Porous polyphenylene sulfide membranes were prepared as new solvent-resistant membranes by the thermally induced phase-separation (TIPS) method. Porous structures were either formed by solid-liquid phase separation (polymer crystallization) or liquid-liquid phase separation. The effects of solvents, cooling rates, and polymer concentrations on the porous structures were investigated. Various characteristics of pore structure can be obtained with suitable diluents and cooling rates using the TIPS method. (c) 2006 Wiley Periodicals, Inc.