▎ 摘　　要

NOVELTY - Preparing aqueous flame-retardant self-healing polyurethane based on modified graphene comprises reacting amino cyclotriphosphazene and 4-dimethylaminopyridine at room temperature for 12-24 hours under nitrogen, centrifuging and drying to obtain nitrogen-phosphorus modified graphene oxide, adding isocyanate-based silane, and reacting, performing ultrasonic pulverization for 4-8 hours, adding modified nano-graphene oxide with nitrogen, phosphorus and silicon, polymer diol, hydrophilic chain extender, and dibutyltin dilaurate into a three-necked flask with a stirring device under the protection of nitrogen, adding diselenide for end capping, obtaining isophorone diamine-terminated aqueous self-healing polyurethane containing double selenium bonds, mixing the aqueous self-healing polyurethane modified nitrogen-phospho-silicon modified nano-graphene oxide and aqueous self-healing polyurethane containing double selenium bonds. USE - The method is useful for preparing aqueous flame-retardant self-healing polyurethane based on modified grapheme for leather finishing and fabric finishing. ADVANTAGE - The method is environmentally friendly. The prepared material has high mechanical property and excellent flame-retardant self-repairing function. DETAILED DESCRIPTION - Preparing aqueous flame-retardant self-healing polyurethane based on modified graphene, where the aqueous flame-retardant self-healing polyurethane comprises aqueous self-healing polyurethane modified nitrogen, phosphorus and silicon modified nano-graphene oxide and aqueous self-healing polyurethane containing double selenium bonds, and raw material comprises 4.5-13.5 pts. wt. graphene oxide, 0.1-0.34 pts. wt. amino cyclotriphosphazene, 0.01-0.02 pts. wt. 4-dimethylaminopyridine, 0.1-0.3 pts. wt. isocyanato silane, 22.5-67.5 pts. wt. polymer diol, 13.5-22.5 pts. wt. diisocyanate, 1.4-4 pts. wt. hydrophilic chain extender, 0.01-0.02 pts. wt. dibutyltin dilaurate, 2.8-6.3 pts. wt. diselenide, 1.4-3.5 pts. wt. triethylamine, 200-400 pts. wt. deionized water and 7-14 pts. wt. isophorone diamine. The method comprise placing the graphene oxide aqueous dispersion of 1 mg/ml in a single-necked flask containing a magnetic stir bar, and reacting amino cyclotriphosphazene and 4-dimethylaminopyridine at room temperature for 12-24 hours under nitrogen, centrifuging and drying to obtain nitrogen-phosphorus modified graphene oxide, dispersing nitrogen-phosphorus-modified graphene oxide in an organic solvent of 8-12 times the quality of nitrogen-phosphorus-modified graphene oxide, adding isocyanate-based silane, and reacting at 65-85 degrees C for 24-48 hours under the protection of nitrogen, using an ultrasonic cell pulverizer at room temperature and performing ultrasonic pulverization for 4-8 hours, centrifugally drying to obtain nitrogen, phosphorus and silicon modified nano-graphene oxide with a particle size of less than 100 nm, drying the three-necked flask, stirrer, feeding tube and other instruments at 100-110 degrees C for 1-3 hours, placing in a desiccator to fully cooling, adding modified nano-graphene oxide with nitrogen, phosphorus and silicon, polymer diol, hydrophilic chain extender, and dibutyltin dilaurate into a three-necked flask with a stirring device under the protection of nitrogen, fully dispersing by the organic solvent with 1-3 times, stirring and adding the diisocyanate and adding under the protection of nitrogen at 75-85 degrees C, and reacting for 2-3 hours, cooling to 50-60 degrees C, adding diselenide for end capping, reacting for 3.5-5.5 hours under nitrogen protection, and cooling to 35-45 degrees C and adding triethylamine for neutralization for 25-45 minutes, using a high-speed mixer to shear and emulsify at 1200-1800 revolutions/minutes, and adding nitrogen-phosphosilicon modified nano-graphene oxide, polymer diol, hydrophilic chain extender, dibutyltin dilaurate, diisocyanate, diselenide and triethylamine 3-4 times the total mass of deionized water, emulsifying for 30-50 minutes, removing the organic solvent under reduced pressure at 40 degrees C and 0.09MPa, obtaining diselendiol-terminated aqeuousself-healing polyurethane modified nitrogen phosphorus silicon modified nano-graphene oxide, adding the polymer diol, hydrophilic chain extender, and dibutyltin dilaurate into a three-necked flask with a stirring device, stirring and adding diisocyanate under the protection of nitrogen at 75-85 degrees C, and reacting 2-3 hours, cooling down to 50-60 degrees C, adding diselenide to extend the chain, reacting under nitrogen protection for 3.5-5.5 hours, cooling to 35-45 degrees C and adding triethylamine for neutralization for 25-45 minutes, shearing in high-speed mixer and emulsifying at 1200-1800 revolutions/minute, and adding the aforementioned raw materials 3-4 times the total mass of deionized water and isophorone diamine, emulsifying for 30-50 minutes, obtaining isophorone diamine-terminated aqueous self-healing polyurethane containing double selenium bonds, mixing the aqueous self-healing polyurethane modified nitrogen-phospho-silicon modified nano-graphene oxide and the aqueous self-healing polyurethane containing double selenium bonds at a mass ratio of 5:95-15:85, and stirring at 500-1000 revolutions/minutes for 2-3 hours to obtain final product.