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Polymer International
Book reviews
Polym Int 48:621±622 (1999)
in light of their enhanced properties which may reduce
the incidence of failure.
F Schué
Medical plastics – degradation resistance and
failure analysis
Edited by Robert C Portnoy
Plastics Design Library (A Division of William Andrew
Inc.) Norwich, New York, 1998
pp 215 price $160.00
ISBN 1-884207-60-X
This book depends upon the reader's appreciation of
an eclectic range of papers, uni®ed by the underlying
theme of improvement of the performance of medical
devices and packages by an understanding of their
many modes of failure. Both tutorial papers, reviewing
well established areas of technology, and research
accounts of the latest developments in technical areas
are included.
The ®rst paper reviews the use of polymers in
medical applications as illustrated by the design,
characterization and application of tyrosine-derived
polymers: degradable polymers derived from L-tyrosine are one of a novel class of polymers being
investigated as implantable, degradable materials for
medical applications.
The second paper describes how performance
characteristics of packaging materials are a critical
factor in the functioning of package seals, which must
be kept within speci®ed limits to achieve consistant
seal integrity.
There are several papers on analytical methods.
Some of these determine or predict the performance or
assure the quality of medical goods, focusing on the
role of modern analytical instrumentation used in
electron spectroscopy, microscopy, and organic
analysis of material surfaces and substrates
Other methods are used to study failed medical
components to elucidate the cause of failure. By
evaluating mechanical, chemical and physical properties before and after service, the examiner cannot only
quantify changes in properties but also determine the
cause of the change. The accumulated property data
are also useful for subsequent stress analysis or
modelling. Because sterilization methods are so severe
on many materials commonly used in medical
components, there is extensive coverage of this topic,
including papers on high energy, ethylene oxide, and
autoclave sterilization of propylene, polyethylene,
polycarbonate and polyvinyl chloride. The closely
related area of the resistance of device construction
materials to chemicals and other environmental
stresses such as low temperature is also covered in
several papers. Because error-free assembly of devices
is required for them to resist failure, this aspect is also
considered. Several novel materials are also discussed
‘Petro’ polymers vs ‘green’ polymers
Edited by LA Kleintjens
Hüthig and Wepf Verlag, Zug, 1997
pp 273 price, US$85.00
ISBN 3-85739-324-6
For thousands of years nature was the only source of
polymeric materials. Even now many natural polymer
products are still present on the market (eg wood, silk,
cotton, cellulose, natural rubber and varnish). We all
know the extensive list of synthetic polymers, for the
greater part based on fossil carbohydrates. The latest
developments and the `green character' of both these
types of polymer are discussed.
The development of biopolymers has been focused
mostly on the bulk plastic masket. The goal for most
companies has been to produce plastics which can be
used for short term applications, such as disposable
items (eg cutlery, coffee cups) and garbage bags, for
which the solid waste problem is most urgent.
However, there are several types of biopolymers which
appear to be most promising, including polysaccharides (as gelling and thickening agents) and bacterial
cellulose. For the latter, remarkable progress of ®bre
properties has been observed, compared with regenerated cellulosic ®laments.
Substituted starches have been synthesized to
establish the structural change, ie the necessary
amount and length of mobile chains which support a
molecule with high enough levels of internal degrees of
freedom. Esteri®cation and transesteri®cation with
hydroxy alkanoates, their polymers and lactones have
been used.
In the development of technical applications of
polymers from renewable resources, various biopolymers are being studied. Opportunities for the industrial proteins on the market are discussed, eg for use in
coatings, adhesives, surfactants and plastics. The use
of protein modi®cation for the improvement of
functional properties relevant for technical applications is addressed.
Some polymers are produced both by industry and
by nature (polyaminoacids, polyesters, casein) and the
production of synthetic polymers from `green monomers' (CO2, CH4, ethylene, etc) is shown to be well
within reach. Finally, the combination of products
from both areas may lead to attractive new materials
(composites and blends of synthetic and biopolymers,
chemically modi®ed green polymers, copolymers, and
# 1999 Society of Chemical Industry. Polym Int 0959±8103/99/$17.50
621
Book reviews
so on). The synergy of `petrobased' and `green'
polymer combinations is extensively discussed.
