PROCESSES FOR MAKING SILANE, HYDROPHOBATED SILICA, SILICA MASTERBATCH AND RUBBER PRODUCTS

摘要

A process for making silica-filled rubber masterbatch using silica hydrophobated with a trimethoxy silane coupling agent. One embodiment uses a mixture of trimethoxy silanes, one or more of which react with rubber to bond the silica to the rubber, and one or more of which do not react with rubber, but do hydrophobate the silica. Hydrophobated silica is mixed with latex polymer and incorporated into rubber during coagulation of the latex, which is preferably coagulated with calcium chloride. The present invention further provides a process for making the trimethoxy silane coupling agents. Preferred trimethoxy silane coupling agents include bis-(3-trimethoxysilylpropyl)disulfide and bis-(3-trimethoxysilylpropyl)-tetrasulfide. Long scorch time of the inventive silica masterbatch allows rubber products, particularly tires, to be compounded at length.