Influence of a novel coupling agent on the performance of recovered carbon black filled natural rubber

Using recovered carbon black (rCB) from end-of-life tires to replace commercialized carbon blacks has drawn great attention in recent years. But rCB has poor reinforcement properties in comparison with such commercial carbon blacks like carbon black N330 when used in tire rubber composites. In this study, carbon black N330 was replaced at different proportions (50% and 100%) by rCB in natural rubber (NR) compounds used for tire tread rubber. The influence of a novel coupling agent, sodium (Z)-4-((4-aminophenyl) amino)-4-oxobut-2-enoate, on the reinforcement properties of rCB was studied. The addition of the coupling agent improved the dispersion of rCB and increased the content of bound rubber of NR compounds, and increased tensile strength, modulus at 100% and 300% strains of NR vulcanizates. The coupling agent also weakened the Payne effect and reduced the rolling resistance of NR vulcanizates filled rCB. Using the coupling agent is a simple and effective approach to the high-valued application of rCB in NR.