PREFACE his book is based on an international symposium on anionic polymeriza tion. The need for such a symposium grew out of discussions between myself and other members of the Polymer Division Executive Committee, about two years earlier. At that time I pointed out that we had not had a symposium dealing with the subject since 1962! Clearly, much new scien tific and important technological information had been generated since that time. Anionic polymerization dates back at least to the early part of this century. Indeed, sodium-initiated butadiene polymers were investigated as potential synthetic rubbers many years ago. Unfortunately, the derived, high 1,2 microstructure shows a T of about 0 ° C . Electron transfer initiators also were studied by Scott in 1936. The mid 1950's can be pinpointed perhaps as one of the golden eras of anionic polymerization (and, indeed, polymer science). Certainly, the discovery reported by Firestone that lithium-initiated polyisoprene had a structure quite similar to Hevea (natural rubber) should be noted. In addition, of course, one needs to comment on the important discovery by Professor Szwarc, M . Levy, and R. Milkovich that electron-transfer initia tion by alkali metal polynuclear aromatic complexes could produce nonterminated living polymers of predictable molecular weights. These novel macromolecular carbanions were further shown to be capable of initiating other monomers to produce well-defined block polymers and to undergo reactions with reagents (e.g. carbon dioxide and ethylene oxide) that could provide functional end groups. In 1957 the Phillips Petroleum Company commercialized perhaps the first styrene-butadiene diblock copolymers. Many groups around the world began to intensively investigate kinetics, mechanisms, and synthesis possibilities of anionic polymerization. Here one should at least mention Professor Morton and his students at Akron (which include myself), Drs. Bywater and Worsfold in Canada, Professor Rempp and his many colleagues in France, and Professor Schulz in Germany. Many other scientists have contributed also to what we currently know about the subject but space prevents us from reviewing their efforts.
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A few books and many reviews on anionic polymerization have appeared in the literature. Indeed, the contributors to the symposium and to this book also have written most of these! Briefly, one must cite the classic book of Professor Szwarc in 1968 and his later edited volumes on xi In Anionic Polymerization; McGrath, J.; ACS Symposium Series; American Chemical Society: Washington, DC, 1981.
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ion pairs. In addition, many of us have benefited from important reviews by Dr. Bywater and Professors Fetters and Rempp, among others. Cur rently, I am aware that Professor Morton has a new book that will be published soon. One of the most important discoveries relating to synthesis and physical behavior was made by Dr. Milkovich while at the Shell Develop ment Co. He and his colleagues showed that triblock copolymers containing polystyrene-polydiene-polystyrene blocks in appropriate sizes could behave as a physically cross-linked but linear thermoplastic elastomer. Thus Dr. Milkovich was involved with two very crucial discoveries in this field. Interestingly, he received his M . S. degree at Syracuse with Professor Szwarc and his Ph.D. at Akron with Professor Morton. I was pleased that Dr. Milkovich accepted my invitation to be a plenary speaker at the symposium, along with Professors Szwarc and Morton. The symposium was, and this book is, truly an international contribu tion. There are papers from Australia, Belgium, Canada, France, Germany, Japan, Kuwait, Poland, the United Kingdom, and the United States. Invitations also were sent to U.S.S.R. scientists, but, unfortunately, none could attend. Nearly all of the papers presented at the symposium are published in this book. A few manuscripts were not received or were withdrawn for various reasons. The publication time was somewhat longer than initially perceived. I take responsibility for this and thank those authors who submitted manuscripts very promptly for their patience! Those currently actively involved in anionic polymerization will recog nize that despite the extensive progress that has been made over the past 25 years, many kinetic, mechanistic, and even synthetic aspects have not been elucidated fully. Thus, it should not be surprising that there are opposing points of view. In the past, controversies have occurred, and although I tried to minimize this factor, I was not completely successful in this regard. However, I was pleased that all of the speakers came to the same room and also contributed to this volume. A few of the papers may be a bit strong; however, I have decided to let the scientific community come to their own decisions on these matters. This book contains very useful new work as well as critical reviews of specific areas. The scope is quite broad and ranges from ion pair structures to various features of the kinetics, mechanisms, and synthesis. Importantly, there are several fine industrial contributions that comple ment the academic studies. I hope that this book will be of interest and utility to students and scientists in academia, government, and industry. I would like to thank all of the authors for their contributions to this book. I also would like to gratefully acknowledge the invaluable assistance of the ACS staff. Finally, the secretarial expertise provided by Debbie Farmer and Donna Perdue was indispensable. xii In Anionic Polymerization; McGrath, J.; ACS Symposium Series; American Chemical Society: Washington, DC, 1981.
The financial support of the symposium by The Firestone Tire and Rubber Co., Gulf Oil Chemicals Co., the 3M Co., the Shell Development Co., and the Polymer Materials and Interfaces Laboratory of our Univer sity was extremely helpful.
JAMES E. MCGRATH Chemistry Department and Polymer Materials and Interfaces Laboratory Virginia Polytechnic Institute and State University Downloaded by CAPE BRETON UNIV on March 16, 2013 | http://pubs.acs.org Publication Date: November 30, 1981 | doi: 10.1021/bk-1981-0166.pr001
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xiii In Anionic Polymerization; McGrath, J.; ACS Symposium Series; American Chemical Society: Washington, DC, 1981.
