9 27-10 27-11 27-12 27-13 27-14 28-1

28-2

28-3 29-1 29-2 29-3 29-4 29-5 29-6 29-7 29-8 30-1 30-2 33-1 33-2 33-3 33-4 33-5 33-6 34-1 34-2 35-1

The Effects of UV Light and Weather on Plastics and Elastomers Yellowness Index after Xenon Arc Weathering for GE Plastics Lexan® . . . . . . . . . . . . . . . . Change in Yellowness Index, YI, after Whirlygig Accelerated Outdoor Exposure of GE Plastics Lexan® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowness Index after Kentucky Outdoor Weathering for GE Lexan® S-100 Sheet . . . . . Yellowness Index after EMMAQUA Accelerated Arizona Weathering for GE Lexan® S-100 Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Haze (%) after Carbon Arc XW Weathering for GE Lexan® 153 . . . . . . . . . . . . . . . . . . . . . Yellowness Index after Twin Carbon Arc Weathering for GE Lexan® S-100 Sheet . . . . . . Yellowness Index after Outdoor Weathering for PC Natural and UV Stabilized with Tinuvin® 234 Benzotriazole UV Absorber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gloss (20◦ ) Retention after Xenon Arc Weathering of Twin Wall PC Sheets (10 mm) Stabilized with Tinuvin® UV Absorbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, of Pigmented GE Plastics Cycoloy® C1100 PC/ABS after Accelerated UV Exposure as per SAE J1885 (ATLAS Ci65XW) and DIN75202 (XENON450) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, of Pigmented GE Plastics Cycoloy® C1100 PC/ABS after Accelerated UV Exposure as per SAE J1885 (ATLAS Ci65XW) and DIN75202 (XENON450) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Development after Xenon Arc Weatherometer Exposure of PC/ABS (50/50) Blend with Tinuvin® 234 UV Stabilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Notched Izod Impact Strength after Florida and Arizona Outdoor Weathering for Ticona Celanex® PBT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Florida and Arizona Outdoor Weathering for Ticona Celanex® PBT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flexural Strength at Break after Hiratsuka, Japan, Outdoor Exposure of PBT Polyester . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flexural Modulus after Hiratsuka, Japan, Outdoor Exposure of PBT Polyester . . . . . . . . Notched Izod Impact Strength after Hiratsuka, Japan, Outdoor Exposure of PBT Polyester . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Weight Change after Hiratsuka, Japan, Outdoor Exposure of PBT Polyester . . . . . . . . . . Tensile Strength Retained after Weatherometer Exposure of Ticona Celanex® PBT . . . . Change in Yellowness Index, YI, after Light Exposure of PBT Injection-Molded Plaques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Sunshine Weatherometer Exposure of PET . . . . . . . . . . . . . . . . . . . Elongation after Sunshine Weatherometer Exposure of PET . . . . . . . . . . . . . . . . . . . . . . . . Ultimate Elongation after Florida Aging of DuPont Kapton® Film . . . . . . . . . . . . . . . . . . . . . Ultimate Elongation after Atlas Weatherometer Exposure of DuPont Kapton® . . . . . . . . . Elongation Retained after Sunshine Weatherometer Exposure for UBE Upilex® R and UBE Upilex® S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flexural Strength Retained after Sunshine Weatherometer Exposure for UBE Upimol® R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength Retained after Sunshine Weatherometer Exposure for UBE Upilex® R and UBE Upilex® S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flexural Strength Retained after UV-CON Exposure for UBE Upimol® R . . . . . . . . . . . . . . Elongation after Atlas Sunshine Carbon Arc Weatherometer Exposure for Torlon® 4203L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Atlas Sunshine Carbon Arc Weatherometer Exposure for Torlon® 4203L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Xenon Arc Weatherometer Exposure of GE Plastics Ultem® 1000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

154 154 155 155 156 156 157 157

159

160 160 162 162 163 163 164 164 165 165 171 172 177 178 178 179 179 180 181 182 183

List of Graphs and Tables Retention of Elongation after Atlas Weatherometer Exposure of High Density Polyethylene (HDPE) Plaques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37-2 Impact Strength Retained after Atlas Weatherometer Exposure of Linear Low Density Polyethylene (LLDPE) Plaques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37-3 Kilolangleys of Exposure to Create 50% Tensile Strength Retained after Arizona Outdoor Exposure of HDPE-Pigmented Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37-4 Tensile Strength after Arizona Exposure of 0.96 Density Unstabilized Polyethylene with Various Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-1 Tensile Strength after Arizona Outdoor Weathering of Yellow Chevron Phillips Marlex® HDPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-2 Tensile Strength after Weatherometer Exposure of Yellow Chevron Phillips Marlex® HDPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-3 Tensile Strength after Weatherometer Exposure of Red Chevron Phillips Marlex® HDPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-4 Tensile Strength after Weatherometer Exposure of Unstabilized Red Chevron Phillips Marlex® HDPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-5 Tensile Strength after Weatherometer Exposure of Orange Chevron Phillips Marlex® HDPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-6 Tensile Strength after Weatherometer Exposure of Blue Chevron Phillips Marlex® HDPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-7 Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with 2% Zinc Oxide and 2% TiO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-8 Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with Varying Concentrations of TiO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-9 Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with 1% TiO2 and UV Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-10 Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with Various Degrees of Pigment Dispersion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-1 Kilolangleys to 50% Retained Tensile Strength and Days to Embrittlement after 45◦ South Florida and Oven Aging at 120◦ C of UV-Stabilized Polypropylene Plaques . . . . . . 42-2 Surface Roughness after 45◦ South Florida Weathering Exposure of UV-Stabilized Polypropylene Plaques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-3 Color Change, E, after Accelerated Weathering for UV-Stabilized Polypropylene Automotive Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43-1 Izod Impact Strength Retained after Weatherometer Exposure for Mitsui TPX™ RT18 Polymethylpentene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45-1 Yellowness Index after Atlas Fadeometer Exposure of General Purpose Polystyrene . . . 45-2 Yellowness Index after Fluorescent Lamp Exposure of BASF Polystyrol® General Purpose Polystyrene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46-1 Yellowness Index after Fadeometer Exposure of Dow Styron® Impact and Flame-Retardand Polystyrene and Dow Styron® Unmodified Polystyrene . . . . . . . . . . . . . 46-2 Color Change, E, after Florida Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46-3 Color Change, E, after Arizona Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46-4 Color Change, E, after Kentucky Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46-5 Color Change, E, after Illinois Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

xxiii

37-1

191 191 192 192 205 205 206 206 207 207 208 208 209 209 220 221 221 223 229 229 233 234 234 235 235

xxiv


46-6

Impact Property Retention, Energy at Maximum Load, after 3000 hours of Atlas Weather-Ometers® Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46-7 Impact Property Retention, Total Energy, after 3000 hours of Atlas Weather-Ometers® Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . 46-8 Impact Property Retention, Maximum Load, after 3000 hours of Atlas WeatherOmeters® Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . 46-9 Impact Strength after Xenon Arc Weathering of HIPS as per ISO 4892-2 . . . . . . . . . . . . . 46-10 Yellowness Index after Xenon Arc Weathering of HIPS as per ISO 4892-2 . . . . . . . . . . . . 47-1 Tensile Strength after Xenon Arc Weatherometer Exposure of Polysulfone . . . . . . . . . . . . 48-1 Tensile Strength after Xenon Arc Weatherometer Exposure of PES . . . . . . . . . . . . . . . . . . 49-1 Yellowness Index after Arizona Outdoor Weathering of Dow Tyril® SAN Copolymer . . . . 49-2 Yellowness Index after UV-CON Accelerated Weathering Exposure of SAN Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51-1 Elongation after Xenon Exposure of Various UV Stabilized PVC Formulations . . . . . . . . 51-2 Elongation Retention after Xenon Exposure of Various UV-Stabilized PVC Formulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51-3 Yellowness Index after Xenon Exposure of Various UV-Stabilized PVC Formulations . . . 52-1 Drop Weight Impact Strength Retained after Florida Outdoor Weathering Exposure of CPVC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56-1 Weight Loss of Mater-Bi Biodegradable Film after Burying in Various Soils . . . . . . . . . . . 56-2 Elongation Retained after Xenon Weatherometer Exposure of Starch-Modified Low Density Polyethylene (LDPE) Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56-3 Elongation Retained after Composing of Starch-Modified LDPE Film . . . . . . . . . . . . . . . . 56-4 Starch Content Retained after Burial of Ecostar Starch-Modified PE Film . . . . . . . . . . . . . 58-1 Yellowness Index after Xenon Arc Weathering of Unsaturated Polyester . . . . . . . . . . . . . . 59-1 Change in color, b, after Florida Outdoor Weathering Exposure of Recticel Colo-Fast® Polyurethane RIM System and Aromatic Polyurethane . . . . . . . . . . . . . . . . . . . 59-2 Gloss Retained after QUV Weathering Exposure of Recticel Colo-Fast® Polyurethane RIM System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59-3 Gloss Retained after Sunshine Carbon Arc Weathering Exposure of Recticel Colo-Fast® Polyurethane RIM System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59-4 Results of Visual Inspection after EMMAQUA Accelerated Exposure of Recticel Colo-Fast® Polyurethane RIM System and Several Other Materials . . . . . . . . . . . . . . . . . . 62-1 Carbonyl Formation after Xenon Arc Weatherometer Exposure of Dow Chemical Company’s Engage™ Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62-2 Decrease in Molecular Weight after Xenon Arc Weatherometer Exposure of Dow Chemical Company’s Engage™ Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . 66-1 Elongation after QUV Exposure of Dow Pellethane® 2103-80 AEF Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66-2 Tensile Strength after QUV Exposure of Dow Pellethane® 2103-80 AEF Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66-3 Yellowness Index after QUV Exposure of Dow Pellethane® 2103-80 AEF Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66-4 Yellowness Index after QUV Exposure of BASF Elastollan® 1185A-10 Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66-5 Tensile Strength after Xenon Weatherometer Exposure of BASF Elastollan® 1185A-10 Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-1 Elongation at Break after Delaware Outdoor Exposure for DuPont Elastomers Hypalon® 20 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

236 236 237 237 238 240 241 244 245 253 253 254 255 265 266 266 267 272 276 277 277 278 298 299 320 320 321 321 322 341

List of Graphs and Tables

xxv

71-1 71-2

343

72-1 72-2 76-1 A1-1 A1-2 A1-3

Carbonyl Formation after Xenon Arc Exposure for Ethylene-Propylene Copolymer . . . . Decrease in Molecular Weight after Xenon Arc Exposure for Ethylene-Propylene Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carbonyl Formation after Xenon Arc Weatherometer Exposure of EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Decrease in Molecular Weight after Xenon Arc Weatherometer Exposure of EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Change in Color, b, after Florida Outdoor Weathering of Polyurethane . . . . . . . . . . . . . . Top Finish Thickness after Accelerated Florida Outdoor Exposure Testing for Acrylic, PVDF, and DuPont Tedlar® PVF Top Finishes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after Accelerated Florida Outdoor Exposure Testing for Acrylic, PVDF, and DuPont Tedlar® PVF Top Finishes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gloss Change, 60◦ Gloss, after Accelerated Florida Outdoor Exposure Testing for Acrylic, PVDF, and DuPont Tedlar® PVF Top Finishes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

344 372 372 392 397 397 398

List of Tables 1-1 1-2 1-3 1-4 3-1 3-2 3-3 3-4 3-5 3-6 3-7 4-1 4-2 4-3 5-1 5-2 5-3 9-1 10-1 10-2

Outdoor Weathering of White ABS in Florida . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Outdoor Weathering of ABS in Ludwigshafen, Germany . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerated Indoor Exposure of GE Plastics Cycolac® VW300 ABS by HPUV . . . . . . . . Accelerated Indoor Exposure of GE Plastics Cycolac® KJB ABS to Fluorescent Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Differences, E, after Light Exposure for Pigmented Ticona Celcon® UV90Z (GM and Ford Automotive Colors) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Differences, E, after Light Exposure for Pigmented Ticona Celcon® UV90Z . . . . Color Differences, E, after Light Exposure for Unpigmented Ticona Celcon® M90UV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Differences, E, after Florida Weathering for Ticona Hostaform® Materials . . . . . . Color Differences, E, after Xenotest 1200 for Ticona Hostaform® C 9021 LS Blue 80/4065 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Elongation after Arizona Weathering Exposure for DuPont Delrin® 507 BK601 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Elongation after Michigan Weathering Exposure for DuPont Delrin® 507 BK601 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Properties after Florida (45◦ South Facing) Outdoor Exposure for Pigmented GE Plastics Geloy® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Long-Term Material Performance for GE Plastics Geloy® . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowness Index after Outdoor Weathering in Ludwigshafen, Germany, for BASF Luran® S 776 S ASA Polymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cyro Acrylite® GP F Acrylic Sheet after Xenon Arc Accelerated Weathering . . . . . . . . . . Cyro Acrylite® GP FL Acrylic Sheet after Xenon Arc Accelerated Weathering . . . . . . . . . Cyro Acrylite® GP FLW Acrylic Sheet after Xenon Arc Accelerated Weathering . . . . . . . Mechanical Properties of PTFE Film after South Florida Exposure . . . . . . . . . . . . . . . . . . Mechanical Properties after 20-Year South Florida Exposure for Two Thicknesses of FEP Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Break Elongation after 20-Year South Florida Exposure for Two Thicknesses of FEP Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14 14 15 15 37 37 38 38 38 39 39 48 48 49 58 58 58 73 75 76

xxvi 10-3 10-4 10-5 12-1 12-2 12-3 12-4 14-1 15-1 17-1 17-2 17-3

17-4

17-5 18-1

20-1 20-2 22-1 27-1 27-2 27-3

27-4 27-5 30-1

The Effects of UV Light and Weather on Plastics and Elastomers Material Properties (Dielectric Strength, Tensile Strength, Elongation at Break, and MIT Flex Life) of FEP Film after South Florida Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties (Tensile Strength and Elongation at Break) of FEP Film after South Florida Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Properties of FEP Film after South Florida Exposure . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties and Yellowness Index after Arizona Outdoor Weathering Exposure for Solvey Solexis Solef ® 11010 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellowness Index after QUV Accelerated Weathering Exposure (UV-B 313) for Solvey Solexis Solef ® 21508 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Retention of Mechanical Properties after Outdoor Weathering of Arkema Kynar® PVDF Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Retention of Mechanical Properties after Xenon Arc Weatherometer Exposure of PVDF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerated Weathering of Solvay Solexis Halar® ECTFE in a Xenon Arc Weatherometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerated Weathering of DuPont Tefzel® 200 ETFE in a Weatherometer . . . . . . . . . . . . Physical Properties and Visual Appearance after Florida and Arizona Outdoor Weathering for UV-Stabilized DuPont Surlyn® Ionomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Physical Properties and Visual Appearance after Accelerated Weathering in an Atlas Weatherometer for Zinc Ion Type UV-Stabilized DuPont Surlyn® Ionomer . . . . . . . . . . . . . Physical Properties and Visual Appearance after Accelerated Weathering in an Atlas Weatherometer for Zinc Ion Type UV- and Antioxidant-Stabilized, Pigmented DuPont Surlyn® Ionomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Physical Properties and Visual Appearance after Accelerated Weathering in an Atlas Weatherometer for Sodium Ion Type UV- and Antioxidant-Stabilized, Pigmented DuPont Surlyn® Ionomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Physical Properties and Visual Appearance after Accelerated Weathering in a QUV Weatherometer for Zinc Ion Type DuPont Surlyn® Ionomer . . . . . . . . . . . . . . . . . . . . . . . . . . Change in Yellowness Index and Percentage Gloss Retained after Outdoor Weathering Exposure in Arizona, Florida, and New York for GE Plastics Noryl® Modified PPO. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after Outdoor Weathering Exposure in Florida for BASF Capron® Nylon 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after Outdoor Weathering Exposure in California and Pennsylvania for LNP Engineering Plastics® Nylon 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties Retained after Outdoor Weathering in California and Pennsylvania for LNP (a Division of GE Plastics) Glass-Reinforced Nylon 610 . . . . . . . . . . . . . . . . . . . . . Izod Impact and Surface and Appearance Properties after Arizona Outdoor Exposure of Dow Calibre® 300 6 MFR without and with UV Stabilizer . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after California and Pennsylvania Outdoor Exposure of LNP Engineering Plastics PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties and Surface and Appearance Properties after Arizona Accelerated Outdoor Weathering and Kentucky Outdoor Weathering for GE Lexan® S-100 and Lexan® 100 Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after XW Accelerated Weathering for GE Lexan® 303 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Change in color, E, after Accelerated Indoor Exposure of GE Lexan® 920A by HPUV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Elongation Retained after Arizona Outdoor Weathering of DuPont Rynite® 545 NC10, Rynite® 545 BK504, and Rynite® 935 BK505 . . . . . . . . . . . .

76 76 77 82 82 83 83 91 95 104 105

106

107 108

110 118 119 133 148 149

150 151 151 168

List of Graphs and Tables 30-2 30-3 30-4 30-5

31-1 36-1 36-2 37-1 37-2 37-3 39-1 39-2 39-3 39-4 39-5 39-6 39-7 41-1 42-1 42-2 42-3 42-4 42-5 44-1 45-1

Tensile Strength and Elongation Retained after Arizona Outdoor Weathering of DuPont Rynite® 530 NC10 and Rynite® 530 BK503 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Elongation Retained after Florida Outdoor Weathering of DuPont Rynite® 530 NC10 and Rynite® 530 BK503 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Elongation Retained after Florida Outdoor Weathering of DuPont Rynite® 545 NC10 and Rynite® 545 BK504 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength and Elongation Retained after Arizona EMMA and EMMAQUA Weathering of DuPont Rynite® 530 NC10, Rynite® 530 BK503, Rynite® 545 NC10, and Rynite® 545 BK504 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after Xenon Arc Accelerated Weathering for Ticona Vectra® A950, Vectra® A130, Vectra® B950, and Vectra® A540 . . . . . . . . . . . . . . . . . . . . . . Tensile Strength Retained after United Kingdom Outdoor Weathering Exposure of Natural, Black, and White Pigmented Victrex® PEEK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength Retained after United Kingdom Outdoor Weathering Exposure of Pigmented Victrex® PEEK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Life after Outdoor Weathering for Cyanox 2777, Cyasorb UV 531, and Cyasorb UV-3346 UV-Stabilized Polyethylene Greenhouse Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Life after Outdoor Weathering for Cyasorb UV-3346 UV-Stabilized Polyethylene Greenhouse Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after California and Pennsylvania Outdoor Exposure of Glass-Reinforced LNP Polyethylene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after EMMA Accelerated Weathering of Chevron Phillips Marlex® HDPE with Channel Black and Furnace Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with Various Degrees of Pigment Dispersion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with UV Absorber and Various Orange Pigment Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with 2% Cadmium Yellow Pigment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with UV Absorber and Various Yellow Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with 2% TiO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Surface and Appearance after Accelerated Weathering of Chevron Phillips Marlex® HDPE with UV Absorber, Various Antioxidants and Green Pigment . . . . . . . . . . . . . . . . . . Elongation Retained after Xenon Arc Weatherometer Exposure of Ethylene-Vinyl Acetate Polyethylene Copolymer Greenhouse Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conversions of EMMAQUA to Real-Time Performance by Geographic Location . . . . . . . Tensile Strength after Florida and Puerto Rico Outdoor Weathering of Polypropylene Containing Various Antioxidant Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after California and Pennsylvania Outdoor Weathering of Glass-Reinforced Polypropylene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensile Strength Retained after Puerto Rico Outdoor Weathering for Polypropylene Containing Antioxidants and UV Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color and Gloss Changes after QUV Accelerated Weathering for Polypropylene Containing Microcal Calcium Carbonate and Pure Calcium Carbonate . . . . . . . . . . . . . . . Material Properties Retained and Surface Erosion after Atlas Weatherometer Accelerated Weathering of Chevron Phillips Ryton® R4 Polyphenylene Sulfide . . . . . . . . Photo-Oxidation of Polystyrene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

xxvii

169 169 170

171 174 185 186 189 190 190 198 199 200 201 202 203 204 214 216 217 218 219 220 225 227

xxviii 45-2 46-1 46-2 46-3 47-1 49-1 51-1 51-2 51-3 51-4 51-5 53-1 55-1 56-1 56-2 56-3 59-1 59-2 59-3 62-1 62-2 62-3 62-4 62-5 62-6 62-7 62-8 62-9

The Effects of UV Light and Weather on Plastics and Elastomers Mechanical Properties Retained after California and Pennsylvania Outdoor Weathering of Glass-Reinforced General Purpose Polystyrene . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after 18 Months of Florida Outdoor Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after 18 Months of Florida Outdoor Exposure and 3000 hours of Accelerated Weathering for NOVA Chemicals Styrosun® HIPS and Other Materials . . . . Impact Retention after 3000 hours of Accelerated Weathering for NOVA Chemicals Styrosun® HIPS and Other Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained after Outdoor Weathering of Glass-Reinforced Polysulfone in California and Pennsylvania . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Surface and Appearance Properties after Arizona Outdoor Weathering of Dow Tyril® SAN Copolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exposure Results of Various Plasticized Films with Varying Thicknesses . . . . . . . . . . . . . Outdoor Life of DOP-Plasticized 4 mil (100 µm) Thick Films With Varied Plasticizer Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direct Weathering of Select Plasticizers in PVC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Underglass Weathering of Select Plasticizers in PVC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Titanium Dioxide in Films of Three Thicknesses Exposed in Florida . . . . . . . . . . . . . . . . . . Color Change after Accelerated QUV Weathering of Novatec Novaloy® 9000 ABS/PVC Alloy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Color Change, E, after HPUV and Xenon Arc Accelerated Indoor Exposure of Dow Chemical Pulse 1745 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Degradation of Various Mulching Films after Exposure to Natural Solar Radiation at Different Periods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Days From Mulching to Appearance of Fracture in Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Degradation of Mulching Films Incorporated with Different Starch Content . . . . . . . . . . . . Surface and Appearance Changes after Xenon Arc Accelerated Weathering Exposure (GM Specifications) of Recticel Colo-Fast® Polyurethane RIM System . . . . . . . . . . . . . . . Surface and Appearance Changes after Xenon Arc Accelerated Weathering Exposure (Japanese Specifications) of Recticel Colo-Fast® Polyurethane RIM System . . . . . . . . . . Surface and Appearance Changes after Fadeometer Accelerated Weathering Exposure of Recticel Colo-Fast® Polyurethane RIM System . . . . . . . . . . . . . . . . . . . . . . . . Retention of Mechanical Properties after Xenon Arc Exposure for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after Arizona Outdoor Exposure for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after Arizona Outdoor Exposure with Spray for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after Florida Outdoor Exposure for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after Florida Outdoor Exposure with Spray for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after EMMA Accelerated Exposure with Spray for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after EMMAQUA Accelerated Exposure for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after Xenon Arc Exposure for Black UV Grades of Advanced Elastomer Systems Santoprene™ TPV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Properties after Xenon Arc SAE J1960 Exterior Automotive Testing for Advanced Elastomer Systems Santoprene™ TPV High-Flow Grades . . . . . . . . . . . . . . . . .

