Interaction of vulcanization and reinforcement of CB on dynamic property of NR characterized by RPA2000

Vulcanization and reinforcement are two most important approaches to improve rubber properties. Effect of carbon black (CB) load level on curing process and properties of Natural rubber (NR) compounds and vulcanizates and interaction between vulcanization and reinforcement were characterized by Rubber Processing Analyzer (RPA2000). The incorporation of CB shortened the scorch delay time and prolonged curing time. Only after CB loading level reached about 20 phr, could effective CB network be formed that contributed to the formation of “Payne effect.” Dynamic elastic shear modulus G′ of filled NR compounds had a stronger dependence on strain than that of unfilled NR. There was a synergism between vulcanization and reinforcement on the improvement of shear modulus of NR compounds and vulcanizates. The elastic recovery of vulcanizates restricted the break of CB network through the rubber bridges formed between CB particles and helped the reformation of broken CB network. All these action amplified the reinforcement of CB.