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Nanotechnologies development in various directions of science and
engineering represents one of the most high-priority problems of
modern science. One of such directions is the development and
research of polymer nanocomposites with filler from nanoparticles
and nanotubes possessing the increased strength and
flame-resistance. In the last decade in the world literature a
large amount of works have appeared which are dedicated both to
technological and fundamental problems of polymer nanocomposites
creation. The main part of these works adduced studies of polymer
nanocomposites structure and properties, in which as filler
organoclays with particles size of nanometre scale (for example,
Na+-montmorillonite) were applied as a filler. Key studies in this
field mainly use various kinds of modifications of large
micromechanical models, created at one time for the description of
polymer composites properties in general. These modifications are
cumbersome enough, and mainly use complex computer technologies and
although with their help convincing enough results were obtained,
one should pay attention on their narrowness. In present quite many
classes of polymer nanocomposites are obtained, having different
reinforcement mechanisms, but the general ones in the sense, that
these mechanisms are realised at the expense of introduction in
polymer matrix particles of nanometre sizes. As it is known, the
main peculiarity of such particles is a sharply increased
polymer-filler contact area in comparison with usual fillers of
micron scale size, that gives maximum reinforcement effect at small
nanofiller contents. Hence it follows, that the main research
object in the given case should be interfacial phenomena on polymer
matrix-filler boundary, to which Academician Lipatov pointed as
long as 40 years ago. Another important postulate is the fractal
nature of nanoparticles structure, defining the mentioned above
interfacial interactions level. The two postulates mentioned would
be the main at the structure and properties of polymer
nanocomposites analysis in the present monograph. At the same time
the authors do not exlude the application of other model
representations, for example, of the mentioned above
micromechanical models.The purpose of the present monograph is the
research of structure-properties relationships, defining a polymer
nanocomposites reinforcement mechanism, for seven different classes
of these materials. For these tasks solution the modern physical
conceptions: synergetics of solid body, cluster model of polymers
amorphous state structure, percolation theory are used.
In the present monograph, theoretical structural analysis of the
main processes of gas transport in polymeric materials (diffusion,
solubility, permeability and selectivity) was offered. The
mentioned analysis uses fractal (multifractal) analysis and cluster
model of polymers amorphous state structure, based on the local
order notions, as a tool for polymeric materials structure
description. Besides, for the mentioned gas transport processes
description, such modern physical treatments as a multifractal
model of fluctuation free volume and the conception of anomalous
(strange) diffusion were used. Such approach allows the
quantitative description of gas transport processes and their
prediction as a function of testing temperature, degree of
crystallinity, cross-linking and grafting, and so on. Special
attention is given to gas transport processes in multicomponent
polymeric systems. A number of practical aspects of theoretical
structural analysis application was considered in cases of thermal
degradation, interfacial layers formation in polymer composites,
stability to cracking in active environments and chemical
reactions.
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