228 232 232 233 239 244 250 250 251 251 252 258 261 264 265 265 274 275 276 285 286 287 288 289 290 291 292 293

List of Graphs and Tables 62-10 Material Properties after UV-CON Accelerated Indoor Exposure of PolyOne Forprene® Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62-11 UV Resistance after Accelerated UV Light Exposure of PolyOne Forprene® Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62-12 Ozone Resistance of PolyOne Forprene® Olefinic Thermoplastic Elastomer . . . . . . . . . . 62-13 Ozone Resistance of Advanced Elastomer Systems Santoprene™ Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62-14 Ozone Resistance of Dow Chemical Company’s Engage™ Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62-15 Ozone Resistance of Advanced Elastomer Systems Santoprene™ Black Olefinic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-1 Material Properties Retained and Surface and Appearance after Florida Outdoor Weathering for DuPont Hytrel® Polyester Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . 63-2 Material Properties Retained and Surface and Appearance after Florida Outdoor Weathering for DuPont Hytrel® 40D Polyester Thermoplastic Elastomer with Carbon Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-3 Material Properties Retained after Florida Outdoor Weathering for DuPont Hytrel® 5556 Polyester Thermoplastic Elastomer with Carbon Black . . . . . . . . . . . . . . . . . . . . . . . . 63-4 Material Properties Retained and Surface and Appearance after Florida Outdoor Weathering for Varying Thicknesses of DuPont Hytrel® 6345 Polyester Thermoplastic Elastomer Films with Carbon Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-5 Material Properties Retained after Carbon Arc Accelerated Weathering for DuPont Hytrel® 40D Polyester Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-6 Material Properties Retained after Carbon Arc Accelerated Weathering for DuPont Hytrel® 5556 Polyester Thermoplastic Elastomer with Varying Levels of Carbon Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-7 Material Properties Retained and Surface and Appearance after Carbon Arc Accelerated Weathering for DuPont Hytrel® HT-X-3803 and 4056 Polyester Thermoplastic Elastomer with Varying Levels of Carbon Black . . . . . . . . . . . . . . . . . . . . . . 63-8 Soil Burial and Fungus Resistance for DuPont Hytrel® Polyester Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65-1 Ozone Resistance of Kraton® Styrenic Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . 66-1 Properties Retained after Fadeometer Accelerated Weathering for Noveon Estane® 58202 and Estane® 58300 Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . 66-2 Properties Retained after Fadeometer and QUV Accelerated Weathering for Noveon Estane® 58315 Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66-3 Properties Retained after Fadeometer Accelerated Weathering for Noveon Estane® 58315 and Estane® 58863 Urethane Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . 67-1 Material Properties after Florida Outdoor Weathering of Eliokem Chemigum® Nitrile Thermoplastic Elastomer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68-1 Comparison of Ozone Resistance and Weather Resistance for a Few Thermoset Elastomers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-1 Color Pigments Recommended for Use in Hypalon® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-2 Material Properties Retained and Color Change after Outdoor Weathering and Accelerated Weathering of DuPont Elastomers Hypalon® Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-3 Material Properties Retained and Color Change after Arizona Outdoor Weathering for DuPont Elastomers Hypalon® 40 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . .

xxix

294 295 295 296 297 298 302

303 304

305 306

307

308 309 314 317 318 319 324 326 330

332 333

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70-4

Material Properties Retained and Color Change after Florida and Delaware Outdoor Weathering for Wire Cable Compound DuPont Elastomers Hypalon® 40 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-5 Surface and Appearance and Mildew Resistance after Texas and California Outdoor Weathering for Green Hose Cover Compound DuPont Elastomers Hypalon® 40 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-6 Material Properties Retained and Surface and Appearance after Florida Outdoor Weathering for White DuPont Elastomers Hypalon® 40 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-7 Material Properties Retained and Surface and Appearance after Delaware Outdoor Weathering for DuPont Elastomers Hypalon® 20 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-8 Material Properties Retained and Surface and Appearance after Panama Outdoor Weathering for Pond Liner Formulation DuPont Elastomers Hypalon® 45 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-9 Material Properties Retained and Color Change after EMMA and EMMAQUA Accelerated Outdoor Weathering for Black DuPont Elastomers Hypalon® 40 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70-10 Material Properties Retained and Color Change after Xenon Arc Weatherometer Exposure for Black DuPont Elastomers Hypalon® 40 Chlorosulfonated Polyethylene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-1 Mechanical Properties Retained after Outdoor and Accelerated Outdoor Weathering of White, Randomly Selected, Unstrained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . 72-2 Mechanical Properties Retained after Outdoor and Accelerated Outdoor Weathering of Black, Weather Resistant, Unstrained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . 72-3 Mechanical Properties Retained after Outdoor and Accelerated Outdoor Weathering of Black, Randomly Selected, Unstrained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . 72-4 Mechanical Properties Retained and Color Change after Outdoor Weathering, Accelerated Outdoor Weathering by EMMAQUA, and Accelerated Weathering with a Xenon Arc Weatherometer for Black Exxon Vistalon EPDM Terpolymer . . . . . . . . . . . . . . 72-5 Material Properties Retained and Color Change after Arizona Outdoor Weathering With and Without Water Spray Added for Black Exxon Vistalon 5600 EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-6 Mechanical Properties Retained and Color Change after Arizona Outdoor Weathering of Black Exxon Vistalon 5600 EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-7 Material Properties Retained after Florida Outdoor Weathering and Accelerated Outdoor Weathering by EMMA for Black, Weather Resistant, Strained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-8 Material Properties Retained and Color Change after Florida Outdoor Weathering With and Without Water Spray Added for Black Exxon Vistalon 5600 EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-9 Material Properties Retained and Surface and Appearance after Florida Outdoor Weathering of Weatherable EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-10 Mechanical Properties Retained after Florida Outdoor Weathering and Accelerated Outdoor Weathering by EMMA for Black, Randomly Selected, Strained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-11 Mechanical Properties Retained after Florida Outdoor Weathering and Accelerated Outdoor Weathering by EMMA for White, Randomly Selected, Strained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

334

335

336

337

338

339

340 349 350 351

352

353 354

355

356 357

358

359

List of Graphs and Tables 72-12 Material Properties Retained and Color Change after Florida Outdoor Weathering of Black EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-13 Material Properties Retained and Color Change after Accelerated Outdoor Weathering by EMMA and EMMAQUA and Accelerated Weathering in a Xenon Arc Weatherometer for Black Exxon Vistalon 5600 EPDM Terpolymer . . . . . . . . . . . . . . . . . . . 72-14 Mechanical Properties Retained and Color Change after Arizona Accelerated Outdoor Weathering by EMMA and EMMAQUA for Black Exxon Vistalon 5600 EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-15 Mechanical Properties Retained after Accelerated Weathering in a UV-CON and a Xenon Arc Weatherometer for White, Randomly Selected, Strained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-16 Mechanical Properties Retained after Accelerated Weathering in a UV-CON and a Xenon Arc Weatherometer for White, Randomly Selected, Unstrained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-17 Mechanical Properties Retained after Accelerated Weathering in a UV-CON and a Xenon Arc Weatherometer for Black, Weather Resistant, Strained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-18 Mechanical Properties Retained after Accelerated Weathering in a UV-CON and a Xenon Arc Weatherometer for Black, Randomly Selected, Unstrained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-19 Mechanical Properties Retained and Color Change after Accelerated Weathering in a Xenon Arc Weatherometer of Black Exxon Vistalon 5600 EPDM Terpolymer . . . . . . . . 72-20 Mechanical Properties Retained after Accelerated Weathering in a UV-CON and a Xenon Arc Weatherometer for Black, Weather Resistant, Unstrained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-21 Mechanical Properties Retained after Accelerated Weathering in a UV-CON and a Xenon Arc Weatherometer of Black, Randomly Selected, Strained EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-22 Surface and Appearance and Ozone Resistance of Exxon Vistalon EPDM Terpolymer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72-23 Surface and Appearance and Ozone Resistance of EPDM Terpolymer . . . . . . . . . . . . . . . 73-1 Mechanical Properties Retained and Color Change after Arizona Outdoor Weathering and Accelerated Outdoor weathering by EMMAQUA and Xenon Arc Accelerated Outdoor Weathering for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . 73-2 Material Properties Retained, Hardness Change, and Color Change after Arizona and Florida Outdoor Weathering for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . 73-3 Mechanical Properties Retained and Color Change after Arizona Outdoor Weathering and Arizona Outdoor Weathering with Spray for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73-4 Material Properties Retained, Hardness Change, and Color Change after Arizona Outdoor Weathering and Arizona Outdoor Weathering with Spray for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73-5 Material Properties Retained, Hardness Change, and Color Change after Florida Outdoor Weathering and Florida Outdoor Weathering with Spray for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73-6 Material Properties Retained, Hardness Change, and Color Change after Xenon Arc Accelerated Weathering and EMMA and EMMAQUA Accelerated Outdoor Weathering for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

xxxi

360

361

362

363

364

365

366 367

368

369 370 371

374 375

376

377

378

379

xxxii 73-7

73-8 73-9 74-1 75-1 75-2 75-3 75-4 76-1 77-1 77-2 A2-1

The Effects of UV Light and Weather on Plastics and Elastomers Mechanical Properties Retained and Color Change after EMMA and EMMAQUA Arizona Accelerated Outdoor Weathering for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Properties Retained and Color Change after Xenon Arc Accelerated Weathering for Black DuPont Neoprene® W Neoprene Rubber . . . . . . . . . . . . . . . . . . . . . . Ozone Resistance after Exposure of Black DuPont Neoprene® W Neoprene Rubber . . Ozone Resistance of Japanese Synthetic Rubber JSR BR Polybutadiene Rubber . . . . . Ozone Resistance of Goodyear Natsyn® 2200 Polyisoprene Rubber as per the Annulus Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ozone Resistance of Goodyear Natsyn® 2200 Polyisoprene Rubber as per ASTM D1171 Loop Ozone Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ozone Resistance of Goodyear Natsyn® 2200 Polyisoprene Rubber as per the Static Strip Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ozone Resistance of Goodyear Natsyn® 2200 Polyisoprene Rubber as per the Kinetic Stretch Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gloss Retained after Xenon Arc Accelerated Weatherometer Exposure of Polyurethane Rubber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Change in Mechanical Properties after Florida and Michigan Outdoor Weathering for Dow Corning Silastic® Silicone Rubber as per ASTM D518, Method A . . . . . . . . . . . . . . . Change in Mechanical Properties after Florida and Michigan Outdoor Weathering for Dow Corning Silastic® Silicone Rubber as per ASTM D518, Method B . . . . . . . . . . . . . . . Comparative Properties and Performance Chart—Coil Coating Topcoats . . . . . . . . . . . . .

380 381 382 384 386 387 388 389 392 393 394 399

Introduction How to Use This Book This data bank publication presents the results of weathering exposure for more than seventy-seven families of plastics and elastomers. Each chapter represents a single generic family. Data appears in textual, tabular, and graphical forms. Textual information is useful as it is often the only information available or the only way to provide an expansive discussion of test results. This is especially true in the case of weathering data where many results are qualitative. Tables and graphs provide detailed test results in a clear, concise manner. Careful study of a table or graph will show how variations in material, exposure conditions, and test conditions influence a material’s physical characteristics. Each table or graph is designed to stand alone, be easy to interpret, and provide all relevant and available details of test conditions and results. The information’s source is referenced to provide an opportunity for the user to find additional information. The source information might also help to indicate any bias which might be associated with the data.

Weatherability Weather Defined Webster’s dictionary defines weathering as a “Noun. Action of the elements in altering the color, texture, composition, or form of exposed objects. Weather: to expose to air; to season, dry, pulverize, discolor, etc., by exposure to air.” In essence, weathering is the natural tendency of materials to return—corrode, oxidize, chalk, permeate, delaminate, depolymerize, flex crack, etc.—to their elemental forms. Variations in Natural Weathering Weathering is variable by region, season, year, etc. Exposure to a subtropical climate such as Florida

can easily be twice as severe as exposure in northerly regions. This is due to the increase in UV radiation caused by the higher average sun angle and exceptionally moist climate. On the other hand, Arizona may offer an increased UV radiation degradation, but has a much lower rate of deterioration due to humidity. Seasonal variations such as higher temperature and increased UV radiation (due to higher sun angle in the summer) can cause summer exposure to be two to seven times as severe as winter exposure in the same place. Variations in weather can change from year to year making one year twice as severe as the last. Natural (outdoor), accelerated outdoor, and accelerated machine testing attempt to recreate weathering and its variability, usually under conditions more severe than normally encountered. Testing for Weatherability The primary purpose served by examining data on weathering of materials is to predict any potential changes of both physical properties and appearance of a part made from those materials. Data on the aging behavior of plastics are acquired through accelerated tests and/or actual weather exposure. These tests serve as a means for comparison of materials and can also be exploited to determine the ability of the material to serve its function when formed into parts and used in a particular environment. Comparisons between materials are made by measuring the retention of properties (e.g., impact strength, gloss, tensile strength, yellowness index) significant to the application as a function of exposure time. The demand for new products has shortened the time available for determining the durability of a particular material. Therefore, accelerated weathering is increasingly used in an attempt to predict the long-term environmental effects in less time than the real-time working life expectancy. Natural sunlight is not standard; there are variations in clouds, smog, angle of the sun, rain, industrial environments, etc. Likewise options and

2


approaches to the testing of plastic materials and their additives vary among individuals and change as theory becomes application. As a result, there are differing opinions as to the validity of testing, both with natural exposure and under accelerated or laboratory conditions. Testing and reliance on test results is necessary in the product development process to determine the durability of materials in particular applications. An accelerated weathering method correlates with real-time exposure testing when specific defects can be generated in a material with an acceptable precision in a repeatable, shorter interval. Many manufacturers and suppliers worldwide find the correlations acceptable and have adopted test specifications for accelerated and artificial weathering. The factors that influence the degree of weathering are: •

Solar radiation (usually UV)

•

Moisture (dew, humidity, rain)

•

Heat (surface temperature of the material)

•

Pollutants (ozone, acid rain)

•

Salt water

Because these factors vary so widely over the earth’s surface, the weathering of materials is not an exact science. It is virtually impossible to rank the degenerative power of temperature, moisture, and UV radiation. Most materials are weathered by a combination of these factors, but some are degenerated by moisture alone or UV radiation alone. Before one can determine the appropriate test procedure for a particular material, it is important to become familiar with the elements of natural weathering, how they work, and how they may work together to cause adverse effects on the durability of a given part.

or reinforcing action, has been demonstrated many times in studies on durability. Radiation UV wavelengths from sunlight are an important component in outdoor degradation. The energy from sunlight is mainly visible light (700–400 nm), infrared (manifested as heat), and UV light (400– 10 nm).∗ Although UV radiation amounts to only 3% of the total radiation that reaches the earth, it is energetic enough to cause chemical reactions, weathering of polymers, and fading of certain dyes. The energy contained in UV light is capable of directly rupturing polymer chains (chain scission), and, in the presence of oxygen, UV radiation causes oxidation of plastics. The wavelengths that cause the most damage to polymers are in the UV range, 290–400 nm. At the shortest wavelengths in the UV region, the photon energy is of the same order of magnitude as the energies of the bonds in common polymers. The intensity of this short-wavelength radiation is strongly dependent on season and location.[1] The infrared (felt as heat) portion of sunlight warms plastics and accelerates the harmful effects of UV light. In the continental United States, weathering conditions are several times more severe in summer than in winter. This is partly due to the increase in the amount of UV light that penetrates the atmosphere and reaches the ground in the summer and partly due to higher temperatures.[2] The solar UV radiation spectrum is divided into three ranges. UV-A is the energy with wavelengths between 400 and 315 nm. UV-B is the spectrum from 315 to 290 nm. UV-C includes solar radiation below 290 nm. The wavelength regions of UV radiation and their characteristics relative to degradation of materials are listed below. Wavelength Regions of UV Radiation

Elements of Weather The process of weathering includes the action of elements in addition to the effects of radiation. The combination of these factors produces an effect greater than the sum of the individual effects; degradation due to radiation is accelerated when the other elements operate at the same time. This synergism,

UV-A 400–315 nm

∗ Nanometers

Always present in sunlight; 400 nm upper limit for UV-A is the boundary between visible light and UV light; energy at 315 nm boundary

(nm) are commonly used for measuring wavelengths. 1 nm = 10−9 m.

3

Introduction begins to cause adverse effects and pigmentation changes in human skin and some polymers. UV-B 315–290 nm

Includes the shortest wavelengths found at the earth’s surface; responsible for severe polymer damage; absorbed by window glass; UV light absorption by ozone varies with solar altitude; 290–315 nm is completely absorbed at altitudes below 14◦ , at 19◦ solar cutoff is 310 nm, at 40◦ solar cutoff is 303 nm, at solar altitudes between 60◦ and 90◦ maximum UV-B reaches the earth’s surface with a solar cutoff at approximately 295 nm.

leaves the material vulnerable. The severity of moisture attack increases dramatically with increasing temperature.

Radiation and Water

UV-B wavelengths cause the most damage to polymeric materials.

Radiation and water, two components of weather, tend to operate at different times. However, materials can be irradiated after having been wet by rain or when they have high moisture content from overnight high humidity. In this situation, radiation can accelerate the effect of water, and vice versa.[3] It is also possible for radiation to raise the temperature of a material to the point where solution or hydrolysis can occur. In the case of plasticizers, vinyl coatings and plastics may delaminate if they are appreciably soluble in water at elevated temperatures. Strength of polyester laminates can also be reduced through attack by water either on the resin itself or on the bond between the resin and the glass fiber. These actions are not so marked as in actual immersion in hot water, but they can contribute to the degradation process.[3]

Moisture

Radiation and Oxygen

A high incidence of moisture has important implications on the durability of a part. It is often the case that water is not destructive in itself, but water causes damage by bringing oxygen into intimate contact with the material and thereby promotes oxidation. Generally, the potential for degeneration from dew exceeds that associated with rain. In Florida, materials are exposed to outdoor wetness an average of eight hours per day, or about 2900 hours of moisture per year. Materials are wet from dew or condensation more frequently and for longer durations than from rain. To condense dew, a material must be cooler than the dew point temperature of air. This usually occurs during night when solid objects lose their heat through radiation. The fact that materials are exposed primarily to dew and not rain affects the type of degradation that will occur. Dew is saturated with oxygen and lies on materials for hours. The resulting internal oxidation and leaching of soluble additives

A natural weathering combination that has probably even greater effect is oxygen and radiation, referred to technically as photo-oxidation. Materials subjected to oxygen are degraded much faster in the presence of radiation than in its absence. For example, discoloration of polystyrene occurs more rapidly when irradiation takes place in air or oxygen. With saturated polymers there is little damage from oxygen at room temperature if UV radiation is absent.[3]

UV-C 290–100 nm

The UV-C range is a sharp cutoff of solar radiation at the earth’s surface due to complete absorption by ozone; found only in outer space.

Reducing the Effect of Radiation Because the effects of heat, oxygen, and radiation can be severe, attempts are made to reduce susceptibility to one or more of the factors. It is difficult to remove the potential exposure to heat and oxygen in an environment, and radiation is often the most important of the three factors. Thus, there are several options other than additives that could reduce exposure of a polymer to radiation.[3]

4

The Effects of UV Light and Weather on Plastics and Elastomers •

A transparent polymer does not absorb radiation, therefore, minimizing the effects of the radiation. In the real world it is difficult to achieve complete transparency as evidenced by polyethylene, which is transparent to UV radiation but readily degrades upon exterior exposure.[3]

•

Manufacture polymers whose bond strengths exceed the energy available in solar radiation. The potential for success of this method is limited by the fact that most such combinations form simple compounds instead of polymerizing. These materials are often readily decomposed by water or oxygen. Silicones are an example of this polymer type with a silicon-oxygen backbone and organic side groups. “The siliconoxygen bond is only broken by radiation of wavelengths below 270 nm, and this is not received at the earth’s surface. The organic groups are necessary for the material to have the properties required of a polymer; without them the material is quartz or silica—SiO2 . Fluorocarbon polymers are another example. Although fluorine is not part of the molecular backbone, the high strength of the fluorine-carbon bonds in the side groups contributes markedly to their excellent exterior durability.”[3]

•

“The final and most common procedure in minimizing the effect of radiation is to prevent the polymer from absorbing it. If the material does not have to be transparent this can readily be accomplished through the incorporation of pigments that reflect radiation or absorb it preferentially. Reflection usually occurs at the pigment surfaces within the resin so that the radiation has to pass through the top layers twice. Some degradation can, therefore, occur at the surface, and this is why materials frequently lose gloss on exposure. For complete absorption to take place the pigment must be black. Incorporation of black pigment is very effective, as shown by the increase in durability

of polyethylene from one year to 20 years with the addition of 1 per cent carbon black. The color, however, is not always acceptable. For other colors titanium, zinc or iron oxides can be used, but higher concentrations are required.”[3] Surface Temperature and Thermal Degradation Surface temperature is the most variable factor in weather. An automobile driven at 55 mph on a highway will attain a surface temperature near ambient. The same car, locked and parked in direct sunlight, can reach a surface temperature 30◦ C above ambient. At night, with no wind and a clear sky, the surface temperature can drop 8◦ C below ambient. Color is also a contributing factor in surface temperature. White materials typically attain a temperature 10◦ C–15◦ C lower than black materials. It is difficult to match outdoor temperature differences between dark and light materials in the laboratory. For example, the introduction of air for heating and cooling will reduce temperature differences between colors. While temperature is an important factor in weathering, it is also important to note that not all materials show increased degradation with increased temperature. Thermal degradation of polymers, molecular deterioration as a result of overheating, can result from exposure to the elements. At high temperatures the components of the long-chain backbone of the polymer begin to separate (molecular scission) and react with one another to change the properties of the polymer. Thermal degradation generally involves changes to the molecular weight (and molecular weight distribution) of the polymer. Significant thermal degradation can occur at temperatures much lower than those at which mechanical failure is likely to occur.[4]

Material Properties Post-Exposure The many concurrent chemical processes taking place in polymers exposed to UV radiation result in several different modes of damage, each progressing at a different rate. It is usually the critical first-observed damage process that determines the

5

Introduction

useful service life of the product. For example, a polyvinyl chloride (PVC) window frame exposed to sunlight undergoes discoloration, chalking, loss of impact strength, and a reduction in tensile properties as well as a host of other chemical changes. It is, however, the discoloration (or the uneven yellowing) of the window frame that generally determines its service life. However, with continued use, other damage such as chalking and eventually loss of impact resistance (leading to cracking) can occur making the product even more unacceptable. The two critical modes of photodamage applicable to most natural and synthetic materials are yellowing discoloration and loss of mechanical integrity.[5] Exposure of many plastics to UV radiation causes a loss in their mechanical properties and/or a change in their appearance. Typical property changes include: •

Reduced ductility and embrittlement

•

Chalking

•

Color changes

•

Yellowing

•

Cracking

Photodegradation causes a loss of strength, impact resistance, and mechanical integrity of plastics exposed to UV radiation. These changes in mechanical properties reflect the result of polymer chain scission (and/or cross-linking). The molecular changes of these materials can be characterized through the study of solution viscosity and the gel permeation characteristics. The embrittlement produced by UV radiation exposure is often evaluated by measuring the impact resistance (toughness) of the material.[5] Deterioration in appearance produced by UV radiation exposure can be evaluated by measuring color shift and gloss. The observed color shift, E, may be affected by the change in gloss. While the determination of gloss is straightforward, techniques for evaluating color shift may vary considerably. A very sensitive method of quantifying the change in the mechanical properties of polymers brought about by the effects of weathering is to determine the penetration energy on weathered specimens. If the unirradiated reverse side of the specimens is impacted, the irradiated front side experiences a sudden tensile stress, so that even the

slightest deterioration gives a clear reduction in the measured values. This test is therefore an excellent indicator of weathering resistance. In contrast, if the impact is on the irradiated side, as most frequently happens in practice, a reduction in toughness is only observed after much longer exposure times. Measurable reductions in the values of properties such as breaking stress and modulus of elasticity are also seen only at a much later stage.[6]

UV Additives and Stabilizers UV sensitivity is based on complex photolytic and photo-oxidative mechanisms that lead to material degradation as a result of chain scission. Reactive radicals are produced by the energy-rich UV light. In the presence of oxygen the plastics are oxidized (photo-oxidation). Two methods of UV stabilization are commonly used: UV absorbers (e.g., benzotriazoles) and UV stabilizers (e.g., hindered amines). Hydroxybenzotriazoles preferentially absorb light in the 300– 400 nm wavelength range. They dissipate the light energy by a tautomeric process, which protects the polymer by preventing it from absorbing harmful radiation. Hindered amines, on the other hand, act as radical scavengers. Through the formation of nitroxyl radicals, hindered amines terminate and deactivate alkyl radicals and peroxy radicals, which are known to participate in the photo-oxidation process. While functioning as radical scavengers, the stabilizing species (the nitroxyl radical) is regenerated and continues to scavenge.[7] Effective light absorbers such as benzotriazoles, benzophenones, and phenyl esters as well as hindered amine light stabilizers (HALS) are presently used in plastics formulations intended for outdoor use (usually at a 0.05–2.0 wt% level). Improved stabilizers are introduced into the market periodically.[5] In conventional light stabilization by pigments such as carbon black and titanium dioxide, the UV radiation is absorbed by the pigments and chain scission of the polymer is prevented. The soluble light stabilization systems are combinations of UV absorbers and radical interceptors. UV absorbers convert UV light into harmless thermal energy. Radical interceptors or HALS react with spontaneously forming radicals to form harmless derivatives.

6


UV Absorbers UV absorbers or stabilizers are most efficient when used in materials that have a thick cross section because the amount required is a function of concentration and thickness. Thus, a plastic 20 mils (0.5 mm) thick might be stabilized with 0.5% absorber but requires 1% at 10 mils (0.25 mm) and 2% at 5 mils (0.125 mm). This relation is not strictly linear; effectiveness is reduced at higher concentrations so that more is required than calculated from the relationship.[6] UV absorbers can be rather specific in their action—even absorbers that are closely related chemically may show large differences in effectiveness with different resins. As a result, comprehensive tests are needed to determine the type and amount of absorber to be used with any given polymer. It must also be appreciated that absorbers do not last indefinitely, but are slowly degraded, and that the absorption they are intended to prevent will ultimately occur.[6]

Hindered Amine Light Stabilizers With organic light stabilizers such as hindered amines, increasing the stabilizer level in the

composition will have little or no impact on processibility of the resin. The cost, however, will be significantly affected because the contribution of the stabilizer cost to the total cost of a product such as greenhouse films can be as much as 30%.

Antioxidants Antioxidants are also commonly used to aid in UV stabilization. Although antioxidants are neither light stabilizers nor UV absorbers, they often improve the overall weatherability of the polymer when used in combination with a UV absorber or light stabilizer. They do this by interrupting the free-radical process during photo-oxidation.[7]

UV Inhibitors UV inhibitors, commonly referred to as UVIs, are chemical compounds that absorb UV light and disperse the energy contained in UV radiation in a form that is less harmful to the plastic. Most materials synthesized for the purpose of being used as UVIs are transparent and essentially colorless, but there are also some pigments and dyes that function as UVIs.[2]

Test Environments Indoor and Interior Exposure During indoor exposure, products are subjected to UV radiation from fluorescent lights as well as from glass-filtered UV rays transmitted through windows. The type of light source, its energy flux, and its distance from the specimens determine the intensity of the radiation impinging on the surface of the part. Glass of any type acts as a filter on the sunlight spectrum. The shorter, most damaging wavelengths are the most greatly affected. Ordinary window glass is essentially transparent to light above 370 nm. However, the filtering effect becomes more pronounced with decreasing wavelength. Windshield glass is thicker than window glass; it acts as a more efficient filter. Safety features associated with windshield glass (e.g., tinting and plastic) add to the filtering efficiency. Almost all UV light is filtered out

by windshield glass, and the most damaging wavelengths below 310 nm are completely filtered out.

Outdoor Testing Real-time weathering data from natural environment exposure programs remain the standard to which all other weathering data are compared. Three of the most commonly used harsh aging sites are Arizona, Florida, and Japan. Arizona is important because of its high annual radiation and ambient temperature. Southern Florida is unique because of its high radiation combined with high rainfall and humidity. These two areas have become US and international reference climates for gauging the durability of materials since they represent the worst case for applications in the northern hemisphere.

8


With all outdoor tests it is important to be aware of bias introduced by the choice of location. Details about a few representative test sites are listed in the chart above. In Miami, Florida, there are approximately 110 sun hours per month. This is a total of 1200–1300 sun hours per year. With a 45◦ due south exposure, test specimens receive approximately 150,000 langleys per year.

