Ozyigit S., Kachouri O., Bardon J., Ruch D., Laachachi A.
Composites Part A Applied Science and Manufacturing, vol. 204, art. no. 109614, 2026
In this study, the debonding-on-demand approach is employed to recycle carbon fibers from their epoxy matrix composite laminates. The carbon fiber-reinforced epoxy matrix composites are manufactured, in which 20 wt% of an organophosphorus flame retardant is incorporated into the epoxy matrix as a debonding agent. The modified composites remain inert and exhibit good mechanical performance under usage conditions, and debonding agents in the structure of the composite laminates start to activate when the modified composites are exposed to a thermal stimulus, thereby inducing the interply separation of the carbon fiber layers. Subsequently, separated carbon fibers can be either used directly to produce recycled composites by applying new epoxy resin or exposed to an additional oxidative acetic acid-based chemical cleaning method effective in mild conditions to remove the epoxy residues from the surface of the separated layers. Also, the chemically cleaned carbon fibers are reused to manufacture another recycled laminate, and flexural tests are conducted to compare the mechanical performance of the reference, modified, and recycled composites. The mechanical test results obtained on the modified composite demonstrate the suitability of the novel debonding-on-demand approach for the structural composites’ applications together with facilitating the recycling of carbon fiber. The recycling temperature of carbon fibers is lowered while different recycled composites for primary or secondary load-bearing applications are manufactured.
