Autonomous polymers that report damage prior to loss of function and simultaneously self-heal are highly relevant for preventing catastrophic failures and extending the lifetimes of materials. Here, we demonstrate mechanochromic and thermally reprocessable thermosets that can be used for autonomic damage reporting and self-healing coatings. A mechanochromic molecule, spiropyran (SP), is covalently incorporated into thermoreversible Diels–Alder (DA) cross-linking networks. Mechanical activation of SPs in DA networks is confirmed by computational simulations and mechanical testing. The damaged areas of the polymers change colour, emit fluorescence signals, and completely recover after heat treatment. Because of the thermoreversible covalent networks, these polymers can be recycled up to fifteen times without degrading their mechanical, damage-reporting, or self-healing properties. Our autonomic material systems provide a new way to enhance the lifespans and reliabilities of thermosetting coatings, which also expands the range for practical applications of force-induced chemical reactions in polymers.

在功能丧失之前报告损伤并同时自我修复的自主聚合物与防止灾难性故障和延长材料寿命高度相关。在这里，我们展示了可用于自主损伤报告和自愈涂层的机械变色和热可再加工热固性材料。一种机械变色分子螺吡喃 (SP) 共价结合到热可逆的 Diels-Alder (DA) 交联网络中。DA 网络中 SP 的机械激活通过计算模拟和机械测试得到证实。聚合物的受损区域会变色，发出荧光信号，并在热处理后完全恢复。由于热可逆共价网络，这些聚合物可以循环使用多达 15 次而不会降低其机械性能，损坏报告或自愈特性。我们的自主材料系统为提高热固性涂层的使用寿命和可靠性提供了一种新方法，这也扩大了聚合物中力诱导化学反应的实际应用范围。