Visible Light Responsive Self-Healing Polyurea Elastomers Driven by Dynamic Coordination for Underwater and Low-Temperature Applications

Abstract

Developing intelligent polymeric materials capable of self-healing under extreme conditions, such as underwater or in low-temperature environments, remains a significant challenge. Herein, we report a series of visible light responsive self-healing polyurea elastomers (denoted as PSHA-Zn). These elastomers are fabricated by integrating dynamic coordination units (PDB-Zn), derived from a novel phenyldiazobenzothiazole (PDB) derivative and zinc ions, into a polydimethylsiloxane (PDMS) based polymer backbone. Under visible light irradiation, these coordination motifs undergo rapid and reversible dissociation and recombination. This mechanism endows the PSHA-Zn elastomers with superior self-healing capabilities, achieving a tensile strength healing efficiency of up to 100%. Notably, the material achieves 100% healing efficiency even under ambient sunlight. Furthermore, the optimized PSHA-2-Zn exhibits robust self-healing performance under aqueous conditions and at an ultralow temperature of -60 °C, yielding tensile strength recovery efficiencies of 98.2% and 68.2%, respectively. This work presents a promising design strategy for smart polymeric materials intended for marine and polar applications.