▎ 摘　　要

A different sequence of epoxy composite preparation was performed by mixing oxidized graphene platelets (oGNP) with a curing agent prior to mixing it with epoxy resin. When oGNP was mixed with trimethylhexamethylene diamine (TMD), the condensation reaction between the hydroxyl and amine groups resulted in the formation of a TMD/oGNP colloid. The TMD/oGNP colloid was used to cure epoxy resin. The colloidization eventually improved the dispersion and prevented re-agglomeration in the epoxy resin. A thermogravimetric analysis showed that the thermal stability of the epoxy/oGNP system had improved, while the presence of the oGNP gave more stability to the solvent in terms of an increase in the crosslink density. These results showed that the TMD/oGNP colloid sequence was better able to enhance the properties of the epoxy composite compared to the conventional method of obtaining epoxy/graphene by mixing the graphene with the epoxy resin prior to adding in the curing agent. (C) 2017 Elsevier Ltd. All rights reserved.