Cryogenic mechanical properties of graphene oxide/epoxy nanocomposites: Influence of graphene oxide with different oxidation degrees

In this contribution, the impact of graphene oxide (GO) with different oxidation degrees on the cryogenic mechanical properties of GO/epoxy nanocomposites is investigated. GO samples with varied oxidation degrees were prepared using a modified Hummers' method. It was found that GO exhibited better dispersion in the matrix and improved interfacial interactions with epoxy resin as its oxidation degree increased. Resultantly, GO/epoxy nanocomposites showed increased tensile properties at room temperature (RT) and liquid nitrogen temperature (LNT) as GO oxidation degree increased and reached the idealist performance with appropriate GO oxidation degree. Under low GO loading of 0.10 wt% GO/epoxy nanocomposites exhibited the highest tensile strength of 78.0 MPa at RT and 123.2 MPa at LNT, 31% and 14% higher than that of neat epoxy, respectively. Based on the fractured surface investigation, toughening mechanisms of GO for epoxy nanocomposites at RT and LNT were analyzed, between which there existed significant differences.

Automated summary

The study showed that as the oxidation degree of graphene oxide increased, it exhibited better dispersion in the matrix and improved interfacial interactions with epoxy resin, leading to enhanced mechanical properties of the nanocomposites. The tensile properties of the GO/epoxy nanocomposites at room temperature and liquid nitrogen temperature increased with the GO oxidation degree, reaching the highest performance at an appropriate oxidation degree. The toughening mechanisms of GO for epoxy nanocomposites at room temperature and liquid nitrogen temperature were analyzed and showed significant differences.