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<ul><li><p>Plastics Processing Data</p><p>Handbook</p><p>Second edition</p><p>Dominick V. Rosato, P.E.Rhode Island School of DesignChatham, MA, 02633USA</p><p>CHAPMAN &amp; HALLLondon Weinheim New York Tokyo Melbourne Madras</p></li><li><p>Published by Chapman &amp; Hall, 2-6 Boundary Row,London SEl 8HN, UK</p><p>Chapman &amp; Hall, 2-6 Boundary Row, London SEl 8HN, UKChapman &amp; Hall GmbH, Pappelallee 3, 69469 Weinheim, GermanyChapman &amp; Hall USA, 115 Fifth Avenue, New York, NY 10003, USAChapman &amp; Hall Japan, ITP-Japan, Kyowa Building, 3F, 2-2-1Hirakawacho, Chiyoda-ku, Tokyo 102, JapanChapman &amp; Hall Australia, 102 Dodds Street, South Melbourne, Victoria3205, AustraliaChapman &amp; Hall India, R. Seshadri, 32 Second Main Road, CIT East,Madras 600 035, India</p><p>First edition published by Van Nostrand Reinhold 1990Reprinted by Chapman &amp; Hall 1995.Second edition 1997 1997 Dominick V. RosatoTypeset in 10/12 Palatino by Best-set Typesetter Ltd., Hong KongPrinted in Great Britain by The University Press, CambridgeISBN O 412 80190 6Apart from any fair dealing for the purposes of research or private study,or criticism or review, as permitted under the UK Copyright Designs andPatents Act, 1988, this publication may not be reproduced, stored, ortransmitted, in any form or by any means, without the prior permissionin writing of the publishers, or in the case of reprographic reproductiononly in accordance with the terms of the licences issued by the CopyrightLicensing Agency in the UK, or in accordance with the terms of licencesissued by the appropriate Reproduction Rights Organization outside theUK. Enquiries concerning reproduction outside the terms stated hereshould be sent to the publishers at the London address printed on thispage.</p><p>The publisher makes no representation, express or implied, withregard to the accuracy of the information contained in this book andcannot accept any legal responsibility or liability for any errors oromissions that may be made.A catalogue record for this book is available from the British Library</p><p> Printed on permanent acid-free text paper, manufactured in accord-ance with ANSI/NISO Z39.48-1992 and ANSI/NISO Z39.48-1984(Permanence of Paper).</p></li><li><p>Preface</p><p>This second edition modifies and updates the previous book with moreconcise and useful information which interrelates processes with plasticmaterials7 product requirements, and costs. It includes more details on thedifferent processes and continues to simplify the understanding of howplastics behave during processing. The past few years have seen thecontinuing development of many advances in plastic materials and corre-sponding advances in processing techniques.</p><p>This book has been prepared with an awareness that its usefulness willdepend greatly upon its simplicity. The overall guiding premise has there-fore been to provide all essential information. Each chapter is organized tobest present a methodology for processing with plastics.</p><p>This comprehensive book is useful to those in any industry to expandtheir knowledge in one or more processes. It has been prepared to beuseful to those using plastics as well as those contemplating their use. Tothis end, the presentations are comprehensive yet simplified, so that eventhe specialist will obtain useful information.</p><p>The book may be used and understood by people in fabrication andproduction, design, engineering, marketing, quality control, R&amp;D, andmanagement. Sufficient information is presented to ensure the reader hasa sound understanding of the principles involved, and thus recognizeswhat problems could exist, or more importantly, how to eliminate orcompensate for potential problems. Knowledge of all these processingmethods, including their capabilities and limitations, helps one to decidewhether a given product can be fabricated and by which process.</p><p>Many guidelines are provided for maximizing plastics processing effi-ciency in the manufacture of all types of products, using all types ofplastics. A practical approach is employed to present fundamental yetcomprehensive coverage of processing concepts. The information anddata presented by 290 figures and 137 tables relate the different variablesthat affect the processes listed in the table of contents.</p></li><li><p>The text presents a great number of problems pertaining to differentphases of processing. Solutions are provided that will meet product per-formance requirements at the lowest cost. Many of the processing vari-ables and their behaviors in the different processes are the same, as theyall involve the basic conditions of temperature, time, and pressure. Thebook begins with information applicable to all processes, on topics such asmelting, melt flow, and controls; all processes fit into an overall schemethat requires the interaction and proper control of systems. Individualprocesses are reviewed to show the effects of changing different variablesto meet the goal of zero defects. The content is arranged to provide anatural progression from simple to complex situations, which range fromcontrol of a single manually operating machine to simulation of sophisti-cated computerized processes which inteface with many different pro-cessing functions.</p><p>Many of the procedures used in an individual process are identical orsimilar to those of other processes. A reader interested in a process cangain a different perspective by reviewing other processes. When an obvi-ous correlation exists, a cross-reference is made to the other processes.Other pertinent information includes processing guidelines for trouble-shooting, etc.</p><p>Both practical and theoretical viewpoints are presented. Persons deal-ing with practicalities will find the theoretical explanations enlighteningand understandable. And theorists will gain insight into the practicallimitations of equipment and plastics (which are not perfect). The variousprocess limitations are easily understood.</p><p>Processing is interdisciplinary. It calls for the ability to recognize situa-tions in which certain techniques may be used and to develop problem-solving methods to fit specific processing situations.</p><p>It is important to reemphasize that all the data on plastic properties areto be used as guides. Obtain the latest, most complete data from materialsuppliers and data banks.</p><p>Information contained in this book may be covered by US and world-wide patents. No authorization to utilize these patents is given or implied;they are discussed for information only. Any disclosures are neither alicense to operate nor a recommendation to infringe any patent. No at-tempt has been made to refer to patents by number, title, or ownership.</p><p>As trade and competition increase throughout the world, maintaining acompetitive advantage depends on the ability to use the technology con-tained in this book most efficiently and bring the advanced technologiesrapidly to the marketplace.</p><p>D. V. RosatoWaban, MA, USA</p><p>October, 1996</p></li><li><p> v This page has been reformatted by Knovel to provide easier navigation. </p><p>Contents </p><p>Preface ................................................................................... xvi </p><p>1. Fundamentals ................................................................. 1 Introduction .................................................................................... 1 Product Requirements and Machine Performance ...................... 6 Processing Fundamentals ............................................................ 