| abstract |
A method for preparation of a rubber composition comprising of at least two diene-based elastomers with silica is disclosed. The method comprises, based on parts by weight per 100 parts by weight rubber (phr), a preparation of a first masterbatch comprising at least two conjugated diene-based elastomers, from 40 to 200 phr of a filler comprising rubber reinforcing carbon black and silica, preferably precipitated silica, and a silica coupling agent for the silica having a moiety reactive with hydroxyl groups on the silica and another different moiety interactive with the conjugated diene-based elastomers; and a preparation of a second masterbatch comprising at least two conjugated diene-based elastomers, and from 40 to 200 phr of a filler comprising rubber reinforcing carbon black and silica, preferably precipitated silica, wherein the silica is provided as a silica pre-treated with a silica coupling agent having a moiety reactive with hydroxyl groups on the silica and another different moiety interactive with the conjugated diene-based elastomers prior to adding the silica to the at least two conjugated diene-based elastomers; blending the first and second masterbatches together to form a blended rubber composition together with sulfur curatives comprising sulfur and at least one sulfur vulcanization accelerator, or thereafter blending sulfur curatives with the blended rubber composition where the sulfur curatives comprise sulfur and at least one sulfur vulcanization accelerator. |