PREPARATION OF BUTADIENE-STYRENE RUBBERS Russian patent published in 1997 - IPC

FIELD: synthetic rubber industry, more particularly preparation of butyl-styrene rubbers. SUBSTANCE: butyl-styrene rubbers are prepared by copolymerization of butadiene with styrene in hydrocarbon solvent in several in series connected reactors at 45-90 C in the presence of organolithium initiator. Copolymerization is carried out in the presence of cocatalyst additive of formula: C₆H₂(R₁)(R₂)(R₃)(OK), wherein R₁, R₂, R₃ are H or at cocatalyst to organolithium compound molar ratio of from 0.04: 1 to 0.2:1, respectively. In this case, cocatalyst is added in amount of 0.01 to 0.5 wt % based on total amount of comonomers. Fatty acids of formula RCOOH, wherein R is C₁₂-C₂₀ alkyl, are added together with cocatalyst into the last reactor. Fatty acids are added in amount of 0.005 to 0.8 wt % based on total amount of comonomers. EFFECT: more efficient preparation method. 2 tbl