Engineering Biopolymers Homopolymers, Blends, and Composites

Transcription

1 Stoyko Fakirov Debes Bhattacharyya Handbook of Engineering Biopolymers Homopolymers, Blends, and Composites

2 Fakirov / Bhattacharyya Handbook of Enginneering Biopolymers

3

4 Stoyko Fakirov Debes Bhattacharyya Handbook of Engineering Biopolymers Homopolymers, Blends and Composites Hanser Publishers, Munich Hanser Gardner Publications, Cincinnati

5 The Editors: Prof. Dr. Stoyko Fakirov, The University of Auckland, Department of Mechanical Engineering, Private Bag 92019, Auckland, New Zealand Prof. Dr. Debes Bhattacharya, The University of Auckland, Department of Mechanical Engineering, Private Bag 92019, Auckland, New Zealand Distributed in the USA and in Canada by Hanser Gardner Publications, Inc Valley Avenue, Cincinnati, Ohio , USA Fax: (513) Phone: (513) or Distributed in all other countries by Carl Hanser Verlag Postfach , München, Germany Fax: +49 (89) The use of general descriptive names, trademarks, etc., in this publication, even if the former are not especially identified, is not to be taken as a sign that such names, as understood by the Trade Marks and Merchandise Marks Act, may accordingly be used freely by anyone. While the advice and information in this book are believed to be true and accurate at the date of going to press, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Library of Congress Cataloging-in-Publication Data Handbook of engineering biopolymers: homopolymers, blends, and composites / [edited by] Stoyko Fakirov, Debes Bhattacharyya. p. cm. Includes bibliographical references and indexes. ISBN (hardcover) 1. Biopolymers--Analysis--Handbooks, manuals, etc. 2. Manufactures--Materials--Handbooks, manuals, etc. I. Fakirov, Stoyko. II. Bhattacharyya, Debes. TA455.P58H dc Bibliografische Information Der Deutschen Bibliothek Die Deutsche Bibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über < abrufbar. ISBN All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying or by any information storage and retrieval system, without permission in wirting from the publisher. Carl Hanser Verlag, Munich 2007 Production Management: Oswald Immel Coverconcept: Marc Müller-Bremer, Rebranding, München, Germany Coverdesign: MCP Susanne Kraus GbR, Holzkirchen, Germany Printed and bound by Druckhaus Thomas Müntzer GmbH, Bad Langensalza, Germany

6 The Authors and the Publisher dedicate this book to Professor Stoyko Fakirov for his 70 th anniversary in appreciation of his overall contribution to polymer science and technology

7 Prof. Stoyko Fakirov was born in January 1936, in a small village at the foot of the Balkan Mountains in Bulgaria. He went to elementary school there and attended high school in the neighboring town. In 1959, he earned an MS degree in Chemistry from Sofia University, Bulgaria, where he was immediately appointed Assistant Professor. Two years later, he started his PhD studies at the Lomonossov State University in Moscow, USSR, under the supervision of Academician V. A. Kargin. Stoyko Fakirov s thesis has been considered at that time as an important support of the Kargin s concept of a certain degree of ordering in amorphous polymers. In the early 1970s, Stoyko Fakirov acquired expertise in X-ray techniques while working with Prof. E. W. Fischer at the University of Mainz, Germany, as an Alexander von Humboldt Fellow. As a result of Fischer s and Fakirov s work, the unit cell parameters of PET were corrected (the new ideal density of g/cm 3 proved to be the most precise among all others suggested) and a more relevant structural model of PET was proposed along with a reasonable explanation of the multi-melting peak phenomenon. These results were very well received and amply cited by the international community of polymer scholars (3 papers with some 500 citations in total). In 1972, Stoyko Fakirov became Associate Professor. Having earned a DSc degree in 1982, in 1987 he was Full Professor in Polymer Chemistry at Sofia University. In the early 1980s, Prof. Fakirov worked on joint projects with Prof. J. M. Schultz at the University of Delaware, Newark, DE, USA. At that time he formulated and experimentally demonstrated the Chemical healing phenomenon based on solid state reactions in condensation polymers. This concept led to the formulation of the phenomenon of Chemically released diffusion, defined as mass transfer in solid and molten (mostly) polycondesates due to the continuously occurring interchange reactions between molecular segments. This idea of chemically released diffusion was later developed in greater detail by other polymer scientists. Prof. Fakirov s profound interest in transreactions in copolycondensates led to the clear definition and unambiguous experimental demonstration of Crystallization-induced sequential reordering in condensation copolymers, Melting-induced sequential reordering in condensation copolymers, and Miscibility-induced sequential reordering in condensation copolymers. Fakirov s definitions of these processes were not only well accepted and widely used, but were also proven correct through computer modeling and further experiments by Korean researchers.

