Morphological studies of late‐stage spinodal decomposition in polystyrene–cyclohexanol system

Abstract

AbstractWe studied the late‐stage spinodal decomposition of the polystyrene–cyclohexanol system in relation to membrane formation. Phase separation was effected by the removal of thermal energy from the homogeneous polymer solution. The ultimate morphology of the phase‐separated systems has been studied using electron microscopy and has been found to be strongly affected by the quenching time. A shift from a highly interconnected open‐cell structure to a closed‐cell structure has been observed, indicating the transition of the spinodal decomposition from early to late stages. The cell growth in the late stage has been quantitatively analyzed and a power‐law relationship between the cell size and quenching time has been found. The resulting exponent of 0.61 is consistent with literature values from light‐scattering measurements, as well as from theoretical derivations. © 1995 John Wiley & Sons, Inc.