One-component polyurethane-modified epoxy resin emulsion, and preparation method and use thereof

A method for preparing a one-component polyurethane-modified epoxy resin emulsion, comprising:

• mixing an epoxy resin, a monohydroxy acrylate, a dialkyl maleate, a ketone solvent, an aprotic polar solvent, and a polymerization inhibitor to obtain a mixed solution, wherein an epoxy equivalent of the epoxy resin is greater than or equal to 300 g/eq;
• mixing polyethylene glycol, a polyether diol and/or a polyester diol, a diisocyanate, and an organometallic catalyst to obtain a mixture, and subjecting the mixture to addition polymerization to obtain a polyurethane prepolymer;
• mixing the mixed solution with the polyurethane prepolymer to obtain a mixed system, subjecting the mixed system to an addition reaction to obtain a reaction product, adding water to the reaction product and conducting emulsification, and removing the ketone solvent to obtain a waterborne polyurethane epoxy emulsion;
• and
• mixing the waterborne polyurethane epoxy emulsion with an alkyl diamine to obtain a mixed substance, and subjecting the mixed substance to a Michael addition-ring-opening addition reaction to obtain the one-component polyurethane-modified epoxy resin emulsion.