8 In the 1990s, Prof. Fakirov worked on the microhardness of polymers with Prof. F. J. Baltá-Calleja in Madrid, Spain. In addition to writing a jointly published monograph, the two scholars suggested a simple Analytical expression between the glass transition temperature, T g, and microhardness of amorphous polymers, which allows for the calculation of microhardness without experimental measurements at any temperature below T g. Moreover, the relationship defined above leads to a more accurate account of the contribution of the soft (liquid) phase and/or component to the overall microhardness of complex bodies, which was previously accepted to be zero when the rule of mixtures was applied. At the same time, Reversible microhardness was demonstrated in cases of strain-induced polymorphic transitions in polymer crystals. Prof. Fakirov s studies of gelatin led to the formulation and demonstration of the rather unusual phenomenon of Melting of polymer crystals below T g of the same polymer. According to Prof. P. H. Geil the situation described is very unorthodox; yet, this phenomenon allows one to prepare highly ordered amorphous phases. In the past two decades, Prof. Fakirov focused primarily on a new type of polymer-polymer composites, namely, the Microfibril-reinforced composites (MFC) developed through international scientific cooperation. The concept was applied on an industrial scale at the Institute for Composite Materials at the University of Kaiserslautern, Kaiserslautern, Germany, where Prof. Fakirov and his former co-worker Prof. M. Evstatiev worked with Prof. K. Friedrich for a couple of years. Together with Prof. D. Bhattacharyya at the University of Auckland, Auckland, New Zealand, Prof. Fakirov is currently exploring the possibilities for a wider application of the MFC concept for commodity, technical and biomedical purposes. At the University of Auckland, Prof. Fakirov already applied this concept in the development of Nanofibrillar composites (NFC), yet another kind of polymer-polymer composites whose reinforcing elements are nanofibrils with diameters of nm. The latter can also be isolated in a neat form and used for the production of scaffolds in regenerative medicine or as carriers for controlled drug delivery, particularly when prepared from biodegradable and biocompatible polymers. Prof. Fakirov is co-founder of the polymer education program at Sofia University (with obligatory courses on polymers for all chemistry students) and founder of the Laboratory on Structure and Properties of Polymers at the same university. He was also Vice-Rector of Sofia University for 3 years. Worth mentioning awards bestowed to Prof. Fakirov are Humboldt Fellow (1971, 88) and Humboldt Research Prize Recipient (2000), Fellow of the Ministries of Education of Egypt, India, Spain, Turkey, and Portugal, Fellow of the Japanese Society for the Promotion of Science, of the US Information Agency, and of NATO Spain, and Member of the Advisory Board of the Institute for Polymer Research, Dresden, Germany. Additionally, he is a member of the Editorial Boards of three international polymer journals.

