Polymer Physics

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invented in the study of natural polymers such as celluloses and natural rubbers.
The fast development of global science and technology in the middle of twentieth
century resulted in a broad application of these concepts in the research and
development of synthetic polymer materials. Entering twenty-first century,
materials sciences have been well established, while quantitative life sciences are
still developing fast. We speculate that polymer physics will continue to expand its
cutting-edge knowledge, by following the calls for advanced materials, new
energies and green environments of our society. It remains nourishing, and being
nourished by, the flourishing of life sciences. As already pointed out by Staudinger
in 1953 (Staudinger 1953 ), “In the light of this new knowledge of macromolecular
chemistry, the wonder of Life in its chemical aspect is revealed in the astounding
abundance and masterly macromolecular architecture of living matter.”


1.4 Focusing of this Book


Polymer physics covers a wide landscape of polymer structures and their physical
properties. The description of the relationships between structures and properties
evolves from the early-stage trial-and-error empirical equations to the currently
well-established statistical thermodynamic and kinetic theories.
Thomas Kuhn has pointed out in his well-known book “The Structure of Scientific
Revolutions” (Kuhn 1996 ) that, the scientific progress of each subject experiences
four phases: the pre-paradigm phase, the normal science, the anomaly and crisis, and
the revolutionary science. “Normal science means research firmly based upon one or
more past scientific achievements, achievements that some particular scientific com-
munity acknowledges for a time as supplying the foundation for its further
practice.”(P10) “These are the community’sparadigms, revealed in its textbooks,
lectures, and laboratory exercises. By studying them and by practicing with them, the
members of the corresponding community learn their trade.”(P43)
There are two statistical thermodynamic theories that can be regarded as the
basic theoretical paradigms in polymer physics. The first theory is the Gaussian
statistical treatment of ideal single-chain conformations, used to calculate the
conformational entropy. This theory allows us to apply the scaling analysis (as
well as the self-consistent-field theory) to treat more realistic single-chain confor-
mation and to describe chain dynamics based on Brownian motions. The first theory
and its extension cover the first half content of this book. The second theory is the
Flory-Huggins lattice statistical treatment of multi-chain conformations, used to
calculate the mixing entropy. This theory allows us to apply the mean-field treat-
ment to estimate the inter-chain attractions and then to understand the thermody-
namic processes of chain assembly, such as liquid-liquid phase separation and
polymer crystallization. The second theory and its extension cover the second
half content of this book. Both these theories are based on the assumption that
chain conformations can be modeled by the trajectories of random walks. In other
words, both theories rest on the framework of Brownian motion, which is the basic
dynamic feature for all types of soft matter particles.


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