Underwater Non‐Contact and Ultra‐Fast Adaptive Self‐Healing Elastomers Based on Programmable Dissociation of Dynamic Bonds

Abstract Most of the reported self‐healing materials focus on the structure and function recovery, the influence of the damage degree on the self‐healing process has been rarely studied. In this study, an elastomer with an adaptive self‐healing function is developed based on programmable dissociation of dynamic urea bonds. The stored entropy and reversible hydrogen bonding enable the elastomer with room‐temperature self‐healing performance as the scratch depth is less than 100 µm. Thermal treatment at 75 °C is capable of inducing the cleavage of secondary urea bonds, which accelerate the dissociation of the network, leading to the repair of the middle‐size damage. Continuous increasing the temperature to 120 °C enables the dissociation of primary urea bonds, which causes further dissociation of the network, resulting in the repair of large‐scale damage. This damage‐adaptive self‐healing performance can be well maintained in an aqueous environment, and obvious improvement in the healing rate is achieved due to the water‐accelerated dissociation of urea bonds. The underwater self‐healing rate is more than 360 times faster than that in the air. Incorporation of carbon nanotubes into the network enables remote self‐healing function due to the photo‐thermal transition after irradiated by NIR light, displaying great potential in underwater gas or liquid transportation.