Improved interlaminar property of carbon fiber/epoxy composites with polyurethane/RGO core-shell structure fibrous mat

Interlaminar delamination is the most common failure mode of carbon fiber reinforced epoxy (CF/EP) composites, which severely limits their practical application. In this work, reduced graphene oxide (RGO) was decorated on electrospun polyurethane (PU) fibrous veil to produce a hybrid core-shell structure fibrous mat, which was integrated into CF/EP to thoroughly evaluate their influence on the interlaminar fracture toughness and interlaminar shear strength of laminates. The results show that, compared to those of plain composite, the mode I and II interlaminar fracture toughness of the PU/RGO interleaved composites increases by 170 % and 21 %, respectively, while their interlaminar shear strength synchronously increases by 14 %. The improved fracture toughness could be attributed to the plastic deformation of PU and epoxy mixture, crack deflection caused by RGO and pull out and separation behavior of RGO, etc. Henceforth, our hybrid interleaf can be considered as a promising candidate for designing high delamination resistance composites for structural applications.