Heading towards a fully sustainable tire tread compound: use of bio-based resins

The automotive industry is in constant development, with a special focus on increasing the sustainability of tires while maintaining their high performance. One of the most used approaches to reach this goal is the use of bio-based raw materials. On this basis, this work aims to substitute the traditional plasticizers used in tire tread compounds (obtained from non-renewable resources) by bio-based resins. These materials can function as plasticizers in rubber compounds and in contrast with vegetable oils, they are not in conflict with the food industry. With this purpose, four different bio-based resins with different properties were analyzed. The effect of these resins on the in-rubber properties was studied in a silica-filled styrene butadiene rubber (SBR)/polybutadiene rubber (BR) compound. The use of these natural products resulted in similar or improved mechanical properties, higher crosslink density, improved dispersion and higher wet grip indicator compared to a TDAE-based compound. However, the addition of the resins also led to a deterioration in the abrasion resistance and the rolling resistance indicator.