Carbon-fiber-reinforced polymers (CFRPs) offer improved energy efficiency in aerospace and automobile applications due to lightweight and mechanical robustness but face challenges with limited recyclability and frequent fiber-polymer delamination caused by inadequate interfacial adhesion. Here, we report an effective design of tough and closed-loop recyclable carbon-fiber-reinforced vitrimers (CFRVs) with exceptional interfacial adhesion through the synergy of a boronic ester-modified commodity polymer, multidiol cross-linker, and diol-functionalized carbon fibers (CFs). The dynamic covalent bonding between the vitrimer and fiber interface results in 43% higher interfacial adhesion than that of CFRVs with pristine CFs. Moreover, CFRVs with diol-CFs exhibit ∼731-MPa tensile strength, 26% higher than unmodified CFRVs and 49% higher than conventional epoxy CFRPs. Importantly, the dynamic boronic ester exchange enables CFRV closed-loop recyclability, repairability, fast thermoformability, self-adhesion, and multicycle processability without compromising mechanical performance. The designed dynamic fiber-matrix interaction will open up a new paradigm of multifunctional CFRPs while providing a path toward closed-loop structural materials.

中文翻译：

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坚韧且可回收的碳纤维复合材料，通过定制的 vitrimer-纤维界面具有出色的界面粘合力

碳纤维增强聚合物（CFRP）由于重量轻且机械强度高，在航空航天和汽车应用中提高了能源效率，但面临着可回收性有限以及由于界面粘合力不足导致纤维-聚合物频繁分层的挑战。在这里，我们报告了一种坚韧且闭环的可回收碳纤维增强玻璃体（CFRV）的有效设计，通过硼酸酯改性商品聚合物、多二醇交联剂和二醇功能化碳纤维的协同作用，具有出色的界面粘合力（CF）。 vitrimer 和纤维界面之间的动态共价键合导致界面粘附力比 CFRV 与原始 CF 的界面粘附力高 43%。此外，含有二醇-CF的CFRV表现出～731-MPa的拉伸强度，比未改性的CFRV高26％，比传统环氧CFRP高49％。重要的是，动态硼酯交换使 CFRV 具有闭环可回收性、可修复性、快速热成型性、自粘合性和多周期加工性，而不会影响机械性能。设计的动态纤维-基体相互作用将开辟多功能CFRP的新范例，同时为闭环结构材料提供一条道路。