Innovative UV-Responsive Self-Healing Polyacrylate Coatings for Enhanced Durability in Functional Applications

Polyacrylate was widely used in textiles, leather, and functional coatings due to its excellent film formation and flexibility. However, its durability was compromised by mechanical damage and poor water resistance. This study aimed to design a UV-induced self-healing polyacrylate coating (PXD) using vinyl-modified coumarin and acrylate monomers based on photoreversible covalent and hydrophobic interactions. The effect of the coumarin structure on the mechanical and self-healing properties was systematically examined. Results showed that increasing polymer chain flexibility, extending the distance between coumarin structures and the main chain, and raising the healing temperature enhanced self-healing efficiency. The PXD samples achieved over 84% healing efficiency after 8 h of 365 nm UV irradiation at 60°C, with scratches approximately 15 μm wide nearly fully healed within 2 h. Molecular dynamics simulations confirmed the influence of monomer structure on polymer flexibility, and the PXD self-healing mechanism was clarified. PXD-5 also exhibited improved hydrophobicity and water resistance, particularly under UV light, significantly enhancing leather durability. This development of UV-induced self-healing polyacrylate coatings represents a significant advancement in functional coating materials.