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Books > Science & Mathematics > Chemistry > Organic chemistry > Polymer chemistry
Among various branches of polymer physics an important position is
occupied by that vast area, which deals with the thermal behav ior
and thermal properties of polymers and which is normally called the
thermal physics of polymers. Historically it began when the un
usual thermo-mechanical behavior of natural rubber under stretch
ing, which had been discovered by Gough at the very beginning of
the last century, was studied 50 years later experimentally by
Joule and theoretically by Lord Kelvin. This made it possible even
at that time to distinguish polymers from other subjects of
physical investigations. These investigation laid down the basic
principles of solving the key problem of polymer physics -
rubberlike elasticity - which was solved in the middle of our
century by means of the statistical thermodynamics applied to chain
molecules. At approx imately the same time it was demonstrated, by
using the methods of solid state physics, that the low temperature
dependence of heat capacity and thermal expansivity of linear
polymers should fol low dependencies different from that
characteristic of nonpolymeric solids. Finally, new ideas about the
structure and morphology of polymers arised at the end of the 1950s
stimulated the development of new thermal methods (differential
scanning calorimetry, defor mation calorimetry), which have become
very powerful instruments for studying the nature of various states
of polymers and the struc tural heterogeneity."
The U. S. -Japan Polymer Symposium-1980 at the Tenth Biennial
Symposium was held during the period November 21-26, 1980 at the
Palm Springs Spa Hotel in Palm Springs, California. This Symposium
was jointly sponsored by the Division of Polymer Chemistry of the
American Chemical Society and the Society of Polymer Science,
Japan. It is hoped that this joint symposium between the Japanese
and Americans will become a regular event with the next sym- posium
to be held in Japan. Although there have been several small joint
meetings between the Japanese and American poly- mer scientists
sponsored by the governments of the two countries with restricted
topics and restricted attendance held in both countries, this
symposium represented the first large meeting held in cooperation
between the two societies with broad spectrum of topics and
unrestricted attendance. In planning the program the Co-Chairmen,
William J. Bailey and Teiji Tsuruta, tried to make the program as
balanced as possible, both with regards to subject matter and
representation from the two countries. They selected 24 invited
lecturers, twelve from Japan as follows: Kohei Sanui, Sophia
University Takeo Shimidzu, Kyoto University Shohei Inoue,
University of Tokyo Itaru Mita, University of Tokyo Yuka Yamashita,
Nagoya University Yozo Chatani, Osaka University Itsuo Aishima,
Asahi Chemical Industry Co. , Ltd. Toshio Hayashi, Kyoto University
Takuhei Nose, Tokyo Institute of Technology Tisato Kajiyama, Kyushu
University Shigeo Tazuke, Tokyo Institute of Technology Naohiro
Murayama, Kureha Chemical Industry CO. ,Ltd.
QCM-D Studies on Polymer Behavior at Interfaces reviews the
applications of quartz crystal microbalance with dissipation
(QCM-D) in polymer research, including the conformational change of
grafted polymer chains, the grafting kinetics of polymer chains,
the growth mechanism of polyelectrolyte multilayers, and the
interactions between polymers and phospholipid membranes. It
focuses on how QCM-D can be applied to the study of polymer
behavior at various solid-liquid interfaces. Moreover, it clearly
reveals the physical significance of the changes in frequency and
dissipation associated with the different polymer behaviors at the
interfaces.
-Effects of Electric Fields on Block Copolymer Nanostructures By H.
G. Schoberth, V. Olszowka, K. Schmidt, and A. Boeker -Nanopattern
Evolution in Block Copolymer Films: Experiment, Simulations and
Challenges By L. Tsarkova, G.J. Agur Sevink, and G. Krausch
-Controlled Wrinkling as a Novel Method for the Fabrication of
Patterned Surfaces By A. Schweikart, A. Horn, A. Boeker, and A.
Fery -Layered Systems Under Shear Flow By D. Svensek and H. R.
Brand -Thermal Diffusion in Polymer Blends: Criticality and Pattern
Formation By W. Koehler, A. Krekhov, and W. Zimmermann -Foaming of
Microstructured and Nanostructured Polymer Blends By H.
Ruckdaschel, P. Gutmann, V. Altstadt, H. Schmalz, and A.H.E. Muller
Catalysis involves just about every field of scientific study. This
means that a multidisciplinary approach is needed in catalytic
studies. Catalysis involves breaking and forming new bonds and this
requires an under standing of either adsorption by bonding to an
extended structures or bonding in a coordination sphere. Any
understanding of catalytic action must necessarily involve an
understanding of this bonding. Even 200 years ago scientists were
aware that a properly treated mate rial, such as charcoal, could
adsorb an enormous quantity of gas. In 1812, de Sassasure (English
translation, Annal Philosphy, 6, 241 (1815 pro posed that the
ability of a material to increase the rate of chemical reac tion
was due to adsorption of the material in the fine structure of the
solid so that the concentrations of the reactants were
significantly increased, and this increase in concentration led to
an increase in reaction rate. During the 1800s, little advance was
made in the understanding of adsorp tion."
