| abstract |
The invention is directed to a process for the production of rubber composition, wherein the rubber composition comprises 100 parts by weight of elastomer. The process comprises the steps of n(A) mixing a first composition comprising 30 to 110 phr of a silica filler and 20 to 90 phr of a diene based elastomer selected from cis 1,4-polyisoprene rubber (natural or synthetic), 3,4-polyisoprene rubber, styrene/isoprene/butadiene rubber, emulsion and solution polymerization derived styrene/butadiene rubbers, and cis 1,4-polybutadiene rubbers, to form a first nonproductive compound; n(B) mixing a second composition comprising from 10 to 80 phr of a rubber containing a nitrile moiety and the first nonproductive compound to form a second nonproductive compound; and n(C) mixing a third composition comprising curatives and the second nonproductive compound to form a productive compound. |