Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real time.Here,we report a strategy of a photo-responsive system ba...Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real time.Here,we report a strategy of a photo-responsive system based on hydrogen and ion bonds capable of performing self-healing process by ultraviolet wave-lengths,which is covalently cross-linked zinc-dimethylglyoxime-polyurethane coordination network with triple dynamic bonds.The recombination of hydrogen bond and metal coordination bond produces ef-fective healing performance.The self-healing behavior and temperature dependence of 3D micro-crack is investigated by molecular dynamics simulations to reveal the mechanism of self-healing at molecu-lar level.Moreover,the hybrid of copper-doped zinc oxide not only provides metal coordination bonds to enhance the self-healing rate,but also enhances the photothermal effect and anti-bacterial properties of polyurethane.Importantly,doping of copper generates more defects and forms a space charge layer on the surface of zinc oxide.The defects could trap surface electrons and holes,preventing the recom-bination of photo-induced electron-hole pairs,generating more heat through lattice vibration.Therefore,under ultraviolet light irradiation,the polyurethane can reach 62.7°C for 60 s,and the scratches of the polyurethane can be healed within 30 min and fully healed within 1 h.展开更多
基金supported by the National Natu-ral Science Foundation Joint Fund(No.U1806223)the National Natural Science Foundation of China(Nos.51572249,42076039)+1 种基金the Foundation of Key Laboratory of National Defense Science and Technology(No.JS220406)the Natural Science Foundation of Shandong Province(No.ZR2020ME016).
文摘Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real time.Here,we report a strategy of a photo-responsive system based on hydrogen and ion bonds capable of performing self-healing process by ultraviolet wave-lengths,which is covalently cross-linked zinc-dimethylglyoxime-polyurethane coordination network with triple dynamic bonds.The recombination of hydrogen bond and metal coordination bond produces ef-fective healing performance.The self-healing behavior and temperature dependence of 3D micro-crack is investigated by molecular dynamics simulations to reveal the mechanism of self-healing at molecu-lar level.Moreover,the hybrid of copper-doped zinc oxide not only provides metal coordination bonds to enhance the self-healing rate,but also enhances the photothermal effect and anti-bacterial properties of polyurethane.Importantly,doping of copper generates more defects and forms a space charge layer on the surface of zinc oxide.The defects could trap surface electrons and holes,preventing the recom-bination of photo-induced electron-hole pairs,generating more heat through lattice vibration.Therefore,under ultraviolet light irradiation,the polyurethane can reach 62.7°C for 60 s,and the scratches of the polyurethane can be healed within 30 min and fully healed within 1 h.
