Process for curing a modified polybutadiene glycol coating composition

Herein provided is a process for curing, with ionizing radiations (1 to 15 Mrad, 10 to 600 keV), a coating composition composed of 100 parts of a modified polybutadiene glycol (prepared by modifying the following α,ω-polybutadiene glycol HO-CH(C2H3)-CH2-(CH(C2H3)-CH2)sub(n)-CH(C2H3)-CH2-OH (MW 1,000-5,000) with an unsaturated carboxylic acid) and 10 to 50 parts of a vinyl monomer. After curing, the coating exhibits an excellent flexibility, a resistance to impact, bending, chemicals and water, and has good electrical insulating properties. In one example, 85 g of α,ω-polybutadiene glycol (MW 2,000) was reacted with 15 g of maleic anhydride and the product was dissolved into 50 g of α-methylstyrene. A molded article of acrylonitrile-styrene copolymer was coated with the resulting solution and irradiated with electron beams (5 Mrad). The coating cured perfectly to give the article a soft appearance. (Kaichi, S.)