Effect of the Chemical Composition on Fatigue Properties of Carbon Black-Filled Natural Rubber

Among factors affecting the fatigue resistance of rubber materials, network appears as one of the most important. Network forms during the vulcanization process, such that the nature and crosslinking length depend on the sulfur and accelerator content, as well as on the processing conditions (time, temperature, pressure). Although this topic has been widely studied, the relationship between the active chain density and the fatigue properties of the rubber has not yet been fully understood. The present study addresses the effect of network on the fatigue properties of natural rubber (NR). Several NR compositions have been defined, and different times and temperatures of vulcanization have been considered. Our results highlight and quantify the effect of the active chain density on the fatigue resistance, revealing the key significance of this parameter.