| abstract |
The present invention is directed to a rubber composition comprising, based on 100 parts by weight of elastomer (phr), n(A) from 60 to 90 phr of a solution polymerized styrene-butadiene rubber functionalized with an alkoxysilane group and at least one functional group selected from the group consisting of primary amines and thiols; n(B) from 40 to 10 phr of polybutadiene having a microstructure comprising 96 to 99 percent cis 1,4-isomeric units, 0.1 to 1 percent trans 1,4-isomeric units and from 1 to 3 percent vinyl 1,2-isomeric units; a number average molecular weight (Mn) in a range of from 75,000 to 150,000 and a heterogeneity index (Mw/Mn) in a range of from 3/1 to 5/1; and n(C) from 50 to 150 phr of silica. n The invention is also directed to a tire with such a rubber composition. |