XSBR/NR Rubber Blends Filled with Polystyrene-Encapsulated Nanosilica Prepared by in situ Differential Microemulsion Polymerization

Abstract

Rubber blends of caboxylated styrene butadiene rubber (XSBR) and natural rubber (NR) filled with polystyrene-encapsulated nanosilica (PS-nSiO 2) were prepared by latex compounding. The PS-nSiO2 synthesized by in situ differential microemulsion polymerization was used at 3 phr as the filler in three different XSBR/NR blend ratios (70/30, 50/50, and 30/70). The nanocomposite latex was cast into sheets on glass molds and cured in an oven. The specimens were examined for their tensile properties, dynamic mechanical properties, and thermal stability. The tensile strength and elongation at break were found to increase with increasing levels of NR in the rubber blends, but the modulus decreased. Moreover, the tensile properties, dynamic mechanical properties, and thermal stability were all improved by the addition of PS-nSiO2 within the blend systems.