9 He has been a visiting professor at the University of Mainz (Germany), University of Delaware, Newark (USA), Bosphorus University, Istanbul (Turkey), University of Minho (Portugal), University of Kaiserslautern (Germany), CSIC, Madrid (Spain), and NJIT, Newark, NJ (USA). He is currently a visiting professor at the University of Auckland (New Zealand). Prof. Fakirov has published some 300 papers in reviewed polymer journals. He has 11 US patents and has contributed to 150 international polymer meetings, and delivered over 100 seminar talks world-wide. In addition, he has been the author, co-author, editor, or co-editor of, and always a contributor to 12 books on polymers including Oriented Polymer Materials (1996), Transreactions in Condensation Polymers (1999), Handbook of Thermoplastic Polyesters (2002), Handbook of Condensation Thermoplastic Elastomers (2005) (all four of Wiley-VCH, Weinheim), Microhardness of Polymers (2000), Cambridge University Press, London, Structure Development during Polymer Processing (2000), Kluwer, Dordrecht, Polymer Composites: from Nano- to Macro-Scale (2005), Springer, New York, Handbook of Engineering Biopolymers: Homopolymers, Blends and Composites (2007), Hanser Publishers, Munich, We sincerely wish Professor Stoyko Fakirov much health and success in his research going forward. Prof. D. Bhattacharyya (Co-Editor and Contributor) Prof. K. Friedrich (Contributor) Dr. Ch. Strohm (Publisher) Auckland, New Zealand Kaiserslautern, Germany Cincinnati, USA October, 2006

10 Preface Since Backeland created the very first entirely synthetic polymer about a century ago, the commercial production of such materials has increased enormously. From 1940 to 1980, the rate of polymer production grew by a factor of 100. This trend was still apparent in the year 2000 when the production of polymers increased by a factor of 4 in stark contrast to that of traditional materials; steel production grew by a factor of 2 while that of aluminum did not grow at all. Initially, synthetic polymers were thought of as a cheep replacement of common natural materials. Yet, in a few decades their unique properties were established and they were no longer considered interchangeable with natural materials. The singularity of synthetic polymers stems from the practically unlimited possibilities of manipulating their chemical composition and physical structure in order to obtain a product with specific properties. Nevertheless, under certain circumstances, the unique features of synthetic macromolecules can be a disadvantage. PET bottles for pressurized soft drinks are a pertinent example. The extreme resistance of PET to chemicals and solvents makes it a very attractive material for food packaging purposes, one to which there is no existing alternative so far. Once PET becomes a waste product, however, its chemical stability leads to very serious environmental problems. This disadvantage is a common feature of synthetic polymers. In the last few decades, steadily increasing efforts have been devoted to managing the problem of synthetic polymer wastes. Having observed that natural cellulose- and protein-based materials are biodegradable, polymer chemists have succeeded in producing synthetic biodegradable polymers. Unfortunately, for many reasons these products are still not widely used and the environmental impact of synthetic petroleum-based polymers remains very acute. One possible solution is using natural biopolymers and developing techniques for processing them with existing effective plastic processing equipment. Another option is blending synthetic polymers and natural biopolymers; yet another is using natural biopolymers as reinforcement in polymer composites, e.g., replacing glass fiber reinforcements of polymer composites with natural

11 fibers. Such studies are primarily driven by the fact that according to EU legislation, plastics used in car manufacturing (resulting in more than 5% ash residue after incineration) will be banned very soon. The aim of this project is to collect the results of studies around the world, focusing on the implementation of natural polymers as engineering plastics and the use of their inherent properties, namely biodegradability and harmless burning in combination with synthetic polymers. This book discusses the processing and, more extensively, the application of natural materials (celluloseand protein-based) as reinforcements of polymer composites. The structural, morphological, and thermal characteristics, as well as the mechanical behavior of the obtained materials are also pointed out. In addition, the book includes studies and results of commercial relevance. Furthermore, we discuss all natural polymers used in the blending or reinforcement of synthetic polymers in an attempt to cover the isolation, pretreatment, blending, and manufacturing of the respective materials. The preparation of biodegradable homopolymers, blends and composites involving chemical reactions (regardless of whether the starting material is petrochemical or natural organic), as well as microbial synthesis are beyond the scope of this book. We expect this book to be a step ahead in the direction set by the excellent work of E. S. Stevens Green Plastics. As the Editors of this volume, we have enjoyed working with the individual contributors and greatly appreciate their support, prompt response, and patience. This book could not have been put together without the continued support of Ms. S. Petrovich from Sofia University, who maintained contact with the contributors, polished the English, and helped in the processing of the manuscripts. For this we express our sincere gratitude. The Authors, Editors, and Publisher would like to thank all the publishers who generously gave their permission to reprint materials from their own editions. For more details, please see the end of the book. Last but not least, S.F. is grateful to the Foundation of Science and Technology of New Zealand, which made possible his sabbatical visit to the Centre for Advanced Composite Materials at the University of Auckland, Department of Mechanical Engineering, where this project was realized. S. Fakirov D. Bhattacharyya Auckland, November 2006

