▎ 摘　　要

NOVELTY - Preparing graphene oxide modified aqueous closed isocyanate curing agent involves stirring and mixing the weighed graphene oxide, diisocyanate and methyl ethyl ketone to obtain a mixed solution A. The ultrasonic treatment of the mixed solution A is obtained, then heated in the reactor to make it react, and cooled to room temperature to obtain product A. The 10-50 pts. wt. of macromolecular polyol and 0.01-0.1 pts. wt. catalyst is taken to product A, mixed uniformly and then heated up the reaction to obtain graphene oxide modified polyurethane prepolymer B. The 2-8 pts. wt. of hydrophilic chain extender is added to the prepolymer B, and heat-reacted to obtain a graphene oxide modified waterborne polyurethane prepolymer C. The mass fraction of isocyanate groups (NCO) in the prepolymer C obtained, based on the residual NCO content, and taken corresponding portion of the blocking agent and added the blocking agent dropwise. USE - Method for preparing graphene oxide modified aqueous closed isocyanate curing agent. ADVANTAGE - The method enables to prepare graphene oxide modified aqueous closed isocyanate curing agent, that makes possible to add graphene to the anti-corrosion coating system through a simple process of adding a curing agent, and greatly improves the overall performance of the coating. DETAILED DESCRIPTION - Preparing graphene oxide modified aqueous closed isocyanate curing agent involves stirring and mixing the weighed graphene oxide, diisocyanate and methyl ethyl ketone to obtain a mixed solution A. The ultrasonic treatment of the mixed solution A is obtained, then heated in the reactor to make it react, and cooled to room temperature to obtain product A. The 10-50 pts. wt. of macromolecular polyol and 0.01-0.1 pts. wt. catalyst is taken to product A, mixed uniformly and then heated up the reaction to obtain graphene oxide modified polyurethane prepolymer B. The 2-8 pts. wt. of hydrophilic chain extender is added to the prepolymer B, and heat-reacted to obtain a graphene oxide modified waterborne polyurethane prepolymer C. The mass fraction of isocyanate groups (NCO) in the prepolymer C obtained, based on the residual NCO content, and taken corresponding portion of the blocking agent and added the blocking agent dropwise until the content of isocyanate groups remains unchanged to obtain a closed waterborne polyurethane prepolymer D modified by graphene oxide. The graphene oxide modified closed waterborne polyurethane prepolymer D is poured into an emulsification tank, added a neutralizer to perform the neutralization reaction, then added 120-200 pts. wt. of deionized water, and performed high-speed emulsification to obtain closed aqueous polyurethane prepolymer emulsion modified by graphene. The graphene modified closed aqueous polyurethane prepolymer emulsion is removed to remove the methyl ethyl ketone solvent, and finally the graphene oxide modified closed aqueous isocyanate curing agent is finally obtained.