| abstract |
FIELD: polymer production. SUBSTANCE: invention relates to thermoelastolayers useful in fabrication of rubber products and sole materials as well as for modifying plastics and bitumens. These materials, constituting block copolymers of A-B-A type where a is monovinylaromatic compound block and B conjugated diene block, are produced by block-copolymerization of vinylaromatic compounds with diene hydrocarbons in organic solvent medium in presence of organolithium compound and a polar additive followed by conjugating living di-block copolymers by a carboxylic acid ester. In particular, as conjugating agent, ethyl acetate may be used being added in two steps: in the beginning of conjugation process, 80-90% of total ethyl acetate amount is added and the rest is added 30 min later. As polar additive, methyl-tert-butyl ether is used. Organolithium compound/ethyl acetate/methyl-tert-butyl ether molar ratio is 1:0.5:(2-0.5). EFFECT: optimized process parameters. 1 tbl |