Organo bifunctional silane (TESPD) is added into silica containing NBR/PVC blend and its effects are investigated with respect to the vulcanization property, the processability, and the physical property. The addition of the TESPD into silica filled NBR/PVC compound increases the degree of crosslinking by formation of a strong three-dimensional network structure between silica surface and rubber matrix via coupling reaction, which results in improved mechanical properties. It also improves the processability of the compound compared to the Control compound. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012