PROCESS OF OBTENTION OF COPOLYMERS IN BLOCKS ABC WITH BASE IN BUTADIENE AND ISOPRENE AND ITS APPLICATION

摘要

ABC block copolymers on the basis of butadiene, isoprene and optionally styrene, are provided by a polymerization process wherein the resultant block copolymer comprises: about 40 to 75 wt % of a block A based on butadiene (uniformly distributed vinyl group content less than about 15 wt %), up to about 25 wt % of a block B based on butadiene and isoprene (vinyl content less than about 15 wt %) or based on butadiene (vinyl content more than about 75 wt %) about 20 to 55 wt % of a block C based on butadiene and isoprene (vinyl content more than about 75 wt %). The ABC block copolymers are useful for the production of tire treads.