▎ 摘　　要

NOVELTY - Preparing anionic polyurethane/cationically modified graphene complex anticorrosion coating comprises (i) first component prepares nanofillers of cationically modified graphene (a) preparing quaternized graphene oxide, (b) preparing cationic modified graphene by ultrasonically dispersing quaternized graphene oxide and 1-3 pts. wt. hexadecyltrimethylammonium bromide were in deionized water, (ii) second component prepares the anionic polyurethane prepolymer by diisocyanate monomer, polyether polyol, water-based chain extender, catalyst, and small molecule chain extender, evenly mixing, polymerization reaction, and obtaining anionic polyurethane prepolymer, (iii) ultrasonically dispersing cationized modified graphene prepared in deionized water for 2 hours, joining in the prepared polyurethane prepolymer dispersion, and mechanically stirring. USE - The method is useful for preparing anionic polyurethane/cationically modified graphene complex anticorrosion coating. ADVANTAGE - The anionic polyurethane/cationic modified graphene complex coating has strong electrostatic interaction with negatively charged polyurethane prepolymer, good anti-corrosion performance, and has good compactness. DETAILED DESCRIPTION - Preparing anionic polyurethane/cationically modified graphene complex anticorrosion coating comprises (i) first component prepares nanofillers of cationically modified graphene (a) preparing quaternized graphene oxide by adding 1-5 pts. wt. graphene oxide to 100 pts. wt. N,N-dimethylformamide to obtain a uniform graphene oxide suspension, adding 1-3 pts. wt. N,N'-dicyclohexylcarbodiimide and 4-6 pts. wt. 3-dimethylaminopropylamine to the graphene oxide suspension, and stirring the mixture in a water bath at 60℃ for 12 hours, washing the mixture with N,N-dimethylformamide and distilled water, and freeze-drying to remove moisture, adding the dry sample and 8-10 pts. wt. hexyl bromide to 100 pts. wt. dimethyl sulfoxide, and completely reacting under the condition of magnetic stirring at 60℃ for 8 hours, washing the mixture with ethanol and distilled water and centrifuging many times, and lyophilizing to obtain quaternized graphene oxide, (b) preparing cationic modified graphene by ultrasonically dispersing quaternized graphene oxide and 1-3 pts. wt. hexadecyltrimethylammonium bromide were in deionized water, and heating at 60℃, refluxing and condensing for 1 hour, filtering to remove moisture, washing the mixture with deionized water, drying under vacuum and left to stand for 12 hours to remove residual solvent to obtain cationized modified graphene, (ii) second component prepares the anionic polyurethane prepolymer by diisocyanate monomer, polyether polyol, water-based chain extender, catalyst, and small molecule chain extender according to the mass ratio of 100:50-60:4-8:0.1-0.5, 0.5-2, evenly mixing, pouring into a 250 ml three-neck round bottom flask equipped with nitrogen inlet, condenser and mechanical stirrer under the condition of 80℃, stirring and reacting at 250 revolutions per minute (rpm) for 2 hours, processing polymerization reaction, and obtaining an anionic polyurethane prepolymer, where the diisocyanate monomer is isophorone diisocyanate, the polyether polyol is polyether diol, the water-based chain extender is 2,2-bismethylolpropionic acid, and the catalyst is dibutyltin dilaurate, the small molecule chain extender is 1,4 butanediol, (iii) ultrasonically dispersing 1 wt.% of the cationized modified graphene prepared in deionized water for 2 hours, joining in the prepared polyurethane prepolymer dispersion, and mechanically stirring at room temperature for 10 minutes, where the mass ratio of anionic polyurethane prepolymer and cationic modified graphene is 100:1-3.