Abstract: Using H₂S, NaOH and p-C₆H₄Cl₂ as raw materials and proper Na₃PO₄ as an assistant in hex-amethylphosphoryltriamide(HPT), the crystal linear poly (p-phenylene sulfide) resins with high molecular weight (HMWPPS) was synthesized during 4～5 h under normal pressure.The properties of the polymer were determined, m. p. >290 ℃; decomposition temperature by heat>500 ℃; low shear viscosity at melting state: 3.0-68.0×10³ Pa (determined at 303 ℃). The product was used to do the melt spun test directly and the fiber of the HMWPPS was obtained. This method has following obvious advantages as the equipment is simple, operation is easy, reaction system has a higher activity, solvent is stable, product recovery ratio is high, cost is low and it is easy to put into large-scale production.

Key words: Poly(p-phenylene sulfide) with high molecular weight, Repeating units, Low shear viscosity at melting state, Hexamethylphosphoryltriamide