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This book provides an important structural analysis of polymer
solutions and melts, using fractal analysis. The book covers the
theoretical fundamentals of macromolecules fractal analysis. It
then goes on to discuss the fractal physics of polymer solutions
and the fractal physics of melts. The intended audience of the book
includes specialists in chemistry and physics of polymer synthesis
and those in the field of polymers and polymer composites
processing.
Using fractal analysis, irreversible aggregation models,
synergetics, and percolation theory, this book describes the main
reactions of high-molecular substances. It is the first to give the
structural and physical grounds of polymers synthesis and curing
based on fractal analysis. It provides a single equation for
describing the relationship between the reaction rate constants and
the equilibrium constants with the nature of the medium.
This new book explores the consideration of relationships that
connect the structural and basic mechanical properties of polymeric
mediums within the frameworks of fractal analysis with cluster
model representations attraction. Incidentally, the choice of any
structural model of medium or their combinations is defined by
expediency and further usage convenience only. This book presents
leading-edge research in this rapidly changing and evolving field.
The book presents descriptions of the main reactions of
high-molecular substances within the frameworks of fractal analysis
and irreversible aggregation models. Synergetics and percolation
theory were also used. In spite of the enormous number of papers
dealing with the influence of the medium on the rate of chemical
reactions (including synthesis of polymers), no strict quantitative
theory capable of "universal" application has been put forward up
until now. It is now possible to describe the relationship between
the reaction rate constants and the equilibrium constants with the
nature of the medium in which the reactions take place by means of
a single equation. This important book for the first time gives
structural and physical grounds of polymers synthesis and curing,
and the fractal analysis is used for this purpose. This new book: *
Highlights some important areas of current interest in polymer
products and chemical processes * Focuses on topics with more
advanced methods * Emphasizes precise mathematical development and
actual experimental details * Analyzes theories to formulate and
prove the physicochemical principles * Provides an up-to-date and
thorough exposition of the present state of the art of complex
polymeric materials
This text provides an important structural analysis of polymer
solutions and melts, using fractal analysis. The book covers the
theoretical fundamentals of macromolecules fractal analysis. It
then goes on to discuss the fractal physics of polymer solutions
and the fractal physics of melts. The intended audience of the book
includes specialists in chemistry and physics of polymer synthesis
and those in the field of polymers and polymer composites
processing.
This new book explores the consideration of relationships that
connect the structural and basic mechanical properties of polymeric
mediums within the frameworks of fractal analysis with cluster
model representations attraction. Incidentally, the choice of any
structural model of medium or their combinations is defined by
expediency and further usage convenience only. This book presents
leading-edge research in this rapidly changing and evolving field.
The book presents descriptions of the main reactions of
high-molecular substances within the frameworks of fractal analysis
and irreversible aggregation models. Synergetics and percolation
theory were also used. In spite of the enormous number of papers
dealing with the influence of the medium on the rate of chemical
reactions (including synthesis of polymers), no strict quantitative
theory capable of "universal" application has been put forward up
until now. It is now possible to describe the relationship between
the reaction rate constants and the equilibrium constants with the
nature of the medium in which the reactions take place by means of
a single equation. This important book for the first time gives
structural and physical grounds of polymers synthesis and curing,
and the fractal analysis is used for this purpose. This new book: *
Highlights some important areas of current interest in polymer
products and chemical processes * Focuses on topics with more
advanced methods * Emphasizes precise mathematical development and
actual experimental details * Analyzes theories to formulate and
prove the physicochemical principles * Provides an up-to-date and
thorough exposition of the present state of the art of complex
polymeric materials
Using fractal analysis, irreversible aggregation models,
synergetics, and percolation theory, this book describes the main
reactions of high-molecular substances. It is the first to give the
structural and physical grounds of polymers synthesis and curing
based on fractal analysis. It provides a single equation for
describing the relationship between the reaction rate constants and
the equilibrium constants with the nature of the medium.
Contents: Structure and Properties of Polymers in Terms of the
Fractal Approach; Fractal Kinetics of Radical Polymerisation of
Dimethyl Diallyl Ammonium Chloride; Thermodynamics of Polymer
Structure Formation in an Amorphous State; A Percolation Model of
Brittle-Ductile Transition for Polyethylene; The Dependence of
Diffusive Characteristics from the Size of Penetrant Molecules and
Structure for Polyenthylenes; Polymer Chain Flexibility and
Networks of Macromolecular Entanglements; Estimation of End-to-End
Distances for a Polycarbonate Chain within the Framework of the
Fractional Derivatives Theory; Molecular Weight Distribution of
Poly (Dimethyl Diallyl Ammonium Chloride): Analysis within the
Framework of Irreversible Aggregation Models; The Interrelation of
Fluctuation Free Volume and Structure for Polymer's Amorphous
State; Structural Aspects of Adhesion in Particulate-Filled Polymer
Composites; The Fractal Analysis of Curing Processes of Epoxy
Resins; Index.
