Thermally responsive self-healing composites with continuous carbon fiber reinforcement

Abtract Continuous carbon fiber composites with self-healing properties are developed using novel thermally responsive healable polyurethanes that incorporate Diels–Alder cycloaddition adducts. Short beam shear testing, which generates delamination inside the composite panels, is conducted to evaluate the healing efficiency. This testing shows that both the composites are stable and that they can be repeatedly healed, achieving average healing efficiencies of ∼85% for the first healing cycle and ∼73% for the second cycle. The results demonstrate that the intrinsic properties of the composites can be maintained after healing has occurred and since the healing ability of the material is only a function of the DA moieties in the polymer matrix, the carbon fiber does not require any treatments.