Ring-Opening Polymerization. Kinetics, Mechanisms, and Synthesis

390 Pages·1985·5.863 MB·English

by  James E. McGrath (Eds.)

Ring-Opening Polymerization
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
ACS S Y M P O S I U M SERIES 286
Ring-Opening Polymerization
Kinetics, Mechanisms, and Synthesis
James E. McGrath, EDITOR
Developed from a symposium sponsored by
the Division of Polymer Chemistry
at the 187th Meeting
of the American Chemical Society,
St. Louis, Missouri,
April 8-13, 1984
American Chemical Society, Washington, D.C. 1985
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
Library of Congress Cataloging in Publication Data
Ring-opening polymerization.
(ACS symposium series, ISSN 0097-6156; 286)
"Developed from a symposium sponsored by the
Division of Polymer Chemistry at the 187th Meeting of
the American Chemical Society, St. Louis, Missouri,
April 8-13, 1984."
Bibliography: p.
Includes indexes.
1. Polymers and polymerization—Congresses.
I. McGrath, James Ε. II. America Chemical
Society. Division of Polymer Chemistry
Chemical Society. Meeting (187th
Mo.) IV. Series.
QD380.R56 1985 547.7 85-13352
ISBN 0-8412-0926-X
Copyright © 1985
American Chemical Society
All Rights Reserved. The appearance of the code at the bottom of the first page of each
chapter in this volume indicates the copyright owner's consent that reprographic copies of the
chapter may be made for personal or internal use or for the personal or internal use of specific
clients. This consent is given on the condition, however, that the copier pay the stated per
copy fee through the Copyright Clearance Center, Inc., 27 Congress Street, Salem, MA 01970,
for copying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This
consent does not extend to copying or transmission by any means—graphic or electronic—for
any other purpose, such as for general distribution, for advertising or promotional purposes,
for creating a new collective work, for resale, or for information storage and retrieval systems.
The copying fee for each chapter is indicated in the code at the bottom of the first page of the
chapter.
The citation of trade names and/or names of manufacturers in this publication is not to be
construed as an endorsement or as approval by ACS of the commercial products or services
referenced herein; nor should the mere reference herein to any drawing, specification, chemical
process, or other data be regarded as a license or as a conveyance of any right or permission,
to the holder, reader, or any other person or corporation, to manufacture, reproduce, use, or
sell any patented invention or copyrighted work that may in any way be related thereto.
Registered names, trademarks, etc., used in this publication, even without specific indication
thereof, are not to be considered unprotected by law.
PRINTED IN THE UNITED STATES OF AMERICA
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
ACS Symposium Series
M. Joan Comstock, Series Editor
Advisory Board
Robert Baker Robert Ory
U.S. Geological Survey
Martin L. Gorbaty
Geoffrey D. Parfitt
Exxon Research and Engineering Co.
Carnegie-Mellon University
Roland F. Hirsch
James C. Randall
U.S. Department of Energy
Phillips Petroleum Company
Herbert D. Kaesz Charles N. Satterfield
University of California—Los Angeles Massachusetts Institute of Technology
Rudolph J. Marcus W. D. Shults
Office of Naval Research Oak Ridge National Laboratory
Charles S. Tuesday
Vincent D. McGinniss
General Motors Research Laboratory
Battelle Columbus Laboratories
Douglas B. Walters
Donald E. Moreland
National Institute of
USDA, Agricultural Research Service Environmental Health
W. H. Norton C. Grant Willson
J. T. Baker Chemical Company IBM Research Department
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
FOREWORD
The ACS SYMPOSIUM SERIES was founded in 1974 to provide a
medium for publishing symposia quickly in book form. The
format of the Series parallels that of the continuing ADVANCES
IN CHEMISTRY SERIES except that, in order to save time, the
papers are not typeset but are reproduced as they are submitted
by the authors in camera-ready form. Papers are reviewed under
the supervision of the Editors with the assistance of the Series
Advisory Board and are selected to maintain the integrity of the
symposia; however, verbatim reproductions of previously pub­
lished papers are not accepted. Both reviews and reports of
research are acceptable
types of presentation
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
PREFACE
POLYMERIZATION REACTIONS CAN BE EASILY CLASSIFIED into either step-
growth (polycondensation) or chain-reaction (addition) polymerizations. In
the latter type, the reaction mechanisms that can be considered depend upon
the polymerization conditions and the structure of the monomer. Although
researchers have investigated many types of polymerizations, ring-opening
polymerizations, important fo hav bee relativel neglected
These polymerizations ca
reaction; the distinction is often a function of how molecular weight varies
with conversion. Polymers obtained by ring-opening polymerizations have
already found many important applications in industry. These applications
range from water-soluble materials that are useful as oil additives or in
cosmetics to reactive intermediates for segmented urethane or urea foams
and high-performance elastomers. Moreover, carpet fiber textile materials
and significant new biomaterials are also often based on ring-opening
polymerization.
The symposium upon which this book is based provided a comprehen­
sive discussion of ring-opening polymerizations; presentations by 12
international speakers were included in the 4-day sessions. Thus, the chapters
contained within this book should represent an up-to-date view of the entire
field of ring-opening polymerizations. The ideas discussed and results
tabulated herein should provide the basis for many additional academic
experiments as well as industrial research and product development in this
important area.
JAMES E. MCGRATH
Blacksburg, Virginia
January, 1985
ix
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
1
Ring-Opening Polymerization: Introduction
JAMES E. McGRATH
Department of Chemistry and Polymer Materials and Interfaces Laboratory,
Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
The principal purpose of this paper is to provide a suitable intro­
duction to the remaining 25 papers that comprise this book. As
mentioned earlier in the Preface this book is a result of a
symposium presented in
Division of the America
the symposium have chosen to prepare manuscripts to further
illustrate the research conducted in their own laboratories. A
minority of these speakers chose to publish their work elsewhere. We
have in fact been able to publish 26 of the 32 lectures which
represents a substantial majority of those presented at the meeting.
The range of topics discussed is quite broad and therefore should be
of considerable interest to many scientists and engineers in both
academic and industrial institutions around the world.
The subjects include fundamental and applied research on the
polymerization of cyclic ethers, siloxanes, N-carboxy anhydrides,
lactones, heterocyclics, aziridines, phosphorous containing
monomers, cycloalkenes, and acetals. Block copolymers are also
discussed where one of the constituents is a ring opening monomer.
Important new discussions of catalysis via not only the traditional
anionic, cationic and coordination methods, but related UV initiated
reactions and novel free radical mechanisms for ring opening
polymerization are also included.
It will be appropriate here to cite pioneering work in
establishing a number of the fundamental thermodynamic and kinetic
features associated with polymerization in general and ring opening
reactions in particular (1-35). Fortunately, Professor Ivin along
with Professor Saegusa have recently edited an excellent three­
-volume treatise on ring opening polymerization (1). In this book,
various experts in their own areas have contributed quite defini­
tive chapters on a number of the important polymerization aspects
related to ring opening reactions. The book thus provides an ex­
cellent survey of the state-of-the-art and many references up
through 1980 or perhaps later are included. Their important review
should thus be very complementary to the current book which should
be considered as more of a effort directed toward new research in
ring opening polymerization reactions. However, the availability of
0097-6156/ 85/0286-0001 $06.50/ 0
© 1985 American Chemical Society
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
2 RING-OPENING POLYMERIZATION
the Ivin/Saegusa book will be utilized in this introductory article
to illustrate a number of key points.
Ring opening polymerizations have led to a number of com­
mercially important materials, some of which are illustrated in
Scheme I. For example, polyoxymethylene is an important article of
commerce which can be prepared by the cationic ring opening of
trioxane X to yield the oxymethylene unit. In practice, these
materials are copolymers with minor amounts of ethylene oxide
included to stabilize the macromolecule end groups. The polymeri­
zation of ethylene oxide 3 to yield polyethylene oxide is an
example of the synthesis of an important water soluble macro-
molecule. Structure 4 currently produced at both low molecular
weights of a few hundred to a few thousand, as well as in very high
molecular weight, e.g. up into the millions (25). The closely
related polypropylene oxide is an important intermediate for poly-
urethane foams and the production of nearly all of the automobile
seating in the United State
ethers, based on tetrahydrofura
oxonium ion methods to yield polytetramethylene oxide 6 (PTMO).
Ordinarily this material is generated with dihydroxy end-groups and
is an important intermediate, not only for thermoplastic segmented
polyurethanes and ureas but also for the thermoplastic polyester
ether elastomers based upon polybutylene terephthalate and PTMO.
Lactones, such as ε-caprolactone, were one of the earliest ring
opening polymerizations studied by Carothers some 50 years ago (1).
At that point, it was demonstrated that the low melting behavior (Tm
~50°C) observed with this polymer meant that 8 would not be of
interest as a fiber. Relatively little further work was conducted
until the 1970fs, when ε-caprolactone monomer became an article of
commerce. Since that time, many interesting features such as the
biodegradability of 8 have been demonstrated, along with the fact
that it shows interesting compatibility behavior in blends with a
variety of other polymers. In addition, the ring opening polymeri­
zation of 7 can be initiated with diols or triols and hence im­
portant intermediates for polyurethanes are also made from this
material.
The polymerization of ε-caprolactam is one of the older and yet
extremely important examples of ring opening polymerizations. The
polyamide, commonly referred to as nylon-6, has many important
applications; perhaps the most important would be its application as
a textile fiber. It especially finds utility in textile carpeting
materials. From a structure property point of view, it is
interesting to note that the polyamide 10 has a crystalline melting
point of ~220°C relative to the low value of 50°C for its polyester
analog 8. This again was one of the major reasons for emphasizing
polyamides in early pioneering polymerization studies.
As a last example, we illustrate the ring opening polymeri­
zation of octamethyltetrasiloxane (D4) to yield polydimethyl-
siloxane. The linear polymer 12 is the basis of both silicone oils
at low molecular weights and silicone rubber at very high molecular
weights (M ξ 500,000). Of course, in order to provide for
w
vulcanization and enhance low temperature behavior, other units such
as methyl-vinyl and possibly diphenyl are also incorporated along
the chain, as will be discussed later in this brief review and in
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.
1. McGRATH Ring-Opening Polymerization 3
SCHEME I
Some Commercially Important Ring Opening Polymerizations
0
/ \
CHo CHo
I I -£cH-0}-
ο ο 2
\ /
CH
2
0
/ \
η CH-CH
2
-(•CH-CH2-CH2-CH2-0^-
2
^0-^CH >C>
2 n
"(CH )
2 5
7
0
II
ΗΝ I 4N-(-CH ^c)-
2 n
V(CH )5
2
10
CH3 CH3
-(•si—o}-
I *
CH3 CH3
11 12
In Ring-Opening Polymerization; McGrath, J.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1985.