▎ 摘　　要

NOVELTY - Preparing graphene-modified aqueous polyurethane, comprises e.g. (i) adding graphene oxide into deionized water, dispersing to obtain first mixed solution, sending first mixed solution into an ultrasonic device, continuously dispersing, sequentially adding 3-aminopropyltriethoxysilane and acetic acid, reacting, finally sending first mixed solution into ultrasonic device and dispersing to obtain 0.9-1.1 wt.% graphene oxide chain extender, and (ii) adding macromolecular diol, small molecular diol, diisocyanate and catalyst into a reaction container, reacting to obtain second mixed solution, adding small molecular hydrophilic compound into the second mixed solution, reacting, cooling second mixed solution, adding neutralizing agent, continuously reacting, cooling second mixed solution, adding deionized water, sending into a stirrer, stirring, dropwise adding graphene chain extender into second mixed solution, continuously stirring and distilling to obtain final product. USE - The graphene-modified aqueous polyurethane is useful in preparing graphene oxide/aqueous polyurethane paint for automobile cushion leather (claimed). ADVANTAGE - The method: utilizes graphene oxide to modify aqueous polyurethane; and increases compatibility of polyurethane and graphene. The graphene oxide/aqueous polyurethane paint: has excellent wear-resistance property; solves the problem of poor wear resistance of automobile cushion leather coating material; and improves wear resistance of automobile cushion leather coating material.. DETAILED DESCRIPTION - Preparing graphene-modified aqueous polyurethane, comprises (i) adding graphene oxide into deionized water, dispersing at high speed for 60-120 minutes to obtain first mixed solution, sending first mixed solution into an ultrasonic device, continuously dispersing for 30-60 minutes, sequentially adding 3-aminopropyltriethoxysilane and acetic acid, reacting at 60-80 degrees C for 5-8 hours, finally sending first mixed solution into ultrasonic device and dispersing for 24-36 hours to obtain 0.9-1.1 wt.% graphene oxide chain extender, where the weight ratio between graphene oxide, deionized water, 3-aminopropyltriethoxysilane and acetic acid is 1:100:0.01-0.05:0.1-0.2, the working power of the ultrasonic device is 0.50-1.50 kW and the working frequency is 25-40 kHz, and (ii) adding macromolecular diol, small molecular diol, diisocyanate and catalyst into a reaction container, reacting at 60-90 degrees C for 3-4 hours to obtain second mixed solution, adding small molecular hydrophilic compound into the second mixed solution, reacting for 1-2 hours, cooling second mixed solution to 20-30 degrees C, adding neutralizing agent, continuously reacting for 0.5-1 hour, cooling second mixed solution to 5-10 degrees C, adding deionized water, sending into a stirrer, stirring for 3-5 minutes, dropwise adding graphene chain extender into second mixed solution, continuously stirring for 30 minutes and distilling to obtain final product having a solid content of 20-40 wt.%, where the weight ratio between macromolecular diol, small molecular diol, diisocyanate, catalyst, small molecular hydrophilic compound, neutralizing agent, deionized water and graphene oxide chain extender is 30-90:2-10:20-50:0.2-0.4:1-6:0.5-5:100-300:30-70 and the working rotating speed of the stirrer is 2500-3000 revolutions/minute. INDEPENDENT CLAIMS are also included for: (1) graphene-modified aqueous polyurethane, obtained by above mentioned method; (2) use of graphene-modified aqueous polyurethane in preparing graphene oxide/aqueous polyurethane paint for automobile cushion leather. The graphene oxide/aqueous polyurethane paint is prepared by adding graphene oxide into deionized water, dispersing at high speed for 60-120 minutes to obtain mixed solution, sending mixed solution into an ultrasonic device, continuously dispersing for 30-60 minutes, sequentially adding silane coupling agent and acetic acid, reacting at 60-80 degrees C for 5-8 hours, sending mixed solution into the ultrasonic device and dispersing for 24-36 hours to obtain 0.9-1.1 wt.% graphene oxide dispersion, where the weight ratio between graphene oxide, deionized water, silane coupling agent and acetic acid is 1:100:0.01-0.05:0.1-0.2, the working power of the ultrasonic device is 0.50-1.50 kW and the working frequency is 25-40 kHz, blending graphene oxide dispersion, graphene-modified aqueous polyurethane, dispersant, thickening agent, antifoaming agent, flatting agent, hand-feeling agent and matting agent, dispersing at high speed for 4-5 hours, sending into the ultrasonic device, continuously dispersing for 1-3 hours and filtering to obtain final product having a fineness of less than 80 mu m, where the weight ratio between graphene oxide dispersion, graphene-modified aqueous polyurethane, dispersant, thickening agent, antifoaming agent, flatting agent, hand-feeling agent and matting agent is 5-20:30-70:0-5:0-5:0-5:0-5:0-5:0-5; and (3) graphene oxide/aqueous polyurethane paint, obtained by above mentioned method.