It was discovered that a novel blend of two super-engineering plastics, poly(p-phenylene sulfide) (PPS) and poly(phenylsulfone) (PPSU), has partial miscibility. The partial miscibility and the segmental mobility of PPSU at ∼–100 °C most likely contribute to remedy brittleness of PPS effectively. SAXS measurements revealed that segregation of PPSU chains during melt crystallization of PPS results in intrusion of PPSU chains into the amorphous region between PPS lamellae. TGA measurements under a nitrogen atmosphere demonstrated that the thermal stability of PPS blends is significantly improved upon the addition of PPSU.
