| Abstract: | The effects of kind of acid and irradiation of ultraviolet light on the graft copolymerization of methyl methacrylate onto cellulose with adsorbed ceric ion were investigated. Irrespective of ultraviolet light irradiation, the amount of reduced ceric ion in the reaction systems was increased in the order HCl > HClO4 > HNO3 > H2SO4, and the number of grafts formed was increased in the order HClO4 > HNO3 > HCl > H2SO4. Thus, it was definitely observed that the graft copolymerization is affected by the kind of acid. Ultraviolet light remarkably accelerated the reduction of ceric ion adsorbed on cellulose in the various acid mediums, but decreased the efficiency of graft formation. The most favorable results for the formation of grafts were obtained in the system in which HClO4 and ultraviolet irradiation was employed. A combination of H2SO4 and ultraviolet irradiation resulted in the lowest per cent grafting and average molecular weight of grafts. It was found that H2SO4 characteristically dissolves out ceric ion adsorbed into an aqueous solution and accelerates the formation of homopolymer. |
