GAMMA-IRRADIATION OF POLY(PHENYLENE SULFIDE) - EFFECTS ON CRYSTALLIZATION BEHAVIOR

The irradiation of polymers can bring about significant changes in the polymer structure and ultimately in their performance. Poly(phenylene sulfide) (PPS) is an engineering polymer which is mostly used in appl ications where it is subjected to high-energy radiation. This paper re ports the results of gamma irradiation of PPS. The technique of differ ential scanning calorimetry was used to monitor the changes in the mel ting and crystallization parameters of irradiated PPS. The heat of fus ion was found to decrease upon irradiation, indicating a lower degree of crystallinity; however, a marginal increase was observed in the mel ting point. The nonisothermal crystallization of irradiated PPS indica ted reduced crystallizability. This contention is also supported by th e isothermal crystallization studies in which the crystallization rate for irradiated PPS was found to be decreased. The retardation in the crystallization of irradiated PPS has been attributed to the possible changes in the structure of the polymer.