Improvement of curing reaction activity of one-component room temperature-curable epoxy adhesive by the addition of functionalized graphene oxide

Functionalized graphene oxide (GO) nanocomposites including GO-Fe and GO-Fe-P were prepared and used as a curing additive for a one-component room temperature-curable epoxy adhesive (OCRTCEA). The results showed that the functionalized GO nanocomposites were conducive to accelerating the curing reaction of OCRTCEA with a moisture-activated ketimine as a latent curing agent, and when OCRTCEA containing 1 wt% GO-Fe-P was exposed to air at room temperature for 24 h, its lap shear strength reached 11.2 MPa, which was 144% higher than that of pure OCRTCEA under the same test conditions. Furthermore, the storage stability of OCRTCEA containing 1 wt% GO-Fe-P was similar with that of pure OCRTCEA over 60 days of storage. The enhanced curing reaction activity of OCRTCEA might be due to the role of curing accelerator of GO nanocomposites, the enhanced polarity of OCRTCEA because of the addition of GO nanocomposites, and the special morphology of GO nanocomposites.