Cure Characteristics and Mechanical Properties of Vinyltriethoxysilane Grafted Styrene-Butadiene Rubber/Silica Blends

Graft polymerization of vinyltriethoxysilane (VTES) onto styrene-butadiene rubber (SBR) was carried out in latex using potassium peroxydisulfate as an initiator. Then SBR-g-VTES/silica, SBR/TESPT/silica and SBR-g-VTES/TESPT/silica were prepared by mechanical mixing with different silica loading. The silica particles dispersed uniformly in the SBR-g-VTES networks. Among the three composites, the SBR-g-VTES/Silica blends show the highest of all. The t ₉₀ of SBR-g-VTES/TESPT/Silica composites is the shortest of all. On the other hand, the SBR-g-VTES/TESPT/silica composites exhibit highest tensile strength and hardness of all. The SBR-g-VTES/silica composites show higher tensile strength and hardness than SBR/TESPT/silica. The tanδ value (loss tangent) at -20-0°C of SBR-g-VTES/silica is slightly higher than that of SBR/TESPT/silica.