METHOD OF PREPARING BUTYL RUBBER Russian patent published in 2000 - IPC

FIELD: preparation of synthetic rubbers, more particularly butyl rubber. SUBSTANCE: method is carried out by copolymerization of isobutylene with diene hydrocarbon in the presence of Friedel-Crafts catalyst in methyl chloride diluent or hydrocarbon solvent. Method comprises deactivation of catalyst, degassing of rubber in the presence of rubber crumb antiagglomerator and antioxidant and also concentration of rubber crumb and drying thereof. Rubber crumb antiagglomerator and antioxidant and also concentration of rubber crumb and drying thereof. Rubber crumb antiagglomerator and antioxidant are added separately. After addition of antiagglomerator 90-98% of methyl chloride diluent or hydrocarbon solvent are distilled off from rubber dispersion, and as son as pH of 6.5-7.4 of rubber dispersion is attained, antioxidant is added to stabilize rubber in one or two steps. Method makes it possible to prepare rubber with stable (white) color, reduce consumption of stock and antioxidant, and make rubber more homogeneous. EFFECT: more efficient preparation method. 9 ex