CELLULOSE GRAFT COPOLYMERS .I. GRAFT COPOLYMERIZATION OF ETHYL ACRYLATE WITH GAMMA-IRRADIATED CELLULOSE FROM METHANOL-WATER SYSTEMS

Ethyl acrylate was graft‐copolymerized with γ‐irradiated, purified cotton cellulose from methanol–water systems. The accessibility of the free radicals in the irradiated cellulose to water, methanol, ethyl acrylate, and methanol–water solutions was determined by electron spin resonance spectroscopy. The maximum scavenging of the radicals was recorded with the irradiated cellulose was immersed in methanol–water solution which had a composition of 50/50 vol‐%. When ethyl acrylate was added to methanol–water solution (50/50 vol‐%), maximum grafting on the irradiated cellulose occurred at a concentration of ethyl acrylate of about 20 vol‐%. As the concentration of ethyl acrylate was decreased, maximum grafting occurred in solutions containing less than 50 vol‐% methanol. It was also noted that maximum grafting of ethyl acrylate in methanol–water solutions to irradiated cellulose occurred at boundry conditions, that is, conditions where the ternary mixture was still one phase, slightly different from compositions which caused the mixture to separate into two phases. From methanol solution, maximum grafting occurred at a concentration of ethyl acrylate of 80 vol‐%. The extent of grafting from methanol was less that obtained from methanol–water solutions at lower concentrations of ethyl acrylate. The accelerative effects of water was considered to be due to the Trommsdorff effect. Copyright © 1969 John Wiley & Sons, Inc.