BRINGING INNOVATION TO THE SURFACE: FUNCTIONALIZED SILICAS FOR IMPROVED NATURAL RUBBER TRUCK TIRE VULCANIZATES

摘要

The simultaneous improvement of rolling resistance, wear and traction, known as expanding the tire "magic" triangle, requires new approaches to rubber composite development. Precipitated silica has played a major role in the emergence of the green tire, which boasts a large improvement in rolling resistance compared to past technologies. The direct cross-linking of silica into a highly cross-linked polymer matrix, while minimizing interactions between silica particles, is believed to be of vital importance to desirable dynamic mechanical properties. In natural rubber, proteins and other non-rubber impurities present from its biosynthesis can preferentially adsorb to the silica surface, interfering with the in-situ reaction between precipitated silica and a coupling agent. Furthermore, increased dump temperatures, which may improve the coupling efficiency, have also been shown to degrade natural rubber. PPG's proprietary Agilon~(TM) performance silica technology platform solves this issue by modifying the silica surface with a mercaptoorganometallic species and a non-coupling agent which increases interaction between polymer chains and the silica surface. This solution also eliminates volatile organic compound (VOC) emissions and can offer a productivity improvement for compounders. Here we demonstrate that a new product in the Agilon performance silica technology platform, Agilon 454, can provide reduced rolling resistance, low heat build-up, high tensile strength and good tear strength without compromising wear in a 100 percent natural rubber model truck tire compound.