1. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201600, China
2. Jiangsu Wansheng Dawei Chemical Co., Ltd., Taixing 225400, China
3. Liaoning Provincial Key Laboratory of Novel Micro-Nano Functional Materials, Liaoning PetrochemicalUniversity, Fushun 113001, China
Self-healing polyurethane elastomers (BIMU-LPU) with linear structures containing dynamic imidazolium-urea bonds (BIMU) were prepared by reacting 2,2-diimidazolylmethane (BIM) and poly(tetrahydrofuran)glycol (PTMG) with isoflurane diisocyanate (IPDI). Introduction of Cu (II) into the polymer network of BIMU-LPU constructed a polyurethane elastomer (Cu-BIMU-LPU) with a physical cross-linking structure through the formation of coordination compounds between imidazole and copper ions. The structure of the material was characterized using nuclear magnetic resonance hydrogen spectroscopy and Fourier infrared spectroscopy, the thermal properties of the material were characterized using dynamic thermo-mechanical analyzer and thermogravimetric analyzer, the high-temperature dissociation of imidazoliumurea bonds was analyzed by elevated temperature infrared spectroscopy, the mechanical and self-healing properties of the material were tested using an electronic universal material testing machine, and the elasticity of the material was examined by cyclic tensile tests. The results showed that the synthesized Cu-BIMU-LPU had high tensile ((1230±93)%) and good tensile strength ((7.31±0.98) MPa), and recovered (95.1±2.9)% of the original tensile strength after healing at 70 ℃ for 2 h. Composite conductor wrapped with gallium-indiumtin eutectic alloy were subsequently prepared by using Cu-BIMU-LPU as the sheath material. The composite conductor could light up the light-emitting diode when it was stretched to more than two times of the original length after cutting and healing, showing the good application prospect of this material in the field of flexible electronic devices.