Accelerated Outdoor Tests In outdoor tests, the usual standard procedure calls for specimen exposure on racks facing due south at an angle of 45◦ . These are conditions that offer a maximum direct sunlight exposure and intensity. This tilt is also preferable since it allows for some drainage and wash off during rains. Sources of radiation for outdoor exposure tests include both direct and reflected sunlight. In a further attempt to accelerate outdoor effects, many studies are conducted in tropical as well as hot, dry climates such as Florida and Arizona in the United States, and Panama, Germany, and Japan to obtain the most wide ranging and severe environments possible. Outdoor accelerated weathering is a relatively recent technique. It relies heavily on technology to follow the track of the sun and to keep the sample at a constant temperature. Equatorial Mount with Mirrors for Acceleration (EMMA): Natural sunlight and special reflecting mirrors are used to concentrate sunlight to the intensity of about eight suns. The test apparatus follows the sun track with mirrors positioned as tangents to an imaginary parabolic trough. The axis is oriented in a north–south direction, with the north elevation having the capability for periodic altitude adjustments. A blower directs air over and under the samples to cool the specimens. This limits the increase in surface temperatures of most materials to 10◦ C (50◦ F) above the maximum service temperature that is reached by identically mounted samples exposed to direct sunlight at the same times and locations without concentration. Exposed periods of 6 and 12 months have been correlated to about 2.5 and 5 years of actual aging in a Florida environment, respectively.

Equatorial Mount with Mirrors for Acceleration Plus Water (EMMAQUA): Natural sunlight and special reflecting mirrors are used to concentrate sunlight to the intensity of about eight suns. In addition to intensifying the power of the sun, a water spray is used to induce moisture weathering conditions. The test apparatus follows the sun track with mirrors positioned as tangents to an imaginary parabolic trough. The axis is oriented in a north– south direction, with the north elevation having the capability for periodic altitude adjustments.Ablower directs air over and under the samples to cool the specimens. This limits the increase in surface temperatures of most materials to 10◦ C (50◦ F) above the maximum service temperature that is reached by identically mounted samples exposed to direct sunlight at the same times and locations without concentration. Exposure to EMMAQUAis considered to be the harshest exposure.

Conventional Aging This test method, which may occur in many different geographic locations (e.g., Florida, Arizona, and Okinawa, Japan), is real-time exposure at a 45◦ tilt from the horizontal. Direct exposures are intended for materials that will be used outdoors and subjected to all elements of weather. Exposure times are generally 6, 12, 24, and 48 months. Location is an important factor in the harshness of this test. The assumption is that test results from a hostile environment will prevail in more moderate conditions. Conventional Aging with Spray This test method, which may occur in many different geographic locations (e.g., Florida, Arizona, and Okinawa, Japan), is real-time exposure at a 45◦ tilt from the horizontal with a water spray used to induce moisture weathering conditions. The introduction of moisture plays an important role in improving both the relevance and reproducibility of the weathering test results. The purpose of wetting is twofold. First, the introduction of water in an otherwise arid climate induces and accelerates some degradation modes that do not occur as rapidly, if at all, without moisture. Second, a thermal shock causes a reduction in specimen surface

9

Test Environments temperatures, as much as 14◦ C (57◦ F). This results in physical stresses that accelerate the degradation process. Spray nozzles are mounted above the face of the rack at points distributed to ensure uniform wetting of the entire exposed area. Distilled water is sprayed for four hours preceding sunrise to soak the samples, and then twenty times during the day in 15-second bursts. Direct exposures are intended for materials that will be used outdoors and subjected to all elements of weather. Exposure times are generally 6, 12, 24, and 48 months. Location is an important factor in the harshness of this test. With all outdoor tests it is important to be aware of bias introduced by the choice of location. Humidity Variations Atmospheric humidity is very high in Florida, very low in Arizona, and variable in Tennessee. Results obtained at these stations should be indicative of performance to be expected under comparable conditions of latitude, elevation, temperature, and humidity throughout the world.[2] Solar Radiation Weathering conditions are more severe in Arizona and Florida than in Tennessee, and generally more severe in Arizona than in Florida. Solar radiation in Phoenix averages more than 185,000 langleys per year on a horizontal surface; the average daytime high temperature exceeds 38◦ C (100◦ F) during the summer months.[2]

Sample Mounting Direction Experimental weathering is done in an open location with the samples facing south and inclined northward at an angle of 45◦ from the vertical, exposing the specimens to almost the maximum possible sunshine with a fixed mounting in the central northern latitudes. (This mounting is specified in Test Method D1435 published by the American Society for Testing and Materials.) Less severe exposure would increase the life expectancy of the material over that indicated by the test results. For example, a meter cover mounted on the east wall of a house might receive less than half the available sunshine, and its useful life should be substantially longer than that of a test specimen. Differences in weathering due to different mounting directions are accentuated by the fact that the rays of the midday sun contain much more energy than the early morning and late afternoon rays.[2]

Artificial Accelerated Tests Artificial weathering devices, tests that use artificial light sources, are used to measure the resistance of materials to weather degradation. These tests provide reliable data in a shorter period of time than outdoor testing. Light sources for the accelerated tests include filtered long arc xenon, fluorescent metal halide lamps, and carbon arc. Less commonly used light sources include mercury vapor and tungsten lamps. Each light source has its own inherent benefits of which a weathering experimenter must be aware.

Conditions for Reproducing Natural Weathering Stresses in the Laboratory UV Conditions UV-B emission with minimal emission below 290 nm

Water Conditions Condensed from vapor phase; pH approximately 4.0–6.0; saturated with O2

Exposure Duration

No theoretical maximum or minimum; practical minimum of three to four hours

Time and temperature interact; practical limits of four to twenty hours

Temperature

55◦ C–80◦ C as required to duplicate service temperature

60◦ C sometimes causes abnormal effects; 50◦ C for eight hours can cause problems; 40◦ C is safe but slower

Quality

10


Xenon Arc Xenon arc is a precision gas discharge lamp sealed in a quartz tube. Through a combination of filters used to reduce unwanted radiation, the xenon (long) arc simulates UV and visible solar radiation more closely than any other artificial light source. It is widely preferred as a light source when the material to be tested will be exposed to natural sunlight.[8] Automotive test SAE J1885 is used for testing interior automotive materials and calls for xenon arc exposure with quartz inner and borosilicate outer filters. This filter combination transmits short-wave UV radiation as low as 275 nm. Automotive test SAE J1960 is used to evaluate exterior automotive materials by accelerated means. The test uses a quartz/borosilicate-S filter combination. Most engineers involved with this test state that 2500 kJ/m2 is approximately two years of Florida testing. However, the spectral power distribution (light intensity vs. wavelength) of the SAE J1960 test method does not exactly match actual Miami sunlight and can be a nonpredictive test for some materials. Some automotive companies use different optical filter combinations (Boro-S/Boro-S or CIRA/Soda Lime) that more closely match true Miami solar radiation. In addition, the comparison based on a single factor (solar radiant energy) does not take into account the other weathering factors such as heat, moisture, etc., and their synergistic effects, which magnify the effects of solar radiation.[8] Test methods specifying xenon arc include ASTM D2565, D4459, and G155, SAE J1885 and SAE J1960, and GE Co. Highly Accelerated Weathering Protocol for all outdoor applications.

Fluorescent or QUV The QUV test procedure simulates long-term outdoor exposure to sunlight, rain, and dew by exposing materials to alternating cycles of UV-A or UV-B light and moisture at controlled elevated temperatures. These are the most aggressive components of weathering—UV radiation, moisture, and heat. UV radiation within a desired UV wavelength is provided through the use of fluorescent lamps.

Moisture is provided by forced condensation and temperature is controlled by heaters.[9] Although UV light makes up only about 5% of sunlight, it is responsible for most of the damage caused to durable materials exposed outdoors. To simulate the damage caused by UV rays, it is not necessary to reproduce the entire spectrum of sunlight. In many cases it is only necessary to simulate the short-wavelength UV. Each type of lamp differs in the total amount of UV energy emitted and in its spectrum. Fluorescent UV lamps are usually categorized as UV-A or UV-B lamps, depending on the region into which most of their output falls.[10] UV-A lamps are useful for comparing different types of polymers. Because UV-A lamps do not have any UV output below 295 nm, they do not degrade materials as quickly as UV-B lamps. UV-A lamps usually provide good correlation with actual outdoor weathering.[10] UVA-340 lamps provide the best possible simulation of sunlight in the critical short wavelength from 365 nm down to the solar cutoff of 295 nm. It is most useful in comparison tests of different formulations.[10] UVA-351 lamps simulate the UV portion of sunlight filtered through window glass. It is most useful for simulating interior applications.[10] UV-B lamps are used for fast, cost-effective testing of durable materials. All UV-B lamps emit shortwavelength UV below the solar cutoff of 295 nm. Although this short-wave UV accelerates testing, it can sometimes lead to anomalous results.[10] UVB-313 is the most widely used UV-B lamp for testing very durable applications. It is especially useful to maximize acceleration when testing very durable applications like automotive coatings and roofing materials.[10] QFS-40 is the original QUV lamp. These lamps are also known as FS-40 or FS-40 UVB. It has demonstrated good correlation to outdoor exposures for gloss retention on automotive coatings and for material integrity of plastics.[10] Tests using fluorescent lamps are useful for relative rank comparisons between materials under specific conditions, but the comparison to service lifetime performance or correlation to outdoor exposures may not be valid. The best use of the UV lamps is for general screening tests such as checking for

11

Test Environments

gross formulation errors with an artificially harsh exposure.[8] Test methods specifying the QUV UV-340 lamp include ASTM D4329 and D4587, ISO 4892, and SAE J2020. Carbon Arc or Fadeometer Carbon arc devices generally use two lamps (twin arc). The flame carbon arc is open or enclosed (ECA), encased in a borosilicate glass cover that acts as a filter for low-wavelength radiation. The spectral emission of the flame carbon arc, a significant amount of which is below 300 nm, bears little resemblance to sunlight. The two strong emission bands of an enclosed carbon arc peak at 358 and 386 nm and are much more intense than natural sunlight. Therefore, carbon arc testing will have a weaker (than actual outdoor) effect on materials that absorb only short-wavelength radiation. In addition, ECA results will have a stronger (than actual outdoor) effect on materials that absorb long-wavelength UV and visible light.[8] Sunshine Carbon Arc provides a better match to natural sunlight than ECA at longer wavelengths. However, Sunshine Carbon Arc provides more radiation at wavelengths below 300 nm than natural sunlight.[8] Due to the fact that some materials absorb primarily short wavelengths and some materials absorb primarily longer wavelengths, carbon arc light sources can distort the relative light stability of tested materials, especially when compared to samples exposed to actual solar radiation.[8] “While good correlation with outdoor exposures has been reported for some materials whose weathering mechanisms are appropriate for these limited spectrum sources, this technology has largely been replaced with fluorescent UV or xenon arc systems.” Carbon arc testing continues to be used to test material durability in some applications.[8]

Test Results Failures of exposed specimens are measured or recorded in several different ways including:[11] •

Time-To-Fifth Spot: Clear films show incipient failure by development of

very small random brown spots characteristic of UV degradation. The “first failure” is recorded as the time to the fifth spot on these clippings. The first few spots may appear fortuitous in some cases and unrelated to general failure. •

Final Failure: Spotting and accompanying embrittlement continue until the film loses integrity and tends to tear from the rack or until it is completely brown. This is the “final failure” time.

•

Brittleness Temperature: The brittleness temperature is measured before exposure and then on the samples as they are received at regular intervals from the exposure site. Measurements are run up to 22◦ C. The ASTM 179062 (Masland Cold Crack) method, with the use of semi-micro specimens, is followed in determining brittleness temperatures.

•

Elongation: Elongation is measured on the samples before exposure. As the samples are received from the testing site, their elongations are again measured.

Notes on Variability in Testing and Results Similar test methods can yield test results that vary widely. When comparing results, the user should take into consideration that factors such as test sites, time of year, pollution counts, and sample conditioning, to name a few, can have a huge impact on test results. For instance, at Florida test sites, results can vary widely due to an increase in wetness caused by proximity to a pond or other sources of moisture or dew, or by proximity to woods that shield the drying effects of wind. Another example is variation in sample mounting and its effect on the period of degradation. Plywood backed samples, for instance, get much hotter in direct sunlight than unbacked samples and they are wet for up to twice as long. The “synergistic” effect of UV radiation with moisture is an important area in assessing the validity

12


of accelerated testing and its correlation to the natural weathering process. Much of the weathering literature focuses on the interaction between morning dew and UV radiation. While it is clear that this effect can be reproduced in a laboratory situation, it is not clear that it occurs under actual exposure conditions. The situation is reproduced with devices such as UV-CON and EMMAQUA. However, under normal outdoor exposure, sunlight will probably dry materials before the sun elevation reaches a point where UV-B is transmitted through the atmosphere. Laboratory conditions must be closely matched to actual weathering situations and it is recommended that you carefully consider your own situation in comparing it to the test conditions and data presented in this book.

Color Stability UV light stability of pre-colored resins is often not the same for clear or natural resins. Color stability

depends on many factors, so actual performance will depend on lighting conditions, length of time exposed per day, proximity of material to light sources and windows, choice of color pigments, and other factors. In general, there are two approaches to light stabilization. In the conventional method, light stabilization is achieved with pigments such as carbon black and titanium dioxide. If special requirements are imposed on the material or if a special color is required, then additional light stabilizers and additives are required. When inorganic opacifiers such as titania or carbon black are used with resins such as PVC, for instance, higher levels will affect processibility, power consumption, and even the lifetime of processing equipment, due to increased melt viscosity.[5]

Chapter 1

Acrylonitrile-Butadiene-Styrene Category: Engineering resin. General Description: Acrylonitrile-butadienestyrene (ABS) is a thermoplastic styrene copolymer produced from acrylonitrile, butadiene, and styrene. •

BASF Terluran® is a two-phase polymer blend ABS. A continuous phase of styrene-acrylonitrile (SAN) copolymer gives the materials rigidity, hardness, and heat resistance.[4]

Weathering Properties When ABS is used for extended periods of time in outdoor locations or under fluorescent light, discoloration or distinctive degradation of properties will occur. The cause of weathering-related ABS problems is light-induced degradation of polybutadiene, and as a result of this, the contribution of the rubber to improved impact strength is diminished. This type of degradation is restricted to surface layers.[12] Prolonged exposure to the weather, especially direct sunlight, will cause significant changes in both the appearance and the mechanical properties of ABS plastics. Terluran® is stabilized to inhibit aging caused by atmospheric oxygen and elevated temperature. This stabilization allows Terluran® parts many

years of service life in indoor applications and even in interior automotive applications where the parts are subjected to considerable UV exposure.[4] Sunlight and atmospheric oxygen will damage the butadiene-containing elastomer component of ABS during long-term exposure resulting in yellowing and reduced impact strength. Although this process can be delayed by the use of dark colors or by stabilization, the preferred material for most outdoor applications is BASF Luran® S, an acrylonitrilestyrene-acrylate (ASA) material, which considerably outperforms ABS in weathering resistance.[4] The effect of exposure to UV radiation on the impact strength of ASA and ABS were compared. Standard specimens were exposed on one side in the Xenotest 1200 and tested per DIN 53453 impact test with a blow struck on the unexposed side. The ABS specimens suffered a very rapid drop in impact strength. The ASA specimen retained its impact strength under these conditions over a longer period of time, about seven times as long.[13]

Stabilization Because of its butadiene component, ABS requires UV stabilizers. Synergistic combinations of benzotriazoles (UV absorbers) and hindered amine light stabilizers (HALS) provide improved light stability.[14]

14


Weathering Properties by Material Supplier Trade Name Table 1-1. Outdoor Weathering of White ABS in Florida

Table 1-2. Outdoor Weathering of ABS in Ludwigshafen, Germany

1: Acrylonitrile-Butadiene-Styrene Table 1-3. Accelerated Indoor Exposure of GE Plastics Cycolac® VW300 ABS by HPUV

Table 1-4. Accelerated Indoor Exposure of GE Plastics Cycolac® KJB ABS to Fluorescent Light

15

16


Graph 1-1. Changes in Material Characteristics due to Photo-Oxidation of ABS.[12] 120

Deterioration (%)

100

80 Luster 60

Impact strength Tensile strength

40

20

0 0

1

2

3

4

5

6

Outdoor Weathering (years) Note: The depth of the degraded layer brought about by weathering is of the order of several hundred micrometers. The reaction to photo-oxidation results in the generation of a thin yellow layer at the surface; this layer prevents the diffusion and permeation of oxygen and, in addition, it blocks out light. Accordingly, any further photo-oxidation at the interior of the component is prevented.

Graph 1-2. Outdoor Weathering Exposure Time vs. Yellowness Index of ABS.

1: Acrylonitrile-Butadiene-Styrene

Graph 1-3. Arizona Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS.

Graph 1-4. Arizona Outdoor Weathering Exposure Time vs. Elongation of ABS.

17

18


Graph 1-5. Arizona Outdoor Weathering Exposure Time vs. Tensile Strength at Yield of ABS.

Graph 1-6. Arizona Outdoor Weathering Exposure Time vs. E Color Change of ABS.


19

Graph 1-7. Arizona, Florida, and Ohio Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS.

Graph 1-8. Florida Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS.

20


Graph 1-9. Florida Outdoor Weathering Exposure Time vs. Drop Weight Impact of ABS.

Graph 1-10. Florida Outdoor Weathering Exposure Time vs. E Color Change of ABS.


21

Graph 1-11. Florida Weathering Exposure Time vs. Chip Impact Strength of ABS (White Rovel Capstock and Acrylic Capstock).

Graph 1-12. Florida Weathering Exposure Time vs. Chip Impact Strength of ABS (Natural Resin).

22


Graph 1-13. Ohio Outdoor Weathering Exposure Time vs. E Color Change of ABS.

Graph 1-14. Ohio Outdoor Weathering Exposure Time vs. Dart Drop Impact Strength of ABS.


23

Graph 1-15. Okinawa, Japan, Outdoor Weathering Exposure Time vs. E Color Change of ABS.

Graph 1-16. Okinawa, Japan, Outdoor Weathering Exposure Time vs. Dynstat Impact Strength Retained of ABS.

24


Graph 1-17. Okinawa, Japan, Outdoor Weathering Exposure Time vs. Elongation at Break Retained of ABS.

Graph 1-18. Okinawa, Japan, Outdoor Weathering Exposure Time vs. Gloss Retained of ABS.


25

Graph 1-19. West Virginia Outdoor Weathering Exposure Time vs. Falling Dart Impact of ABS at −40◦ C.

Graph 1-20. West Virginia Outdoor Weathering Exposure Time vs. Falling Dart Impact of ABS at 23◦ C, −25◦ C, and −40◦ C.

26


Graph 1-21. West Virginia Outdoor Weathering Exposure Time vs. Falling Dart Impact of ABS at 23◦ C.

Graph 1-22. West Virginia Outdoor Weathering Exposure Time vs. Flexural Modulus Retained of ABS.


27

Graph 1-23. West Virginia Outdoor Weathering Exposure Time vs. Flexural Strength of ABS at −40◦ C and 23◦ C.

Graph 1-24. West Virginia Outdoor Weathering Exposure Time vs. Flexural Strength Retained of ABS.

28


Graph 1-25. West Virginia Outdoor Weathering Exposure Time vs. Izod Impact Strength Retained of ABS.

Graph 1-26. West Virginia Outdoor Weathering Exposure Time vs. Tensile Strength Retained of ABS.


Graph 1-27. Sunshine Weatherometer Exposure Time vs. Dynstat Impact Strength Retained of ABS.

Graph 1-28. Sunshine Weatherometer Exposure Time vs. Elongation at Break Retained of ABS.

29

30


Graph 1-29. Sunshine Weatherometer Exposure Time vs. Gloss Retained of ABS.

Graph 1-30. Weatherometer Exposure Time vs. Impact Strength of ABS.


Graph 1-31. Xenotest 1200 Exposure Time vs. Impact Strength of ABS.

Graph 1-32. Accelerated Indoor UV Exposure Time vs. E Color Change of ABS.

31

32


Graph 1-33. Yellowness Index of UVA- and HALS-Stabilized ABS after Outdoor Weathering in Switzerland.[14] 25

Control

Yellowness Index

20

15 0.25% UVA 0.25% HALS 10 0.5% UVA 0.5% HALS 5

0 0

40

80

Exposure Time (kilolangley)

120

Chapter 2

Acrylonitrile-Styrene-Acrylate/ Acrylonitrile-Butadiene-Styrene Capstock General Description: GE Plastics’ co-extrusion of Cycolac® acrylonitrile-styrene-acrylate (ASA) and Geloy® acrylonitrile-butadiene-styrene (ABS) resins allows designers, molders, and manufacturers to take advantage of the best properties of both materials in a single product.[25]

Weathering Properties The multilayering technology allows the weather resistant material to be used as capstock. Capstock is the material used as the additional surface layer applied to the exterior surface of a profile extrusion. Geloy® resin capstock over a Cycolac® substrate provides outstanding weatherability.[25]

Weathering Properties by Material Supplier Trade Name Graph 2-1. Color Change, E, after Arizona, Florida, and New York Outdoor Weathering of GE Plastics Cycolac® /Geloy® Resin Systems Compared to PVC.[15] 25

20

∆E

15

10

5

0 Arizona

Florida

New York

PVC, White

PVC, Brown

C/G, White

C/G, Brown

Chapter 3

Acetal Category: Thermoplastic.

•

Ticona Celcon® , an acetal copolymer, is a crystalline engineering thermoplastic product.

•

Ticona Hostaform® , an acetal copolymer, is a specialty product in the range of engineering polymers. Hostaform LS grades are used for interior applications in a variety of colors with good light fastness and constant mechanical properties. Hostaform® black 10/1570 is used for exterior applications, and is UV stabilized and impact modified.

The wavelength of solar radiation that is harmful to polyacetals is in the range of 290–400 nm.[26] Damage to the material is triggered by absorption of UV light by the material. In the case of Hostaform® , little direct absorption in the critical UV region takes place because of the linkages in the polymer chain. This relatively good UV compatibility of polyacetal is limited, however, by unavoidable system-induced impurities and structural irregularities. And in all those cases where other polymers are incorporated [e.g., to improve the impact strength (blends)], the stability is further reduced. In practice, however, these effects are not noticed because extremely effective light stabilization systems have been developed for Hostaform® .[26] Improved weathering performance (retention of surface appearance as well as mechanical properties) is achieved in the Delrin® x07 series by the use of a selected UV stabilizer package.

•

BASF Ultraform® N 2325 U03, an acetal copolymer, is a UV stable injection molding grade developed specifically for use in outdoor applications, and is available in black only.

Weathering Properties: Colored Material

General Description: Acetal or polyoxymethylene (POM) resins are produced by the polymerization of purified formaldehyde [CH2 O] into both homopolymers and copolymers.

•

DuPont Delrin® , an acetal homopolymer resin, is a thermoplastic engineering polymer manufactured by the polymerization of formaldehyde. DuPont Delrin® x27 UV includes UV stabilization and is a UV resistant grade.

Weathering Properties: General Upon exposure to light, polyacetals that are not UV stabilized display loss of gloss, a change in color, and in some cases, chalking—the formation of a white coating on the surface. This degradation process is accompanied by a decrease in strength.

Colored molded parts show practically no color change or no surface changes after accelerated light exposure tests as per SAE J1885. Parts retain their “new car” appearance and do not show unsightly deposits or otherwise “chalk” during service life when made from Celcon® UV90Z. Celcon® UV colored grades meet standards recently introduced by major domestic car manufacturers requiring plastics in automotive interiors to be free of cadmium-based compounds.[27] Color stability tests using a Xenon Arc Weatherometer to simulate accelerated indoor/ outdoor exposure show that pigmented Celcon® UV90Z significantly outperforms competitive acetal and nonacetal products in resisting color degradation, easily passing the automotive SAE J1885

36


Accelerated Indoor Weathering Test with an average of 0.6 CIELab units color shift (a color shift of more than +3.0 units fails SAE J1885). Celcon® UV90Z gave an average 380% lower color change after almost five times longer light exposure than acrylonitrile-butadiene-styrene, and was also superior to polypropylene and polyesters.[27] Celcon® parts retain a high percentage of their original mechanical properties during accelerated UV aging. After extreme light irradiation of 1240.8 kJ/m2 , Celcon® UV90Z retains almost 100% of its “as-molded” tensile strength, flex strength, flex modulus, and impact strength.[27] Hostaform® S 27072 WS black 10/1570 maintains very good UV stability during both accelerated weathering testing (xenon lamp) and outdoor testing (Florida and the Kalahari Desert).[28] Delrin® 507 BK601 compositions have shown excellent retention of strength properties after twenty years of outdoor exposure in Arizona, Florida, and Michigan. Over this period, essentially no loss of tensile strength occurred, but elongation was reduced to about 40% of the initial test value, with the greatest change in elongation occurring during the first six months of exposure.[29] For outdoor applications involving intermittent exposure, or a service of one to two years, colored Delrin® resins are generally suitable, based on mechanical property retention, because the colorant generally offers some UV-screening protection. High levels of carbon black act as an effective UV screen and are recommended for noncritical outdoor applications.[30] Delrin® x27 UV family of resins are of specially formulated colors, together with an optimized

UV stabilizer system. Delrin® x27 UV is intended for applications where parts are exposed to sunlight through glass, which includes automotive interior components and window hardware.[30] Even with UV-stabilized color compositions, surface dulling and chalking begin in about 6–8 months of exposure in Florida. The chalk may be removed by hand polishing in the early stages of development. If removal is delayed, the chalk layer hardens with time and becomes more difficult to remove.[29]

Weathering Properties: Unpigmented Material Celcon® M90UV or M270UV is recommended for unpigmented, natural, applications. It is white as molded, and provides extremely good protection against UV degradation and yellowing.[27]

Weathering Properties: Elevated Air Temperature Delrin® 500 maintains a tensile strength in excess of 55 MPa for approximately five years at 60◦ C. Test bars molded of Delrin® 500 have been stored for about twenty years in the absence of light at room temperature. After that time tensile strength, elongation at break, molecular weight, and notched Izod impact strength were unchanged, and the bars still retained their luster.[30]

37

3: Acetal

Weathering Properties by Material Supplier Trade Name Table 3-1. Color Differences, E, after Light Exposure for Pigmented Ticona Celcon® UV90Z (GM and Ford Automotive Colors) Material Family

Acetal, POM

Material Grade

Ticona Celcon® UV90Z

Reference Number

27

Exposure Conditions

SAE J1885 1240.8 kJ/m2

Exposure Energy Exposure Time Features

approx. 800 hrs GM Standard Black

GM Garnet Red

GM Very Dark Sapphire

GM Medium Beechwood

Ford Corporate Red

1.00

1.35

0.57

1.50

SURFACE AND APPEARANCE Color Change, E

0.17

Table 3-2. Color Differences, E, after Light Exposure for Pigmented Ticona Celcon® UV90Z Material Family

Acetal, POM

Material Grade

Ticona Celcon® UV90Z

Reference Number

27

Exposure Conditions

SAE J1885 1240.8 kJ/m2

Exposure Energy Exposure Time Features

approx. 800 hrs Black

Light Red

Light Tan

Medium Tan

Brown

0.2

0.2

0.2

0.6

0.2

Medium Gray

Dark Blue

Flame Red

Maroon

0.3

0.5

0.9

1.2

SURFACE AND APPEARANCE Color Change, E Features SURFACE AND APPEARANCE Color Change, E

38


Table 3-3. Color Differences, E, after Light Exposure for Unpigmented Ticona Celcon® M90UV Material Family

Acetal, POM

Material Grade

Ticona Celcon® M90UV

Reference Number Exposure Conditions

27 Initial Value

HPUV

Exposure Time

Xenon Arc ASTM 4459

300 HP Units

200 hrs

600 hrs

1000 hrs

2.62

2.63

2.66

2.89

SURFACE AND APPEARANCE Initial b value

4.08

Color Change, b

Note: b is a color value; lower values mean whiter samples.

