REDUCTION OF RESIDUAL N-BUTYL ACRYLATE SENSITIZER IN RADIATION VULCANIZED NATURAL RUBBER LATEX

Radiation vulcanization of natural rubber latex needs n-butyl acrylate (n-BA) to lessen required irradiation dose. Considerable amount of n-BA remains in the latex after the completion of radiation vulcanization and tends to pollute the working environment in a dipping factory. A study has been carried out to reduce the residual n-BA after the radiation vulcanization. About 40% of added n-BA was found in the latex after irradiation to 20kGy. Hydrolysis of n-BA was effective for reduction of the residual n-BA in the latex. No n-BA was found in the latex when the latex was stored for 4 weeks at room temperature due to its hydrolysis. Heating of the latex was effective to accelerate the rate of hydrolysis of n-BA. Almost all of n-BA in the latex was hydrolyzed when the latex was heated for 4 hours at 80°C. Tensile strength of the latex films slightly decreased by heating treatment of the latex, but gradually recovered as storage time extended. Low viscosity was attained by the heat treatment of the latex.