RUBBERY COMPOSITIONS COMPRISING A BLEND OF POLYMERS OR COPOLYMERS OF CONJUGATED DIENES, OR COPOLYMERS THEREOF WITH A VINYLAROMATIC COMPOUND

摘要

A B S T R A C TA composition comprising a blend consisting of polymers orcopolymers of one or more conjugated dienes having 4 or 5 carbon atoms permolecule, or copolymers thereof with a vinylaromatic compound, wherein oneportion (A) consists of at least 60% by weight of components which have beenmodified by branchings comprising at least 20 monomer units each, whileanother portion (B) consists of similarly modified branched and/or linearcomponents, with the proviso, that the intrinsic viscosity of the blend ofA and B is within the range of from 1.3 to 5 dl/g, the ratio of the intrinsicviscosities of A and B amounts to at least 3 and does not exceed 50, and theamount of portion A in the blend lies within the range of from 40 to 94% byweight. The composition of the present invention is useful for many importantapplications, particularly as base materials in the manufacture of heavy-dutytires for automotive vehicles.