Processability Improvement of SBR/Silica Compounds Using Liquid Rubbers

Abstract

This study investigates the effect of liquid rubber on improving the processability of SBR/silica-based tread compounds for tires. High-performance formulations often face challenges in mixing and processing during scale-up, leading to reduced productivity. Liquid rubber, traditionally used to improve processability in high-hardness compounds, was applied here by partially replacing conventional plasticizers with liquid polyisoprene. Significant improvements were observed in Mooney viscosity, sheet flexibility, and surface smoothness. Importantly, key physical properties such as viscoelasticity were maintained, demonstrating that performance and processability can be balanced. Unlike traditional oils, liquid rubber co-crosslinks during vulcanization, offering long-term stability and reduced environmental impact. These findings suggest that liquid rubber is a promising additive for overcoming processing issues in high-performance rubber formulations, especially during scale-up in tire manufacturing.