Patent ID: 7572851

Claim:
A process for preparing a silica/rubber blend which comprises (1) dispersing silica, a silica coupling agent, and a low molecular weight end-group functionalized diene rubber throughout a cement of a conventional rubbery polymer wherein the silica, the silica coupling agent, and the low molecular weight end-group functionalized diene rubber are dispersed throughout the cement of the conventional rubbery polymer at a minimum temperature of about 25° C. and a maximum temperature of 130° C. wherein the low molecular weight end-group functionalized diene rubber has a weight average molecular weight which is within the range of 50,000 to 200,000, wherein the low molecular weight end-group functionalized diene rubber is not a black polymer, wherein the cement of the conventional rubbery polymer is comprised of the conventional rubbery polymer and an organic solvent, and wherein the silica is present at a level which is within the range of 40 phr to 200 phr, and (2) subsequently recovering the silica/rubber blend from the organic solvent.