Preparation of Grafted Long‐Lasting Aging‐Resistant Natural Rubber and Its Performance Study

ABSTRACT The molecular structure of natural rubber (NR) comprises several unsaturated double bonds, rendering it susceptible to aging, which diminishes the functional value of rubber goods. This study suggests a method for preparing grafted natural rubber to enhance its aging resistance. Using p‐aminodiphenylamine (PPDA) as a raw material, PPDA was grafted onto the NR matrix, resulting in the effective synthesis of aging‐resistant rubber (PPDA‐g‐NR). Experiments demonstrated that the PPDA‐g‐NR composites exhibit superior mechanical properties and resilience to thermal oxygen aging. In comparison to the ungrafted PPDA/NR composites, the migration rate of PPDA was markedly diminished. At a dosage of 2 phr of PPDA antioxidant, the natural rubber composites have the best comprehensive performance, demonstrated by enhancements in plasticity retention, crosslink density, Oxidation induction time, abrasion resistance, and compression fatigue properties resistance. The tensile strength of PPDA(2)‐g‐NR was enhanced by 52.05% in comparison to the unmodified NR. The aging coefficient rose, and the retention of crosslink density increased by 27.53% following thermal oxygen aging at 100°C for 120 h. The PPDA‐g‐NR composites have shown considerable resistance to long‐term thermal oxygen aging. Simultaneously, a thermo‐gravimetric analysis indicated that PPDA significantly enhances the thermal stability of natural rubber composites. This study offers an effective design methodology for the creation and formulation of durable, aging‐resistant natural rubber products.