LAUSR

Extensive use of zinc oxide (ZnO) and accelerators such as diphenyl guanidine (DPG) in the vulcanization of rubber composites entail potential environmental risks. These are pervasive contaminants of roadway runoff originating from tire wear particles (TWPs). Herein, the effect of phosphonium ionic liquids (PILs) in styrene-butadiene rubber compounds was demonstrated with reduced ZnO loading and nil DPG to minimize the environmental footprint of the vulcanization process. The structure and chemistry of PILs were found to be the influencing parameters impelling the cross-linking kinetics, enabling shorter induction times. The generation of active Zn2+ sites by PILs was examined through FTIR, calorimetry, and MD simulations. From a tire application perspective, the PILs not only enhanced the cure kinetics but also improved the dynamic-mechanical behaviour of the rubber composites. Consequently, the harm caused by TWPs to the atmosphere, fuel intake, and CO2 emissions was minimal, thereby confirming the potential use of PILs in the tire industry.