Design of Coordination-Crosslinked Nitrile Rubber with Self-Healing and Reprocessing Ability

In this work, we describe a simple approach to design of a coordination crosslinked elastomer with extraordinary mechanical properties: self-healing and recycling abilities by introducing Co-cyano coordination into nitrile rubber(NBR) matrix. The formation of reversible coordination crosslink network results in good mechanical properties superior to conventional sulfur-cured NBR, such as high stretchability and toughness. The reversibility of metal-ligand bond endows the polymer with self-healing capability and recycling or reprocessing abilities by rearrangement at elevated temperature. The fully cut samples after self-healing or reprocessing can restore their original tensile strength. It is also worth noting that the reclaimed NBR exhibited higher modulus than its original sample due to the compensation of new metal-ligand bonds formed during heating. This study provides possibilities to extend lifetime, reshaping and recycling capabilities of commercial rubber and reduce toxicity and environmental issues caused by waste rubber.