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-DMG₄-DA₄ 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-DMG₄-DA₄ 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-DMG₄-DA₄ 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-DMG₄-DA₄ 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-DMG₄-DA₄ resin could be reused. Therefore, the WPU-DMG₄-DA₄ resin has broad application prospects in the tanning industry.

最近，水性聚氨酯（WPU）的自愈性和可回收性引起了广泛的研究关注。在此，使用不同重量比的狄尔斯-阿尔德 (DA) 二醇和二乙酰肟 (DMG) 作为与聚四亚甲基醚二醇 (PTMG)、异佛尔酮二异氰酸酯 (IPDI) 和二羟甲基丙酸 (DMPA) 的反应单体。基于肟-氨基甲酸酯和 DA 键的协同动态反应，制备了一系列热驱动自修复和绿色可回收水性聚氨酯薄膜 (WPU-DMG _x -DA _{y )。我们研究了 WPU-DMG x} -DA _y的特性通过粒径和zeta电位测试对乳液进行了测试，结果表明这些乳液具有优异的储存稳定性。通过动态力学分析确定了WPU-DMG _x -DA _y薄膜的自愈性能。结果表明，WPU-DMG ₄ -DA ₄薄膜具有最好的自愈能力，在120 ℃自愈4 h后自愈效率可达92. ± 0.1 %。通过傅里叶变换红外光谱研究了自愈行为的机理，并验证了肟-氨基甲酸酯和 DA 键的有效可逆性。此外，热重分析和拉伸测试结果表明，WPU-DMG _{x的热稳定性和机械性能}-DA _y薄膜得到显着改善。更重要的是，WPU-DMG ₄ -DA ₄薄膜可以在室温下溶解在丙酮/乙醇混合溶剂中。回收的聚氨酯溶液可再次分散于水中得到水性聚氨酯乳液。_{回收3次后，WPU-DMG 4} -DA ₄薄膜的力学性能恢复效率高于90.1 ± 0.1 %，回收薄膜保持热稳定性和自修复行为。_{另外，WPU-DMG 4} -DA ₄复合得到的合成革通过这个过程，无纺布可以很容易地回收利用。回收无纺布的基本性能保持不变，回收的WPU-DMG ₄ -DA ₄树脂可以重复使用。因此，WPU-DMG ₄ -DA ₄树脂在制革行业具有广阔的应用前景。