Agilon Performance Silicas in Natural Rubber Truck Tire Tread Compounds

The simultaneous improvement of rolling resistance, wear and traction, known as expanding the “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 present from its biosynthesis can preferentially adsorb to the silica surface, interfering with the in-situ coupling reaction. 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. This solution also eliminates Volatile organic compound (VOC) emissions and can offer a productivity improvement for compounders. Here we present results from our evaluation of filler(s) from the Agilon performance silica technology platform in natural rubber formulations, particularly for heavy duty tread compounds.