Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information LIQUID CRYSTALLINE POLYMERS SECOND EDITION The new edition of this authoritative guide on liquid crystalline polymer (LCP) science has been produced in response to the wealth of new material recently generated in the field. It takes the reader through the theoretical underpinnings to real-world applications of LCP technology in a logical, well-integrated manner. A chapter on liquid crystalline biopolymers has been introduced, whilst the in-depth discussion on applications describes not only maturing fields of high strength structural LCPs, but also a detailed analysis of the developing area of functional materials. The in-depth coverage and detailed glossary establish this as an indispensable text for graduate students and researchers in the polymer field, as well as being of interest to those working in chemistry, physics and materials science. A THENE D ONALD became Professor of Experimental Physics at the University of Cambridge in 1998 after many years as a lecturer and then reader. She was elected as Fellow of the Royal Society in 1999. She is the author of over 200 papers in the general field of soft matter physics, with interests spanning from synthetic to biologically relevant polymers. A LAN W INDLE is Professor of Materials Science at the University of Cambridge, Fellow of Trinity College, Cambridge, and Fellow of the Royal Society. He is the author of around 200 papers on polymer structure, LCPs and carbon nanotubes. He has previously held positions as head of the Materials Science department in Cambridge and director of the Cambridge MIT Institute. Professor Windle holds the Bessemer and Royal Society of Arts Silver Medal from Imperial College and was awarded the Rosenheim Medal by the Institute of Metals in 1988 and the Swinburne Gold Medal and prize by the Plastics and Rubber Institute in 1992. S IMON H ANNA is Lecturer in Polymer Physics at the University of Bristol. His research interests include computer simulations of structure–property relationships in polymers, liquid crystals and liquid crystal polymers, interfacial interactions between polymers and liquid crystals, and applications of polymers and liquid crystals in nanotechnology. © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information LIQUID CRYSTALLINE POLYMERS Second Edition A. M. Donald A. H. Windle University of Cambridge S. Hanna University of Bristol © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information cambridge university press Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, Tokyo, Mexico City Cambridge University Press Th e Edinburgh Building, Cambridge cb2 8ru, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9780521580014 © A. M. Donald, A. H. Windle and S. Hanna 2005 Th is publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2006 A catalogue record for this publication is available from the British Library isbn 978-0-521-58001-4 Hardback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. Information regarding prices, travel timetables, and other factual information given in this work is correct at the time of fi rst printing but Cambridge University Press does not guarantee the accuracy of such information thereafter. © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information Contents Preface to first edition page ix Preface to second edition xiii Part I Fundamentals 1 1 Liquid crystalline polymers: a brief history 3 1.1 From rigid-rods to main-chain polymers 3 1.2 The development of side-chain liquid crystalline polymers 5 1.3 New trends: networks and elastomers 6 1.4 Theoretical underpinnings 7 1.5 A bright future for liquid crystalline polymers 7 2Terminology and concepts 11 3 Stability of liquid crystalline polymers 68 3.1 Introduction 68 3.2 Factors limiting liquid crystallinity in rigid rod-like molecules 71 3.3 Control of mesophase stability in main-chain thermotropic liquid crystalline polymers 75 3.4 Lyotropic rigid-rod polymers 91 3.5 Polymers with mesogenic side-chains 101 3.6 Liquid crystalline polymers with more complex molecular architectures 111 4 Theories of liquid crystallinity in polymers 133 4.1 Introduction 133 4.2 Steric theory of rod-like liquid crystals 134 4.3 Virial theories: the Onsager approach 136 4.4 Flory’s lattice model 148 4.5 Orientation dependent interactions: the Maier–Saupe theory 161 4.6 Theories for main-chain polymers with semi-rigid chains 168 4.7 Theories of side-chain liquid crystalline polymers 193 4.8 Phenomenological theories of phase transitions 200 5 Local order and classification 229 5.1 Introduction 229 5.2 Nematic polymers 229 5.3 Cholesteric polymers 244 v © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information vi Contents 5.4 Smectic polymers 255 5.5 Other aspects of optical texture 274 5.6 Crystallisation in liquid crystalline polymers 277 6 Distortions and defects 292 6.1 Introduction 292 6.2 Distortions 292 6.3 Disclinations and point singularities: a general introduction 304 6.4 Disclination structure in planar geometry 305 6.5 Disclinations and point defects in three dimensions 315 6.6 Surface disclinations and walls 340 6.7 Defects in smectics and cholesterics 345 6.8 What is special about polymeric liquid crystals? 351 7 Biological liquid crystalline polymers 357 7.1 Introduction 357 7.2 Polyelectrolytes 358 7.3 Helicoids: also known as pseudomorphs 360 7.4 Lyotropic main-chain polymers 363 7.5 Side-chain liquid crystalline polymers 375 7.6 Concluding remarks 380 8 Flow and applied fields 385 8.1 Introduction 385 8.2 Flow fields in liquid crystalline materials 387 8.3 The Leslie–Ericksen theory for viscous flow of nematics 396 8.4 Miesowicz viscosities 399 8.5 The role of texture in liquid crystals subject to shear flow 402 8.6 Shear flow of liquid crystalline polymers 408 8.7 Mechanical response of liquid crystalline elastomers 417 8.8 Response of liquid crystalline polymers to electric and magnetic fields 422 8.9 Instabilities 430 Part II Applications 437 9 Processing and applications of structural liquid crystalline polymers 439 9.1 Two perspectives on the application of liquid crystalline polymers: an introduction to Chapters 9 and 10 439 9.2 Rheology 440 9.3 Processing and the consequences of flow alignment 457 9.4 Liquid crystalline polymers as structural materials 460 9.5 Liquid crystalline polymers in blends and composites 483 9.6 Commercial exploitation of structural liquid crystalline polymers 486 10 Applications of functional liquid crystalline polymers 504 10.1 Introduction 504 10.2 Liquid crystalline polymers as optoelectronic materials 504 10.3 Liquid crystalline polymers in displays 507 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information Contents vii 10.4 Semiconducting liquid crystalline polymers 516 10.5 Laser writeable devices 523 10.6 Non-linear optical applications 526 10.7 Sensors and actuators 540 List of symbols 549 Molecule index 558 General index 574 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-58001-4 - Liquid Crystalline Polymers: Second Edition A. M. Donald, A. H. Windle, and S. Hanna Frontmatter More information Preface to first edition Liquid crystalline polymers lead one into the heartland of interdisciplinary science, where it is an art in itself to thrive without becoming a Jack of all trades and master of none. To explore new frontiers requires depth, but in this subject probably more than any other there is need for a breadth of background, and often a breadth not catered for within the traditional divisions of school and college science education. The subject lies where organic chemistry, physical chemistry, physics and materials science meet. A physicist will discover the need to appreciate something of the chemical diversity of the molecular world, and will begin to become familiar with the chemical language of the trade. A chemist, skilled in the synthesis of new liquid crystalline molecules, will become increasingly familiar with the need of materials people for samples in kilogram rather than milligram quantities, and with the demands of the physicist that the samples be ever purer and better characterised.