Self‐healing natural rubber based on dynamic disulphide exchange towards fatigue lifetime extension

Abstract Dynamic disulphide exchange mechanism was introduced to promote self‐healing characteristics to natural rubber compound and the corresponding healing mechanism and mechanical properties are presented. The formation of reversible dynamic disulphide bonds within rubber molecular chains was evidenced via FTIR and the total crosslink density of dynamic disulphide crosslinks was quantitatively measured by equilibrium swelling test. Scanning Electron Microscopy (SEM) results revealed that the healed area of the fractured surface adhered well with minor scar on the contact surface, suggesting that intermolecular diffusion occur at the fracture surface. It was also found that the tensile strength and tear strength of the broken samples able to recover 91% and 103%, respectively, under thermal healing at 150°C for 10 min. The fatigue lifespan of the materials increased 154.9% compared with the conventional rubber. The successful fabrication of self‐healing natural rubber through dynamically reversible disulphide exchange mechanism would be expected to open up new opportunities for development of sustainable rubber products.