▎ 摘　　要

NOVELTY - Graphene modified bi-component aqueous polyurethane leather coating agent comprises first component and second component. The first component is composed of 25-55 pts. wt. polyol, 29-45 pts. wt. diisocyanate, 3-15 pts. wt. hydrophilic glycol chain extender, 5-25 pts. wt. diol/triol chain extender, 0.05-1 pt. wt. catalyst, 3-20 pts. wt. neutralizer, 250-450 pts. wt. water, 1-15 pts. wt. graphene and 0.05-3 pts. wt. silane coupling agent. The second component consists of 5-15 pts. wt. curing agent. The polyol is PCL1000, PCL2000, PCL3000, PPG400, PPG1000, PPG2000 and/or PBA3000. The hydrophilic glycol chain extender is dimethylolpropionic acid or dimethylolbutanoic acid. The glycol/triol chain extender is 1,4-butanediol, 1,3-propanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane and/or glycerol. USE - Graphene modified bi-component aqueous polyurethane leather coating agent. ADVANTAGE - The product has good storage stability, water resistance, solvent resistance, good mechanical property and heat-conducting property. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of graphene modified bi-component aqueous polyurethane leather coating agent comprising: (A) vacuum-dehydrating polyol, reacting with diisocyanate in the presence of catalyst and reacting at 60-80 degrees C for 1-3 hours to obtain prepolymer; (B) adding hydrophilic glycol chain extender to prepolymer, reacting for 1-3 hours, adding glycol/triol chain extender and remaining catalyst, heating at 70-85 degrees C, performing polymerization reaction for 2-4 hours, cooling and adding neutralizer and organic solvent for neutralization to obtain polyurethane prepolymer; (C) adding water to polyurethane prepolymer under medium-speed stirring, increasing rotation speed after the water is added and emulsifying to obtain water-containing polyurethane emulsion containing hydroxyl group; (D) mixing graphene with water, adding silane coupling agent, ultrasonically dispersing to obtain graphene dispersion, mixing graphene dispersion with hydroxyl-terminated aqueous polyurethane emulsion to obtain modified aqueous polyurethane emulsion; and (E) mixing modified aqueous polyurethane emulsion with wetting leveling agent and hand feel agent and adding curing agent.