Table 3-4. Color Differences, E, after Florida Weathering for Ticona Hostaform® Materials Material Family

Acetal, POM Ticona Hostaform®

Material Grade S 27072 WS 10/1570

C 9021 10/1570

Reference Number

C 9021 LS 10/1570

28

Exposure Conditions

Xenotest 1200 CPS (EDAG) VW PV 3920 (Florida)

Exposure Time

1600 hrs

SURFACE AND APPEARANCE Color Change, E

1.8

2.4

0.8

Table 3-5. Color Differences, E, after Xenotest 1200 for Ticona Hostaform® C 9021 LS Blue 80/4065 Material Family

Acetal, POM

Material Grade

Ticona Hostaform® C 9021 LS Blue 80/4065

Reference Number

26

Exposure Conditions Exposure Time

Xenotest 1200 500 hrs

1000 hrs

1500 hrs

2000 hrs

1.2

1.3

1.6

2.2

SURFACE AND APPEARANCE Color Change, E Note: E is an approximate value.

39

3: Acetal

Table 3-6. Tensile Strength and Elongation after Arizona Weathering Exposure for DuPont Delrin® 507 BK601 Material Family

Acetal, POM

Material Grade

DuPont Delrin® 507 BK601

Reference Number

29

Exposure Conditions Exposure Time, years

Outdoor Arizona 0

1

2

3

4

10

20

70.3

71.0

71.7

71.0

73.1

69.6

70.2

20

12

11

9

11

10

8

MECHANICAL PROPERTIES Tensile Strength, MPa Elongation, %

Table 3-7. Tensile Strength and Elongation after Michigan Weathering Exposure for DuPont Delrin® 507 BK601 Material Family

Acetal, POM

Material Grade

DuPont Delrin® 507 BK601

Reference Number

29

Exposure Conditions Exposure Time, years

Outdoor Michigan 0

1

2

3

4

10

20

70.3

70.3

70.3

70.3

72.4

69.6

64.4

20

7

13

12

14

10

11

MECHANICAL PROPERTIES Tensile Strength, MPa Elongation, %

40


Graph 3-1. Relative Tensile Strength after Accelerated Interior Weathering According to SAE J1885 for DuPont Delrin® .[30] 1

Relative Tensile Strength

UV stabilized

Standard

0.5

0

0

500

1000

Exposure (kJ/m2)

Graph 3-2. Relative Gloss after Accelerated Interior Weathering According to SAE J1885 for DuPont Delrin® .[30]

1

Relative Gloss

X27UV BK

X07 BK 0.5

X00 BK

0

0

500

Exposure (kJ/m2)

1000

41

3: Acetal Graph 3-3. Changes in Mechanical Properties after Light Exposure of Ticona Celcon® UV90Z.[27] 104.5 100.0

105.2 100.8 96.7

Izod Impact, Notched

Flex Modulus

25.0

Flex Strength

50.0

Tensile Strength

Property Retention (%)

75.0

0

Mechanical Properties Note: Total light exposure energy: 1240.8 kJ/m2 (approx. 800 hrs).

Graph 3-4. Outdoor Exposure Time vs. Impact Strength Retained of BASF Ultraform® N 2320 and Ultraform® N 2325 U Acetal Copolymer.

42


Graph 3-5. New Jersey and Arizona Outdoor Exposure Time vs. Tensile Impact Strength of Ticona Celcon® M90 and UV90 Acetal Copolymer.

Graph 3-6. New Jersey and Arizona Outdoor Exposure Time vs. Tensile Strength at Yield of Ticona Celcon® M90 Acetal Copolymer.

3: Acetal

43

Graph 3-7. New Jersey Outdoor Exposure Time vs. Tensile Strength at Yield of Ticona Celcon® GC25 A Acetal Copolymer.

Graph 3-8. QUV Exposure Time vs. E Color Change of Ticona Celcon® Acetal Copolymer.

44


Graph 3-9. Sunshine Weatherometer Exposure Time vs. Elongation Retained of Mitsubishi Iupital® F20 Acetal Copolymer.

Graph 3-10. Sunshine Weatherometer Exposure Time vs. Tensile Strength Retained of Mitsubishi Iupital® F20 Acetal Copolymer.

3: Acetal

45

Graph 3-11. Xenon Arc Weatherometer Exposure Time vs. Relative Gloss of BASF Ultraform® N Acetal Copolymer.

Chapter 4

Acrylonitrile-Styrene-Acrylate Category: Acrylic, engineering resin. General Description:Acrylonitrile-styrene-acrylate (ASA) is an acrylonitrile copolymer modified with an acrylate rubber included during the polymerization stage. •

BASF Luran® S is a styrene-acrylonitrile copolymer that has been impact modified with acrylic ester rubber.[6]

•

GE Plastics’ Geloy® ASA resin is an advanced amorphous terpolymer of acrylicstyrene-acrylonitrile.[35]

Weathering Properties Luran® S demonstrates high resistance to weathering. A special acrylic ester rubber provides resistance to UV radiation and atmospheric oxygen. The toughness, as measured by the penetration energy on 2-mm thick disks of Luran® S, is maintained after significant exposure to sunshine. The ASA + PC (polycarbonate) blends and UV-stabilized Luran® S show particularly favorable performance.[6] As a weatherable material, Geloy® resin offers exceptional durability in all kinds of harsh environments. In outdoor applications, Geloy® resins retain their color stability under long-term exposure to UV, moisture, heat, cold, and impact.[35]

Degree of Discoloration The extent of yellowing (b) of Luran® S upon exposure to sunshine remains low for up to 4000 hours. UV-stabilized Luran® S shows particularly strong performance, demonstrating virtually no yellowing after 4000 hours of exposure. The very low level of yellowing of Luran® S after exposure to outdoor weathering is comparable with that of polyvinyl chloride, a material whose suitability for outdoor applications has been proven over many years of use.[6] Luran® S in dark shades displays very little tendency towards graying when it is exposed to UV radiation or outdoor weathering and subsequently brought into contact with hot water and detergent solutions, conditions that are common in automotive applications.[6] Dark colored Luran® S formulations have only a very slight tendency toward graying after weathering followed by contact with hot water or soap solution.[6]

Thermal Resistance The resistance of Luran® S to the effect of continuous heat has been demonstrated by storage experiments at 90◦ C. A slight decrease in toughness and a strong resistance to yellowing were detected over the duration of exposure.[36]

48


Weathering Properties by Material Supplier Trade Name Table 4-1. Color Properties after Florida (45◦ South Facing) Outdoor Exposure for Pigmented GE Plastics Geloy® Material Family

ASA

Reference Number

35

Features

Country Green Siding

Pebblestone Siding

EXPOSURE CONDITIONS Exposure Type

Outdoor 45◦

Exposure Location Exposure Time (months)

0

6

12

18

South Facing Florida 24

0

6

12

18

24

SURFACE AND APPEARANCE CIELab Color Coordinates and Color Shift (D/2◦ ) L

66.2

65.6

65.6

66.1

66.3

62.5

62.3

62.2

62.6

62.4

a

−6.8

−6.7

−6.7

−6.7

−6.8

1.4

1.4

1.3

1.4

1.3

b

7.8

7.7

8.3

8.3

8.3

11

10.9

11.3

11.4

11.2

E

0

0.6

0.8

0.5

0.5

0

0.2

0.4

0.4

0.2

L

0

−0.6

−0.6

−0.1

−0.1

0

−0.2

−0.3

0.1

−0.1

a

0

0.1

0.1

0.1

0

0

0

−0.1

0

−0.1

b

0

−0.1

0.5

0.5

0.5

0

−0.1

0.3

0.4

0.2

Table 4-2. Long-Term Material Performance for GE Plastics Geloy®[25] Material Property

Performance

UV Resistance

Outstanding

Color Retention

Outstanding

Heat Resistance

Outstanding

Thermal Aging

Excellent

Note: Assumptions include processing and grade expectations that suggest long-term performance (i.e., chemical resistance, chalking, impact, weatherability, strength retention).

4: Acrylonitrile-Styrene-Acrylate

49

Table 4-3. Yellowness Index after Outdoor Weathering in Ludwigshafen, Germany, for BASF Luran® S 776 S ASA Polymer

Graph 4-1. Yellowness Index after Outdoor Exposure for BASF Luran® S 797 and Luran® S 776 ASA Polymer.

50


Graph 4-2. Color Change, E, after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer.

Graph 4-3. Impact Strength Retained after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer.


51

Graph 4-4. Elongation at Break Retained after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer.

Graph 4-5. Gloss Retained after Outdoor Weathering in Okinawa, Japan, for Mitsubishi Rayon® ASA Polymer.

52


Graph 4-6. Impact Strength Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® T110 and T120 ASA Polymer.

Graph 4-7. Impact Strength Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® ASA Polymer.


53

Graph 4-8. Elongation at Break Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® ASA Polymer.

Graph 4-9. Gloss Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® T115 and T110 ASA Polymer.

54


Graph 4-10. Gloss Retained after Sunshine Weatherometer Exposure for Mitsubishi Rayon® ASA Polymer.

Graph 4-11. Impact Strength after Weatherometer Exposure for BASF Luran® S ASA Polymer at Different Test Temperatures.

55


Graph 4-12. Impact Strength after Xenotest 1200 Exposure for BASF Luran® S 797 and Luran® S 776 ASA Polymer.

Graph 4-13. Yellowness Index of ABS, Luran® S, and Blends after Exposure to Sunshine.[6] 35

Yellowness Index

30 25

ABS or PC + ABS

20 15 10 Luran S (ASA) 5 Luran S-UV (ASA)

0 –5

0

1000

2000

3000

Hours of Exposure to Sunshine

4000

56


Graph 4-14. Penetration Energy after Exposure to Sunshine on 2-mm Thick Disks of Luran® S 778 T, Luran S® 778 T UV, Luran® S KR 2861/1 C, ABS-UV, and PC + ABS.[6]

Penetration Energy (J)

70 Luran S KR 2861/1 C

60 50

(PC + ABS) 40 Luran S 778 T UV

30 20

Luran S 778 T

ABS-UV 10 0 0

500

1000

Hours of Sunshine

1500

2000

Chapter 5

Acrylic and Acrylic Copolymer Category: Acrylic thermoplastic. General Description: Polymethyl methacrylate (PMMA) is often just called “acrylic.” PMMA is the synthetic polymer of methyl methacrylate and is amorphous, transparent, and colorless. •

Atoglas Plexiglas®

•

Cyro Acrylite®

•

Novacor NAS® 36 and Zylar® 533 are clear, UV-stabilized resins for indoor applications

•

Lucite®

Many acrylic materials are offered as “capstock” materials that are extruded over a traditional substrate material such as polyvinyl chloride. The combination provides exceptional durability and performance characteristics including UV weathering to the siding or other substrate.

Weathering Properties The weatherability of the Acrylite® GP F acrylic sheet, Acrylite® GP FL acrylic sheet, and Acrylite®

GP FL W acrylic sheet was evaluated using a Xenon Arc Accelerated Weathering System. Test samples were compared to an unexposed sample at intervals of 1000, 2000, 3000, and 5000 hours. These exposures are approximately comparable to 1, 2, 3, and 5 years of Florida outdoor exposure. Both the edge and the surface colors were evaluated. Estimates of the number of years of Florida outdoor weathering exposure required for the material to undergo significant changes in color or edge appearance are given below.[37] Plexiglas® V-series of acrylic resins provide optical clarity and resistance to UV-light degradation and discoloration. Plexiglas® V825 and V920 series resins remain virtually unchanged after longterm outdoor exposure. Plexiglas® DR resin provides outstanding transparency and UV resistance during long-term outdoor exposure.[38] NAS® 36 and Zylar® 533 have been tested for resistance to indoor light exposure according to the conditions of ASTM D4459-99. These results indicate that NAS® 36 is very well suited for indoor applications. It retains its water-white color and sparkling clarity for extended periods of time under most indoor lighting environments. NAS® 36 has better color stability than many stabilized polycarbonates. Zylar® 533 has color stability similar to stabilized polycarbonates.[38]

58


Weathering Properties by Material Supplier Trade Name Table 5-1. Cyro Acrylite® GP F Acrylic Sheet after Xenon Arc Accelerated Weathering Material Family

Acrylic, PMMA

Material Grade

Acrylite® GP F

Reference Number

37

Exposure Conditions

Xenon Arc Accelerated Weathering System

Features

Red 2149-4

Orange 3141-5

Green 564-9

Number of years of Florida outdoor weathering exposure required for the material to undergo significant changes in color or edge appearance Years

3–4

1–2

0.5

Table 5-2. Cyro Acrylite® GP FL Acrylic Sheet after Xenon Arc Accelerated Weathering Material Family

Acrylic, PMMA

Material Grade

Acrylite® GP FL

Reference Number

37

Exposure Conditions

Xenon Arc Accelerated Weathering System

Features

Red 2149-4

Orange 3105-5


5

3

Table 5-3. Cyro Acrylite® GP FLW Acrylic Sheet after Xenon Arc Accelerated Weathering Material Family

Acrylic, PMMA

Material Grade

Acrylite® GP FLW

Reference Number

37 Xenon Arc Accelerated Weathering System

Exposure Conditions Features

Red 2130-2

Dark Red 2135-1

Orange 3127-2

Yellow 4073-8

Green 5143-8

Blue 6157-9


5

1–2

3

1–2

0.5

3

59

5: Acrylic and Acrylic Copolymer

Graph 5-1. Light Transmission for Acrylic, Cyrolon® UVP Polycarbonate Sheet, and Polycarbonate after Weathering Exposure* as per ASTM D1003.[39] 94

Percentage Transmission

Acrylic

91

Cyrolon UVP Polycarbonate Sheet 88 Polycarbonate

85

0

1

2

3

5

Years Equivalent Light Transmission per ASTM D1003

*1/8 sheet (nominal) EMMAQUA Accelerated Weathered (AZ), DSET Laboratories Inc.

Graph 5-2. Yellowness Index for Acrylic, Cyrolon® UVP Polycarbonate Sheet, and Polycarbonate after Weathering Exposure* as per ASTM D1925.[39] 12 Polycarbonate

Yellowness Index

10

8

6

4

Cyrolon UVP Polycarbonate Sheet

2 Acrylic 0

1

2

3

5

Years Equivalent Yellowness Index per ASTM D1925


60


Graph 5-3. Percentage Haze for Acrylic, Cyrolon® UVP Polycarbonate Sheet, and Polycarbonate after Weathering Exposure* as per ASTM D1003.[39] 10

8

Percentage Haze

Polycarbonate

6

4

Cyrolon UVP Polycarbonate Sheet

2 Acrylic

0

1

2

3

5

Years Equivalent Haze Index per ASTM D1003


61


Graph 5-4. Luminous Transmittance, Haze, Yellowness Index, and Surface Gloss of Plexiglas® V825 after Florida and Arizona Weathering.[38] Luminous Transmittance

Haze

95.0

20.0 Florida Arizona 15.0

% Haze ASTM D1003

% Transmittance ASTM D1003

92.0 89.0 86.0

10.0

5.0

83.0

Florida Arizona 0.0

80.0 0

1

2

3

0

5

1

Years

3

5

Surface Gloss

Yellowness Index 10.0

100 Florida

9.0

95

Arizona

60° Specular Gloss ASTM D523

8.0

Yellowness Index ASTM D1925

2

Years

7.0 6.0 5.0 4.0 3.0 2.0

90 85 80 75 70 65 60

Florida

1.0

55

Arizona

0.0

50 0

1

2

Years

3

5

0

1

2

Years

3

5

62


Graph 5-5. Luminous Transmittance, Haze, Yellowness Index, and Surface Gloss of Plexiglas® DR101 after Florida and Arizona Weathering.[38] Luminous Transmittance

Haze

95.0


% Haze ASTM D1003


92.0 89.0 86.0

10.0

5.0

83.0

Florida Arizona 0.0

80.0 0

1

2

3

0

5

1

Years

3

5

Surface Gloss


100 Florida

9.0

95

Arizona


8.0


2

Years

7.0 6.0 5.0 4.0 3.0 2.0

90 85 80 75 70 65 60

Florida

1.0

55

Arizona

0.0

50 0

1

2

Years

3

5

0

1

2

Years

3

5

63


Graph 5-6. Luminous Transmittance, Haze, Yellowness Index, and Surface Gloss of Plexiglas® V920 after Florida and Arizona Weathering.[38] Luminous Transmittance

Haze

95.0


% Haze ASTM D1003


92.0 89.0 86.0

10.0

5.0

83.0

Florida Arizona 0.0

80.0 0

1

2

3

0

5

1

2

Years

5

Surface Gloss


100 Florida

9.0

95

Arizona


8.0


3

Years

7.0 6.0 5.0 4.0 3.0 2.0

90 85 80 75 70 65 60

Florida

1.0

55

Arizona

0.0

50 0

1

2

3

5

0

1

2

3

5

Years

Years

Graph 5-7. Color Change, E, after Atlas Weatherometer Exposure of Novacor NAS® 30, NAS® 36, Zylar® 533, and Other Materials.[40] ASTM D4459 (G155, Cycle #4) 5

NAS 30

Color Change (∆E)

NAS 36 4

ZYLAR 533 GP PMMA

3

UV stable PC

2

1

0 0

150

300

450

600

Xenon Arc Exposure Time (hours) Note: ASTM D4459-99 testing was performed in accordance with Method G155-00a (Table X3.2, Cycle #4) on an Atlas Ci65A Weather-Ometer® at a xenon irradiance of 0.30 W/m2 and a black panel temperature of 55◦ C.

Chapter 6

Acrylic and Polyvinyl Chloride Coextrusion Category: Coextrusion and blends. General Properties: Lucite TufCoat® is used for architectural capping (capstock). TufCoat® is literally extruded over a traditional substrate material such as polyvinyl chloride (PVC) to provide exceptional durability and performance characteristics to the siding.[41]

Weathering Properties Halogen-containing polymers (e.g., PVC) are relatively cheap and readily available materials. They have been used outdoors in buildings and glazing. However, the weatherability (e.g., the light stability)

of halogen-containing polymers is poor, leading to relatively short lifetimes particularly in pigmented formulations.[42] Acrylic materials are used in a variety of applications because of their toughness, weatherability, appearance, and stability characteristics. Thus they are often used as capstock material to provide a coating layer over a substrate thermoplastic material and provide the advantageous properties of acrylic compounds to the underlying thermoplastic material.[42] TufCoat® provides UV weathering resistance to a PVC substrate, which means that manufacturers can offer a much wider range of color options safe in the knowledge that the products will not fade or change color over time.[41]

Chapter 7

Cellulose Acetate Butyrate Category: Cellulosics. General Description: Cellulosics are synthetic plastics made from a naturally occurring polymer, cellulose, obtained from wood pulp and cotton linters. Cellulose must be chemically modified to produce a thermoplastic material. Cellulose acetate butyrate is a cellulose ester. •

Eastman Tenite® butyrate is a plastic produced from cellulose acetate butyrate. Various formulations of Tenite® butyrate have different degrees of resistance to solar radiation. The most weather-resistant butyrate formulations are typified by Tenite® butyrate 465. The most used formulas maintain material properties for five years or more when exposed continuously in Arizona and include Tenite® butyrate 465, 485, and 513.[2]

Weathering Properties Cellulose esters, like most polymeric materials, degrade when exposed to weathering. Special outdoor formulations may remain useful for at least five years outdoors in any part of the continental United States and in other areas of the world with comparable climates. Cellulose esters can be partially protected from the direct chain scission and the photo-catalyzed oxidation using UV inhibitors or UV stabilizers; protection from oxidation is obtained with antioxidants.[2] The deterioration in cellulosics caused by weathering depends on the particular cellulose ester, plasticizer, stabilizer system, wavelength of the incident radiation, total amount of radiation absorbed, temperature of the plastic, atmospheric humidity,

industrial contaminants in the atmosphere, and possibly other factors.[2] Deterioration of cellulosic plastics caused by weathering first appears as a dulling of the surface. As deterioration proceeds into advanced stages, the surface crazes and cracks; the formation of each fissure exposes the underlying plastic to the action of the weather. The onset of surface crazing does not mean the end of the usefulness of Tenite® butyrate. It will still have good tensile strength, elongation, and impact strength. Elongation is one of the best methods for determining the toughness of a plastic. A brittle material will break with little elongation and will show a smooth, glassy break. A tough material will show a ductile break with good elongation before breaking occurs.[2] Actual outdoor performance is the most reliable criterion by which the outdoor usefulness of a plastic can be judged. Eastman’s outdoor weathering program involves the exposure of many hundreds of samples at weathering stations in Kingsport, Tennessee (Lat. 36◦ 32 N, Long. 82◦ 34W, El. 1200 ft); Homestead, Florida (Lat. 26◦ 38 N, Long. 81◦ 51W, El. 9 ft); and Phoenix, Arizona (Lat. 33◦ 27 N, Long. 112◦ 3W, El. 1080 ft).[2]

Color Retention Articles made of outdoor types of Tenite® butyrate in suggested colors should give at least five years of service under even the most adverse weather conditions found in the continental United States. These most adverse conditions represent exposure to solar radiation that measures approximately 185,000 langleys per year on a horizontal surface and are found, in general, south of about 35◦ N latitude and between about 100◦ and 115◦W longitude. Comparable exposure in other parts of the world should have similar effects.[2]

68


Weathering Properties by Material Supplier Trade Name Graph 7-1. Tensile Strength at Break after Arizona Weathering for Eastman Tenite® Butyrate.[2] 6,000

5,500

35

5,000

4,500

Tensile Strength (psi)

Tensile Strength (MPa)

40

30 0

10

20

30

4,000 50

40

Exposure Time (months) Note: 3.2-mm (0.125-in.) thick specimens of an outdoor type of Tenite® butyrate.[14]

Graph 7-2. Elongation at Break after Arizona Weathering for Eastman Tenite® Butyrate.[2] 50

Elongation (%)

40

30 Black 20

Clear and Colors

10

0 0

10

20

30

Exposure Time (months) Note: 3.2-mm (0.125-in.) thick specimens of an outdoor type of Tenite® butyrate.

40

50

69

7: Cellulose Acetate Butyrate

30

40

Black

35

Clear and Colors 25

30 20 25 15

20 15

10

10 5

Impact Strength [ft·lbt at 23°C (73°F)]

Impact Strength [J at 23°C (73°F)]

Graph 7-3. Impact Strength after Weathering for Eastman Tenite® Butyrate.[2]

5 0

1

2

3

0

Time (years) Note: 3.2-mm (0.125-in.) thick specimens of an outdoor type of Tenite® butyrate; samples weathered in a vertical position facing due south. Testing as per ASTM D3029.

Chapter 8

Fluoropolymers: Overview

Due to the unique nature of the carbon–fluorine bond, most traditional fluoropolymers have the ability to withstand continuous outdoor exposure.[43] In a study of weathering resistance, three partially fluorinated polymers (ETFE, PVDF, and PVF) were exposed to UV light in a QUV Weatherometer, Q-Panel Co., at 50◦ C. The machine was equipped with UV lamps producing rays in the wavelength range of 313–550 nm. The difference between the resistance of these three fluoroplastics was characterized by the change in tensile properties as a result of exposure over time. ETFE had the most resistance in that break elongation, tensile strength, and modulus did not change upon exposure. Tensile strength and tensile modulus of PVDF remained constant while its break elongation decreased.All three properties of

Tensile Modulus (GPa)

Graph 8-1. Mechanical Properties of PVDF, ETFE, and PVF Films after South Florida Exposure.[43]


Fluoropolymer Weathering

PVF declined. Fluorine content, in addition to molecular structure, influences the UV light resistance of the fluoropolymer. Deficiencies have been overcome by incorporating organic absorbers and inorganic absorbing pigments (e.g., titanium dioxide).[43]

2.5 2.0 PVDF

1.5 1.0

ETFE

0.5

PVF

0

0

400

800 1200 1600 Irradiation Time (hrs)

2000

2400

100 80 60

ETFE PVDF

40 20

PVF

0

200

400

1000

1400

1800

2200

Irradiation Time (hrs) ETFE

400 Elongation (%)

The fluorocarbon family is made up of several branches. By varying the fluorine content of the polymer, the balance of mechanical properties can be tailored for different end use applications. As the fluorine content of a polymer increases, its resistance to chemicals and weathering, including UV resistance, also increases. Mechanical properties deteriorate with increasing fluorine content. Fully fluorinated polymers include polytetrafluoroethylene (PTFE or TFE), fluorinated ethylene propylene (FEP), and perfluoroalkoxy (PFA); partially fluorinated polymers include polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), ethylene-chlorotrifluoroethylene (ECTFE), ethylenetetrafluoroethylene (ETFE), and polyvinylfluoride (PVF).

