Method for synthetizing aqueous polyurethane emulsion from package waste PET bottles

The invention relates to a method for synthetizing aqueous polyurethane emulsion from package waste PET bottles. The aqueous polyurethane emulsion comprises the following raw components in parts by weight: 17 parts of isophorone diisocyanate, 32 parts of polypropylene glycol, 3.5 parts of dimethylolpropionic acid, 2.5 parts of waste PET alcoholysate, 5 parts of triethylamine, 7 parts of N-methyl pyrrolidone, 8 parts of acetone, 70 parts of deionized water and 0.5 part of dibutyltin dilaurate. The method disclosed by the invention has the advantages that the waste PET bottles are subjected to alcoholysis to generate waste PET alcoholysate with hydroxyl reaction activity, and the waste PET alcoholysate serves as a small molecule chain extender in the aqueous polyurethane emulsion synthetizing to participate in the chain extension reaction of aqueous polyurethane prepolymer, so that the waste PET alcoholysate is successfully grafted on the aqueous polyurethane molecular chain and the aqueous polyurethane emulsion with excellent performances is synthetized; the increasingly serious environmental pollution problem brought by the waste package polymer PET bottles is solved.