12 Contents PART I Chapter 1 INTRODUCTION Characterization of Natural Fibers K. G. Satyanarayana, F. Wypych 1.1. Introduction Methods of characterization Chemical aspects Physical properties Textile properties Mechanical properties Structural aspects Theoretical aspects Structural aspects Mechanical properties Weibull analysis Experimental results Chemical aspects Physical properties Mechanical properties Structural aspects Concluding remarks Acknowledgements References Appendix Chapter 2 Surface Modification of Natural Fibers: Chemical Aspects E. Maréchal 2.1. Introduction Surface treatment... 49

13 xii Contents 2.3. Specific characteristics of the chemistry of solid surfaces Control of the chemical changes Structural analysis of the fiber surfaces and their modifications Infrared spectroscopy UV spectroscopy X-ray electron spectroscopy Scanning electron microscopy Time-of-flight secondary ion mass spectroscopy Wide-angle X-ray spectroscopy Thermoanalytical techniques Inverse gas chromatography Contact angle measurements Mechanical analyses Chemical processes Reactions involved in the surface modification of natural fibers Treatment by alkaline bases Acylation Etherification Amidation Isocyanation Quaternization Silanization Grafting General comments and conclusions References PART II Chapter 3 POLYSACCHARIDE-BASED MATERIALS Starch for Injection Molding Purposes T. Czigány, G. Romhány, J. G. Kovács 3.1. Introduction Processing of starch Structure of starch Plasticization of starch Injection molding of thermoplastic starch Modification of thermoplastic starch properties Injection molding of thermoplastic starch for special applications Manufacturing and characterization of injection molded starch Materials and techniques Measurement results Injection molding simulation of thermoplastic starch... 98

14 Contents xiii 3.4. Conclusions and outlook Acknowledgements References Chapter 4 Plastics Filled with Tropical Starches: Mechanical Properties and Degradation Behavior Z. A. Mohd Ishak, R. Taib, U. S. Ishiaku 4.1. Introduction Plastics, utilization and environmental impact Degradable plastics, utilizations and challenges Starch-filled plastics Starch, availability, composition, structure, properties, and modification Research and development of tropical starch-filled plastics Mechanical properties Water uptake Enzymatic degradation Thermo-oxidative aging Natural weathering Soil burial Modeling and theoretical predictions of tensile properties Conclusions and future trends Acknowledgements References Chapter 5 Starch-Urethane Polymers: Physicochemical Aspects, Properties, Application T. Spychaj, K. Wilpiszewska, S. Spychaj 5.1. Starch as a biorenewable polymer feedstock Starch-urethane polymers via derivatization of hydroxyl groups Starch/polyurethane blends Chemical incorporation of starch into biodegradable polymers via urethane bonds Starch/polyurethane foams Conclusions References

15 xiv Contents Chapter 6 Plant-Based Reinforcements for Thermosets: Matrices, Processing, and Properties M. I. Aranguren, M. M. Reboredo 6.1. Introduction Resins Phenolic resins Epoxy resins Unsaturated polyester resins Vinyl ester resins Plant-based resins Processing methods Composite properties Particulate- and short fiber-reinforced composites Long fiber-reinforced composites Hybrid composites Effect of humidity on the materials properties Microbiological degradation Conclusions References Chapter 7 Pultrusion of Flax-Polypropylene Composite Profiles K. Friedrich, M. Evstatiev, I. Angelov, G. Mennig 7.1. Introduction Materials, manufacturing process, characterization Processing window and properties Conclusions Acknowledgements References Chapter 8 Natural and Man-Made Cellulose Fiber-Reinforced Composites K. P. Mieck, T. Reußmann, A. Nechwatal 8.1. Introduction Opening of cellulose natural fibers and manufacture of cellulose man-made fibers Natural fibers Cellulose man-made fibers