300 200 PVDF

100

PVF

0 0

400

800

1200

1600

Irradiation Time (hrs)

2000

2400

Chapter 9

Polytetrafluoroethylene (PTFE or TFE) Category: Fluoropolymer.

Weathering Properties

General Properties: PTFE is completely unaffected by outdoor weathering. Studies have shown it to be unaffected even after twenty-five years of exposure in Florida.[44]

The outdoor weatherability of PTFE is due to its molecular structure and not as a result of additives.

•

PTFE is also known as DuPont Teflon®

Weathering Properties by Material Supplier Trade Name Table 9-1. Mechanical Properties of PTFE Film after South Florida Exposure[43] Tensile Strength (MPa)

Break Elongation (%)

Years of Exposure MD

TD

MD

TD

0

45.5

8.5

320

400

10

31.5

14.9

190

390

Property Retention (%)

69

175

59

98

Note: MD, machine direction; TD, transverse direction.

Chapter 10

Fluorinated Ethylene Propylene (FEP) Category: Fluoropolymer.


General Properties: FEP films remain essentially unchanged after twenty years of outdoor exposure with no evidence of discoloration, UV degradation, or strength loss. This outstanding performance is due to the structure of the polymer molecule and is not the result of chemical additives.[45]

Tensile strength, break elongation, and electrical properties are essentially unchanged after twenty years of outdoor exposure in South Florida.[43]

Weathering Properties by Material Supplier Trade Name Table 10-1. Mechanical Properties after 20-Year South Florida Exposure for Two Thicknesses of FEP Film[43]

Film Thickness (µm)

Years of Exposure

50


Break Elongation (%)

Tensile Modulus (MPa)

MD

TD

MD

TD

MD

TD

0

21.4

18.6

270

290

462

407

50

5

20

13.8

365

310

462

407

50

7

20

16.6

290

300

428

434

50

10

18.6

16.6

145

221

428

476

50

15

19.4

15.4

200

190

–

–

500

0

21.4

20

470

435

496

538

500

6

20

20

580

575

476

469

500

10

20.7

17.2

515

415

455

503

500

15

25.3

25.7

330

334

–

–

500

20

21.1

22.0

292

294

–

–


76


Table 10-2. Tensile Strength and Break Elongation after 20-Year South Florida Exposure for Two Thicknesses of FEP Film[43] Tensile Strength (% of initial retained)

Break Elongation (% of initial retained)

MD

TD

MD

TD

20

91

84

74

65

20

100

110

62

68

Film Thickness (µm)

Years of Exposure

50 500


Table 10-3. Material Properties (Dielectric Strength, Tensile Strength, Elongation at Break, and MIT Flex Life) of FEP Film after South Florida Exposure[43]

Length of Exposure (months)

Dielectric Strength (kV/mm)

0

Machine Direction

Transverse Direction


Elongation at Break (%)



MIT Flex Life (cycles)

124

18.0

295

15.9

300

24,000

3

112

18.8

305

16.8

265

16,300

6

132

19.0

310

16.9

300

24,400

12

132

15.9

280

15.0

305

17,400

Note: 75 µm = 0.003 in.

Table 10-4. Material Properties (Tensile Strength and Elongation at Break) of FEP Film after South Florida Exposure[43]

Length of Exposure (months)

Machine Direction

Transverse Direction





0

19.9

306

23.9

294

6

21.1

276

18.5

279

12

19.9

285

23.2

305

Note: 250 µm = 0.010 in.

77

10: Fluorinated Ethylene Propylene (FEP) Table 10-5. Electrical Properties of FEP Film after South Florida Exposure[43] Length of Exposure (months)

Dielectric Strength (kV/mm)

Dielectric Constant (1 kHz)

Dissipation Factor (1 kHz)

0

60

2.3

0.00015

6

82

2.4

0.00035

12

79

2.2

0.0002

Note: 250 µm = 0.010 in.

3000

21 All Film Thicknesses

14 0

2000 0 600

Elongation (%)

500



Graph 10-1. Retention of Tensile Strength and Percentage Elongation after Outdoor Exposure for DuPont FEP Film.[45]

50 µm/20 mils

400 300

125–250 µm/5–10 mils

200

50 µm/2 mils

100

25 µm/1 mil

0 0

2

4

6

8

10

12

14

Exposure Time (years)

16

18

Chapter 11

Perfluoroalkoxy (PFA and MFA) Category: Fluoropolymer.


General Properties: PFA is a semi-crystalline, fully fluorinated, melt-processable fluoropolymer. PFA resins are copolymers of tetrafluoroethylene with perfluorinated vinyl ethers. MFA is a copolymer of perfluoromethylvinyl ether and tetrafluoroethylene. MFA is a class of modified PFA resins that has lower performance and somewhat lower cost compared to standard PFA. Commercial PFAs are generally copolymers of perfluoropropylvinyl ether and tetrafluoroethylene.[46]

PFA is unaffected by long periods of exposure to direct sunlight, wind and rain, and exhaust gases.[47] The high clarity, low haze structure of MFA films provides excellent performance in applications requiring clear films, such as solar collectors and cell culture bags, and in UV sterilization applications.[48]

Graph 11-1. Color Change, E, after Carbon Arc Weatherometer Accelerated Weathering (Dew Cycle) for PFA and MFA.[49] 4.5 4

∆E (CIELab)

3.5 3 2.5 2 1.5 1 0.5 0 0

100

200

300

400

500

600

Exposure Time (hrs) PFA

MFA

700

800

900

1000

80


Graph 11-2. Tensile Strength Retention after Carbon Arc Weatherometer Accelerated Weathering (Dew Cycle) for PFA and MFA.[49]

Tensile Strength Retention (%)

120

100

80

60

40

20

0 0

100

200

300

400

500

600

700

800

900

1000


MFA

Graph 11-3. Elongation Retention after Carbon Arc Weatherometer Accelerated Weathering (Dew Cycle) for PFA and MFA.[49]

Elongation Retention (%)

120 100 80 60 40 20 0 0

100

200

300

400

500

600


MFA

700

800

900

1000

Chapter 12

Polyvinylidene Fluoride (PVDF) Category: Fluoropolymer. General Properties: PVDF has good weathering properties.[50] It is insensitive to UV light and does not need to be protected. Its insensitivity to UV light results in remarkable gloss retention even after natural or accelerated weathering.[51] PVDF is often used as the topcoat in capstock (a single or multilayer film that protects a plastic substrate such as polyvinyl chloride, acrylonitrilebutadiene-styrene, polycarbonate, or polyamide). Because it is completely transparent to UV wavelengths, PVDF used as topcoats contain UV absorbers to protect the substrate from damage. PVDF capstock can be formulated to last for as long as 10–30 years.[52]

Weathering Properties Transparent Arkema Kynar® Films are formulated with nonmigrating organic UV absorbers to screen natural light and protect the substrate from UV damage.[51] 1. Be 99% opaque (absorbance > 2) up to 400 nm for 2000 hours in the SEPAP 12-24∗ accelerated weathering test. 2. Ensure a gloss retention > 80% and a color shift E < 2 after 1000 hours in weatherometer accelerated testing∗∗ (a typical requirement in automotive applications).

The absorbance at 320 nm can be plotted as a function of time to visualize the performance of the film. It can be seen that a 50-µm thick film maintains 99% UV opacity (absorbance > 2) for more than 2000 hours and is still 90% UV opaque (absorbance > 1) after 4000 hours of accelerated weathering in the SEPAP 12-24 test.[51] The mechanical properties of Kynar® film are maintained throughout many years of outdoor exposure. Clear films exposed to the sun at a 45◦ angle south retained their tensile strengths over a 17-year period. During the first few months of exposure when normal crystallization takes places, the percentage of elongation at break decreases to a level that remains essentially constant with time. In addition, the weathered films remain flexible and are capable of being bent up to 180◦ without cracking.[53] Arkema Kynar® 500 is a special grade of PVDF resin used by licensed industrial paint manufacturers as the base resin in long-life coatings called coil coatings.[54] Solvay Solexis Halar® 5000 LG and HG are specifically designed for solvent-based coatings to provide improved gloss. The weathering characteristics of Hylar® 5000 coatings lead to excellent performance for the long term.[42] Solvay Solexis Halar® 5000 PVDF films are highly resistant to most environmental conditions including gamma radiation and are essentially transparent to UV radiation.[52] Solvay Solexis Solef ® 11010 and Solef ® 21508 are PVDF copolymers.

∗ SEPAP

12-24: Climate chamber equipped with four artificial lamps (mercury vapor: unit power 400 W) with cutoff of UV radiation below 300 nm; samples are continuously exposed without water sprinkling; temperature is maintained at 60◦ C. Note that the SEPAP 12-24 test is extremely demanding since the UV exposure is permanent (no night and day cycle). ∗∗ WOM CI135A: Climate chamber equipped with three artificial lamps (xenon arc: 63 W/m2 between 300 and 400 nm) with

cutoff of UV radiation below 290 nm; samples are exposed alternatively to the lamps and sprinkled with water for 18 min every 102 min; relative humidity is maintained at 50% and temperature at 70◦ C (dry period).

82


Table 12-1. Mechanical Properties and Yellowness Index after Arizona Outdoor Weathering Exposure for Solvey Solexis Solef® 11010 Material Family

Polyvinylidene fluoride (PVDF)

Material Grade

Solvay Solexis Solef® 11010

Reference Number

49

Exposure Conditions

Outdoor Arizona

Sample Thickness (µm)

75


0

0.5

1

6

9

Tensile Impact (kJ/m2 )

3410

2796

2318

2707

–

Tensile Strength at Yield (MPa)

21.5

23.3

24.7

24.1

25

Elongation at Yield (%)

21

–

–

9.5

10.1

Tensile Strength at Break (MPa)

54

43.7

48.6

55.7

54.3


470

374

380

410

416

Elmendorf Tear Strength (N)

2.5

1.5

1.5

3.5

3.1

1.9

4.1

3.4

1.2

4.7

MECHANICAL PROPERTIES

SURFACE AND APPEARANCE Yellowness Index

Table 12-2. Yellowness Index after QUV Accelerated Weathering Exposure (UV-B 313) for Solvey Solexis Solef ® 21508 Material Family

Polyvinylidene fluoride (PVDF)

Material Grade

Solvay Solexis Solef® 21508

Reference Number

49

Exposure Conditions

UV-B 313, ASTM D1925

Exposure Time (hrs)

0

200

600

1200

2000

4000

Yellowness Index

–0.9

–0.5

–0.5

–0.4

–0.4

–0.3

L*

93.4

93.0

92.9

93.1

93.1

93.0

a*

–1.0

–0.9

–0.9

–0.9

–0.9

–0.9

–0.1

0.1

0.1

0.1

0.1

0.2

116

106

93

101

98

76

SURFACE AND APPEARANCE

b* Gloss at

60◦

*CIE 1976 measured by

Hunterlab—D65/10◦ .

12: Polyvinylidene Fluoride (PVDF)

83

Table 12-3. Retention of Mechanical Properties after Outdoor Weathering of Arkema Kynar® PVDF Film

Table 12-4. Retention of Mechanical Properties after Xenon Arc Weatherometer Exposure of PVDF

84


Graph 12-1. Retention of Tensile Strength and Elongation after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for PVDF Film.[49] 120

Retention (%)

100

80

60

40

20

0 0

1

2

3

4

5

Exposure Time (years) Retention of Tensile Strength

Retention of Elongation

Graph 12-2. Color Change, E, after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for Solvay Solexis Hylar® 5000 PVDF Pigmented Coatings.[49] 5 4.5 4

∆E (CIELab)

3.5 3 2.5 2 1.5 1 0.5 0 0

1

2

3

4

5

6

7

8

Aging Time (years) Blue

Brown

Yellow

Green

Black

9

10

85

12: Polyvinylidene Fluoride (PVDF)

Graph 12-3. Gloss Retention after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for Solvay Solexis Hylar® 5000 PVDF Pigmented Coatings.[49] 120

Gloss Retention (%)

100

80

60

40

20

0 0

1

2

3

4

5

6

7

8

9

10

Aging Time (years) Blue

Brown

Yellow

Green

Black

Graph 12-4. Chalk Rating after Florida Exposure (45◦ Angle South) for Commercial White Paints.[56] 10 PVDF 9

Silicone Polyester

8 Acrylic

Chalk Rating

7 6

Plastisol

5 4 3

Urethane

2 1 0

0

2

4

6


8

10

86


Graph 12-5. Gloss Retention after Florida Exposure (45◦ Angle South) for Commercial White Paints.[56] 120 PVDF

Gloss Retention (%)

100

80

Silicone Polyester

60

40

Acrylic

20

Vinyl Plastisol Urethane

0 0

2

4 6 Exposure Time (years)

8

10

Chapter 13

Polychlorotrifluoroethylene (PCTFE) Category: Fluoropolymer. General Properties: Honeywell Aclar® PCTFE films are extremely resistant to UV radiation, as tested in a weatherometer with water spray.[57]

Graph 13-1. Elongation Retained in the Machine Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE.

88


Graph 13-2. Elongation Retained in the Transverse Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE.

Graph 13-3. Tensile Strength Retained in the Machine Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE.

13: Polychlorotriﬂuoroethylene (PCTFE)

89

Graph 13-4. Tensile Strength Retained in the Transverse Direction after Weatherometer Exposure of Honeywell Aclar® 22A and Aclar® 33C PCTFE.

Chapter 14

Ethylene-chlorotrifluoroethylene (ECTFE) Category: Fluoropolymer.


General Properties: ECTFE undergoes very little change in properties or appearance on outdoor exposure to sunlight.

Solvay Solexis Halar® ECTFE shows no change after 1000 hours in a weatherometer.[58]

Table 14-1. Accelerated Weathering of Solvay Solexis Halar® ECTFE in a Xenon Arc Weatherometer

92


Graph 14-1. Retention of Tensile Strength and Elongation after Miami, Florida, Outdoor Weathering Exposure (45◦ Angle South) for Solvay Solexis Halar® ECTFE Film.[49]

100

Retention (%)

80

60

40

20

0 0

1

2

3

4

5

6

7

8

9

Exposure Time (years) % Retention of Tensile Strength

% Retention of Elongation

Graph 14-2. Retention of Tensile Strength and Elongation after QUV Accelerated Weathering Exposure, UVB-313, for Solvay Solexis Halar® ECTFE Film.[49]

100

Retention (%)

80

60

40

20

0 0

500

1000

1500

2000

2500

3000

3500

4000

Exposure Time (hrs) Retention of Tensile Strength

Retention of Elongation

4500

5000

93

14: Ethylene-chlorotrifluoroethylene (ECTFE)

Graph 14-3. Color Change, E, after QUV Accelerated Weathering Exposure, UVB-313, for Solvay Solexis Halar® ECTFE Film.[49] 5

∆E (CIELab)

4

3

2

1

0 0

500

1000

1500

2000

2500

3000

Exposure Time (hrs) Halar ECTFE Film

3500

4000

4500

5000

Chapter 15

Ethylene-tetrafluoroethylene (ETFE) Category: Fluoropolymer.


General Properties: ETFE has high weathering resistance, showing no deterioration or change in properties as a result of exposure to direct sunlight, wind and rain, and exhaust gases.[58]

Exposure of DuPont Tefzel® 200 for more than one year in Florida and Michigan has had no effect.[59] DuPont Tefzel® films have excellent outdoor weathering performance.[60]

Table 15-1. Accelerated Weathering of DuPont Tefzel® 200 ETFE in a Weatherometer

Chapter 16

Polyvinyl Fluoride (PVF) General Description •

DuPont Tedlar® PVF film

•

DuPont Tedlar® SP PVF

Weathering Properties PVF has outstanding weathering properties.[50] Pigmented Tedlar® , when properly laminated to a variety of substrates, imparts a long service life.[61] DuPont Tedlar® PVF film has excellent resistance to sunlight degradation, stands up well to atmospheric pollutants, and is resistant to acid rain attack and mildew. Most airborne dirt does not adhere to Tedlar® film.[61] Tedlar® is available as a pigmented or nearcolorless, transparent film. The pigmented films offer the highest level of protection from UV light degradation, as the pigments block nearly all UV and visible light from passing through the film. This means that the materials underneath the film will not be exposed to high-energy, destructive light.[61]

The transparent films are available in an enhanced UV-screening formula that blocks nearly all of the UV light up to 350 nm. These UV-absorbing films screen out progressively less UV light at the less harmful, lower energy end of the UV spectrum (350–400 nm) and block very little visible light.[30] Unsupported transparent Tedlar retains at least 50% of its tensile strength after ten years of exposure in Florida at an angle of 45◦ facing south.[61] Most colors exhibit no more than five NBS units (modified Adams color coordinates) of color change after twenty years of vertical, US outdoor exposure.[61] Tedlar® SP films match or exceed the resistance of high-quality plastic surfacing materials to color fade and loss of gloss. Color retention of Tedlar® SP films is dependent upon the color being tested.[62] High-gloss Tedlar® SP films have been found to perform similarly to original equipment manufacturer basecoat/clearcoat paints for gloss retention under xenon arc weathering, and provide superior gloss retention compared to other high-gloss films, refinish paints, and coextrusions.[62]

98


Graph 16-1. Percentage of Initial Properties Retained after South Florida Weathering Exposure at an Angle of 45◦ Facing South for DuPont Tedlar® PVF Film.[63] 100

Tensile

% of Initial Properties Retained

80

Elongation 60

40

20

0

1

2

3

4

5

6


Graph 16-2. Percentage Gloss Retention after South Florida Weathering Exposure at an Angle of 45◦ Facing South for DuPont Tedlar® PVF Film and Pigmented Vinyl Film.[61]

100

60° Gloss Retention (%)

80

60

40 TUT10BG3 Tedlar ® Film Pigmented Vinyl 20

0 0

1

2

3


4

5

99

16: Polyvinyl Fluoride (PVF)

Graph 16-3. Average Rate of UV Absorber Degradation in Free-Standing DuPont Tedlar® PVF Film after Florida Exposure.[61] 100

Initial Absorbance at 360 nm (%)

80

60

40

20

0

0

2

4

6

8

10

Florida Exposure (years; 45° Angle, Facing South)

Graph 16-4. Color Stability of DuPont Tedlar® PVF Film after Exposure to Atlas Sunshine Arc Weatherometer.[63] 5

Color Stability

4

3

2

1

0 1000

2000

3000

Exposure Time (hrs) Note: Colored films vary slightly in color retention, depending on color.

4000

5000

100


Graph 16-5. Percentage of Initial Properties Retained after Atlas Sunshine Arc Weatherometer Exposure of DuPont Tedlar® PVF Film.[63] 100

Tensile % of Initial Properties Retained

80

60

Elongation

40

20

0

2000

4000

6000

8000

Exposure Time (hrs)

Graph 16-6. Typical Color Change Range of a Variety of Pigmented DuPont Tedlar® SP Films after Xenon Arc Exposure as per the SAE J1960 Method.[62] 5

∆E (CIE94)

4

3

2

1

0 0

1200

2400

3600

Exposure (kJ)

4800

6000

7200

101

16: Polyvinyl Fluoride (PVF)

Graph 16-7. Gloss Retention of Refinish Paint, Gel Coat, and DuPont Tedlar® SP Film after Xenon Arc Exposure as per the SAE J1960 Method.[62] 100

60° Gloss

80

60

40

Tedlar ® SP Film Gel Coat

20

Refinish Paint 0 0

600

1200

1800

2400

Exposure (kJ)

Graph 16-8. Gloss Retention of Acrylic Film, ASA/AES Copolymer, and DuPont Tedlar® SP Film after Xenon Arc Exposure as per the SAE J1960 Method.[62] 100

60° Gloss

80

60

40

Tedlar ® SP Film Acrylic Film

20

ASA/AES Copolymer 0 0

600

1200

Exposure (kJ)

1800

2400

Chapter 17

Ionomer Category: Thermoplastic elastomer (TPE). General Properties: Ionomers are thermoplastic copolymers that can be processed like thermoplastics and demonstrate mechanical properties like elastomers or cross-linked polymers.[64]

Weathering Properties Ionomers have poor weathering resistance and must be stabilized if they are exposed to sunlight or outdoor weather. Outdoor weathering experience has confirmed the outstanding performance of UV-stabilized DuPont Surlyn® . Parts containing carbon black have been in service and exposed to all types of weather for over ten years with no significant change in physical integrity or appearance. Other pigmented parts have retained their physical integrity and appearance after five years of exposure to an Arizona environment.[65] Production samples of automotive exterior trim extrusions coated with clear, UV-stabilized Surlyn® and clear, UV-stabilized polyvinyl chloride were exposed side by side in up to 5000 hours of accelerated weathering tests. Besides the obvious edge in UV stability, Surlyn® ionomer resin requires no liquid plasticizer, and therefore there will be no migration problems in the finished part.[66] The most traditional and positive method of stabilizing ionomers for long-term usage in allweather environments requires the addition of 0.2% antioxidant and 5% (by weight) of well-dispersed, micrometer-sized carbon black. With this modification, products made from DuPont Surlyn® have been in continuous service for over ten years.[65] The development of technology for stabilizing clear or color-pigmented ionomers is a dynamic process. Earlier recommendations, based on the incorporation of antioxidant and UV absorbers, have produced pigmented products that still retain their

physical integrity and appearance after five years of normal exposure to an Arizona environment.[65] Subsequent development of newer stabilizers and “energy quencher” additives has led to broader recommendations for both clear and pigmented systems. There is no complete, comprehensive system for UV protection. However, based on continued research with accelerated testing and evaluation of long-term Florida exposure, it is possible to present a series of basic rules that provide an opportunity to customize the use of polymer modifiers.[65] The six basic rules for UV protection in ionomers are:[65] 1. Use zinc type ionomers for a more stable base and long-term performance. 2. It is essential to use antioxidants with all stabilizer systems. 3. Both sodium and zinc type ionomers may be modified for protection from occasional exposure to sunlight (less than 200 hours/year). 4. For maximum retention of tensile and impact properties, a combination of an antioxidant (UV absorber) and an energy quencher must be used. In pigmented parts, this should not present any limitations in product appearance. However, in clear, transparent applications, the presence of currently recommended UV absorbers may create unacceptable levels of yellowness, depending upon the part thickness. 5. When maximum retention of clarity, surface brilliance, and absence of color formation are primary end-use considerations, a combination of an antioxidant and an energy quencher is recommended. In this system, tensile and impact characteristics will decline

104


to one-third the level of natural grade properties. 6. In either of the above cases (4 and 5), addition of 2–10 ppm of Monastral blue or violet (transparent pigment) will neutralize the observation of slightly yellow tints.

In applications where retention of “water white” clarity is necessary, elimination of the UV absorber component will reduce the yellow coloration. However, tensile properties will degrade to approximately 30% of the original. The use of a masking agent neutralizes the slight color due to the energy quencher.[65]

Table 17-1. Physical Properties and Visual Appearance after Florida and Arizona Outdoor Weathering for UV-Stabilized DuPont Surlyn® Ionomer

17: Ionomer

105

Table 17-2. Physical Properties and Visual Appearance after Accelerated Weathering in an Atlas Weatherometer for Zinc Ion Type UV-Stabilized DuPont Surlyn® Ionomer

106


Table 17-3. Physical Properties and Visual Appearance after Accelerated Weathering in an Atlas Weatherometer for Zinc Ion Type UV- and Antioxidant-Stabilized, Pigmented DuPont Surlyn® Ionomer

17: Ionomer

107

Table 17-4. Physical Properties and Visual Appearance after Accelerated Weathering in an Atlas Weatherometer for Sodium IonType UV- and Antioxidant-Stabilized, Pigmented DuPont Surlyn® Ionomer

108


Table 17-5. Physical Properties and Visual Appearance after Accelerated Weathering in a QUV Weatherometer for Zinc Ion Type DuPont Surlyn® Ionomer

Chapter 18

Polyphenylene Oxide Category: Polyphenylene ether (PPE)/polyphenylene oxide (PPO), polystyrene, thermoplastic. General Properties: GE Plastics Noryl® engineering thermoplastic resin is based on PPE (made and sold by GE Plastics under the trademark PPO). PPE, a high-heat amorphous polymer, forms a miscible, single-phase blend with polystyrene. This technology, in combination with other additives, provides a family of resins covering a wide range of physical and thermomechanical properties.[67]

Weathering Resistance PPO blends have good weathering resistance when adequately stabilized, but uncolored grades will yellow in UV light. Black grades have the best UV resistance.[68] Noryl® resins should not degrade, decompose, chalk, craze, or crack on exposure to outdoor weathering.[69] Noryl® resins will:[69] 1. Lose some impact and elongation (20–40%) strength depending on grade.

2. Gain tensile and flexural strength (5–15%) on long-term exposure. 3. Lose any surface gloss within a few months and become dull. 4. Change to a shade of color which is more yellow or darker on exposure. Only surface discoloration will occur. However, very thin sections (under 12.7 mm) may become more brittle. This brittleness occurs because the surface layers which are losing impact strength and becoming stiffer make up a proportionately larger volume of a thin section than a thicker section.[70] When exposed to outdoor light, parts of Noryl® resin undergo a color change with a tendency to darken slightly and drift toward yellow. When selecting Noryl® resins for outdoor use, dark colors— black and brown—are recommended, as well as reds, yellows, and oranges, which show excellent color stability and where the tendency to yellow is masked.[70]

110


Table 18-1. Change in Yellowness Index and Percentage Gloss Retained after Outdoor Weathering Exposure in Arizona, Florida, and New York for GE Plastics Noryl® Modified PPO

Graph 18-1. Change in Color, E, after Accelerated Indoor UV Exposure of Modified PPO.

