Micro-phase separation

Fraai]e J G E M 1993 Dynamic density functional theory for micro-phase separation kinetics of block copolymer melts J. Chem. Phys. 99 9202... 

Suzuki, A. and Wrasa, O. An Approach to Artificai Muscle by Polymer Gels due to Micro-Phase Separation. Vol. 110, pp. 241 -262. 

Note 2 Ionic groups are usually present in sufficient amounts (typically less than 10 % of constitutional units) to cause micro-phase separation of ionic domains Ifom the continuous polymer phase. The ionic domains act as physical crosslinks. 

Artificial Muscle Using Polymer Gels Formed by Micro-Phase Separation... 

Furthermore the processes of physical gelation may be due to such a phase change across spinodal lines since micro-phase separation may induce the formation of a porous structure which could have high chemo-mechanical response. 

Poly(vinyl methyl ether), PVME, is a thermo-sensitive polymer. The aqueous solution has a Lower Critical Solution Temperature (LCST) of 37 °C. Therefore, PVME is soluble in water below its LCST, but insoluble above its LCST. When an aqueous solution of PVME is irradiated with y-rays the solution becomes PVME hydrogel [18, 19]. The gel shows thermo-sensitivity similar to the solution, and swells below 37 °C and shrinks above this temperature. It is important to form a fine porous gel structure to obtain quick response gels. There are two methods for the purpose. One is a method using micro-phase separation by heating. The other is a method using micro-phase separation by blending of polymer solutions. 

Porous PVME Gel Produced by Micro-Phase Separation Brought about by Heating... 

Fig. 13. Micro-phase separation of PVME aqueous solution by heating...

Method of Micro-Phase Separation by Blending Polymer Solutions... 

---