γ‐ray and ultraviolet graft copolymerization of maleimide by vapor‐phase method

Abstract

Abstract Graft copolymerization of maleimide onto ethyl cellulose and polyethylene films by using its sublimation vapor was carried out under γ‐ or ultraviolet irradiation. When polyethylene film was used as a backbone polymer the grafting reaction proceeded without a perceptible sorption of monomer, while a considerable amount of monomer was captured into ethyl cellulose film and grafting of the sorbed monomer was observed. The monomer seemed to be monomolecularly dispersed in this film. The presence of air retarded the reaction. The grafted films were characterized by strong infrared absorption bands due to polymaleimide branching. The fractions assigned to the graft copolymer were isolated from the grafted films by selective elution. The grafted branches were supposed to be very short, judging from the polymaleimide contents of those fractions.