▎ 摘　　要

NOVELTY - Graphene oxide is dissolved in solvent. Ethanolamine is added to mixture and heated, to obtain graphene oxide. Graphene oxide is dissolved in solvent, to obtain graphene oxide solution. Macropolyol is added to graphene oxide solution. Polyisocyanate is added to mixture and heated. Hydrophilic chain extender is added to polyurethane prepolymer (a1) and reacted. Diol, polyol and catalyst are added to mixture and reacted, to obtain graphene aqueous polyurethane prepolymer (a2). The polyurethane prepolymer (a2) is neutralized and emulsified, to obtain aqueous polyurethane latex. USE - Preparation of cationic low-modulus high-strength aqueous polyurethane latex used for ultra-thin high-powered condom, leather aqueous processing agent and material for aqueous adhesive. ADVANTAGE - The method enables preparation of cationic aqueous polyurethane latex with high film strength and low modulus by simple method. DETAILED DESCRIPTION - 10-100 mg Graphene oxide is dissolved in 100 ml polar solvent and ultrasonically processed for 30 minutes, to obtain uniform dispersion. 0.1-1 g Ethanolamine is added to mixture, heated at 50-90 degrees C under reflux for 24 hours, cooled to room temperature, washed with water or acetone until nearly neutral and dried under vacuum, to obtain ethanolamine-functionalized graphene oxide. 100-500 mg Ethanolamine-functionalized graphene oxide is dissolved in 5-10 ml aprotic solvent, to obtain ethanolamine-functionalized graphene oxide solution. 10-80 g Macropolyol is added to ethanolamine-functionalized graphene oxide solution. 10-80 g Polyisocyanate is added to mixture, evenly heated and reacted at 80-90 degrees C for 1-5 hours, to obtain graphene polyurethane prepolymer (a1). Graphene polyurethane prepolymer (a1) is vacuum dehydrated under dry nitrogen protection. 1-10 g Hydrophilic chain extender is added to graphene polyurethane prepolymer (a1) and reacted at 50-70 degrees C for 1 hour. 0-15 g Small molecule diol, 0-10 g small molecule polyol, 0-0.5 g catalyst and 20-100 ml aprotic solvent are added to mixture, reacted at 50-70 degrees C for 3-8 hours, cooled to 20-40 degrees C and discharged, to obtain graphene aqueous polyurethane prepolymer (a2). The graphene aqueous polyurethane prepolymer (a2) is added to emulsion barrel, and 2-10 ml mixture is neutralized for 1 minute. 150-300 ml Water is added to mixture, high-speed mixed and emulsified, to obtain cationic low-modulus high-strength aqueous polyurethane latex. The neutralizing agent comprises acetic acid.