THERMAL STUDIES OF BLENDS OF POLY(PHENYLENE SULFIDE) (PPS) WITH POLY(PHENYLENE SULFIDE SULFONE) (PPSS) AND WITH POLY(PHENYLENE SULFIDE ETHER) (PPSE)

The miscibilities of poly(phenylene sulfide/poly(phenylene sulfide sul fone) (PPS/PPSS) and poly(phenylene sulfide/poly(phenylene sulfide eth er) (PPS/PPSE) blends were investigated in terms of shifts of glass tr ansition temperatures T-g of pure PPS, PPSS, and PPSE. The crystalliza tion kinetics of PPS/PPSS blends was also studied as a function of mol ar composition. The PPS/PPSS and PPS/PPSE blends are respectively part ially and fully miscible. PPSE shows a plasticizing effect on PPS as d oes PPS on PPSS, which necessarily improves the processibility in the respective systems. We can control T-g and melting temperature T-m of PPS by varying amounts of PPSE in blends. The melt crystallization tem perature T-mc of PPS/PPSE blends was higher than that of the PPSE homo polymer. Therefore, these blends require shorter cycle times in proces sing than pure PPSE. The overall rate of crystallization for PPS/PPSS blends follows the Avrami equation with an exponent similar or equal t o 2. The maximal rate of crystallization for PPS/PPSS blends occurs at a temperature higher by 10 degrees C than that for PPS, while the cry stallization half time t(1/2) is 4 times shorter. In the cold crystall ization range, crystal growth rates increase and Avrami exponents decr ease significantly as the temperature increases.