High-performance epoxy nanocomposites via constructing rigid structured interphase with epoxy-rich graphene oxide

Epoxy resins, as the most important thermosetting matrix of carbon fiber reinforced polymer (CFRP) composites, are widely used in the structural field, but the highly intrinsic brittleness of epoxy resins greatly limits their application. Therefore, it is urgent to develop new method to prepare high-performance epoxy composites. In this research, GO riched with rigid short-chain structure epoxy group on its surface was synthesized by chemically grafting dopamine, hexachlorocyclotriphosphazene and glycidol successively. Then the modified nanofillers were incorporated into the epoxy matrix to prepare high-performance nanocomposites. The effect of epoxy-rich GO nanosheets as fillers on mechanical properties of aerospace grade epoxy was studied. The results revealed that the epoxy-rich GO could effectively optimize the performance of epoxy resins owing to forming the rigid structured interphase. The tensile strength and elongation at break of the nanocomposites were up to 113 MPa and 7.6% with 0.075 wt% additives, respectively, which greatly surpassed the value reported by the limited researches on strengthening epoxy with GO and its derivate nanofillers. Therefore, instructive idea and effective method were provided to obtain high-performance polymer nanocomposite matrix in this study.