18: Polyphenylene Oxide

Graph 18-2. Dart Drop Impact Strength after Arizona Outdoor Weathering Exposure of Modified PPO.

Graph 18-3. Percentage Elongation after Arizona Outdoor Weathering Exposure of Modified PPO.

111

112


Graph 18-4. Tensile Strength after Arizona Outdoor Weathering Exposure of Modified PPO.

Graph 18-5. Change in Color, E, after Arizona Outdoor Weathering Exposure of Modified PPO.

18: Polyphenylene Oxide

Graph 18-6. Change in Color, E, after Ohio Outdoor Weathering Exposure of Modified PPO.

Graph 18-7. Dart Drop Impact Strength after Ohio Outdoor Weathering Exposure of Modified PPO.

113

Chapter 19

Nylon: Overview Category: Engineering resins, polyamide (PA). General Properties: Nylon is the common name for high-molecular weight PAs—semi-crystalline polymers typically produced by the condensation of a diacid and a diamine. There are several types of nylon; the numeric suffixes refer to the number of carbon atoms present in the molecular structures of the amine and acid, respectively, or a single suffix if the amine and acid groups are part of the same molecule. Nylons also differ structurally in the way the polymer chains are able to align and bond together. Amorphous grades of nylon are also available. The most widely used types are nylon 6 (PA6) and nylon 6,6 (PA6,6).

Weathering Properties: General Nylons are sensitive to UV radiation. Nylons find applications as engineering plastics as well as fiber materials. During normal use they are often exposed to sunlight, which causes extensive degradation of the polymer. Weatherability will be reduced unless UV stabilizers are incorporated into the formulation. Carbon black is the most commonly used UV stabilizer. Carbon black lowers the ductility and toughness as a trade-off for UV stability.[71]

Weathering Properties: UV Stabilization Honeywell offers a UV-stabilized nylon with a synergistic combination of additives—a reactive siloxane, a hindered amine, and a phosphite. This package offers a significant improvement in the UV stabilization of nylon resins. Nylon materials produced with this stabilizer system maintain their appearance upon weathering and are highly useful for a wide variety of structural and decorative articles.[72]

Weathering Properties: Colored Material Dyes are commonly used to add color to nylon. A key component of dye lightfastness is the type of dye chosen. Acidic and basic dyes react with the nylon molecule while disperse dyes are physically entrapped.

Chapter 20

Nylon 6 Category: Polyamide 6 (PA6). General Properties: BASF Ultramid® nylon 6 resins are high strength and stiffness molding compounds.

Weathering Properties Many Ultramid® resins are suitable for outdoor applications. The unreinforced stabilized Ultramid® resins (i.e., those with the letters K and H in the nomenclature type) are extremely resistant to weathering, even if they are uncolored. The outdoor performance can be further improved by the use of suitable pigments, the best effects being achieved with carbon black. For instance, seats that have been produced from Ultramid® B3K and B35K containing

special UV stabilizers and have been exposed for more than ten years in an open-air stadium have remained unbreakable, and their appearance has undergone hardly any change.[73] Thin articles for outdoor use should be produced from Ultramid® resins with a high carbon black content (e.g., the Black 20590 and 20592 types) to ensure that their strength remains undiminished. Moldings with a high proportion of carbon black can also withstand several years of exposure to tropical conditions.[73] Housings for automobile rear-view mirrors are examples of articles that must remain attractive for many years. In this type of application, the best results have been obtained with products containing special UV stabilizers and products with a high carbon black content (e.g., Ultramid® B35EG3 Black 20590).[73]

118


Table 20-1. Mechanical Properties Retained after Outdoor Weathering Exposure in Florida for BASF Capron® Nylon 6

20: Nylon 6

119

Table 20-2. Mechanical Properties Retained after Outdoor Weathering Exposure in California and Pennsylvania for LNP Engineering Plastics® Nylon 6

Graph 20-1. Elongation at Break after Outdoor Exposure for Ube Ube® Nylon 6.

120


Graph 20-2. Flexural Modulus after Outdoor Exposure for Ube Ube® Nylon 6.

Graph 20-3. Notched Izod Impact Strength after Outdoor Exposure for Ube Ube® Nylon 6.

20: Nylon 6 Graph 20-4. Tensile Strength after Outdoor Exposure for Ube Ube® Nylon 6.

Graph 20-5. Flexural Strength at Break after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6.

121

122


Graph 20-6. Flexural Modulus after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6.

Graph 20-7. Notched Izod Impact Strength after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6.

20: Nylon 6 Graph 20-8. Weight Change after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6.

Graph 20-9. Flexural Strength after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6.

123

124


Graph 20-10. Tensile Strength after Outdoor Exposure in Hiratsuka, Japan, for Nylon 6.

Graph 20-11. Elongation after Sunshine Weatherometer Exposure of Nylon 6.

20: Nylon 6

Graph 20-12. Tensile Strength after Sunshine Weatherometer Exposure of Nylon 6.

125

Chapter 21

Nylon 12 Category: Polyamide 12 (PA12), thermoplastic. General Properties: EMS Grivory Grilamid® TR grades are transparent, thermoplastic polyamides based on aliphatic, cycloaliphatic, and aromatic blocks. Due to their composition, Grilamid TR grades combine the excellent properties of semicrystalline polyamide twelve types with those of an amorphous thermoplastic in a unique way.[79] •

Grilamid® TR 55

•

Grilamid® TR 55 LX

•

Grilamid® TR 55 LY is characterized by its good chemical and stress-crack resistance.

•

Grilamid® TR 90 is characterized by its extremely good UV resistance, high chemical and stress-crack resistance as well as high impact strength.

•

Grilamid® TR 90 UV is a water-clear transparent polyamide with outstanding weathering stability and excellent chemical resistance.

Weathering Properties Grilamid® TR 55 and TR 55 UV test plaques have been exposed for 40 months in southeast

Switzerland at 45◦ , facing south. Unstabilized Grilamid® TR 55 retained good transparency, but displayed some discoloration after 4 months of exposure and some brittleness after 25 months.[80] In contrast, Grilamid® TR 55 UV maintained its transparency with no brittleness, surface crazing or degradation, and no effect on relative viscosity. A small increase in yellowness occurred for up to eleven months of exposure and then showed no further increase. This compares very favorably with a typical stabilized polycarbonate in the same test, which showed significant loss of molecular weight and an increase in yellowness that seriously impaired transparency.[80] Samples of Grilamid® TR 55 and TR 55 UV were tested in an Atlas weatherometer, in cycles of 20 minutes (17 minutes of UV exposure followed by 3 minutes of UV exposure plus water spray). After 2000 hours, Grilamid® TR 55 UV showed no measurable change in color or surface appearance. In contrast, the unstabilized Grilamid® TR 55, while retaining transparency, showed an increase in yellowness and a slightly matte surface—a behavior similar to unstabilized polycarbonate.[80]

128


Graph 21-1. Change in Color, E, after Weatherometer Exposure of EMS Grilamid® TR 55, TR 55 LX, TR 90, and TR 90 UV Nylon 12 Compared to Other Polymers.[81] 20 PA 3-6-T TR 55 LX

∆E/1 mm

15

TR 55 PC UV

10

TR 90 TR 90 UV PA PACM12

5

PMMA 0 0

500

1000

1500

2000

2500

3000

Exposure Time (hrs)

Graph 21-2. Yellow Index (YI) after Weathering Exposure as per ASTM D1975 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX.[82] 25 TR 90 TR 90 UV

YI ASTM D1975

20

TR 55 LX TR 55

15 10 5 0 0

1000

2000

3000

4000

Exposure Time (hrs)

5000

6000

129

21: Nylon 12

Graph 21-3. Tensile Impact Strength after Weatherometer Exposure for EMS Grilamid® TR 55, TR 55 LX, and TR 55 LY Nylon 12.

Graph 21-4. Tensile Impact Strength after Weatherometer Exposure for EMS Grilamid® TR 90 and TR 90 UV Compared to Other Polymers.[81] 1000 TR 90 UV

2

Tensile Impact Strength (kJ/m )

TR 90 800 PA PACM12 PC UV 600

400

200

0 0

500

1000

1500

2000

Exposure Time (hrs)

2500

3000

130


Half-Life Time (hrs)

Graph 21-5. Tensile Impact Strength Half-Life after Weathering for EMS Grilamid® TR 90, TR 90 LX, and TR 90 UV Compared to Other Polymers.[81] >2000

2000 1800 1600 1400 1200 1000 800 600 400 200 0 T

6-

PA

3-

TR

45

PC

G

V

PC

U

TR

90 TR

90

LX

V

12

M

PA

C PA

>2000

TR

90

U

A

M

PM

Graph 21-6. Yield Strength after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX.[82] 100 TR 90

90

TR 90 UV

Yield Strength (MPa)

80

TR 55 LX 70 TR 55 60 50 40 30 20 10 0 0

1000

2000

3000

4000

5000

6000

7000

8000

Exposure Time (hrs)

Graph 21-7. Percentage Retention of Yield Strength after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX.[82] 120

TR 90 TR 90 UV

100

Yield Strength (%)

TR 55 LX TR 55

80 60 40 20 0 0

1000

2000

3000

4000

5000

Exposure Time (hrs)

6000

7000

8000

131

21: Nylon 12

Graph 21-8. Percentage Retention of Elongation at Break after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, TR 55, and TR 55 LX.[82] 140 TR 90 TR 90 UV


120

TR 55 LX 100

TR 55

80 60 40 20 0 0

1000

2000

3000

4000

5000

6000

7000

8000

Exposure Time (hrs)

Graph 21-9. Percentage Retention of Work to Break after Weathering Exposure as per ISO 4892-2 for EMS Grilamid® TR 90, TR 90 UV, and TR 55 LX.[82]

Work to Break (%)

180

TR 90

160

TR 90 UV

140

TR 55 LX

120 100 80 60 40 20 0 0

1000

2000

3000

4000

5000

Exposure Time (hrs)

6000

7000

8000

132


Graph 21-10. Transparency of EMS Grilamid® and EMS Grivory® Compared to Glass and Other Polymers.[81] 100 90

90

91

89

Transparency (%) 540 nm, 3 mm

90

90

89

87

85

80 70 60

G la ss

PS

A

G riv or

y

PM

M

PC

45 G TR

LX 70 TR id

id G ril am

G ril am

G ril am

id

TR

TR

55

90

50

Graph 21-11. Transparency in the Visible Spectrum of EMS Grilamid® Compared to Other Polymers.[81] 100

Transmission (%)

80

60

40

20

0 200

250

300

350

400

450

500

550

600

650

700

Wavelength (nm) TR 55

TR 90

Note: Spectrometer LAMBDA 19 UV/VIS/NIR, thickness 2 mm.

PMMA

PC

750

800

Chapter 22

Nylon with Glass Fiber Category: Polyamide with glass fiber reinforcement.

General Properties: Glass fibers can be added to increase the stiffness of nylon. Because material properties such as elongation and impact strength can be adversely impacted by the addition of glass fibers, a toughener is often included in the product formulation to retain initial elongation and impact strength. Fiberglass reinforcement improves the strength, stiffness, dimensional stability, and performance at elevated temperatures of BASF’s Ultramid® nylon. Reinforcement levels of the different grades range from 6% to 63%.

Weathering Properties The reinforced Ultramid® resins also give good outdoor performance, and the stabilized types (e.g., Ultramid® B3EG5) can be relied upon to withstand exposure for periods greater than 5 years. Nevertheless, the constituent glass fibers cause the surface to be attacked more severely than that of unreinforced Ultramid® articles.As a consequence, the texture and the hue may undergo a change after comparatively brief exposure periods. If the glass-reinforced moldings remain exposed for a number of years, erosion to a depth of a few tenths of a millimeter (0.04 in.) can generally be expected, but experience has shown that this does not exert any significant effect on the mechanical properties.[73]

Table 22-1. Material Properties Retained after Outdoor Weathering in California and Pennsylvania for LNP (a Division of GE Plastics) Glass-Reinforced Nylon 610

Chapter 23

Nylon 66 Category: Polyamide 66 (PA66) thermoplastic. General Properties: DuPont Zytel® nylon 66 polymer family is available in glass, mineral, super tough, or unreinforced grades. Zytel® 101 is a general purpose unreinforced PA66.

Weathering Properties Nylon 66 degrades upon exposure to natural and artificial weathering. This degradation causes changes in its chemical, physical, and mechanical properties. The degree of changes depends on the wavelength of the UV radiation and the atmospheric conditions. Chromophores∗ , defects, and impurities initiate the hydroperoxidation∗∗ when nylon polymers are exposed to light of higher wavelength (λ = 340 nm), whereas at lower wavelength (λ = 254 nm) exposure, direct photoscission occurs, which is independent of the length of the carbon chain.[84] Neat (not dyed, not bonded, not stabilized) nylon 66 tops the chart for strength retention after nine months of exposure in Florida. When natural colored fibers were tested for nine months of exposure

∗ Chromophore

is the light absorbing part of a photopigment. Many natural pigments are based on the quinone chromophore. The ability of a compound to absorb light depends on the presence of certain kinds of structural features (i.e., chromophores). ∗∗ Hydroperoxidation is the decay of the hydroperoxide radical (R–C–O–O• ).

in Florida sunlight, the DuPont type 66-728 nylon showed the highest percentage of strength retention when compared to nylon 6, polyester, and polypropylene. The resistance to UV exposure and weathering increases substantially as UV stabilizers, dyestuffs, and bonding agents are added in the manufacturing process. Starting with the right raw material is crucial in obtaining long life and durability.[85]

Weathering Properties: Colored Material Nylon 66 is relatively resistant to fading due to sunlight or atmospheric conditions. Nylon 66 is often dyed to provide color. A key component of dye lightfastness is the type of dye chosen. The dye diffusion rate for nylon 66 is relatively slow. However, it is difficult to remove dye from the finished product. Nylon 66 is therefore a relatively lightfast nylon. Nylon 66 is also resilient to the diffusion of other molecules through the fiber, like ozone and nitrous oxide, which can harm the fiber or dye.[85]

Chapter 24

Nylon 6,6T Category: Polyamide 6,6, thermoplastic, partly aromatic polyamide. General Properties: BASF Ultramid® 6/6T is a semi-crystalline, semi-aromatic nylon 6/6T or 6,6T.

Weathering Properties The experience gained in the outdoor performance of Ultramid® A and B applies essentially to

Ultramid® T. However, Ultramid® T is degraded and discolored somewhat more rapidly than nylon 66 and nylon 6 when exposed to prolonged UV radiation.[86]

Chapter 25

Nylon MXD6 Category: Aliphatic polyamide. General Properties: Nylon MXD6 is a crystalline polyamide resin developed by Mitsubishi Gas Chemical Company, Inc, which is produced through the polycondensation of meta-xylene diamine (MXDA) with adipic acid.

Graph 25-1. Flexural Modulus after Outdoor Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon.

140


Graph 25-2. Notched Izod Impact Strength after Outdoor Weathering Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon.

Graph 25-3. Flexural Strength after Outdoor Weathering Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon.

25: Nylon MXD6

141

Graph 25-4. Tensile Strength after Outdoor Weathering Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon.

Graph 25-5. Elongation (%) after Sunshine Weatherometer Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon.

142


Graph 25-6. Tensile Strength after Sunshine Weatherometer Exposure in Hiratsuka, Japan, for Mitsubishi Reny® MXD6 Nylon.

Chapter 26

Polyarylamide Category: Filled/reinforced thermoplastic, polyarylamide. General Properties: Solvay Advanced Polymers IXEF® compounds are a family of semi-crystalline polyarylamide thermoplastics reinforced with glass fibers. IXEF® 1002 contains 30% glass fiber, while IXEF® 1022 contains 50% glass fiber.

Weathering Properties Specimens of IXEF® 1002 and IXEF® 1011 were exposed to the weather for four years at the Hiratsuka Test Station under the following conditions: average temperature 23◦ C, extremes 0◦ C and 30◦ C; average precipitation = 130 mm per month, extremes 50–200 mm per month; total solar irradiance 500 kJ/cm2 per year.[77] The results obtained on the 3.2 mm specimens showed: 1. Water absorption of approximately 0.8%. 2. An approximate 30% reduction in the maximum stress, essentially corresponding to the reversible plasticization brought about by water. 3. No change in flexural modulus.

The surface of a part made from IXEF® product is a layer of pure polymer approximately 1 µm thick. This layer allows a very good gloss finish to be obtained. If photo-oxidation occurs, this layer deteriorates as a result of a change in the roughness of the surface (e.g., an increase from Ra = 0.15 µm to Ra = 2 µm). If a very small quantity of material (3 mg/m2 ) undergoes oxidation, it results in a change in the appearance of the surface (gloss and color) without the other properties of the material being affected in any way.[77] When choosing the surface appearance of parts likely to be exposed to UV, it is advisable to avoid excessively low roughness levels because they will be affected to a considerable degree by superficial photo-oxidation.[77] To date, experience with outdoor IXEF applications has established that the variations in shades observed are acceptable for many colors. Some particularly exacting sectors of the market have very stringent requirements; special IXEF grades may satisfy these requirements in certain cases.[77] Flame-resistant grades exhibit variations in shade that are generally unacceptable for light colors.[77]

144


Graph 26-1. Flexural Strength after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022.

Graph 26-2. Flexural Modulus after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022.

26: Polyarylamide

145

Graph 26-3. Notched Izod Impact Strength after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022.

Graph 26-4. Weight Change after Outdoor Exposure in Hiratsuka, Japan, for Solvay IXEF® 1002 and IXEF® 1022.

Chapter 27

Polycarbonate Category: Thermoplastic. General Properties: Polycarbonate (PC) is an amorphous thermoplastic with excellent toughness characteristics, clarity, and heat deflection properties. With the appropriate UV stabilization, PC can be used in products ranging from automotive parts to sunglasses.[87] •

GE Plastics Lexan® resin is a ‘water white’ material that is naturally transparent. It demonstrates light transparency close to that of glass and has a very high refractive index.

•

GE Plastics Lexan® SLX resin is a copolymer that has been derived from polyester carbonates and resorcinol arylates. When exposed to UV light, the copolymer undergoes a photoFries rearrangement and produces a new structure that is inherently a UV screener, essentially making the resin self-protecting.

•

Dow Calibre® resins are available with (outdoor applications) and without (indoor applications) UV stabilization packages.

Weathering Properties PC is used in building applications, mainly as glazing material. “When irradiated with short wavelength UV-B or UV-C radiation, polycarbonates undergo a rearrangement reaction (referred to as photo-Fries rearrangement). At low oxygen levels this reaction can yield yellow-colored products such as o-dihydroxy-benzophenones. But when irradiated at longer wavelengths (including solar visible

wavelengths) in the presence of air, polycarbonates undergo oxidative reactions that result in the formation of other yellow products. However, neither the detailed mechanisms nor the specific compounds responsible for the yellow coloration have been fully identified. Monochromatic exposure experiments on the wavelength sensitivity of several degradation processes of bis-phenol A polycarbonates have been reported recently.”[5] Lexan® resin may be sensitive to long-term exposure to UV light and weathering. The degree of sensitivity is very much dependent on the specific grade, the specified color, and the weathering conditions. Lexan® resin is ideally suited to a range of both indoor and outdoor applications. UV-stabilized Lexan® resin grades maintain high light transmission after prolonged UV exposure and offer good resistance to yellowing after prolonged exposure to harsh climatic conditions.[88] Lexan® resin can be additionally protected for applications in which they are exposed to critical environments of intense sunlight and high humidity. Tailor-made, glass clear, UV cap layers further improve the weathering resistance of extruded Lexan® sheet. For injection-molded parts a variety of coatings, including a range of GE Silicone hardcoats, enhance weathering, scratch, and abrasion resistance.[88] Lexan® SLX injection-molding grades, which are transparent, demonstrate (in laboratory testing) excellent weathering (more than seven years), high light transmission (>83%), and low haze (700*

0.25%

Phthalocyanine Blue

230

0.25%

Azo-Red

250

Organic Yellow (tetrachloroisoindolinone) TiO2 (stabilized, coated Rutile)

570

0.5% 0.5%

210

0.5%

500

Ultramarine Blue

0.5%

460

Iron Oxide

0.5%

Cd-Red

230

Cd-Yellow

175 0

100

200

Unpigmented 300

400

500

600

700

800

Arizona (kLy) Note: Polymer: HDPE (Ziegler). Base stabilization: 0.03% Irganox 1076 + 0.05% calcium stearate. Light stabilization: 0.15% Tinuvin 770. Polyolefin thick sections, Arizona 45◦ south (start November). Source: Ciba: Stabilization of Polyolefins—Part 2. *No sample left.

Graph 37-4. Tensile Strength after Arizona Exposure of 0.96 Density Unstabilized Polyethylene with Various Pigments.[112] 5000 1% Carbon Black 1% Iron Oxide


4000

1% Phthalocyanine Green 1% Cadmium Red

3000

1% Cadmium Yellow

2000 1% Phthalocyanine Blue 1% TiO2 (Rutile)

Natural

1000

1% TiO2 (Anatase) 0 0

6

12

18

24

30

Months Exposed in Arizona

36

40

Chapter 38

Low Density Polyethylene Category: Polyolefin, thermoplastic. General Properties: Low density polyethylene that contains UV stabilizers demonstrates significantly

better UV performance than unstabilized polyethylene but shows reduced tensile strength and elongation at break.

Chapter 39

High Density Polyethylene Category: Polyolefin, thermoplastic.

Weathering Properties: Colored Material Carbon Black It has been found that even low levels of carbon black impart such a high level of protection to the polymer that no other light stabilizers or UV absorbers are required. Several theories have been advanced to explain this phenomenon. Schonhorn and Luongo stated that the photo-oxidative stabilization of high density polyethylene (HDPE) filled with carbon black is due not only to the light shielding capability of carbon black but also to its moderately low surface energy. Another possibility is that since the antioxidant properties of surface phenolic groups on carbon black have been well characterized, increased stability may be obtained by the interruption of chain propagation. Regardless, compounds containing 0.5% carbon black have been exposed for 10,000 hours in a weatherometer with no loss in tensile strength.[115]

White Pigments The weathering resistance of several types of white colorants—zinc oxide, exterior rutile TiO2 , and indoor rutile TiO2 as well as anatase TiO2 — was compared. In all instances, 2% pigment was used in combination with 0.5% of a UV absorber. Anatase TiO2 and indoor rutile TiO2 were totally ineffective in protecting HDPE and have poorer performance than the natural stabilized resin. However, with exterior grade TiO2 UV protection is somewhat improved.[115] Zinc oxide on the other hand, provides excellent UV protection to polyethylene. The tensile

strength of the zinc oxide formulation is significantly better than the one containing 2% TiO2 . For best weathering results, zinc oxide can be used provided its hiding power is sufficient for the intended application. For high opacity film and thinwalled containers, TiO2 is a better choice, because the tint strength of zinc oxide is too low to provide sufficient opacity. Weathering performance of an exterior grade TiO2 , without UV absorber, and at three different pigment concentrations shows that a formulation containing 2% TiO2 has only 50% of the weathering resistance of one containing 2% TiO2 with 0.5% hydroxybenzophenone.[115] Such systems can be improved through the use of nickel and hindered amine light stabilizers (HALSs). Systems with nickel complex light stabilizers and HALSs are not significantly affected after 2000 hours of weatherometer exposure, as compared to the formulation containing a hydroxybenzophenone absorber.[115] Yellow Pigments To study the effect of yellow pigments on HDPE weatherability, three pigments were selected and incorporated at a 1% concentration in an ethylenebutene copolymer containing 0.5% of a UV stabilizer. The pigments chosen were cadmium yellow, lithopone yellow, and coated molybdate.[115] After weatherometer exposure for 8000 hours, cadmium yellow had the best performance, followed by coated molybdate, and then lithopone yellow. Increasing the concentration of coated molybdate and lithopone yellow improved the weathering performance of the compound, but increasing the cadmium yellow concentration decreased its overall weathering effectiveness. Since this phenomenon has been demonstrated repeatedly, an assumption can be made that a reaction must occur between the pigment and the stabilizer at higher pigment concentrations. Apparently, this does not happen, or at

196


least not as much, with coated molybdate or lithopone yellow pigment. The result of interaction of UV absorber and pigment, illustrated by the effect of UV stabilizer on 0.95 density polyethylene resin systems containing 1% and 2% cadmium yellow pigments, show that when no stabilizer is used the 2% system is somewhat better than the 1% cadmium yellow system. However, in formulations with stabilizer the opposite effect occurs.[115] To further study this interaction between stabilizers and cadmium yellow in a polyethylene system, samples were prepared containing two nickel complexes furnished by two suppliers. These nickel complexes are known to perform as light stabilizers, whereas hydroxybenzophenone was brittle at 10,000 hours of exposure. However, the 2% cadmium yellow system containing both nickel Complex A and B exhibited only a modest decrease in tensile strength after this same exposure period. The HALS would appear to be marginally better than the nickel complex but does not exhibit the green color inherent with nickel stabilizers. This further illustrates the complex interrelationships between stabilizers and pigments.[115] Both lithopone and cadmium yellow will fade during extended outdoor exposure. Although this is not a problem with single-pigment color formulations, the color change can be significant when cadmium yellow is combined with a more light stable pigment, such as ultramarine blue, to produce a green color.[115]

