Effect of Processing Additives on Carbon Black Dispersion and Grip Property of High-Performance Tire Tread Compound

Abstract

Abstract Rubber and carbon black compounds show complex behaviors in their mixing process due to their complicated microcomposite structure. Therefore, establishing a clear relationship between the mixing state of the rubber compound and the physical properties of its cured rubber has still remained to be solved in spite of formidable efforts by many rubber technologists. This paper investigated the influence of a processing additive on the carbon black incorporation and its dispersion behavior by inspecting Banbury power curves. From this investigation, we considered that good wettability toward the carbon black surface was necessary for processing additives in order to improve carbon black dispersion. The function of the processing additive was thought to enhance the surface lubrication of carbon black for disagglomeration in the early steps of mixing. The dry grip properties of a tire was estimated from the temperature dependence of dynamic viscoelastic properties of rubber compounds, with improved carbon black dispersion due to the processing additive; and it was confirmed by an actual tire running evaluation. Consequently, we found that tread compounds with improved carbon black dispersion had a remarkable effect on tire dry-grip properties at high temperatures.