REACTIONS OF SILICA-SILANE RUBBER AND PROPERTIES OF SILANESILICA/SOLUTION-POLYMERIZED STYRENE-BUTAMENE RUBBER COMPOSITE

Silane coupling agents can effectively improve the silica dispersion in rubber matrix and strengthen the interfacial interaction, and they have been widely used in tire treads to achieve low rolling resistance. 3-mercaptopropyl-ethoxybis(tridecyl-pentaethoxy-siloxane) (Si747) is a new coupling agent, and the temperature effects on the reactions between Si747 and silica and between Si747 and solution-polymerized styrene butadiene rubber (SSBR) were investigated via Fourier transform infrared spectroscopy, thermogravimetric analysis, and solid-state C-13 nuclear magnetic resonance in the present study. The results show that the Si747 grafting degree on the silica surface increases with increasing temperature, the cross-linking reaction between Si747 and SSBR can occur at 130 degrees C, and the reaction degree gradually increases with enhancing temperature. The silane-silica/SSBR composites were prepared at different in situ modification temperatures, and the temperature effects on the bound rubber content, filler dispersion, mechanical properties, and viscoelastic properties were investigated. It reveals that slightly pre-cross-linking between Si747 and SSBR lowers the tans at 60 degrees C of the SSBR/silane-silica composites, and in situ modification at 150 degrees C achieves a combination of low rolling resistance and high wet grip for silane-silica/SSBR composites.