Development of the Polyphenylene Sulfide Synthesis Technology

A procedure was developed for preparing polyphenylene sulfide with low melt viscosity by liquid-phase polycondensation at pH > 12 with stepwise heating from 160 to 220°С in the prepolycondensation step and from 230 to 260°С in the afterpolycondensation step. The polyphenylene sulfide melt flow index can be varied from 300 to 18 g/10 min by stepwise variation of the Na 2 S excess and temperature in the course of polyphenylene sulfide polycondensation. The optimum time of the polyphenylene sulfide synthesis was 16 h. The polyphenylene sulfide exhibits the physicomechanical properties similar to those of Ryton@ XE5500BL thermoplastic (Solvay) but is characterized by 50% lower water absorption.