Fractals & Local Order in Polymeric Materials
The interest in polymer composites study is due to an even greater
degree of their application. The filling by hard disperse
particulates or fibres gives to polymers a desirable properties
number: increases stiffness, reduces thermal expansion coefficient,
rises resistance to yield and fracture toughness and so on.
Difficulties in research of structure-properties relationships for
polymer composites are due to their structure complexity. So, on
the elasticity modulus value besides composition a polymer-filler
interaction influences. In other words, it is clear even
intuitively that for the complete description of such
structurally-complex objects as polymer composites it is necessary
to account for three groups of factors, namely, polymeric matrix
structure, filler structure and level of interaction between them.
Up to now the researches of such kind were carried out within the
frameworks of continuous mechanics and thermodynamic conceptions.
However, these conceptions application does not allow to describe
satisfactorily and all the more to predict such materials
properties. As a matter of fact, an experimental data set dictates
the choice of either structure physical model for macroscopic
properties description.
Nanochemistry is a science connected with obtaining and studying of
physical-chemical properties of particles having sizes on the
nanometer scale. This book addresses polymer synthesis which,
according to Melikhov's classification, is automatically part of
nanochemistry. This is determined as far as polymeric
macromolecules (more precisely macromolecular coils) belong to
nanoparticles and polymeric sols and gels - to nanosystems.
Catalysis on nanoparticles is one of the most important sections of
nanochemistry. The majority of catalytic systems are nanosystems.
At heterogeneous catalysis the active substance is tried to deposit
on carrier in nanoparticles form in order to increase their
specific surface. At homogeneous catalysis active substance
molecules have often in themselves nanometer sizes. The most
favorable conditions for homogeneous catalysis are created when
reagent molecules are adsorbed rapidly by nanoparticles and are
desorbed slowly but have high surface mobility and, consequently,
high reaction rate on the surface and at the reaction molecules of
such structure are formed at which desorption rate is increased
sharply. If these conditions are realised in nanosystem with larger
probability than in macrosystem, then nanocatalyst has the raising
activity that was observed for many systems.
Theoretical & Practical Guide to Organic Physical Chemistry
This book examines polymer nanocomposites filled by inorganic
nanofillers. Polymers are considered as nanocomposite matrix only,
possessing, as a rule, an invariable structure. In many respects
this situation is explained by the absence of a quantitative
structural model of polymers amorphous state. This problem becomes
particularly important because all structural elements of polymers
have sizes of nanometer scale. The development of notions about
polymers amorphous state structure within the frameworks of the
cluster model of this structure allows to represent amorphous
polymer as a quasitwophase system.
The interest in polymer composites research is due to their
enlarged application. Filling with hard particles gives to polymers
a number of desirable properties: increases hardness, decreases
heat expansion coefficient, improves resistance to creep and
fracture toughness. Difficulties in structure-properties
relationships researching for polymer composites are due to their
structure complexity. Till now, composites studies were conducted
within the frameworks of continuum mechanics and thermodynamic
conceptions. However, these conceptions applications does not allow
satisfactory descriptions nor predictions of such materials
properties. As a matter of fact, an experimental data set dictates
one or another physical model of structure choice for composites
macroscopic properties description.
Fractal analysis gives just general mathematical description of
polymers, i.e. it does not identify structural units (elements),
from which any real polymer is formed. Physical description of
thermodynamically non-equilibrium polymer structure in the
framework of the local order ideas gives the cluster model of the
polymer amorphous state structure that quantitatively identify its
elements. Since these models consider the polymer structure
somewhat from two sides, they are excellent completing one another.
It is common knowledge that structures displaying fractal behaviour
on small length scale and being homogeneous on large length scale
are named homogeneous fractals. These fractals are percolation
clusters at the percolation threshold. As shown below, the cluster
structure represents the percolation system and, due to the
above-said, the homogeneous fractal. To put it differently, the
presence of the local order in the condensed phase of polymers
determines fractality of their structures.
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