EFFECT OF GAMMA-IRRADIATION ON ELECTRICAL-CONDUCTIVITY OF METAL-CHLORIDE-TREATED POLYACRYLAMIDE

The electrical conductivity of polyacrylamide (PAAm) before and after treatment with low concentrations of ZnCl2, NiCl2, and CoCl2 was determined at different temperatures. The effects of gamma-irradiation on the electrical conductivity and activation energy of the original and the metal-chloride-treated specimens were investigated. The experimentally obtained data revealed that the conduction in PAAm is ionic in nature. The treatment of the polymer with 2% or 4% (w/w) of ZnCl2, NiCl2, or CoCl2, as determined from its weight, either increases or decreases its conductivity according to the nature of the metal ions, concentration of metal chloride, ratio of KOH/metal chloride, and temperature and cycle of measurement. The exposure of PAAm to 2 to 10 Mrad of gamma-radiation produces no significant changes in its conductivity. On the other hand, the exposure of the PAAm pretreated with a metal chloride produces considerable changes in its conductivity. Also, the gamma-irradiation of PAAm increases its activation energy. The extent of the gamma-induced changes in activation energy was influenced by the pretreatment of PAAm with metal chlorides.