Enhancing Mechanical Properties of Rubber Composites via Hydroxylation and Silane Coupling of Carbon Black

Carbon black (CB) is the most important and commonly used reinforcing filler in the rubber industry. However, it is easy to agglomerate to form filler networks, restricting the improvement of the mechanical properties of the rubber composites. Here, we developed a method to modify the surface of CB via hydroxylation and silane coupling, which promotes dispersion and consequently improves the mechanical performance of rubber composites. The static and dynamic mechanical properties of the composites were evaluated using uniaxial tensile testing, dynamic thermomechanical analysis (DTMA), and dynamic compression fatigue testing. Our results showed that under an adequate hydroxylation condition, the mechanical strength of the composites could be increased by about 40% without sacrificing the fracture toughness, and the abrasion resistance could be improved by about 18%. Meanwhile, an appropriate modification of CB would also increase the dynamics hysteresis at 0 degrees C and decrease that at 60 degrees C synchronously. As the dynamics hysteresis at high temperature decreased, the dynamic heat build-up was reduced (by about 14%) without significantly affecting the dynamic permanent set. These findings highlight the potential of surface-modified CB in enhancing the performance of rubber composites, providing valuable insights for the development of high-performance rubber materials.