Chapter 11
Interplay Between Phase Separation and
Polymer Crystallization
11.1 Complexity of Polymer Phase Transitions
Soft matter is often called complex fluids. Polymers are one type of complex fluids.
Their complex behaviors in phase transitions appear in the spatial and temporal
evolution of multi-phase structures. Often, multiple phase transitions coexist and
interplay with each other, either in cooperation or in competition. Therefore, the
subject of complex systems may be helpful in our elucidation of the complex
formation mechanism of multi-phase structures.
The emergentism suggests that a complex system is featured as an integration of
its constituents becoming larger than their simple addition, while the traditional
reductionism suggests to splitting it into several simple parts for a separate analysis.
According to the emergentism, the complex sources from “1þ 1 >2”. Taking the
interplay between phase separation and polymer crystallization for an example, we
look at the emergent properties different from individual phase transitions. These
properties may reveal the complex formation mechanism of multi-phase structures.
Multi-component polymers range from solutions and blends to copolymers. Both
the phase separation and the crystallization processes hold a wide time window, and
their thermodynamic conditions are easy to achieve. These attributes make the
multi-component polymer system a good example in the study of the complex
formation mechanism of multi-phase structures.
The interplay of polymer phase transitions has been extensively studied in
solutions, dated back to Richards in 1946 (Richards 1946 ). Flory’s classical book
in 1953 introduced the complete set of phase diagrams (Flory 1953 ). Recently,
Cheng comprehensively reviewed the experimental progress on the interplay of
polymer phase transitions (Cheng 2008 ). Keller emphasized in a review paper that,
in the preparation of the thermoreversible gel, crystallization can freeze the gel
structure generated by the prior continuous phase separation (Keller 1995 ).
A practical example of such interplay of phase transitions is in the production of
W. Hu,Polymer Physics, DOI 10.1007/978-3-7091-0670-9_11,
#Springer-Verlag Wien 2013
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