Preparation method of waterborne polyurethane heat-sealing adhesive capable of being composted and degraded

The preparation method of the waterborne polyurethane heat-sealing adhesive capable of being composted and degraded comprises the following steps: S1, carrying out esterification reaction on dibasic acid, dihydric alcohol, bio-based multi-carbon alcohol and polyhydroxy organic acid, and then carrying out condensation polymerization reaction to form polyester polyol; s2, polyester polyol and non-aromatic isocyanate are subjected to a reaction to generate a-NCO-terminated prepolymer, then a hydrophilic chain extender is added for a chain extension reaction, after a neutralizer is added to adjust the pH value to be neutral, deionized water is added for stirring, finally, an aqueous solution of organic amine is added for post-chain extension, and the waterborne polyurethane heat-sealing adhesive is obtained. The water-based polyurethane heat-sealing adhesive capable of being composted and degraded, which is prepared by the preparation method of the water-based polyurethane heat-sealing adhesive capable of being c