Polyether-type water-based polyurethane emulsion and preparation method thereof

The invention discloses a polyether-type water-based polyurethane emulsion and a preparation method thereof. The method comprises the following steps: 1) in an inert atmosphere, mixing a chain extender with diisocyanurate, and reacting to obtain a mixture I; 2) in an inert atmosphere, mixing the mixture I with polyether glycol and a hydrophilic chain extender, and reacting to obtain a mixture II; 3) mixing the mixture II with hydroxyacrylate, reacting to obtain a polyurethane prepolymer; and 4) neutralizing the polyurethane prepolymer by adding alkali, adding water, emulsifying, and carrying out radiation crosslinking to obtain the polyether-type water-based polyurethane emulsion. The micromolecule diol and diisocyanate are prepolymerized, the chain segment formed by reaction with polyether chain segment has lower phase reversal difficulty than the polyether prepolymer in the emulsifying process, and the emulsion process can be easily completed when the molecular weight is lower. The Co-60-gamma ray is utilized to perform irradiation crosslinking on the emulsion obtained from the polyurethane prepolymer, thereby effectively enhancing the molecular weight of the water-based polyurethane; and thus, the water-based polyurethane emulsion has high solid content and favorable mechanical properties.