Cellulose graft copolymers. IV. Graft copolymerization of methacrylonitrile with γ‐irradiated cellulose from DMSO–, acetone–, and methanol–water systems

Methacrylonitrile was graft‐copolymerized from DMSO–, acetone–, and methanol–water systems with γ‐irradiated, purified cotton cellulose. The relative extents of scavenging of the free radicals in the irradiated cellulose after immersion in the solvents for 3 min at 25°C, as determined by electron spin resonance spectroscopy, were: methanol (77%) > water (70%) ≫ acetone (5%) > DMSO (0%). After immersion of irradiated cellulose in the solvents for 60 min at 25°C, the relative extents of scavenging of the radicals were: methanol, water (80–85%) > DMSO (80%) > acetone (62%). From these data, it would appear that the overall rates of diffusion of methanol and water into the fibrous macrostructure were greater than the rates of diffusion of DMSO and acetone into the structure. The relative radiochemical yields of the graft copolymerization reactions of methacrylonitrile with irradiated cellulose in the different solvents were: water ≫ DMSO > methanol ≫ acetone. The addition of water to the systems increased the yields of the reactions.