Coordinated control study of oil, wax, and antioxidants on tire sidewall rubber discoloration and fatigue properties

Abstract Sidewall discoloration and fatigue directly affect the aesthetic value and functional efficiency of tires during their service life. This study designed L9 orthogonal experiments with oil, wax, and antioxidant as factors to study their effects on the discoloration and fatigue performance of tire sidewall rubber. Molecular dynamics simulation calculations, nonlinear finite element analysis, and modern characterization methods were adopted for the investigation. The findings indicated that antioxidant precipitation was the main cause of sidewall discoloration; aromatic oil accelerated sidewall discoloration and the expansion of tire sidewall fatigue cracks; and microcrystalline wax enhanced the fatigue properties of rubber compounds by halting the aging and breakdown of rubber molecular chains. This paper provides insights into the coordinated control and formulation optimization of tire sidewall material discoloration and fatigue life. Furthermore, it helps to reduce waste tires and sidewall chemical release into the environment.