A series of vitrimers combining dynamic hydrogen and imine bonds was prepared by a reaction between amine-terminated nonisocyanate polyurea oligomers (NIPUrea), terephthalaldehyde, and tris(2-aminoethyl)amine at various equivalent ratios. NIPUrea oligomers of different molecular weights were prepared using an environmentally friendly and sustainable approach, implying transurethane polycondensation technology. The vitrimers prepared possessed different cross-linking densities and exhibited T_g values of around 20 °C, as well as thermal stabilities exceeding 300 °C. They displayed high and tunable mechanical strength and ductility, with Young’s modulus from 1.7 to 26.4 MPa, breaking stress from 7.9 to 12.9 MPa and elongation at break from 147 to 517%. They revealed good solvent resistance except in acidic THF/water solutions, in which they underwent irreversible degradation and solubilization. Most of the materials prepared exhibited excellent self-healing efficiency at room temperature (93 to 107%) and good reprocessability and recyclability after hot pressing.

中文翻译：

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设计不含异氰酸酯的生物基聚脲三聚体，具有动态氢键和亚胺键，具有环境自修复、再加工和回收性能


通过胺封端壬氰酸酯聚脲低聚物 （NIPUrea）、对苯二甲醛和三（2-氨基乙基）胺以不同等效比例反应，制备了一系列结合动态氢和亚胺键的三聚体。采用环保和可持续的方法制备不同分子量的 NIPUrea 低聚物，这意味着跨氨基甲酸乙酯缩聚技术。制备的三聚体具有不同的交联密度，T _g 值约为 20 °C，热稳定性超过 300 °C。 它们表现出高且可调的机械强度和延展性，杨氏模量从 1.7 到 26.4 MPa，断裂应力从 7.9 到 12.9 MPa，断裂伸长率从 147 到 517%。它们显示出良好的耐溶剂性，但在酸性 THF/水溶液中除外，在酸性 THF/水溶液中，它们经历了不可逆的降解和溶解。制备的大多数材料在室温下表现出优异的自修复效率 （93% 至 107%），并在热压后表现出良好的再加工性和可回收性。