Advances in Reinforcing Particles for Tires

F. Rumpf, M. Morris
Cabot Corporation Rubber Blacks, US

Keywords: rubber polymers, automobile tires

Summary:

The rubber polymers used in the manufacture of tires have traditionally been reinforced with fine particles, notably carbon black and, more recently, precipitated silica. The reinforcement provided by these particles comes at the expense of increased hysteresis, which leads to a significant increase in rolling resistance and hence fuel consumption of the vehicle. Recent initiatives to improve fuel consumption and reduce CO2 emissions has led to renewed research aimed at improving the trade-off between reinforcement and hysteresis in tire materials, without neglecting the third critical tire property, traction. Controlling the physical and chemical interactions between particles and polymer is critical in meeting this objective. We have been able to develop improved particles for tire applications based on two approaches. The first approach involves heterogeneous particles containing both carbon and silica within the same particle. The second involves chemical attachment of specific functional groups to the surface of carbon black. For each approach we will give examples showing particle properties, rubber composite properties and put forward hypotheses for how the performance improvements are achieved.