▎ 摘　　要

NOVELTY - Preparing graphene-modified bio-based aqueous polyurethane involves adding 35-80ml polypropylene glycol and 10-30g graphene into the container, stirring for 10-20 minutes at a temperature of 40-60 degrees C at 350-600 revolution/minute, adding 10-30ml biomass liquid and 1-10ml isophorone diisocyanate, increasing temperature to 80-90 degrees C for 2-3 hours and decreasing temperature to 72-78 degrees C, adding 1-5g dibutyltin dilaurate, dropwise adding 1-5ml dimethylolpropionic acid and 1-5ml butanediol, keeping temperature at 72-78 degrees C for 1.8-2.2 hours and cooling to 42-48 degrees C, adding 5-10ml triethylamine at 42-48 degrees C for 1-2 hours, and adding 10-50g of deionized water and stirring to obtain graphene-modified bio-based aqueous polyurethane. USE - Method for preparing graphene-modified bio-based aqueous polyurethane used in coatings (claimed). ADVANTAGE - The method provides graphene-modified aqueous polyurethane which is solvent-free, meeting people's needs for environmental protection and decorative functions. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a graphene modified bio-based aqueous polyurethane coating, which comprises A component and B component, where A component comprises water, wetting agent, film-forming aid, titanium dioxide, modified graphene-modified bio-based aqueous polyurethane, thickener and leveling agent, antifoaming agent, antifungal agent and bactericide, heavy calcium and barium sulfate, where B component of the graphene-modified bio-based aqueous polyurethane is an aqueous polyisocyanate curing agent; and (2) a method for preparing graphene-modified bio-based aqueous polyurethane coatings, which involves preparing A component by adding water, wetting agent, film-forming aid, half of the total amount of defoamer and dispersant in the mixing tank, mixing and stirring for 3-5 minutes at 500-800 revolution/minute, adding titanium dioxide, heavy calcium and barium sulfate, and stirring for 15-20 minutes at 1000-1500 revolution/minute, adding modified graphene-modified bio-based aqueous polyurethane, thickener and leveling agent into a stirring tank for 10-15 minutes at 500-800 revolution/minute, and adding remaining half of the antifoaming agent, antifungal agent and bactericide, and stirring for 3-5 minutes at a stirring rate of 300-500 revolution/minute to obtain the A component, and mixing A component and B component according to the mass ratio of 4-6:1 to obtain final product.