Preparation of NBR/Tannic acid composites by assembling a weak IPN structure

Abstract Sustainable self-reinforcement organic filler, which does not contribute to environmental pollution, has been realized in the rubber industry as an alternative to modifying inorganic fillers with coupling agents or preparing rubber fillers, such as carbon black, with petrochemical products that cause environmental problems. In this work, tannic acid (TA), the world's third largest class of plant components that are easily available, is used as a self-reinforcing organic filler to prepare nitrile–butadiene rubber/TA (NBR/T) composites. Results show that TA can melt partially under vulcanization to assemble a weak interpenetrating polymer network (IPN) structure by hydrogen bonds under cooling, which is responsible for the dramatic increase in the mechanical and flexible properties of NBR/T composites even at low TA dosage. This finding provides a new perspective in preparing high-performance and sustainable rubber composites without sacrificing fossil fuels or non-renewable environmental resources.