English Abstract
Polymer Blends: Principles and Applications
Part 2. Spinodal Decomposition and its Application

Takashi INOUE
Department of Polymer Science and Engineering, Yamagata University
Nippon Gomu Kyokaishi,(2005),78(9),345-350 General Review in Japanese

The principle of the spinodal decomposition (SD) is described in connection with the phase diagram of polymer-polymer mixture. Characteristic features of the structures developed via SD are the periodicity and the dual connectivity of decomposed-phases. The unique structure leads to high performance of the materials. In polymer systems, SD can be induced by: (i) simple temperature drop (or jump) from 1-phase region to 2-phase region in the phase diagram and the isothermal annealing, (ii) the chemical reactions,
such as polymerization and cure reaction, which cause the increase in molecular weight of the component, (iii) change in shear rate during melt-processing, such as extrusion and injection molding, (iv) solution casting of polymer blend (solvent evaporation), and (v) coagulation of polymer solution in non-solvent. Various examples of materials design by SD are shown.

Spinodal decomposition, Shear-induced homogenization, Reaction-induced phase decomposition, Solution casting, Coagulation, Bicontinuous structure