The Effect of Surface Area of Silicas on Their Reinforcing Performance to Styrene-butadiene Rubber Compounds

Abstract

The effect of the surface area of silicas on their reinforcing performance to styrene-butadiene rubber (SBR) compounds was systematically investigated. The feasibility of the Brunauer-Emmett-Teller surface area (S BET) as a parameter representing the characteristics of the silicas was discussed compared to the mesopore volume, c value, oil absorption, and uptake of silane. The increase in S BET of silicas caused a considerable increase in Mooney viscosity, minimum torque, and hysteresis loss of the silica-filled SBR compounds, while significantly enhancing their abrasion property. These changes were explained by the attrition between the hydrophilic silica surface and the hydrophobic rubber chains. As expected, the change in S BET did not induce any remarkable changes in the cure, processing, tensile, and dynamic properties of the silica-filled SBR compounds because the crosslinking density of the rubber chains mainly determined these properties.