A thermadapt epoxy based on borate ester crosslinking and its carbon fiber composite as rapidly processable prepreg

Introduction of the dynamic bonds will endow the polymer architectures with attractive adaptive properties, which enable thermoset materials re-processable, recyclable and sustainable. However, exploration of the miscible and cost-effective moieties containing such dynamic fragments are the burning question to implement the reversible polymer on a mass basis. Here we report an indirect formation strategy of borate ester crosslinkage from commercially available feedstocks. Remarkably, the borate ester crosslinks are ingeniously generated from borate and diols which are formed in-situ by glycidol and amines. The good miscibility of the precursors could be achieved without the use of any solvent, which benefits the large-scale production and practical application of these promising adaptive thermoset polymers. Such thermadapt epoxy networks utilizing dynamic borate ester crosslinking exhibit adaptive properties such as reprocessing, welding, self-healing, and extrusion injection molding. In addition, the facile reprocess and remold processes of resulted carbon fiber composite are demonstrated by incorporating thermadapt epoxy resin with continuous carbon fiber sheets. Our synthetic strategy provides innovative insights as a green and sustainable solution to traditional thermosets and its composites.