Effects of Nylon 6,6 nanofibrous mats on thermal properties and delamination behaviour of high performance CFRP laminates

Nylon 6,6 electrospun nanofibrous membranes interleaved in Carbon Fibre Reinforced Plastic (CFRP) laminates have been proposed as a means to provide a higher threshold value to delamination on structural sites where composites are more prone to develop such failure. A model, highly crosslinked thus inherently brittle, epoxy matrix was selected for its high Young’s modulus and glass transition temperature exceeding 250 °C. The influence of the Nylon 6,6 nanofibres on the curing behaviour of the matrix and on the thermal and dynamic mechanical properties of the cured resin was investigated. These properties were related to the features of the epoxy resin and of the resin impregnated nanofibrous mat. Finally, the delamination behaviour of two composite laminates interleaved with different thicknesses of Nylon interleaf was studied through Mode I delamination tests. The initial Mode I fracture toughness was increased up to about 50% by the presence of a thin mat interleaf.