Pressure-induced phase separation PIPS

W. Zhuang and E. Kiran, Kinetics of pressure-induced phase separation (PIPS) from polymer solutions by time-resolved light scattering. Polyethylene + n-pentane, Polymer, 39,2903-2915 (1998). 

K. Liu and E. Kiran, Pressure-induced phase separation (PIPS) in polymer... 

Spinodal decomposition is of fundamental importance in processes involving phase separation of polymers in near- and supercritical fluids [145]. Pressure-induced phase separation (PIPS) has recently been used [4], with a novel experimental apparatus [146] that permits the imposition of rapid and controlled multiple pressure quenches, to study spinodal decomposition of near- and off-critical mixtures of a polymer and a compressed solvent following deep quenches into the unstable region. Spinodal decomposition is also important in SAS, in situations where the mass transfer pathway leads to penetration into the unstable region [76,147,148]. It can also be important in RESS involving polymeric solutes [35]. Experimental aspects of spinodal decomposition and the kinetics of phase separation in polymer solutions in near-critical fluids are discussed in the chapter by E. Kiran in this volume. 

Liu, K. and Kiran, E. (1999) Kinetics of pressure-induced phase separation (PIPS) in solutions of polydimethylsiloxane in supercritical carbon dioxide Crossover from nucleation and growth to spinodal decomposition. J. Supercrit. Fluids, 16, 59-79. 

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