F Schué
exploitation of modi®ed polymers. The book is,
therefore of more interest to the practitioner in the
®eld rather than to someone wanting a general
introduction.
WA MacDonald
Polymer modification
Edited by Graham Swift, Charles E Carraher, Jr, and
Christopher N Bowman
Plenum Press, New York, 1997
pp viii‡212, price US$95.00
ISBN 0-306-45714-8
Polymer Modi®cation is not a reference text, as the title
might misleadingly suggest, but is a conference volume
containing papers presented at the symposium on
Polymer Modi®cation held at the ACS Meeting in
Florida in 1996. It covers the chemical modi®cation of
polymers in three parts. The ®rst part on surface
modi®cations covers imidization of PMMA via reactive
extrusion, photohydroperoxidation of unsaturated
elastomers, the synthesis of hydrophobe-modi®ed
water-soluble polymers using phase transfer catalysis,
and chemical modi®cation of poly(lactic acid)-based
products. The second part on reaction with vinyl
polymers, covers functionalization or chemical modi®cation of (i) polyole®ns, (ii) acrylamide polymers and
(iii) poly(vinylbenzyl chloride), the formation of
magnesium partially-stabilized zirconia ceramics,
grafting of vinyl monomers on to polystyrene copolymers, crosslinking by glutaraldehyde and substitution
reactions on poly(chlorotri¯uoroethylene). The ®nal
section, on inorganic-containing and shaped polymers, includes the synthesis of (i) tin ionomers based
on ethylene±acrylic acid copolymers, (ii) titanocene
polyethers, and (iii)styrene- and siloxane-based silanol
polymers, the synthesis and ion-coupling reactions of
telechelic poly(dimethylsiloxane), the modelling of
poly(acrylic acid) and its salts, and modelling of boron
speciation in solution with a reactive dendrimeric
polymer.
The book is wide ranging in the subject area
covered, and provides a useful overview of current
research themes in chemical modi®cation of polymers.
The papers describe current research: as such the book
does not provide a systematic reference summary of
the general subject area and provides little information
on the properties of the modi®ed polymers and the
622
Polymers and copolymers of higher a-olefins
Edited by BA Krentsel, YV Kissin, VI Kleiner and LL
Stotskaya
Carl Hanser Verlag, Munchen 1997
pp vii‡374, price DM 198, US$147.50, UK£83,
ÖS1445
ISBN 3-446-17593-8
The book starts with an introductory chapter on the
principles of ole®n polymerization and then covers the
higher a-ole®n polymers and copolymers in turn,
1-butene, higher linear a-ole®ns, 4-methyl-1-pentene,
a-ole®ns with branched alkyl groups, vinylcyclohexanes and ®nally copolymers of ethylene and higher
a-ole®ns. It is `dedicated' to cover all aspects of these
polymers and copolymers including commercial
manufacture, physical properties, resin processing
and applications. Chemists interested solely in polymerization catalysts, reaction mechanisms, structure,
chemical and physicochemical properties, will ®nd it
interesting and informative. Any claim that the book
covers, in the same expertise and detail, all aspects of
commercial production, properties, processing and
applications cannot be upheld. Particular irritations
are the lack of standardized test methods in the
physical property tables and the incorrect use of `melt
index' (when it should be mass or volume melt ¯ow
rate). The chapter on copolymers of ethylene and
higher a-ole®ns is particularly disappointing in this
respect, as these copolymers contribute more than
95% of present commercial production. Most of the
information in the chapter on processing and applications deals with the newer LLDPE polymers, and this
tends to give the reader a rather unbalanced view of
ethylene copolymers as a whole. This weaker treatment contrasts starkly with the ®nal chapter, which is a
review of the thermodynamics of higher a-ole®ns and
their polymerization reactions.
WJ Allwood
Polym Int 48:621±622 (1999)
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