Poly(phenylene sulfide). Part I. Preparation and properties

A review with 24 references covering the methods of preparation and crystallization and recrystallization of PPS. The available data allow to conclude that PPS has been commercially produced via homopolycondensation of alkali metal halophenolates or heteropolycondensation of 4,4'-dibromobenzene with anhydrous sodium sulfide in polar organic solvents used as reaction media. PPS is an engineering polymer endowed with excellent thermal resistance (long-time operation at 240 degrees C); however, PPS is expensive. When heated to temperatures exceeding 300 degrees C, PPS undergoes cyclization, branching and crosslinking processes to yield, occasionally, quasi-ladder linear structures. PPS is also well resistant to chemicals and solvents; but not to UV radiation. At temperatures lower than 175 degrees C, PPS is insoluble in any solvent. The acute condensation conditions, corrosion of equipment, and the toxicity of waste waters and off-gases render production of PPS very difficult.