Patent ID: 8357733

Claim:
A process for the preparation of silica masterbatch, comprising the steps of: (a) hydrophobating silica by: (i) dissolving a trimethoxy silane coupling agent in a mixture of alcohol, acid and water to provide a trimethoxy silane coupling agent solution, wherein the amount of alcohol and water is at least 70% water by weight, wherein the coupling agent has the capability of chemically reacting with the surface of the silica to bond the coupling agent to the silica, and wherein the coupling agent has the capability of bonding to rubber during vulcanization of the rubber; and (ii) mixing the trimethoxy silane coupling agent solution with silica and adding a base to increase the pH to form a compatibilized silica slurry; (b) making a polymer latex and mixing the compatibilized silica slurry with the polymer latex; (c) coagulating the polymer latex from step (b) to form a crumb, wherein a calcium salt is used as a coagulating agent; (d) dewatering the coagulated crumb; and (e) drying the dewatered crumb, wherein the process does not require carbon black.