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

FIELD: preparation of butyl rubber used for manufacture of outhomobile chambers, rubber products and halobutyl rubber. SUBSTANCE: method comprises preparing isobutylene, preparing blend and copolymerizing isobutylene with isoprene in methyl chloride diluent in the presence of Friedelcrafts catalyst, deactivating catalyst, degassing rubber, processing unpolymerized monomers and diluent by condensation, compression, drying and rectification, isolating and drying the rubber. Method comprises separating isobutylene which contains isoprene, isobutylene dimers and heavy residue into two flows, first flow, in amount of 30-70% based on total weight is directed to prepare blend, and second flow, in amount of 70-30% based on total weight, is directed for removal of butenes and butadiene in combination with isobutylene- containing fraction of hydrocarbons in process for preparing isobutylene. Isobutylene is isolated by rectification in two stages. EFFECT: lower power consumption and improved quality of rubber. 2 cl, 12 ex, 1 dwg