Effects of silica/carbon black hybrid filler on mechanical properties and mophology of styrene butadiene rubber-acrylonitrile butadient rubber blends

Abstract

Carbon black (CB) and silica have been used as the reinforcement fillers of rubber composites. As the each filler possesses its own advantages, the use of silica/CB blends could increase the mechanical, dynamic properties, oil resistance and compression set. However, the appropriate silica/CB ratio giving rise to the optimum properties needs to be study. In this work, the effect of silica/CB hybrid filler on mechanical properties of SBR/NBR blends were studied and the variables are blending ratio of SBR/NBR blends, filler content and ratio of silica/CB hybrid filler. The combination of sulfur and dicumylperoxide as vulcanizing systems was employed. To improve interaction between silica and rubber matrix, 3 types of silane coupling agent, γ-mercaptopropylmethoxysilane, γ- glycidoxypropyltrimethoxysilane and vinyl-tris-(2-methoxyethoxy) silane were used. The effects of silica/CB hybrid filler and coupling agent in rubber compound on tensile strength, modulus, and compression set and oil resistance were analyzed. This rubber blends (SBR/NBR=30/70) with 50 phr silica/CB hybrid filler modified with γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropy-lmethoxysilane, vinyltris-( 2-methoxyethoxy) silane exhibited good mechanical properties oil resistance and compression set and could be used as o-ring for motor oil medium resistance (ASTM oil no.1 and brake fluid).