AB BLOCK COPOLYMERS BASED ON BUTADIENE, ISOPRENE AND STYRENE, PROCESS FOR THEIR MANUFACTURE AND THEIR USE

摘要

AB block copolymers on the basis of butadiene (20 to 75%), isoprene (5 to 50%) and styrene (3 to 30%), process for their manufacture and their use are disclosed. The block copolymers according to the invention are composed of 30 to 90% of a block A and 70 to 10% of a block B, wherein each of the two blocks contains all three monomers. The mean vinyl and isopropenyl content of the block B is each at least 30% higher than that of block A. These block copolymers which can be manufactured in a simple process, exhibit a more or less broad damping curve, depending on the particularities of the process, and are useful in the manufacture of tyre treads.