Notably Improved Dispersion of Carbon Black for High-Performance Natural Rubber Composites via Triazolinedione Click Chemistry

As the principal reinforcement filler, carbon black (CB) has been used in the rubber industry for over a century. However, the poor dispersity of CB in rubber matrices is still a bottleneck for preparing high-performance CB-filled rubber composites. In this contribution, we utilized the triazolinedione (TAD)-ene click chemistry to introduce the active urazole groups onto the natural rubber (NR) chains. The grafted urazole groups could be converted to the stable urazole radicals through the transformation from rubber macroradicals or under thermal oxidation and then trapped by CB to form the covalent interaction between rubber and CB. The enhanced interfacial interaction greatly improves the dispersion of CB in the NR matrix, leading to a significantly suppressed filler network. With a suitable TAD grafting ratio, the modulus and the wet-traction of NR/CB composite are improved, meanwhile the rolling resistance is strikingly reduced, which is very promising for the application of energy-saving tires.