▎ 摘　　要

NOVELTY - Preparing nanocomposite coating involves placing 15-20 pts. wt. deionized water in a container of a high-speed disperser, and sequentially adding 4-5 pts. wt. modified graphene and 0.5-0.8 pts. wt. wetting and dispersing agent at speed of 300-500 rotation per minute (rpm). The contents are dispersed for 15-20 minutes, rotation speed is increased to 1600-1800 rpm, and the high-speed dispersion is continued for 30-40 minutes to obtain a premix. The rotation speed is adjusted to 300-500 rotation per minute, 30-40 pts. wt. modified acrylate emulsion is added, and the viscosity of coating is adjusted to 80-100 Krebs units with 0.3-0.4 pts. wt. thickener and 0.2-0.3 pts. wt. leveling agent. 0.2-0.3 pts. wt. Antifoaming agent is further added and the mixture is dispersed for 10-12 minutes to obtain nanocomposite coating. USE - Method for preparing nanocomposite coating. ADVANTAGE - The method utilizes modified acrylate emulsion as the polymer matrix of the coating, that is safe, non-toxic, non-combustibile and eco-friendly, and has high thermal stability and hydrophobic property. By modifying graphene as a reinforcing filler, not only can the dispersion performance of graphene in the coating matrix be improved, but also the interfacial adhesion between graphene and the coating matrix can be improved, and the mechanical properties of the layer can be enhanced. By using auxiliary agents, an eco-friendly nanocomposite coating with stable storage and excellent comprehensive performance is obtained. DETAILED DESCRIPTION - Preparing nanocomposite coating involves placing 15-20 pts. wt. deionized water in a container of a high-speed disperser, and sequentially adding 4-5 pts. wt. modified graphene and 0.5-0.8 pts. wt. wetting and dispersing agent at speed of 300-500 rotation per minute (rpm). The contents are dispersed for 15-20 minutes, rotation speed is increased to 1600-1800 rpm, and the high-speed dispersion is continued for 30-40 minutes to obtain a premix. The rotation speed is adjusted to 300-500 rotation per minute, 30-40 pts. wt. modified acrylate emulsion is added, and the viscosity of coating is adjusted to 80-100 Krebs units with 0.3-0.4 pts. wt. thickener and 0.2-0.3 pts. wt. leveling agent. 0.2-0.3 pts. wt. Antifoaming agent is further added and the mixture is dispersed for 10-12 minutes to obtain nanocomposite coating. The modified acrylate emulsion is prepared by adding dehydrated isophorone diisocyanate, polycaprolactone diol, hydrophilic chain extender 2,2-dimethylol butyric acid, internal cross-linking agent trimethylolpropane, and methyl methacrylate, butyl acrylate, methacrylic acid as a solvent to four-necked flask equipped with thermometer, stirrer and reflux condenser. The reaction system is protected by nitrogen, added with a catalyst of dibutyltin dilaurate, and the contents are reacted at 80 degrees C for 2-3 hours. The obtained mixture is added with monohydroxyethyl methacrylate, and triethylamine, neutralized for 20-30 minutes, followed with addition of deionized water to disperse under high speed stirring to obtain a composite emulsion. At 60 degrees C, the hexafluorobutyl acrylate monomer is added dropwise to the composite emulsion at a rate of 0.5 drops/second, and the hydrogen peroxide and ferrous chloride solutions are simultaneously added dropwise immediately after the dropwise addition. After the completion of the dropwise addition, the reaction is carried out under the constant temperature of 60 degrees C for 4 hour, and the mixture is heated at 60 degrees C for 1 hour, and then discharged to obtain a modified acrylate emulsion.