| abstract |
The present invention relates to a process wherein a) a copolymer of C 4 to C 7 isoolefins and para-alkylstyrene is mixed with silica, and b) a general purpose rubber is mixed separately with silica, wherein at least one silane coupling agent is silica / copolymer or silica. / Mixing with at least one of the general purpose rubber blends, and c) mixing the silica / copolymer blend with the silica / general purpose rubber blend. Common silane coupling agents include bis (3-triethoxysilylpropyl) tetrasulfide, 3-thiocyanato-propyl-triethoxysilane, 3-mercaptopropyl-trimethoxy silane, one of the copolymers An embodiment of is a terpolymer of isobutylene, para-methylstyrene and bromo-paramethylstyrene. |