Novel Additives for Simultaneous Improvement in Processing and Dynamic Stiffness in Silica Tread Compounds

Tire manufacturers are constantly seeking out new material technologies that can be leveraged to meet the ever increasing performance demands for improved fuel economy and vehicle handling and braking performance laid down by vehicle manufacturers and improved safety and tread-life demanded by tire buying consumers.  By creating new tread formulations utilizing high levels of HDS silica and silane coupling agents, tire manufacturers have delivered performance gains demanded by the market but these new formulas have proven to be substantially more difficult to process than their carbon black based predecessors.  While alternative silane coupling agents and conventional process additives have been introduced to help improve processing of high silica tread compounds, the processing gains achieved are only at the cost of substantially reduced compound physical properties and performance. For instance, low strain dynamic stiffness (G’) and compound modulus are compromised in silica passenger tread, both of which result in losses in tire handling and treadwear performance.  The authors have taken a holistic approach to additive design for use in silica-containing treads to create high performance process aids that provide substantial processing benefits with minimal trade-offs in desirable compound properties.