Carbon Fiber Reinforced Epoxy Resin Composites with Excellent Recyclable Performance via Dynamic Acylsemicarbazide Moieties

Achieving the recycling of the carbon fiber reinforced epoxy resin composite is of great significance toward pursuing a sustainable and circular economy but remains a challenge due to the infusible and insoluble properties of epoxy resin. In this study, the acylsemicarbazide (ASC) moieties are introduced into the network to obtain the dynamic reversible cross-linked thermoset epoxy resin (EPOXY-ASC). An optimized EPOXY-ASC with a tensile stress of 81.27 MPa and an elongation at break of 13.80% exhibits excellent reprocessing performance due to the dynamic reversibility of ASC moieties. The carbon fiber reinforced polymer composites with the EPOXY-ASC resin were successfully prepared with an interlaminar shear strength of 44.86 MPa and can be fully recycled by a solvolysis method without additional agents. The recycled carbon fiber and resin still maintain the original properties well. This study provides a solution to recycle the CFRP composite, which conforms to a circular economy.