PROCESS FOR THE PREPARATION OF HIGH MOLECULAR WEIGHT, HIGH UNSATURATION ISOBUTYLENE-CONJUGATED DIENE COPOLYMERS

摘要

1459642 Isoolefin-conjugated diene copolymerization EXXON RESEARCH & ENG CO 3 April 1974 [6 April 1973] 14777/74 Heading C3P Isoolefins and conjugated dienes are copolymerized at a temperature below - 100‹ C. and in the presence of a hydrocarbylaluminium dihalide catalyst. The copolymerization is carried out as a solution process, in the presence of 5 to 40 volume per cent (based on solvent and monomers) of an inert solvent and to a conversion level of 2 to 20% to produce a polymer having a number average molecular weight of at least 120,000 and an unsaturation (i.e. diene) level of 8 to 40 mole per cent. Examples refer to the copolymerization of isobutylene with isoprene or cyclopentadiene or a mixture thereof in the presence of methyl cyclohexane or heptane as cosolvent and of EtAlCl 2 , MeAlCl 2 , iBuAlCl 2 , EtAlBr 2 or (comparative) EtAlI 2 .