AbstractIt was observed in the gamma radiation‐induced graft polymerization of styrene to nylon that dilution of the styrene with methanol greatly accelerates the rate of styrene grafting. The compositions of the solutions absorbed by the nylon on equilibration with the various methanol—styrene solutions were determined. These results showed that the concentration of styrene available for the grafting reaction is much greater when the styrene—methanol solutions are employed than when undiluted styrene is employed. It was found that the values ofk p 2/ktfor these graft polymerizations are increased by a factor of 105compared to the corresponding value in homopolymerization. These increases in thek p 2/ktterm are ascribed to the greater viscosity of the medium in which the grafting reaction takes place and to the immobilization of the graft polymer chains by the Trommsdorff‐type effect of methanol. A discussion is presented of the applicability of steady‐state kinetics, as well as of the various competing reactions, in the gra