基于肟氨键和二硫键的室温自修复聚氨酯弹性体的制备及性能

Preparation and properties of room temperature self-healing polyurethane elastomer based on oxime and disulfide bonds

摘要:

以对苯二甲醛和盐酸羟胺为原料，合成了对苯二甲醛二肟，将合成的二肟和双(4-羟苯基)二硫醚、聚四氢呋喃醚、二醇异佛尔酮二异氰酸酯反应，制备了一系列多种动态键协同作用的自愈合聚氨酯（SPPU）。通过1HNMR、FTIR 对合成的对苯二甲醛二肟和SPPU进行了表征，证明了具有肟键和芳香二硫键的自修复聚氨酯被成功合成。采用划痕测试和愈合测试对SPPU自愈合能力进行了评价；采用量子化学计算聚氨酯中两种氢键的键能，并对自修复原理进行讨论。结果表明，在一系列聚氨酯弹性体中SPPU-3中肟键和二硫键分别占到扩链剂的一半，表现出最佳的综合性能，在室温下愈合2 h 后，划痕几乎完全消失，室温下愈合48 h 后，聚氨酯的自愈率可以达到93.78 %。

Abstract:

A series of multiple dynamic bond synergies base self-healing polyurethanes (SPPU) were synthesized via reaction of terephthalaldoxime, which was prepared from hydroxylamine hydrochloride and terephthalaldehyde, with polytetrahydrofuranediol, isophorone diisocyanate and bis(4-hydroxyphenyl) disulfide. Characterization of the synthesized benzaldehyde dioxime and SPPU was conducted using 1H NMR and FTIR, confirming the synthesis of self-healing polyurethane containing oxime and aromatic disulfide bonds. Evaluation of SPPU self-healing capability was performed through scratch and healing tests. Quantum chemistry calculations were employed to determine the bond energies of the two types of hydrogen bonds in the polyurethane, and a discussion on the principles of self-healing ensued. The findings revealed that in a series of polyurethane elastomers, SPPU-3 exhibited the optimal comprehensive performance, with oxime and disulfide bonds each comprising half of the chain extender. After 2 hours of healing at room temperature, scratches nearly vanished, and after 48 hours of healing at the same temperature, the polyurethane achieved a self-healing rate of 93.78%.