Red Pigments Of the three commonly used red pigments (quinacridone red, mercury-cadmium red, and lithopone red), the 1% quinacridone red formulation is found to be considerably better than either of the other two in 0.95 density stabilized polyethylene resins after 1000 hours of exposure in a weatherometer. There appears to be less difference between the lithopone red and the mercury-cadmium red pigments than between these pigments and the quinacridone red pigment.[115] The same relationship persists at a 2% pigment level. The 2% quinacridone red is still marginally better than the 2% mercury-cadmium red, and both are considerably better than 2% lithopone red after 10,000 hours of exposure. This indicates that as the

pigment concentration increases from 1% to 2%, mercury-cadmium red shows most improvement. Furthermore, the 1% quinacridone red pigment provides better stability than 2% lithopone red.[115] Previous studies have indicated that chemically pure (CP) cadmium red would offer virtually the same protection against UV degradation as mercurycadmium red. Although the quinacridone red and cadmium red pigments extend the outdoor weatherability of HDPE, they have limited use due to lack of color stability. The tint strength of both quinacridone and CP cadmium pigments will weaken when accelerated by a high humidity atmosphere. The most light stable red pigment is a combination of CP cadmium red and mercury-cadmium red pigments.[115] Earlier studies indicate that iron oxide is excellent for use in outdoor applications of HDPE. An unstabilized system of 0.5% iron oxide was virtually unchanged after 2000 hours in the weatherometer, while the tensile strength of 0.5% CP cadmium red started to decay considerably. Since both these formulations were unstabilized, this further demonstrates the significant screening effect of iron oxide in polyethylene. From past experience, iron oxide can be considered to be second only to carbon black in its ability to stabilize HDPE against UV degradation.[115]

Orange Pigments Four pigments at levels of 1% and 2% (coated molybdate, lithopone, CP cadmium, and mercurycadmium) in 0.95 density stabilized polyethylene were exposed for 10,000 hours in a weatherometer. At a concentration of 1%, CP cadmium orange appears to be 10–20% better than other pigments. Less difference can be seen among the pigments at the 2% level, although cadmium orange is still approximately 10% better than the others. It does appear that the coated molybdate pigment is somewhat better at 1% than at 2%, but this slight decrease falls within the experimental error range and can be considered negligible. The only pigment to show a significant difference between the two concentrations is lithopone orange. Since this pigment contains less cadmium than CP cadmium, the overall effect is quite the same as a reduced level of cadmium.[115] The effect of antioxidants on UV stabilization of 0.95 density stabilized polyethylene indicates that

197

39: High Density Polyethylene

the antioxidant system plays a major role in the outdoor performance of pigmented HDPE formulations. Two different types of antioxidants were compounded with a UV stabilizer and 1% and 2% cadmium orange. Antioxidant B imparted much more resistance to UV formulations with the proper antioxidants for outdoor applications.[115]

Blue and Green Pigments Phthalocyanine blue, cobalt blue, and ultramarine blue at a level of 1% were incorporated in an unstabilized polyethylene system and exposed for 2000 hours in a weatherometer. This test indicated that the phthalocyanine blue pigment provided two to three times as much UV protection as the ultramarine blue pigment. This level of protection in an unstabilized system is quite good. Cobalt blue, however, appears only moderately effective when compared to phthalocyanine blue.[115] It is also apparent that ultramarine blue imparts little or no protection to the polymer, since the performance of the compound containing ultramarine blue was a little better than natural HDPE. The same general trend is found in stabilized as well as unstabilized systems.[115] Many green formulations are prepared by combining ultramarine blue and cadmium yellow. Since the UV protection provided by ultramarine blue is poor, and only fair with cadmium yellow, it is not surprising that the combination is rather ineffective. Phthalocyanine green, however, imparts excellent UV resistance to polyethylene, as do some of the chrome greens. Compounds containing these pigments last longer than 6000 hours of weatherometer exposure with no loss of tensile strength.[115]

Pigment Dispersion Pigment dispersion is important in the compounding of any colored resin, since inadequate

dispersion can result in poor appearance, increased cost, and poor outdoor weatherability. To illustrate the effect of dispersion on weathering, three blends containing 0.5% CP cadmium red were prepared. Each of the blends was compared in order to achieve a good, fair, and poor pigment dispersion.[115] Tensile specimens from these compounds were aged in the weatherometer for 2000 hours. The tensile strength measured at 2 in./min (5 cm/min) showed very little difference between good/fair pigment dispersion. However, measurements at 20 in./min (50 cm/min) revealed that as pigment dispersion improved, there was a marked increase in tensile strength retention after UV exposure. As in the former case, the specimen with poor pigment dispersion was much less resistant to degradation than the good or even fair pigment system. These data clearly indicate that pigment dispersion is important to the UV resistance of a compound.[115] The degree of carbon black dispersion is also a determining factor in the effectiveness of a pigment for UV protection. Low levels of carbon black, properly dispersed, offer excellent UV protection. The usual condition is poor dispersion, normally compensated by using up to 2.5% black to give ultimate protection.[115]

Part Thickness The effect of part thickness plays a significant role in outdoor life. Since degradation of a part occurs from the exterior to the interior, the thicker the part, the greater the time required to penetrate to a depth that affects integrity. In one test, a 120 mil (3 mm) thick sample was found to have several times the life expectancy of a 30 mil (0.75 mm) sample of a yellow HDPE tested outdoors in Arizona.[115]

198


Weathering Properties by Material Supplier Trade Name Table 39-1. Tensile Strength after EMMA Accelerated Weathering of Chevron Phillips Marlex® HDPE with Channel Black and Furnace Black


199

Table 39-2. Tensile Strength after AcceleratedWeathering of Chevron Phillips Marlex® HDPE withVarious Degrees of Pigment Dispersion

200


Table 39-3. Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with UV Absorber and Various Orange Pigment Systems


201

Table 39-4. Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with 2% Cadmium Yellow Pigment

202


Table 39-5. Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with UV Absorber and Various Yellow Pigments


203

Table 39-6. Tensile Strength after Accelerated Weathering of Chevron Phillips Marlex® HDPE with 2% TiO2

204


Table 39-7. Surface and Appearance after Accelerated Weathering of Chevron Phillips Marlex® HDPE with UV Absorber, Various Antioxidants and Green Pigment


205

Graph 39-1. Tensile Strength after Arizona Outdoor Weathering of Yellow Chevron Phillips Marlex® HDPE.

Graph 39-2. Tensile Strength after Weatherometer Exposure of Yellow Chevron Phillips Marlex® HDPE.

206


Graph 39-3. Tensile Strength after Weatherometer Exposure of Red Chevron Phillips Marlex® HDPE.

Graph 39-4. Tensile Strength after Weatherometer Exposure of Unstabilized Red Chevron Phillips Marlex® HDPE.


207

Graph 39-5. Tensile Strength after Weatherometer Exposure of Orange Chevron Phillips Marlex® HDPE.

Graph 39-6. Tensile Strength after Weatherometer Exposure of Blue Chevron Phillips Marlex® HDPE.

208


Graph 39-7. Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with 2% Zinc Oxide and 2% TiO2 .

Graph 39-8. Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with Varying Concentrations of TiO2 .


209

Graph 39-9. Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with 1% TiO2 and UV Stabilizers.

Graph 39-10. Tensile Strength after Weatherometer Exposure of Chevron Phillips Marlex® HDPE with Various Degrees of Pigment Dispersion.

Chapter 40

Ultrahigh Molecular Weight Polyethylene Category: Polyolefin, thermoplastic. General Properties: Molecular degradation may be prevented through the addition of suitable light stabilizers. The light-stabilized Ticona GUR® ultrahigh molecular weight polyethylene samples showed no degradation even after a four-week exposure period; in other words, their physical characteristics were preserved. The property values were determined for

test specimens 1.3-, 10-, and 20-mm thick after exposure to a xenon-lamp device.[117] The addition of light-absorbing substances provides UV light resistance (e.g., 2.5% carbon black being the most commonly used additive). When the finished product cannot be black, satisfactory UV resistance (a minimum of five years) can be obtained with 0.5 wt% stabilizer.[118]

Chapter 41

Polyethylene Copolymers General Properties: Polyethylene copolymers such as ethylene-vinyl acetate copolymer, polyethyleneacrylic acid copolymer, and polyethylene-ionomer copolymer are polyolefins that are comparable to elastomeric materials in softness and flexibility.[111]

Weathering Properties These materials are resistant to radiation in the visible spectrum. If polyethylene and its copolymers are exposed for long periods outdoors, they are degraded by radiation at the UV end of the solar spectrum and by atmospheric oxygen. They are also degraded by other light sources with a high proportion of UV radiation. The degradation mechanism of oxidation combines with high temperatures and leads to a deterioration in the mechanical properties and, ultimately, to the destruction of the material.[119]

If moldings are intended for outdoor use, they must be adequately protected from UV radiation. By far the best UV stability is achieved by adding special grades of carbon black. Proportions of 2–3% improve UV stability by a factor of ten to fifteen. White and chromatic pigments may also improve the UV stability of polyethylene but can also adversely affect it.[119] If moldings in the natural color or in other hues have to display excellent outdoor performance and fastness to light, the copolymers can be supplied on request with special light stabilizers. Good results are obtained with hindered amine light stabilizers, in some cases in combination with benzotriazole compounds. They can increase the resistance to weathering by a factor of about two to four, the extent depending upon the conditions.[119]

214


Weathering Properties by Material Supplier Trade Name Table 41-1. Elongation Retained after Xenon Arc Weatherometer Exposure of Ethylene-Vinyl Acetate Polyethylene Copolymer Greenhouse Film

Chapter 42

Polypropylene Category: Polyolefin, thermoplastic. General Properties: Without added UV stabilizers, polypropylene has poor UV resistance.

Weathering Properties: Stabilization Polypropylene homopolymers and copolymers for automotive applications have traditionally been stabilized with a combination of hindered phenolic/ hindered phosphite process stabilizers and hindered amine light stabilizers (HALSs). In organic pigmented applications, the addition of a benzotriazole UV absorber enhances light stability and helps prevent the pigment from fading.[121] Car manufacturers strive to produce automobiles that will look and perform well for ten years. For aesthetic and styling reasons, manufacturers often partially paint molded-in color polypropylene. Thus light stabilizers must provide long-term stability and must not interfere with the adhesion of coatings to the substrate. Noninteracting NOR HALSs help polypropylene producers achieve both

outstanding long-term light stability and good adhesion to thermoplastic polyolefin surfaces.[121] Polypropylene geomembrane systems used in exposed (i.e., nonburied) applications are susceptible to cracks and other UV-induced damage. Stevens Geomembranes/JPS Elastomerics has conducted extensive UV resistance testing on polypropylene geomembrane sheets. Xenon arc weatherometer (ASTM G-26) exposure of the sheets tested exceeded 10,000 hours at 80◦ C (176◦ F) with no indication of visual surface deterioration. The results from extensive outdoor exposure testing in Florida and Arizona using EMMAQUA accelerated aging techniques (ASTM G-90) showed that the polypropylene geomembranes tested passed the 4 million langley (167,360 MJ/m2 total radiation) mark with no evidence of visual surface deterioration.[122] Table 42-1 correlates langleys to years of outdoor performance. “A” is the average langleys received per day, based on a five-year average (1966–1970) of global solar radiation on the earth’s surface, as received on a horizontal surface; data obtained from measurements reported by the US Weather Bureau. “B” is the number of years required to obtain 4 million langleys at the location indicated.[122]

216


Table 42-1. Conversions of EMMAQUA to Real-Time Performance by Geographic Location[122] Location

A

B

Albuquerque, NM

484

22

Argonne National Laboratory

327

34

Atlanta, GA

375

30

Cape Hatteras, NC

394

28

Fairbanks, AK

250

44

Grand Junction, CO

457

24

Los Angeles, CA

444

24

Miami, FL

451

24

New York, NY

323

34

Oak Ridge, TN

356

30

San Antonio, TX

411

26

Seattle/Tacoma, WA

307

36

42: Polypropylene

217

Weathering Properties by Material Supplier Trade Name Table 42-2. Tensile Strength after Florida and Puerto Rico Outdoor Weathering of Polypropylene Containing Various Antioxidant Stabilizers

218


Table 42-3. Mechanical Properties Retained after California and Pennsylvania Outdoor Weathering of Glass-Reinforced Polypropylene

42: Polypropylene

219

Table 42-4. Tensile Strength Retained after Puerto Rico Outdoor Weathering for Polypropylene Containing Antioxidants and UV Stabilizers

220


Table 42-5. Color and Gloss Changes after QUV Accelerated Weathering for Polypropylene Containing Microcal Calcium Carbonate and Pure Calcium Carbonate

Graph 42-1. Kilolangleys to 50% Retained Tensile Strength and Days to Embrittlement after 45◦ South Florida and Oven Aging at 120◦ C of UV-Stabilized Polypropylene Plaques.[121]

0.2% Tinuvin 770

0.2% Tinuvin 791

0.2% Chimassorb 944

600

400

200

kLys

0

200

400

600

Days

Note: Sample: 2 mm (80 mil) polypropylene plaques. Base stabilization: 0.15% Irganox B215 + 0.1% calcium stearate. Exposure: Florida 45◦ south and oven aging at 120◦ C. Test criteria: kilolangleys to 50% retained tensile strength + days to embrittlement.

221

42: Polypropylene

Graph 42-2. Surface Roughness after 45◦ South Florida Weathering Exposure of UV-Stabilized Polypropylene Plaques.[121] 1.2

Surface Roughness

1.0 0.4% Tinuvin 770 + 0.2% Tinuvin 328

0.8

0.6 Control 0.4 0.4% Tinuvin 791 + 0.2% Tinuvin 328

0.2

0

0

100

200

300

400

500

kLys Note: Sample: 2 mm (80 mil) polypropylene copolymer plaques. Base stabilization: 0.1% Irganox B225 + calcium stearate. Exposure: Florida 45◦ south. Test criterion: increase in kilolangleys to surface roughness.

Graph 42-3. Color Change, E, after Accelerated Weathering for UV-Stabilized Polypropylene Automotive Fibers.[124] 12 0.8% Chimassorb 944 10

0.8% Chimassorb 2020

∆E

8 6 4 2 0 0

113

301

602

902

1203

kJ Note: Samples contain 152/37 dtex, blue pigment. Base stabilization: Fiberstab® L112 + calcium stearate. Exposure: SAE J1885, WOM Ci65, 0.55 W/m2 at 340 nm, bpt 89◦ C.

Chapter 43

Polymethylpentene Weathering Properties

Category: Polyolefin, thermoplastic. ™

General Properties: Mitsui Chemicals TPX , a 4-methylpentene-1-based polyolefin, possesses many characteristics inherent in traditional polyolefins.

The weatherability of TPX™ is comparable with that of polypropylene.Although TPX™ is susceptible to UV deterioration, this can be virtually eliminated by adding UV stabilizers (MSW 303).[125]

Weathering Properties by Material Supplier Trade Name Graph 43-1. Izod Impact Strength Retained after Weatherometer Exposure for Mitsui TPX™ RT18 Polymethylpentene.

Chapter 44

Polyphenylene Sulfide Category: Thermoplastic. General Properties: Chevron Phillips Ryton® R-4-200NA is an advanced 40% fiberglass reinforced polyphenylene sulfide compound.

Weathering Properties by Material Supplier Trade Name Table 44-1. Material Properties Retained and Surface Erosion after Atlas Weatherometer Accelerated Weathering of Chevron Phillips Ryton® R4 Polyphenylene Sulfide

Chapter 45

General Purpose Polystyrene Category: Styrenic, thermoplastic. General Properties: General purpose polystyrene is available in various grades such as easy flow, intermediate flow, and high heat resins.

Weathering Properties Polystyrene undergoes light-induced yellowing upon exposure to UV light. Although the origin of the yellowing is not clear, the presence of air slows down the yellowing process. Yellowing is attributed to conjugated polyenes, various oxygenated species, or products of ring-opening reactions.[5] BASF Polystyrol® is stabilized against aging caused by exposure to atmospheric oxygen at elevated temperatures. Under normal light and temperature conditions indoors, parts made of Polystyrol® retain their appearance and functionality for years. The UV rays in direct sunlight are primarily responsible for damage outdoors. This aging shows up both as a gradual change in appearance (i.e., yellowing and loss of surface gloss) and as a decrease in the mechanical strength. Dark-colored products have better resistance than pale or transparent products.

For the above reasons, polystyrene is not recommended for articles that are used outdoors for a prolonged period. The yellowing resistance of polystyrene can be significantly improved by the addition of UV stabilizers.[128] Under the normal conditions of light and temperature encountered indoors, Polystyrol® moldings retain their appearance and perform their functions efficiently for many years.[129] Polystyrene foams generally have poor outdoor weathering resistance and are not recommended for long-term outdoor use. The plastic matrix deteriorates when exposed to direct sunlight for extended periods, as evidenced by a characteristic yellowing, loss of surface gloss, and by a decrease in mechanical strength. Darker formulations perform better than pale or transparent types.[130] To protect polystyrene foam against the effect of outdoor weathering and physical damage, an adequate coating should be applied on the surface.[130] Materials subjected to oxygen are degraded much faster in the presence of radiation than in its absence and vice versa. The discoloration of polystyrene occurs more rapidly when irradiation takes place in air or oxygen.[3]

Weathering Properties by Material Supplier Trade Name Table 45-1. Photo-Oxidation of Polystyrene[3] Oxygen Pressure (mm)

UV Radiation Time (hrs)

Oxygen in Product (%)

0

0

0.11

Nearly colorless

0

250

0.13

Light yellow

20

0

0.10

Nearly colorless

20

250

0.14

Yellow–orange

Note: The total exposure time is 250 hrs at 115–120◦ C in all cases.

Color

228


Table 45-2. Mechanical Properties Retained after California and Pennsylvania Outdoor Weathering of Glass-Reinforced General Purpose Polystyrene

45: General Purpose Polystyrene

229

Graph 45-1. Yellowness Index after Atlas Fadeometer Exposure of General Purpose Polystyrene.

Graph 45-2. Yellowness Index after Fluorescent Lamp Exposure of BASF Polystyrol® General Purpose Polystyrene.

Chapter 46

High Impact Polystyrene Category: Styrenic, thermoplastic. General Properties: High impact polystyrene (HIPS) is modified with polybutadiene elastomers. The high impact grades contain 6–12% of the elastomer. The elastomers are introduced into the base polymer to improve the impact resistance and deformation before fracture. Through the incorporation of different elastomers into the chain, products with a wide range of properties can be produced. NOVA Chemicals Styrosun® resins are weatherable HIPS specifically designed for use in outdoor applications. Styrosun® contains an inherently weather resistant rubber that is cross-linked and grafted into the polymer matrix. This unique polymer structure provides long-term color stability and physical property retention.[132]

Weathering Properties Unmodified HIPS resins usually experience greater change from outdoor exposure than general purpose polystyrene formulations. HIPS resins usually show less change than resins modified with ignition-resistant chemical additives.[133] Solar radiation, particularly at the UV end of the spectrum, acts together with atmospheric oxygen to cause embrittlement and yellowing. These changes occur mainly in the butadiene elastomer.[13] Styrosun® resins are resistant to sunlight and maintain significant physical properties after weathering. The weather resistant properties of Styrosun® resins are achieved by combining proprietary UV stabilization technology with an inherently UVstable impact modifier.[134] The key advantage of Styrosun® resin is the retention of physical properties after outdoor weathering. Applications using Styrosun® resins maintain functional product life and toughness after UV exposure.[134]

Molded plaques of Styrosun® and typical competitive outdoor polymers were exposed at four different locations in the United States and color retention (as E) was monitored over time. The color retention performance of Styrosun® HIPS, acrylonitrile-styrene-acrylate (ASA), UV-stabilized acrylonitrile-butadiene-styrene (UV-ABS), UVstabilized high impact polystyrene (UV-HIPS), and filled polypropylene (PP) was compared after 18 months at four different exposure sites in the United States. The results demonstrated that Styrosun® and ASA had equivalent performance (E range 4.9– 6.5). UV-ABS and UV-HIPS were also equivalent in performance (E range 18.5–26.1). Filled PP exhibited the smallest change in color over this exposure period (E range 1.6–2.2). A E value of 5 or less is generally considered to be negligible unless directly compared to an unexposed control.[132] Molded plaques of Styrosun® and various other materials were exposed in Xenon Arc WeatherOmeters® (ATLAS Material Testing Technology LLC) as per ASTM protocol G155 Cycle 2. By calculation, 3000 hours of accelerated weathering by this protocol is theoretically equivalent to one year of exposure in Florida or 0.8 years in Arizona. The color retention of white Styrosun® after 3000 hours of accelerated weathering was identical to its color retention after 18 months of Florida outdoor weathering. In this accelerated exposure test, neitherASAnor UV-ABS exhibited the same degree of color change seen after Florida exposure. However UV-ABS was again less resistant to color change than Styrosun® . Filled PP exhibited the smallest change in color over this exposure period. Examination of the accelerated weathering E graph also illustrates the significant amount of scatter in the data.[132] The samples were also tested for retained impact strengths. There are three impact results reported by a Dynatup® (Instron Corporation) impact test instrument. The “energy at maximum load” is the energy at the moment of impact, the “total energy”

232


is the energy required to break the test plaque, and the “maximum load” is the weight required to break the test plaque. When these absolute numbers were compared, in all cases Styrosun® was stronger and tougher than filled PP, but not as strong as UV-ABS. When the percentage retention values were compared, Styrosun® was found to retain its properties significantly better than UV-ABS and similar to filled PP.[132]

Addition of UV stabilizers overcomes the yellowing and brittleness associated with prolonged exposure of unmodified HIPS to sunlight.[132] Combinations of UV absorbors (UVAs) and hindered amine light stabilizers (HALSs) can provide improved performance.[135]

Weathering Properties by Material Supplier Trade Name Table 46-1. Color Change, E, after 18 Months of Florida Outdoor Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials Material Family

High Impact Polystyrene

Material Grade

NOVA Chemicals Styrosun® HIPS and Other Materials

Reference Number

132

Exposure Conditions

Florida, Arizona, Kentucky, Illinois

Exposure Time

18 months Styrosun®

Materials

3600

ASA

UV-ABS

UV-HIPS

Filled PP

SURFACE AND APPEARANCE E Florida

5.2

5.4

18.5

19.4

2.2

E Arizona

6.5

6.5

25.3

23.7

1.8

E Kentucky

5.0

4.9

24.2

22.0

1.6

E Illinois

5.8

4.8

26.1

23.1

1.6

Table 46-2. Color Change, E, after 18 Months of Florida Outdoor Exposure and 3000 hours of Accelerated Weathering for NOVA Chemicals Styrosun® HIPS and Other Materials Material Family


Material Grade


Reference Number

132

Exposure Conditions

Florida Outdoor Exposure

Exposure Time Materials

Accelerated Exposure

18 months Styrosun®

3600

3000 hrs

ASA

UV-ABS

Filled PP

5.4

18.5

2.2

Styrosun®

3600

ASA

UV-ABS

Filled PP

1.3

7.5

2.1

SURFACE AND APPEARANCE E

5.2

5.2

233

46: High Impact Polystyrene

Table 46-3. Impact Retention after 3000 hours of Accelerated Weathering for NOVA Chemicals Styrosun® HIPS and Other Materials Material Family


Material Grade


Reference Number

132

Exposure Conditions

Accelerated Exposure

Exposure Time Materials

3000 hrs Styrosun®

3600

Styrosun®

3600

UV-ABS

Filled PP

RETENTION OF ENERGY AT MAXIMUM LOAD Impact Retention (%)

80.7

102.7

39.1

107.2

88.3

76.9

42.9

135.1

88.4

82.6

28.2

98.1

RETENTION OF TOTAL ENERGY Impact Retention (%) RETENTION OF MAXIMUM LOAD Impact Retention (%)

Graph 46-1. Yellowness Index after Fadeometer Exposure of Dow Styron® Impact and Flame-Retardant Polystyrene and Dow Styron® Unmodified Polystyrene.

234


Graph 46-2. Color Change, E, after Florida Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials.[132] 25

FLORIDA 20

∆E

15

10

5

0 White Styrosun 3600 3 months

White ASA 6 months

White UV ABS 9 months

White UV HIPS

12 months

15 months

White filled PP 18 months

Graph 46-3. Color Change, E, after Arizona Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials.[132] 30

ARIZONA 25

∆E

20 15 10 5 0 White Styrosun 3600 3 months

White ASA 6 months


White UV HIPS

12 months

15 months


235


Graph 46-4. Color Change, E, after Kentucky Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials.[132] 30

KENTUCKY 25

∆E

20 15 10 5 0 White Styrosun 3600 3 months

White ASA 6 months


White UV HIPS

12 months

15 months


Graph 46-5. Color Change, E, after Illinois Outdoor Exposure of NOVA Chemicals Styrosun® HIPS and Other Materials.[132] 30

ILLINOIS 25

∆E

20

15

10

5

0 White Styrosun 3600 3 months

White ASA 6 months


White UV HIPS

12 months

15 months


236


Energy at Maximum Load (% Retention)

Graph 46-6. Impact Property Retention, Energy at Maximum Load, after 3000 hours of Atlas WeatherOmeters® Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials.[132] 140.0 120.0 100.0 80.0 60.0 40.0 20.0 0.0 0

500

1000

1500

2000

2500

3000

Exposure Time (hrs) UV ABS-BLACK

SSUN 3600 BLACK

SSUN 6600 BLACK

FILLED PP-WHITE

Graph 46-7. Impact Property Retention, Total Energy, after 3000 hours of Atlas Weather-Ometers® Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials.[132] 200.0

Total Energy (% Retention)

180.0 160.0 140.0 120.0 100.0 80.0 60.0 40.0 20.0 0.0 0

500

1000

1500

2000

2500

3000


SSUN 3600 BLACK

SSUN 6600 BLACK

FILLED PP-WHITE

237


Graph 46-8. Impact Property Retention, Maximum Load, after 3000 hours of Atlas Weather-Ometers® Exposure for NOVA Chemicals Styrosun® HIPS and Other Materials.[132]

Maximum Load (% Retention)

120.0 100.0 80.0 60.0 40.0 20.0 0.0 0

500

1000

1500

2000

2500

3000


SSUN 3600 BLACK

SSUN 6600 BLACK

FILLED PP-WHITE

Graph 46-9. Impact Strength after Xenon Arc Weathering of HIPS as per ISO 4692-2.[135] 80

Impact Strength (kJ/m2)

60 0.25% UVA 0.25% HALS 40

20

Control

0 0

250

500

750

1000

Exposure Time (hrs) Note: 2 mm plaques; base stabilization: 0.05% Irganox® 245; UVA:Tinuvin® P, Tinuvin® 327, or Tinuvin® 328; HALS:Tinuvin® 770, Tinuvin® 765, or Chimassorb® 119.

