Effect of different forms of ionizing radiations on polytrifluorochloroethylene and polyvinyl chloride

Abstract

The effect of ⁶⁰Co γ-radiation and α-particles with an energy 22 MeV on polytrifluorochloroethylene and polyvinyl chloride has been studied at the boiling point of nitrogen. It is shown that on irradiation of the polymers there is stabilization of some paramagnetic centres the chemical nature of which is independent of the type of radiation. With rise in the linear energy transfer of the radiation the radiation yield of the paramagnetic centres, which for polytrifluorochloroethylene is 0.3 and 0.2 and for PVC 2.0 and 1.3 1/100 eV respectively on exposure to ⁶⁰Co γ-radiation and α-particles, diminishes. The temperature intervals are defined at which there is intense decay of the paramagnetic centres. The rate of degradation of polytrifluorochloroethylene and the rate of crosslinking of PVC do not depend on the changes in the linear energy transfer of radiation. The results may be used to predict the radiation tolerance of polymers and determine the optimum conditions for modifying their properties with use of different forms of radiation.