Catalytic Degradation of a Multifunctional Cycloaliphatic Epoxy Matrix and Performance Research of Recovered Carbon Fibers

Chemical recycling represents a promising strategy for recovering fiber-reinforced composites. However, its broader application is hindered by an incomplete understanding of fundamental degradation mechanisms. This study examined the thermal degradation behavior of a typical epoxy matrix. It was revealed that the high electronegativity of oxygen atoms induced preferential cleavage of adjacent chemical bonds, which made them the key initiation sites for the degradation. On the basis of this characteristic, 2-chlorobenzoyl chloride was selected as a catalyst. Under this catalytic system, complete resin degradation was achieved through the rapid cleavage of C–O bonds, significantly lowering the reaction temperature and reducing energy consumption. The catalytic mechanism was elucidated by analyzing the reaction pathway and transition states. Reaction kinetics studies based on the ReaxFF force field further confirmed a notable increase in the generation rate of typical molecules and validated the catalytic efficiency. Additionally, when applied to two other resin systems, this catalytic system also demonstrated excellent degradation performance. Moreover, the recovered carbon fibers showed minimal surface damage and retained over 95% of their single-filament tensile strength and interfacial properties. This approach provides a versatile strategy for developing targeted catalytic degradation systems for different resin matrixes.