Patent ID: 7473724
Filing Date: 2009-01-06
Classification: B60C

Abstract:
1. A process of preparing a rubber composition which comprises the steps of: (A) blending, based upon parts by weight per 100 parts by weight rubber (phr): (B) thereafter adding and blending sulfur curative therewith; characterized in that said precipitated silica aggregates are treated with a modifier selected from a fatty alcohol and epoxidized soybean oil and their mixtures in the absence of and prior to said addition of said sulfur curative addition by pre-treating said precipitated silica aggregates with said modifier to form a pre-formed silica/modifier composite as a reaction product thereof and blending said pre-formed silica/modifier composite with said conjugated diene-based elastomer(s), followed by reacting said pre-formed silica/modifier composite with a coupling agent in situ within said conjugated diene-based elastomer(s) to form a silica/modifier/coupling agent composite thereof wherein said fatty alcohol is selected from at least one of 1 -octanol, 1 -decanol, 1 -dodecanol, 1 -tetradecanol, 1 -hexadecanol, 1 -octadecanol, 1 -eicosanol, 1 -docosanol, 1 -tetracosanol, 1-hexacosanol, or 1 -octacosanol, and their mixtures; wherein said coupling agent is selected from bis(ω-trialkoxysilylalkyl) polysulfide having an average of from about 2 to about 4 connecting sulfur atoms in its polysulfidic bridge, or ω-mercaptoalkyltrialkoxysilane, or ω-mercaptoalkyltrialkoxysilane having its mercapto moiety blocked from pre-reacting with hydroxyl groups contained on said precipitated silica aggregates prior to unblocking said blocked mercapto moiety.