The inclusion of latent catalytic healing agents (CHAs) during layup of fibre-reinforced polymer (FRP) composite specimens yields a functionalised composite material with the capability to self-repair. Strategies for preventing the reaction of CHAs with prepreg resins during curing of the host material are explored.
The inclusion of catalyst as an interleave on the composite mid-plane was found to be detrimental to the fracture toughness of the double cantilever beam (DCB) specimens. A potential application for this effect includes damage redirection, whereby propagating damage is steered into self-healing features. This will be an area of interest for future investigation.
Upon failure of the composite, healing is achieved by addition of a low-viscosity epoxide monomer and heating the material to activate the curing agent. Specimens featuring embedded Sc(OTf)3 healed for 2 hours at 200°C showed a mean recovery in peak load of 79%.