Patent ID: 7307121

Claim:
A process for preparing a silica/rubber blend which comprises dispersing a slurry of silica throughout a cement of a rubbery polymer, wherein the slurry of silica is made by dispersing (1) a first silica coupling agent having the structural formula Z-Alk-SH, (2) a second silica coupling agent having a structural formula selected from the group consisting of Z-Alk-S n -Alk-Z, Z-Alk-S n -Alk, Z-Alk, and Si(OR 1 ) 4 , and (3) the silica throughout an organic solvent, and subsequently recovering the silica/rubber blend from the organic solvent, wherein the first silica coupling agent having the structural formula Z-Alk-SH is present at a level of 1 weight percent to 20 weight percent, based upon the total amount of the first silica coupling agent and the second silica coupling agent utilized in making the silica/rubber blend.