▎ 摘　　要

NOVELTY - Preparing stable graphene oxide composite film comprises e.g. preparing graphene oxide, preparing graphene oxide mixed film base film by e.g. adding graphene oxide to the solvent for ultrasonic dispersion to obtain uniform graphene oxide dispersion, adding polymer substrate and additives, stirring for 24-48 hours until completely dissolved, allowing to stand and defoaming to obtain uniform and stable casting film solution, scraping obtained casting film solution to form film, placing into deionized water to be converted into a film for 1-24 hours to remove excess solvent to obtain graphene oxide mixed substarte film as base film, where in the casting film solution, the amount of graphene oxide is 0.1-1 wt.%, polymer substrate is 10-20 wt.%, and additive is 10-20 wt.%, the solvent is N-methylpyrrolidone, N, N-dimethylformamide, or N, N-dimethylacetamide, the polymer substrate is polysulfone, polyethersulfone, polyvinylidene fluoride, or polyacrylonitrile. USE - The method is useful for preparing stable graphene oxide composite film. ADVANTAGE - The method solves the problem of dropping of film layer from organic support layer; and improves structural stability in the alkaline solution. DETAILED DESCRIPTION - Preparing stable graphene oxide composite film comprises (a) preparing graphene oxide, (b) preparing graphene oxide mixed film base film by (1) adding graphene oxide obtained in step (a) to the solvent for ultrasonic dispersion to obtain uniform graphene oxide dispersion, adding polymer substrate and additives, stirring for 24-48 hours until completely dissolved, allowing to stand and defoaming to obtain uniform and stable casting film solution, scraping obtained casting film solution to form film, placing into deionized water to be converted into a film for 1-24 hours to remove excess solvent to obtain graphene oxide mixed substarte film as base film, where in the casting film solution, the amount of graphene oxide is 0.1-1 wt.%, polymer substrate is 10-20 wt.%, and additive is 10-20 wt.%, the solvent is N-methylpyrrolidone, N, N-dimethylformamide, or N, N-dimethylacetamide, the polymer substrate is polysulfone, polyethersulfone, polyvinylidene fluoride, or polyacrylonitrile, and the additive is polyvinylpyrrolidone, polyethylene glycol, or lithium chloride, and (c) preparing graphene oxide composite film by (i) adding graphene oxide obtained in step (a) to deionized water, forming uniform graphene oxide dispersion by ultrasonic dispersion, adding crosslinker solution to mixture to obtain mixed dispersion of graphene oxide and crosslinker, where in the dispersion, the concentration of graphene oxide is 0.02-0.2 g/l, and the concentration of the crosslinking agent is 0.005-0.05 mol/l, the cross-linking agent is 1,4-butanediamine, m-xylylenediamine, and 1,4-bis(3-aminopropyl) piperazine, and (ii) placing base film obtained in step (b) in ultrafiltration cup, filtering dispersion of graphene oxide and cross-linking agent through base film under pressure of 0.1-0.5 MPa to obtain wet graphene oxide composite film, placing wet graphene oxide composite film in electric heating constant temperature drying box and reacting at 40-80 degrees C for 0.5-2 hours to obtain stable graphene oxide composite film.