tailieunhanh - Recycling of Plastic Materials

Recycling of plastic materials is now an important field in the plastics industry, not just an activity born under environmental pressure. The recycling processes include industrial operations in which secondary materials are reprocessed and/or monomers recovered for further polymerization; such processes are termed secondary and tertiary recycling. | Recycling of Plastic Materials Francesco Paolo La Mantia Editor ChemTec Publishing Copyright 1993 by ChemTec Publishing ISBN 1-895198-03-8 All rights reserved. No part of this publication may be reproduced stored or transmitted in any form or by any means without written permission of copyright owner. No responsibility is assumed by the Author and the Publisher for any injury or and damage to persons or properties as a matter of products liability negligence use or operation of any methods product ideas or instructions published or suggested in this book. Printed in Canada ChemTec Publishing 38 Earswick Drive Toronto-Scarborough Ontario M1E 1C6 Canada Canadian Cataloguing in Publication Data Main entry under title Recycling of plastic materials Includes bibliographical references and index ISBN 1-895198-03-8 1. Plastics - Recycling. I. La Mantia F. P. Francesco Paolo 1993 C93-093134-3 i Table of Contents Poly ethylene terephthalate Film Recycling 1 Introduction 1 Direct Re-use 3 Re-use After Modification 6 Monomer Recovery 8 Methanolysis of PET-waste 8 Hydrolysis of PET-waste 8 Incineration 10 Bio- and Photo-degradation 11 Photodegradation 11 Biodegradation 12 Conclusive Remarks 13 References 14 The Importance and Practicability of Co-injected Recycled Poly ethylene terephthalate Virgin Poly ethylene terephthalate Containers 17 Introduction 17 Basic Technology 18 Manufacturing Process of Multilayer Bottles Containing Regrind 18 Drying of PET Resin and PET Flakes 18 Co-injection Molding of Virgin and Reground PET Flakes 21 Conditioning and Stretch-blow-molding 21 Double-layer Preforms 22 Trials of Co-injecting Virgin PET and Reground PET Flakes 22 Quality of the Raw Materials 22 The Trial Processing 24 Trial Results 24 Cost Savings 24 Contamination Aspects 24 Bacteriological Contamination 24 Contamination by Foreign Substances 25 Conclusions .