Solutions for Processing Challenges with An Advanced Silica-Silane System

The market share of silica-filled tire tread compounds for passenger cars is continuously growing. New developments are being introduced focusing on environmental aspects since ecological requirements become more and more stringent due to legal regulations worldwide. As a consequence, the new rubber silane VP Si 363^® which reduces the rolling resistance by more than 10% was introduced to the rubber industry. This reduction is reached by a higher coupling yield of the silane-polymer reaction based on a more efficient interaction of this new silane with the accelerator system.

Due to the chemical reaction between silica and silane taking place during the mixing process the use of silica requires a more controlled mixing procedure compared to the dispersive mixing of carbon black. For compounds containing the new VP Si 363^® an even more advanced mixing process with higher shear forces is necessary to guarantee low compound viscosities. The processing challenges are even more pronounced in compounds with this new rubber silane together with high surface area silica. The use of a special mixing procedure as well as the application of TESPT as process aid lead to good processing properties in this system.