Method for preparing single-component high-solid content water-based polyurethane adhesive

The invention discloses a method for preparing a single-component high-solid content water-based polyurethane adhesive, which comprises the following steps of: reacting polyester polyol with a hydrophilic extended chain agent with diisocyanate to generate a performed polymer of -NCO terminal groups; adding polyalcohol monomers to further extend a chain; extending the chain with micromolecular polyalcohol; neutralizing reaction liquid with triethylamine until a pH value of the reaction liquid is 6 to 7, adding a solvent acetone accounting for 5 to 20 percent of the mass of the polyester polyol to adjust viscosity and rapidly dispersing the acetone into nattier blue semitransparent emulsion with de-ionized water; adding a hydrophilic hydroxy urea extended chain agent to finish reaction; and desorbing the solvent acetone to obtain the single-component high-solid content water-based polyurethane adhesive. The single-component water-based polyurethane adhesive prepared by the preparation method of the invention is environmentally-friendly water-based polyurethane emulsion, has the solid content of over 55 percent and high cohesive strength, and can meet the requirement of high-strength bonding without modification.