At the beginning of the twentieth century, engineers and
technologists would have recognized the importance of adhesion in
two main aspects: First, in the display of friction between
surfaces - at the time a topic of growing importance to engineers;
the second in crafts requiring the joining of materials -
principally wood-to form engineering structures. While physical
scientists would have admitted the adhesive properties of glues,
gels, and certain pastes, they regarded them as materials of
uncertain formulation, too impure to be amenable to precise
experiment. Biological scientists were aware also of adhesive
phenomena, but the science was supported by documentation rather
than understanding. By the end of the century, adhesion and
adhesives were playing a crucial and deliberate role in the
formulation of materials, in the design and manufacture of
engineering structures without weakening rivets or pins, and in the
use of thin sections and intricate shapes. Miniaturization down to
the micro- and now to the nano-level of mechanical, electrical,
electronic, and optical devices relied heavily on the understanding
and the technology of adhesion. For most of the century, physical
scientists were aware that the states of matter, whether gas,
liquid, or solid, were determined by the competition between
thermal energy and int- molecular binding forces. Then the solid
state had to be differentiated into crystals, amorphous glasses,
metals, etc. , so the importance of the molecular attractions in
determining stiffness and strength became clearer.
This and its companion Volume 2 chronicle the proceedings of the
First Technical Conference on Polyimides: Synthesis, Char
acterization and Applications held under the auspices of the Mid
Hudson Section of the Society of Plastics Engineers at Ellenville,
New York, November 10-12, 1982. In the last decade or so there has
been an accelerated interest in the use of polyimides for a variety
of applications in a number of widely differing technologies. The
applications of polyimides range from aerospace to microelectronics
to medical field, and this is attributed to the fact that
polyimides offer certain desirable traits, inter alia, high
temperature stability. Polyimides are used as organic insulators,
as adhesives, as coat ings, in composites, just to name a few of
their uses. Even a casual search of the literature will underscore
the importance of this class of materials and the high tempo of
R&D activity taking place in the area of polyimides. So it was
deemed that a conference on polyimides was both timely and needed.
This conference was designed to provide a forum for discussion of
various ramifications of polyimides, to bring together scientists
and technologists interested in all aspects of polyimides and thus
to provide an opportunity for cross-pollination of ideas, and to
highlight areas which needed further and intensi fied R&D
efforts. If the comments from the attendees are a baro meter of the
success of a conference, then this event was highly successful and
fulfilled amply its stated objectives.
Pt. A: NMR and other Spectroscopic Methods. Pt. B: Mechanical
Methods
This book arose from a symposium titled 'Transition Metal Carbides
and Nitrides: Preparation, Properties, and Reactivity' organized by
Jae Sung Lee, Masatoshi Nagai and myself. The symposium was part of
the 1995 Congress of Pacific Rim Chemical Societies, held in
Honolulu, Hawaii between December 17-22, 1995. The meeting was the
first major conference to exclusively address the theme of metal
carbides and nitrides, and brought together many of the major
researchers in the field. Over 50 scientists and engineers reported
their latest findings in five sessions of presentations and
discussions. The book closely follows the topics covered in the
conference: Theory of bonding Structure and composition Catalytic
properties Physical properties New methods of preparation
Spectroscopy and microscopy The book is unique in its coverage. It
provides a general introduction to the properties and nature of the
materials, but also covers their latest applications in a wide
variety of fields. It should thus be of interest to both experts
and nonexperts in the fields of material science, solid-state
chemistry, physics, ceramics engineering, and catalysis. The first
chapter gives an overview, and many of the chapters provide
summaries of advanced topics. All contributions were peer-reviewed.
Over the past 40 years, Rotational Isomeric State (RIS) models for
hundreds of polymer structures have been developed. The RIS
approach is now available in several software packages. The user is
often faced with the time-consuming task of finding appropriate RIS
parameters from the literature. This book aims at easing this step
by providing a comprehensive overview of the models available. It
reviews the literature from the first applications of RIS models to
the end of 1994, comprises synthetic as well as naturally orccuring
macromolecules, and tabulates all the pertinent features of
published models. It will help readers, even when not very familiar
with the method, to take advantage of this computationally
efficient way of assessing the conformational properties of
macromolecular systems.
This book reviews recent advances in polymer swelling resulting
from the use of novel microporous composite films. It offers a new
approach to understanding sorption processes in polymer-liquid
systems based on the molecular structures of the sorbed molecules
and the repeat unit of the sorbent polymer. It is shown how the
adsorption parameters obtained in these studies relate meaningfully
with the Flory-Huggins interaction parameters. This implies that
these adsorption parameters have relevance not only for swelling
and drying of polymers, but also for other phenomena in which
molecular sorption plays an important role, such as in
chromatography and in membrane permeation.
Most of the untreated surfaces of polymers used in industry are not
hydrophilic but hydrophobic. It is, therefore, difficult to bond
these nonpolar polymer sur faces directly to other substances like
adhesives, printing inks, and paints because they generally consist
of polar compounds. On the other hand, polymer surfaces generally
adsorb proteins when brought into direct contact with a bio logical
system, resulting in cell attachment or platelet aggregation. The
protein adsorption and attachment of biological components trigger
a subsequent series of mostly adverse biological reactions toward
the polymeric materials. Therefore, the technologies for surface
modification of polymers or regulation of the polymer surface
interaction with other substances have been of prime importance in
polymer applications from the advent of polymer industries. Some of
the technologies have been directed to introduction of new function
alities onto polymer surfaces. The new functionalities introduced
include improved surface hydrophilicity, hydrophobicity, bio
compatibility, conductivi ty, anti-fogging, anti-fouling, grazing,
surface hardness, surface roughness, adhesion, lubrication, and
antistatic property. Theoretically, there is a large dif ference in
properties between the surface and the bulk of a material and only
the outermost surface is enough to be taken into consideration when
the sur face properties are concerned. However, this is not the
case for polymer surfaces, as the physical structure of the
outermost polymer surface is generally not fixed but continuously
changing with time due to the microscopic Brownian motion of
polymer segments."
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