Friction properties of epoxidised natural rubber based tyre treads

Abstract

Implementation of UNECE R117 regulation has upsurge great attention for tyres to comply with stringent safety and environment requirements on wet grip, rolling resistance and noise. In early study, utilization of Epoxidised Natural Rubber 25 with silica as tyre tread component has significantly improved tyre wet grip performance alongside enhancing noise and rolling resistance characteristics. In the science of rubber friction, contribution of dynamic properties has been identified as a major factor in rubber friction properties on rough surfaces. On the other hand, the dynamic properties for rubber are deformation frequency and temperature dependent. Therefore, external factors such as load and surface roughness which lead to change in deformation frequency and temperature beside material properties such as adhesion, strength and hardness will influence frictional properties of rubber. In the experimental, the effect of load and surface roughness on friction properties of the different types of tyre tread rubber filled with silica namely Epoxidised Natural Rubber 25 and Epoxidised Natural Rubber 50 were determined and evaluated. The factors that might influence the friction properties such as physical strength and hardness were analyzed and discussed. From the experiment, increases of load and surface roughness decreasing the coefficient of friction of the tread rubbers beside several factors such as adhesion, hysteresis and hardness might influencing the friction properties.