Preparation and characterization of ambient self cross-linkable epoxy nano emulsion modified by ketone and hydrazine

Epoxy laurate was synthesized from epoxy resin E-20, and then modified by grafting with acrylic acid monomer and diacetone acrylamide(DAAM), while by adding adipic acid dihydrazide(ADH), to prepare a ketone and hydrazine self-cross-linking at room temperature nano epoxy resin emulsion. The structure of the products synthesized in each step and the emulsion after curing were characterized with infrared spectroscopy, which proved that the design resin structure was obtained. FTIR spectrum of the film of the emulsion showed that hydrazone was produced by ketone reaction with hydrazide. The glass transition temperature(Tg) of the resin was studied with DSC analysis. The synthetic resin had two Tg, the Tg of acrylic acid graft epoxy resin and the Tg of pure acrylic resin, respectively, and the Tg of acrylic acid graft epoxy resin was lower than room temperature, indicating that self-cross-linking reaction could occur at room temperature. The ratio of functional monomer was investigated with particle size analysis and integrated performance analysis during the synthesis process of the modified epoxy resin emulsion. When mass ratio of E-20 and MAA was 11.0%~14.7%, the amount of DAAM was 2%~3%, and m(ADH)/m(DAAM) was 0.8~1.0, good emulsion storage stability and film properties were obtained. The morphology and particle size of the emulsion were studied with transmission electron microscopy and particle size analysis, showing that particle size of emulsion was about 88 nm, and particle size distribution was uniform, existing substantially as stable spherical structure. Test results proved that the anti-corrosion coatings prepared from the nano epoxy emulsion showed good comprehensive performance.