A fast-healing and high-performance metallosupramolecular elastomer based on pyridine-Cu coordination

Abstract

Elastomers easily undergo a catastrophic failure as soon as a crack is introduced by mechanical damage. Thus, it is extremely important for elastomers to possess fast healing ability, which enables the quick reparation of cracks. However, developing elastomers with fast self-healing ability and high mechanical strength is highly challenging. Herein, we fabricate a metallosupramolecular elastomer by facilely introducing pyridine-Cu coordination into a copolymer of ethyl acrylate and vinyl pyridine. Interestingly, the pyridine-Cu coordination has a strong photothermal effect, which readily increases the sample temperature to 60°C in 30 s under near-infrared light. At this temperature, the sticky reptation modes are activated and thus serve as the driving force for network reorganization and fast self-healing of the metallosupramolecular elastomer. Albeit with a tensile strength of 10 MPa, the scratched and completely fractured samples can be healed within 2 min and 3 h, respectively. Moreover, during the damage and healing processes, the break and reformation of the coordination bonds can be tracked through laser confocal micro-Raman spectroscopy. This provides a microscopic methodology to monitor the bond-level healing kinetics of metallosupramolecular polymers. [Figure not available: see fulltext.]