Gamma-rays irradiation effects on polysulfone at high temperature

The temperature dependence of the irradiation effects on polysulfone was studies by measuring the molecular weight, glass transition temperature, gel fraction and evolved gas. Polysulfone was irradiated with gamma-rays at room temperature, 100, 150, 180 and 210 degrees C. The change of molecular weight distribution and glass transition temperature showed occurrences of a main chain scission at room temperature and cross-linking at high temperature. The decrease of gel dose, the increases of gel fraction and total gas evolution with increasing temperature was observed. The evolution of CO, CO2 and SO2 gases increased at high temperature, while yield of evolved H-2 was independent of irradiation temperature. The probability of the cross-linking was clearly increased by irradiation at high temperature above 180 degrees C, though the chain scission was not changed very much. (C) 2007 Elsevier B.V. All rights reserved.