8 Processability ................................................................................ 8 Processes ...................................................................................... 9 </p><p>Overview ........................................................................... 9 Processing and Properties ................................................ 12 Processing Methods ......................................................... 14 Machine Operation Terminology ....................................... 14 Plastics Memory and Processing ...................................... 14 Drying Plastics .................................................................. 21 Air Entrapment .................................................................. 27 Release Agents ................................................................ 27 Heat History, Residence Time, and Recycling .................. 28 Heat Profile ....................................................................... 29 Processing and Tolerances ............................................... 30 Screw Plasticating ............................................................ 34 Intelligent Processing ........................................................ 35 Processing Diagrams ........................................................ 35 Selecting a Process .......................................................... 37 </p></li><li><p>vi Contents </p><p> This page has been reformatted by Knovel to provide easier navigation. </p><p>Plastic Materials ............................................................................ 49 Introduction ....................................................................... 49 Molecular Properties ......................................................... 54 Thermoplastics ................................................................. 55 Thermosets ....................................................................... 57 A-, B- and C-Stages .......................................................... 59 Properties Influencing Processes ...................................... 59 Melt Flow and Rheology ................................................... 77 Thermal Properties ........................................................... 85 Degradation ...................................................................... 93 Orientation: Defect or Benefit? .......................................... 93 Density and Specific Gravity ............................................. 98 Selecting Plastics .............................................................. 98 </p><p>Product Design .............................................................................. 103 Design Features That Influence Processing and </p><p>Performance ............................................................. 106 Process Controls ........................................................................... 112 </p><p>Temperature Controls ....................................................... 115 Timing and Sequencing .................................................... 115 Screw Speed Control ........................................................ 116 Weight, Thickness, and Size Controls ............................... 116 Microprocessor Control Systems ...................................... 116 Problems in Process Controls ........................................... 117 </p><p>Processors ..................................................................................... 118 Custom ............................................................................. 118 Captive ............................................................................. 118 Proprietary ........................................................................ 119 </p><p>Advantages and Disadvantages ................................................... 119 Troubleshooting ................................................................ 119 </p></li><li><p>Contents vii </p><p> This page has been reformatted by Knovel to provide easier navigation. </p><p>2. Injection Molding ............................................................ 121 Basic Process ................................................................................ 121 </p><p>Machine Characteristics .................................................... 124 Machine Types ................................................................. 126 Machine Variables ............................................................ 127 Productivity and Cycle Time .............................................. 128 Material Movement and Setup .......................................... 129 </p><p>Screw/Barrel Performance ............................................................ 135 Mixing Devices .................................................................. 139 Barrier Screws .................................................................. 140 Custom-Designed Screws ................................................. 140 Mechanical Requirements ................................................. 142 Valves and Screw Tips ..................................................... 142 Vented Barrels .................................................................. 143 Air Entrapment .................................................................. 147 Shot-to-Shot Variation ....................................................... 147 Purging ............................................................................. 149 Wear ................................................................................. 151 Output ............................................................................... 152 </p><p>Clamping ....................................................................................... 152 Basic Types ...................................................................... 152 Different Systems ............................................................. 156 Clamping Forces ............................................................... 157 </p><p>Tie-Bar Growth .............................................................................. 158 Hydraulic and Electric IMMs ......................................................... 158 Molds ............................................................................................. 160 </p><p>Types ................................................................................ 164 Runner Systems ............................................................... 171 Other Considerations ........................................................ 174 Mold Guides ..................................................................... 176 </p></li><li><p>viii Contents </p><p> This page has been reformatted by Knovel to provide easier navigation. </p><p>Process Controls ........................................................................... 176 Computer-Integrated Injection Molding ......................................... 179 </p><p>Microprocessor Control Systems ...................................... 179 Process Simulations ......................................................... 180 Improving Performance ..................................................... 180 </p><p>Molding Variables Versus Performance ....................................... 180 Melt Flow Behavior ........................................................... 180 Parting Lines ..................................................................... 186 Back Pressure .................................................................. 187 Screw Bridging ...............</p></li></ul>