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Book reviews
novel organic polymer materials with predetermined
properties. Such techniques include the synthesis,
kinetics and thermodynamics of macromolecular
organization.
The book consists of four articles reviewing the
literature based on the authors' own experiences over
the last decade. It does not claim to be exhaustive nor
to provide complete coverage of all literature in this
®eld. Instead, it focuses on the currently interesting
areas of research, notably living polymerization, block
copolymer synthesis, synthesis of dendrimers and
macroporous thermosets.
In the ®rst chapter by P Dubois and D Mecerreyes,
recent developments in the macromolecular engineering of aliphatic polyesters are reviewed. Aluminiumalkoxide-controlled living ring-opening polymerization of cyclic (di)esters, ie lactones, lactides and
glycolides, is described. This so-called `coordination±
insertion' mechanism, and the ability of this living
polymerization process to prepare well-de®ned homopolymers, are then discussed. Because of this synthetic
breakthrough, a variety of novel materials have been
developed with versatile applications in very different
®elds, such as biomedical and microelectronics. In
Chapter 2, J L Hedrick describes an approach to
modify polyimides with minimal sacri®ce of their
desirable properties. Preparation of block and graft
copolymers provides a means of tailoring the morphology and properties of polyimides by judicious
choice of the coblock±coblock composition, molecular
architecture, and block lengths. The advent of the
poly(amidoalkyl ester) intermediate to the polyimide
allows the isolation and characterization of the
copolymers before imidization. Such systems represent self-assembling arrays with considerable potential
for the preparation of nanostructures. This chapter
describes the modi®cation of rigid and semi-rigid
polyimides by copolymerization to address favorably
such issues as residual thermal stress, dielectric
constant, auto-adhesion and other key design criteria.
In Chapter 3, C Hawker describes the synthesis of
dendritic macromolecules by both the convergent or
divergent growth approaches, with emphasis on the
controlled manipulation of three-dimensional structure. The utility of these techniques in preparing a
wide variety of different dendritic structures is then
discussed in terms of the three distinct building blocks,
and the chain-ends. Control of these regions, coupled
with changes in the synthetic approach, gives tailormade dentritic macromolecules with predetermined
physical properties and/or function. The application of
current spectroscopic methods to the structure elucidation of dentritic structure on the physical properties
of these novel materials is described. Finally, a
comparison is made with the related class of highly
branched polymers, hyperbranched macromolecules,
and the manipulation of structure±function for these
materials is examined.
Macroporous polymers are treated in detail in the
fourth chapter by J Kiefer, focusing on prediction of
Polym Int 49:235±238 (2000)
phase behaviour and preparing thermosetting materials. The formation of porous polymers is initially
classi®ed into methods of gas blowing, emulsion
derived and phase separation. In chemically induced
phase separation involving a reactive polymer precursor and a solvent, the phase separation is driven by
the change in free energy of the system given by
changes in enthalpy and entropy. Guidelines based on
the component molecular structure are given for the
prediction and veri®cation of phase behaviour, and
hence the ®nal porous morphology. The in¯uence of
the kinetics is followed by processing the two-phase
polymer±liquid to give either isolated or co-continuous
porosities. Finally, the in¯uence of dispersed liquid
droplets or voids on polymer thermoset fracture
properties is discussed, with a section on the lowering
of dielectric constant through void incorporation.
F Schué
Experimental strategies for polymer scientists
and plastics engineers
RC Neuman
Hanser, Munich, 1997
pp ix ‡ 154, price DM88.00
ISBN 3-446-1862-8
The stated objective of this book is to provide a guide
to the design of effective experimental strategies for
those who have received no formal training in
experimental design, statistics or data analysis
methods. Following a brief introduction, the text is
divided into three sections. The ®rst of these,
Experimental design, discusses types of variables,
experimental error, screening designs and three
component mixture designs. The following section,
Data analysis, comprises three chapters, dealing with
regression analysis, multiple objectives and problems
encountered with data, such as drift correction,
distribution of variance and outlier detection. In the
®nal part of the book, Experimental strategies, chapters
devoted to masterbatches, testing strategy and optimization strategy precede a concluding summary. The
clear and accessible text is complemented by a
software demo disk. This book may be of interest to
teachers or to scientists who seek an introductory
guide to this topic.
M D Purbrick
Modern techniques for polymer characterisation
Edited by RA Pethrick and JV Dawkins
John Wiley and Sons, Chichester, UK, 1999
pp xvii ‡ 392, price £140
ISBN 0-471-96097-7
A book bearing the title Modern techniques for polymer
characterization is bound to be inviting to all concerned
237
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