Futao Sai,Haitao Zhang,Jianbo Qu,Jianyong Wang,Xiuzhong Zhu,Yang Bai,Peng Ye
Currently, the preparation and application of functional waterborne polyurethane has become a research hotspot in the field of polyurethane. In the present work, Different weight ratios of diacetyl oxime and coumarin diol were used as the reactive filler with isophorone diisocyanate (IPDI) and Poly propylene glycol (PPG) to prepare superior amine-response, self-healing and recyclable waterborne polyurethane films (WPU-x). Dynamic mechanical analysis was carried out to identify the self-healing properties of WPU-x. It was revealed that the WPU-2 film show an excellent self-healing capability based on the combination of the mobility of the soft segment, dynamic reaction of oxime carbamate bond and hydrogen bonds, and the mechanical properties self-healing efficiency can reach 91.11% after self-healing at 90 °C for 7 h. UV testing and fluorescence imaging results shown that WPU-2 film exhibit a rapid and concentration-dependent response to dimethylamine (DMA), and it also shows varying degrees of response to other organic amines. The WPU-2 film could be readily applied in cold chain transportation of shrimp and fish for real-time and visual monitoring the freshness of seafoods. At the same time, the WPU-2 film could be recycled via hot-pressing and solution casting. Therefore, this strategy provides some insights for preparing multi-functional waterborne polyurethane.
Recently, the self-healing and recyclability of waterborne polyurethane (WPU) has attracted significant research attention. Herein, different weight ratios of Diels-Alder (DA) diol and diacetyl oxime (DMG) were used as the reactive monomer with polytetramethylene ether glycol (PTMG), isophorone diisocyanate (IPDI) and dimethylolpropionic acid (DMPA). A series of thermal-driven self-healing and green recyclable waterborne polyurethane films (WPU-DMG x -DA y ) were prepared based on synergistic dynamic reactions of oxime-carbamate and DA bonds. We investigated the properties of WPU-DMG x -DA y emulsions by particle size and zeta potential tests, and the results show that these emulsions have excellent storage stability. The self-healing properties of WPU-DMG x -DA y films were identified by dynamic mechanical analysis . It was revealed that the WPU-DMG 4 -DA 4 film has the best self-healing capability, and the self-healing efficiency can reach 92. ± 0.1 % after self-healing at 120 °C for 4 h. The mechanism of the self-healing behavior was studied by Fourier transform infrared spectroscopy , and the effective reversibility of the oxime-carbamate and DA bonds were verified. In addition, thermal gravimetric analysis and tensile test results showed that the thermal stability and mechanical properties of the WPU-DMG x -DA y films were significantly improved. More importantly, the WPU-DMG 4 -DA 4 film can be dissolved in a mixed acetone/ethanol solvent at room temperature. The recycled polyurethane solution could be dispersed in water to obtain a WPU emulsion again. After being recycled three times, the recovery efficiency of the mechanical properties of the WPU-DMG 4 -DA 4 film was higher than 90.1 ± 0.1 %, and the recycled film maintained its thermal stability and self-healing behavior. Moreover, the synthetic leather obtained by compounding WPU-DMG 4 -DA 4 and non-woven fabrics could be easily recycled through this process. The basic properties of the recycled non-woven fabric remained unchanged and the recycled WPU-DMG 4 -DA 4 resin could be reused. Therefore, the WPU-DMG 4 -DA 4 resin has broad application prospects in the tanning industry.
危险品化学品经营许可证（带存储）