Improvement of properties of silica-filled styrene-butadiene rubber compounds using acrylonitrile-butadiene rubber

Since silica has strong filler-filler interactions and adsorbs polar materi als, a silica-filled rubber compound has a poor dispersion of the filler an d poor cure characteristics. Improvement of the properties of silica-filled styrene-butadiene rubber (SBR) compounds was studied using acrylonitrile-b utadiene rubber (NBR). Viscosities and bound rubber contents of the compoun ds became lower by adding NBR to the compound. Cure characteristics of the compounds were improved by adding NBR. Physical properties such as modulus, tensile strength, heat buildup, abrasion, and crack resistance were also i mproved by adding NBR. Both wet traction and rolling resistance of the vulc anizates containing NBR were better than were those of the vulcanizate with out NBR. The NBR effects in the silica-filled SBR compounds were compared w ith the carbon black-filled compounds. (C) 2000 John Wiley & Sons, Inc.