| 摘要 |
1,125,832. Treating ethylene-vinyl ester copolymers. STAMICARBON N.V. 2 May, 1966 [7 May, 1965], No. 19312/66. Heading C3P. Ethylene/vinyl ester copolymers are pyrolysed by heating at 225‹ to 350‹ C. and at least 90 atmospheres in the presence of a diluent. The vinyl ester may be vinyl acetate, propionate, butyrate or benzoate. The diluent may be ethylene, benzene, xylene, toluene, cyclohexane or hexane. When ethylene is used pyrolysis is preferably effected in the presence of a radical trap, e.g. hydroquinone or 4,4-thiobis-(6-t-butylm-cresol). The resulting unsaturated polymers are sulphur vulcanizable. |