238


Graph 46-10. Yellowness Index after Xenon Arc Weathering of HIPS as per ISO 4892-2.[136] 20

Control

Yellowness Index

15

10

5

0

0.1% Tinuvin P 0.1% Tinuvin 770

0

1000

2000

3000

Exposure Time (hrs)

4000

5000

Chapter 47

Polysulfone Category: Thermoplastic. General Properties: Solvay Plastics Udel® polysulfone is an amorphous high performance polymer.

upon outdoor exposure. Weather resistance can be improved by the addition of carbon black. Protective paints or coatings can be used to preserve the properties of polysulfone articles exposed to direct sunlight.[137]

Weathering Properties Because of the aromatic ether backbone, polysulfone is susceptible to chemical degradation

Weathering Properties by Material Supplier Trade Name Table 47-1. Mechanical Properties Retained after Outdoor Weathering of Glass-Reinforced Polysulfone in California and Pennsylvania

240


Graph 47-1. Tensile Strength after Xenon Arc Weatherometer Exposure of Polysulfone.

Chapter 48

Polyethersulfone Category: Engineering thermoplastic. General Properties: Polyethersulfone (PES) is a heat-resistant, transparent, amber, noncrystalline engineering plastic.[138]

BASF Ultrason® moldings yellow and embrittle quickly when exposed outdoors. The moldings can be protected from degradation by the incorporation of carbon black, surface coating, or metallizing.[45]

Weathering Properties The weathering resistance of natural PES resin is not very good and therefore it is not suitable for outdoor use.[138]

Weathering Properties by Material Supplier Trade Name Graph 48-1. Tensile Strength after Xenon Arc Weatherometer Exposure of PES.

Chapter 49

Styrene-Acrylonitrile Copolymer Category: Thermoplastic. General Properties: The properties of BASF Luran® styrene-acrylonitrile (SAN) copolymer are primarily determined by the acrylonitrile content and the molecular weight or molecular weight distribution.

Weathering Properties The mechanical properties of Luran® specimens deteriorate after one or two years of outdoor exposure

(at an angle of 45◦ facing south in Ludwigshafen, Germany). The extent to which the mechanical properties are impaired depends on the nature of the specimen and the test procedure. Other consequences of outdoor exposure are yellowing and a rough surface. Luran® resins are also available in a UV-stabilized form. It can be seen that the rate of decrease in flexural strength is much less for Luran® resins containing UV stabilizers. Another advantage of UV stabilization is that the color retention is considerably improved.[139]

244


Weathering Properties by Material Supplier Trade Name Table 49-1. Surface and Appearance Properties after Arizona Outdoor Weathering of Dow Tyril® SAN Copolymer

Graph 49-1. Yellowness Index after Arizona Outdoor Weathering of Dow Tyril® SAN Copolymer.

49: Styrene-Acrylonitrile Copolymer

Graph 49-2. Yellowness Index after UV-CON Accelerated Weathering Exposure of SAN Copolymer.

245

Chapter 50

Styrene-Butadiene Copolymer Category: Styrene-butadiene, thermoplastic. General Properties: Chevron Phillips K-Resin® is a transparent styrene-butadiene copolymer that can be impact modified as well as UV stabilized.

Weathering Properties K-Resin® copolymers are styrenic copolymers that will yellow and ultimately craze and embrittle with long-term exposure to direct sunlight. Previous weatherometer testing shows that K-Resin® is susceptible to yellowing and physical property deterioration induced by UV light. With the addition of appropriate UV stabilizers, the estimated life of a K-Resin® part may be extended. In general, K-Resin® will withstand UV exposure for approximately three months before excessive brittleness and yellowing are evident. Modifying K-Resin® with commercially available UV stabilizers will extend the outdoor life of the material for up to eighteen months depending on the stabilizer package used.[142]

Indoor UV Light Resistance and Indirect Sunlight[142] K-Resin® polymers are used in many display applications that are often subjected to reduced levels of UV light, by indirect sunlight or fluorescent lighting. A study was conducted to determine the extent of K-Resin® yellowing under these conditions. Four samples evaluated in the test included KR01, KR03, and KR03 with two different UV stabilizers (Ciba Specialty Chemicals Tinuvin® P and Tinuvin® 770). Samples were prepared by adding 0.5% of each UV stabilizer to a K-Resin® sample by dryblending the sample prior to extrusion and palletizing. Tinuvin® P is a UV absorber and Tinuvin® 770 is a hindered amine light stabilizer. The clarity of these blends was

very good, but some slight yellow color developed when the UV stabilizers were initially added. The samples were compression molded into 15.24 mm plaques. One set was placed in a UVCON® tester, approximately 4 (10 cm) from a bank of four fluorescent lights. Another set was placed on a window ledge exposed to indirect sunlight. A third set was placed in a dark container so that the specimens were not exposed to any light source. Hunter “b” color was measured initially and at intervals of 3, 6, 12, 18, and 24 months. As expected, the non-UV stabilized KR01 and KR03 responded similarly in all circumstances. The UV-stabilized polymers demonstrated improved resistance to yellowing when exposed to UV light sources. When no light source was present, none of the K-Resin® samples yellowed appreciably over the two-year period. In the UV-CON® test, the most severe test, the addition of a UV additive improved the performance substantially. KR01 and KR03 unmodified samples discolored significantly between six and twelve months, and continued to further discolor with extended exposure. Tinuvin® P modified KR03 outperformed Tinuvin® 770 modified KR03, after two years, having about half as much yellow color development. In indirect sunlight, the modified KR01 and KR03 samples discolored most significantly after twelve months. The KR03 sample containing 0.5% Tinuvin® P performed better, with only minimal yellowing over the two-year test period. Tinuvin® 770 modified KR03 did not perform as well as Tinuvin® P modified KR03, discoloring significantly after twelve months. K-Resin® polymers, which will yellow when subjected to long-term exposure to direct sunlight, can also yellow with less severe UV exposure. Yellowing can be significantly reduced by the addition of UV stabilizers. Tinuvin® P is more effective than Tinuvin® 770 for fluorescent and indirect light exposure. K-Resin® parts stored in the dark showed no significant yellowing over at least a two-year period.

Chapter 51

Polyvinyl Chloride Category: Vinyl, thermoplastic.

Thickness

General Properties: PolyOne Geon® exterior compounds are UV stable and can withstand extreme weather conditions with good color and impact retention over time.

Degradation as a result of environmental exposure begins on the surface where radiation intensity is the greatest. The thicker sections provide a larger reservoir of stabilizers. The stabilizer readily, and constantly, migrates from the bulk to the film’s surface. Thus thicker films and sheets contain more of the preventative stabilizer, resulting in longer life.

Weathering Properties Of the synthetic polymers, polyvinyl chloride (PVC) is best known for its tendency to undergo photoyellowing. Yellowing is often the result of photothermal mechanisms that lead to the formation of conjugated polyenes. The rate of yellowing in the white profiles widely used in siding, window frames, and pipes can be slowed through the use of an opacifier, generally rutile titania. The reaction is localized in the surface layers of the polymer especially in opaque formulations used in building applications. The wavelengths that cause yellowing of PVC (the visible radiation >400 nm) also tend to cause photobleaching. Several possible photobleaching mechanisms are reported in the literature but the process is little understood.[11] The ability of plasticized PVC to withstand outdoor exposure is influenced by many factors. These include the flexibility and the thickness of the fabricated product as well as the additives that are incorporated into the formulation.[11] Testing has yielded the following recommendations: plasticizer concentration in the range of 35 parts per hundred parts of PVC, use of a good phosphate ester as 10% of the plasticizer system, use of some pigmentation, and incorporation of treated rutile titanium dioxide. UV light absorbers must be included in clear films. In addition to the epoxy and barium-cadmium-containing stabilizers, include a phosphate ester in the stabilizer system. The thicker the film, the longer will be its expected outdoor life.[11]

Plasticizers[11] All plasticizers, and all plasticizer concentrations, do not perform in the same manner. Generally, more volatile plasticizers will yield films with a shorter outdoor life expectancy. Clear films, including a UV absorber (UVA), plasticized at 50 phr (parts per hundred resin) were exposed in 4 mil (100 µm), 10 mil (250 µm), and 20 mil (500 µm) thicknesses in Florida. In this evaluation, four general-purpose plasticizers were studied: two were highly branched— diisodecyl phthalate (DIDP) and diisononyl phthalate (DINP), one was singly branched—dioctyl phthalate (DOP), and the fourth plasticizer—heptylnonyl-undecyl phthalate—was essentially linear. This study revealed the benefit of using the lessbranched phthalate plasticizers for products to be used outdoors. A prior, limited, outdoor weathering study in Florida showed 35 phr plasticizer to be the most beneficial for long-term durability. This was based on work using two plasticizer systems without UVA. One was DOP and the other plasticizer system was 90% DOP and 10% 2-ethylhexyl diphenyl phosphate. Also seen in this study was the synergistic influence of the phosphate plasticizer in thin films of 4 mil (100 µm) thickness. At the lower two concentrations, where films are relatively stiff, the increase in service life due to the addition of a phosphate plasticizer is 9–15%. Soft and flexible films, those with 50 and

250


Table 51-1. Exposure Results of Various Plasticized Films with Varying Thicknesses Plasticizer

Film Thickness

Exposure Time

Result

DIDP

4 mil (100 µm)

24 months

Entirely brown

DIDP

10 mil (250 µm)

30 months

Entirely brown

DIDP

20 mil (500 µm)

30 months

Entirely brown

DINP

4 mil (100 µm)

24 months

Entirely brown

DOP

4 mil (100 µm)

36 months

No browning

DOP

10 mil (250 µm)

36 months

No browning

DOP

20 mil (500 µm)

36 months

No browning

4 mil (100 µm)

36 months

No browning

10 mil (250 µm)

36 months

No browning

20 mil (500 µm)

36 months

No browning

Heptyl-nonyl-undecyl phthalate Heptyl-nonyl-undecyl phthalate Heptyl-nonyl-undecyl phthalate

Table 51-2. Outdoor Life of DOP-Plasticized 4 mil (100 µm) Thick Films with Varied Plasticizer Levels Plasticizer Level

Outdoor Life*

20 phr

13 months

35 phr

23 months

50 phr

15 months

70 phr

11 months

∗ Elongation

was the measure for outdoor life.

70 phr of plasticizer, have a dramatic increase in life expectancy. The addition of a small amount of phosphate plasticizer yields a 50% increase in outdoor serviceability. Later work from the same laboratory showed the response of films containing UVAs and plasticized at 50 phr to outdoor aging when the plasticizer system is varied from all DOP to all 2-ethylhexyl diphenyl phosphate. The optimum level of phosphate plasticizer was determined to be 10–15% of the total plasticizer system. The benefit of the phosphate synergism is seen in 20 mil (50 µm) thick films as well as in the thin 4 mil (100 µm) films.

Additional Plasticizers General performance monomerics diisodecyl glutarate (DIDG) and DOP were tested with polymerics G-4,000 (glutarate—viscosity, cps) and G-12,000 for yellowness index change after two, four, and six months of direct aging. Both monomerics show relatively high initial and longer-term tendencies to yellow. G-4,000 and G-12,000 provide excellent short-term and longer-term resistance to discoloration by yellowing. Glutarate polymerics in general have a proven history of providing good resistance to weathering for PVC compounds.[143]

251

51: Polyvinyl Chloride Table 51-3. Direct Weathering of Select Plasticizers in PVC[143] Yellowness Index Change Exposure Time

DIDG

DOP

G-4,000

G-12,000

2 months

8.25

4.93

0.17

0.5

4 months

9.25

8.93

3.17

1.5

6 months

14.9

9.85

4.55

5.35

Note: 45◦ south, with backing, South Miami. Recipe: PVC—100, BaCd—1, UV stabilizer—0.5, Plasticizer—67, ESO—3.

Table 51-4. Underglass Weathering of Select Plasticizers in PVC[11] Yellowness Index Change Exposure Time

DIDG

DOP

A-20,000

G-12,000

2 months

−1.9

2.36

−1.08

−2.83

4 months

2.94

6.05

0.57

−0.28

6 months

8.38

6.05

2.72

0.34

Note: 45◦ south, with backing, South Miami. Recipe: PVC—100, BaCd—1, UV Stabilizer—0.5, Plasticizer—67,ESO—3.

Underglass weathering net changes from initial yellowness values for monomerics DOP and DIDG and polymerics A-20,000 (adipate—viscosity) and G-12,000 were tested. The magnitude of short-term and longer-term yellowness index change values is lesser overall for the underglass-weathered compounds compared with those which were directly aged. Polymeric polyesters A-20,000 and G-12,000 provide about a threefold reduction in yellowness index change compared with the general performance monomerics.[11]

Stabilizers [11] When formulating flexible PVC films and sheets for outdoor use, the influence of the complete stabilizer system including epoxidized soybean oil, several metal salts of organic acids, a phosphate ester, and a UVA (2-hydroxy-4-methoxy benzophenone) must be considered. The influence of stabilizers on the outdoor durability of flexible PVC was measured using epoxycadmium stabilizers individually and in synergistic mixtures with 2-hydroxy-4-methoxy benzophenone.

“Epoxy-cadmium” is a synergistic mixture of an epoxy compound, a barium-cadmium salt of an organic acid, and a phosphate ester. When only the epoxy compound and barium-cadmium salt were used, decomposition occurred quite early, through discoloration, serious tack formation, and the loss of elongation. The addition of a UV light stabilizer, such as 2-hydroxy-4-methoxy benzophenone, had essentially no benefit. However, triphenyl phosphate by itself yielded a longer life than either of the above stabilizers. When 2-hydroxy-4-methoxy benzophenone was added to triphenyl phosphate, there was a large improvement in the weathering life of the film. Although the epoxy and barium-cadmium constituents were not necessarily needed to achieve good outdoor durability, they are definitely required to ensure adequate heat stability during the processing of flexible PVC.

Pigments and Colorants The outdoor life expectancy of flexible PVC may be improved through pigmentation.

252


Table 51-5. Titanium Dioxide in Films of Three Thicknesses Exposed in Florida[11] Thicknesses

TiO2

UVA

Time to Failure

4 mil (100 µm)

No

No

22 months

10 mil (250 µm)

No

No

22 months

20 mil (500 µm)

No

No

22 months

4 mil (100 µm)

Yes

No

32 months

10 mil (250 µm)

Yes

No

47 months

20 mil (500 µm)

Yes

No

76 months

Increasing quantities of anatase and rutile titanium dioxide improved the reflectance characteristics of plasticized PVC. Accelerated weathering studies revealed rutile titanium dioxide to be decidedly superior to anatase as a light-stabilizing agent.[11] It was found that “When an untreated rutile absorbs UV light, the absorbed energy goes into a photochemical reaction that liberates active oxygen.” For this reason, rutile that is used in plastics is given a surface treatment which inhibits this photochemical reaction and causes the absorbed UV energy to be dissipated as heat.[11] Colored pigments strongly assist in the maintenance of mechanical properties by protecting the plasticized PVC compositions from degradation. Combinations of pigments are beneficial for longterm outdoor aging because they can shield the visible and the UV range—thus the use of rutile titanium dioxide in combination with a selected colored pigment was found to provide quite good weathering resistance.[11] Similar outdoor studies were carried out with blue and black films. Both colorants, phthalocyanine blue at 0.9 phr and channel black at 1 phr, definitely extend the weathering life of flexible PVC films and sheets. The 20 mil (500 µm) blue film survived 80 months, over six and a half years, before failing the room temperature brittleness test.[11] The use of black pigments is encouraged to achieve the maximum outdoor life for flexible PVC products. The 20 mil (500 µm, 0.5 mm) sheets withstood five years of Florida exposure before reaching the 0◦ C brittleness temperature. Extrapolating this, a 60 mil (1.5 mm), black pigmented, flexible PVC sheet can withstand more than ten years of outdoor exposure in most environments.[11]

Yellowing PVC is susceptible to photoyellowing. “The photothermal mechanisms leading to the formation of conjugated polyenes that cause yellowing is well understood and documented in the literature. An opacifier (generally rutile titania) is used to slow down the rate of yellowing in white profiles widely used in siding, window frames, and pipes. The reaction is localized in the surface layers of the polymer especially in opaque formulations used in building applications. The activation energy for dehydrochlorination is reported to have a temperature coefficient of 8–18 kJ/mol, suggesting this process is readily enhanced at high temperatures. As with wool and paper, while the UV wavelengths cause yellowing of PVC, the visible radiation >400 nm tends to cause photobleaching. Several possible photobleaching mechanisms are reported in the literature but the process is little understood.”[5]

Weathering Properties: Stabilization Ciba® Tinuvin® XT 833 protects PVC from the harmful effects of light exposure and helps it maintain its initial appearance, initial tensile and elongation properties, and physical integrity during long-term weathering. In PVC roofing membranes, for example, it minimizes discoloration and embrittlement and enables the membranes to retain their moisture barrier properties and reflectivity. In some cases, studies show that even in an acidic environment Tinuvin® XT 833 can double the expected

253

51: Polyvinyl Chloride

lifetime of flexible PVC compared to UVAs. As PVC degrades, it releases hydrochloric acid which terminates the effectiveness of hindered amine light stabilizers (HALSs) as a light stabilizer or at leastseverely reduces HALS activity. Thus a unique class

of light stabilizers known as NOR HALSs (nonbasic HALSs) was developed. This completely new molecule is synthesized to function well in an acidic environment.[144]

Graph 51-1. Elongation after Xenon Exposure of Various UV Stabilized PVC Formulations.[144]

Elongation (%)

900 800

Tinuvin XT 833

700

Commercial PVC A

600

Commercial PVC B

500 400 300 200 100 0

0

6000

8000

Xenon Exposure (hrs)

Graph 51-2. Elongation Retention after Xenon Exposure of Various UV-Stabilized PVC Formulations.[144]

Elongation Retention (%)

80 70 60 50 40 30 20 10 0

2.0% UVA #1

2.0% UVA #2

Xenon Exposure (6000 hrs)

1.0% Tinuvin XT 833

254


Graph 51-3. Yellowness Index after Xenon Exposure of Various UV-Stabilized PVC Formulations.[144]

Yellowness Index

10 8 6

4

2 0

1.0% UVA #1

2.0% UVA #2

Xenon Exposure (8000 hrs)

1.0% Tinuvin XT 833

Chapter 52

Chlorinated Polyvinyl Chloride Category: Vinyl, thermoplastic. General Properties: Chlorinated polyvinyl chloride (CPVC) has physical properties similar to PVC, but offers higher heat deflection properties for extended temperature range uses.

Weathering Properties CPVC has reasonable weathering properties.[145]

Graph 52-1. Drop Weight Impact Strength Retained after Florida Outdoor Weathering Exposure of CPVC.

Chapter 53

ABS Polyvinyl Chloride Alloy Category: Acrylonitrile-butadiene-styrene (ABS) polymer, polyvinyl chloride (PVC) compounds, thermoplastic, vinyl. General Properties: Novatec Novaloy® 9000 is a specialty engineering alloy of ABS/PVC and has been formulated to provide excellent retention of physical properties upon aging.[147]

Weathering Properties Halogen-containing polymers (e.g., PVC) are relatively cheap and readily available materials. However, the weatherability (e.g., the light stability of halogen-containing polymers) is poor, leading to relatively short lifetimes, particularly in pigmented formulations.[148] The retention of mechanical and surface and appearance properties following exposure to an outdoor environment is important. Acrylic materials

generally have exceptional weathering performance. Blends of PVC and acrylic materials may be attractive in some situations.[148] For example, compared to unmodified acrylics, acrylics modified by the addition of PVC may be cheaper, have increased toughness, exhibit reduced flammability, and have desirable melt-flow properties. However, while the weathering performance of an acrylic/PVC blend is generally improved compared to PVC alone, the addition of PVC to acrylics reduces the weathering performance compared to unmodified acrylics. Thus, an acrylic/PVC blend may exhibit unacceptable color stability and degradation in appearance and mechanical properties following exposure to sunlight or in weathering tests. For unmodified pigmented acrylic/PVC blends the extent to which this “chalking” occurs is dependent upon the amount of PVC present in the blend, but even at concentrations of 50% elastomer. Most types of elastomers are difficult to process because they are cross-linked. But TPEs are rubbery without being cross-linked, making them easy to process.[166] Many TPEs are copolymers, a material made from two different constituents (monomers)—one of which is a rubber and the other a plastic. Because TPEs can be melted, they are recyclable. But because they form cross-links that are not permanent when they are cooled, this makes them rubbery.[166] There are two main kinds of TPEs, ionomers and block copolymers. An ionomer is a polymer that has a small number of ionic groups along its

backbone chain. A block copolymer is a polymer that has more than one section, or block. For example, a chain of SBS rubber is made of a short block of polystyrene followed by a longer block of polybutadiene, followed by another short block of polystyrene.[166] “The big difference between a cross-linked rubber and a thermoplastic elastomer is that in a crosslinked rubber the polymer chains are bonded to each other through covalent bonds, that is, the bonds that form when two atoms share a pair of electrons. In either type of thermoplastic elastomer, the polymer chains are held together by bonds that are weaker than covalent bonds. In the case of ionomers it is dipole-dipole interactions that bind the polymer chains to one another. In the block copolymer dispersion forces are at play. But in both ionomers and block copolymers, forces much weaker than those of the covalent bonding ‘cross-link’the polymer chains. Because much weaker forces are binding the chains together, breaking them apart is much easier, so easy that all it takes is the right amount of heat to separate the chains from each other, making the material processable again.”[167]

Chapter 61

Chlorinate Polyethylene Elastomer Category: Elastomer, thermoplastic, TPE. General Properties: Dow Chemical Company Tyrin® chlorinated polyethylene elastomer is often used as a modifier for PVC.[168]

Weathering Properties Modified PVC compounds made with Tyrin® show excellent resistance to weathering.[168]

Sunlight, ozone, and oxygen can commonly cause environmental degradation of many elastomers by attacking both saturated and (especially) unsaturated sites along the polymer chain. Because Tyrin products have a saturated molecular backbone, they are not as susceptible to such attacks as are many other elastomers.[169] Long-term exposures of properly formulated rubbers made with Tyrin elastomers have shown no cracking when tested in an ozone atmosphere or when exposed to outdoor weathering.[169]

Chapter 62

Olefinic Thermoplastic Elastomer Category: Elastomer, thermoplastic. General Properties: Thermoplastic olefins (TPOs) are generally

The Effect of UV Light and Weather, Second Edition: On Plastics and Elastomers, 2nd Edition

Handbook of Elastomers, Second Edition, (Plastics Engineering)

Fatigue and Tribological Properties of Plastics and Elastomers, 2nd Edition

Handbook of Thermoset Plastics, 2nd Ed., Second Edition (Plastics & Elastomers)

The effect of temperature and other factors on plastics and elastomers

Permeability properties of plastics and elastomers

Handbook of Plastics, Elastomers and Composites

Film Properties of Plastics and Elastomers

Corrosion of Polymers and Elastomers (Corrosion Engineering Handbook, Second Edition)

The Quantum Theory of Light, 2nd Edition

Introduction to Plastics Recycling: Second edition

Thermoforming: A Plastics Processing Guide, Second Edition

Functional Fillers for Plastics, Second Edition

Thermoforming: A Plastics Processing Guide, Second Edition

Mechanical and Corrosion-Resistant Properties of Plastics and Elastomers

Permeability and Other Film Properties of Plastics and Elastomers

Power And Its Disguises - Second Edition: Anthropological Perspectives on Politics, 2nd Edition (Anthropology, Culture and Society)

Hall-Effect Sensors, Second Edition: Theory and Application

Hall-Effect Sensors, Second Edition: Theory and Application

Plastics: Materials and Processing (3rd Edition)

Weather and Bird Behaviour, Third Edition

The iPod & iTunes Pocket Guide, Second Edition (2nd Edition)

Physics of Light and Optics, 2011c Edition

Plastics Technology Handbook, Fourth Edition (Plastics Engineering)

Mountain Weather and Climate, 3rd edition

Drugs and Drugs, 2nd Edition

Signals and Systems, 2nd Edition

Algorithms and Complexity, 2nd edition

Algebra and trigonometry, 2nd Edition

Science and Soccer, 2nd Edition

The Effect of UV Light and Weather, Second Edition: On Plastics and Elastomers, 2nd Edition

Handbook of Elastomers, Second Edition, (Plastics Engineering)

Fatigue and Tribological Properties of Plastics and Elastomers, 2nd Edition

Handbook of Thermoset Plastics, 2nd Ed., Second Edition (Plastics & Elastomers)

The effect of temperature and other factors on plastics and elastomers

Permeability properties of plastics and elastomers

Handbook of Plastics, Elastomers and Composites

Film Properties of Plastics and Elastomers

Corrosion of Polymers and Elastomers (Corrosion Engineering Handbook, Second Edition)

The Quantum Theory of Light, 2nd Edition

Introduction to Plastics Recycling: Second edition

Thermoforming: A Plastics Processing Guide, Second Edition

Functional Fillers for Plastics, Second Edition

Thermoforming: A Plastics Processing Guide, Second Edition

Mechanical and Corrosion-Resistant Properties of Plastics and Elastomers

Permeability and Other Film Properties of Plastics and Elastomers

Power And Its Disguises - Second Edition: Anthropological Perspectives on Politics, 2nd Edition (Anthropology, Culture and Society)

Hall-Effect Sensors, Second Edition: Theory and Application

Hall-Effect Sensors, Second Edition: Theory and Application

Plastics: Materials and Processing (3rd Edition)

Weather and Bird Behaviour, Third Edition

The iPod & iTunes Pocket Guide, Second Edition (2nd Edition)

Physics of Light and Optics, 2011c Edition

Plastics Technology Handbook, Fourth Edition (Plastics Engineering)

Mountain Weather and Climate, 3rd edition

Drugs and Drugs, 2nd Edition

Signals and Systems, 2nd Edition

Algorithms and Complexity, 2nd edition

Algebra and trigonometry, 2nd Edition

Science and Soccer, 2nd Edition

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