Abstract: | The radiation-induced graft copolymerization of vinyl acetate (VAc) onto ethylene-copropylene rubber (EPR) has been studied in methanol with radiation of cobalt-60. The effects of irradiation dose, dose rate, concentration of monomer, Cu++ concentration, and temperature on the degree of grafting were investigated. The dependence of the initial grafting rate on dose rate, monome, and Cu++ concentration were found to be 1.0, 1.95, and 0.5 order, respectively. The apparent activation energy was calculated to be 49 kJ/mol. Mechanical properties of the grafted polymer were investigated as a function of the grafting percentage. The tensile strength increases and elongation of break decreases with the increase of the degree of grafting in the region of low grafting percentage (≅ 10%). © 1996 John Wiley & Sons, Inc. |