In the last years, the European Union (EU) put a particular focus on the reduction of the greenhouse emissions. Since passenger cars are responsible for roughly 13% of the total CO2 emission in the EU it is of great importance to develop new tire tread formulations which can decrease significantly the overall fuel consumption of vehicles. One approach to reach the goal of lowering the carbon footprint of tires is the introduction of new types of polymers which reduce the rolling resistance.
In the current study, the effect of different functionalized polymers is studied. Therefore, two different types of (functionalized) Butadiene Rubber (BR) and two types of Styrene-Butadiene Rubber (S-SBR) are blended together in various ratios. Moreover, two different types of highly dispersible silica with different reinforcement potentials are used inside the rubber compounds. In a first step, the influence of both types of silica on the processing behavior is discussed for all blends. The Mooney viscosity, Payne effect and macro filler dispersion of the compounds are analyzed to investigate the effect of the functional groups grafted on the polymer chain.
In a second step, the dynamical and mechanical properties of the polymer blends are discussed. The hardness and stress / strain behavior are evaluated and the tan d at 0°C and 60°C are analyzed, which are used as lab indicators for the wet grip and rolling resistance of the tire. In this way, the potential of newly developed functionalized polymers for passenger car tire tread compounds can be assessed.