Polyurethane (PU) has not only been widely used in the daily lives, but also extensively explored as an important class of the essential polymers for various applications. In recent years, significant efforts have been made on the development of self-healable PU materials that possess high performance, extended lifetime, great reliability, and recyclability. A promising approach is the incorporation of covalent dynamic bonds into the design of PU covalently crosslinked polymers and thermoplastic elastomers that can dissociate and reform indefinitely in response to external stimuli or autonomously. This review summarizes various strategies to synthesize self-healable, reprocessable, and recyclable PU materials integrated with dynamic (reversible) Diels–Alder cycloadduct, disulfide, diselenide, imine, boronic ester, and hindered urea bond. Furthermore, various approaches utilizing the combination of dynamic covalent chemistries with nanofiller surface chemistries are described for the fabrication of dynamic heterogeneous PU composites.

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动态共价聚氨酯网络材料：合成和自愈性

聚氨酯 (PU) 不仅在日常生活中得到了广泛的应用，而且作为各种应用中必不可少的一类重要聚合物也得到了广泛的探索。近年来，人们在开发具有高性能、长寿命、高可靠性和可回收性的自修复聚氨酯材料方面做出了重大努力。一种有前景的方法是将共价动态键结合到 PU 共价交联聚合物和热塑性弹性体的设计中，它们可以响应外部刺激或自主地无限解离和重新形成。本综述总结了合成可自修复、可再加工和可回收的 PU 材料的各种策略，这些 PU 材料与动态（可逆）Diels-Alder 环加合物、二硫化物、二硒化物、亚胺、硼酸酯和受阻尿素键相结合。