▎ 摘　　要

NOVELTY - Preparation of multifunctional film involves adding manganese sulfate and graphene oxide to deionized water, ultrasonically processing in an ultrasonic cleaning machine for 0.5-2 hours, placing under a magnetic stirrer, stirring at 50-90 degrees C at speed of 300-600 rpm, dripping 0.1-0.2 mol/L potassium permanganate solution to obtain a manganese dioxide/graphene oxide solution, adding solution (C) made of a polyvinyl alcohol powder, a chitosan powder, and glacial acetic acid to the manganese dioxide/graphene oxide solution at 50-90 degrees C, heating to 100-120 degrees C to obtain a solution (E), dripping glycerol to solution (E) at a rate of 0.5-2 mL/seconds, stopping heating to obtain a solution (F), adding absolute ethanol to solution (F) at a rate of 0.5-1 mL/second until the bubbles on liquid surface disappears under stirring at a speed of 20-40 rpm for 10-20 minutes, maintaining still for 20-40 minutes to defoam to obtain a membrane liquid, coating the membrane liquid on a substrate, and drying. USE - Preparation of multifunctional film. ADVANTAGE - The method produces multifunctional film having improved mechanical property with fast degradation rate, improved film formability, permeability moisture-retention property, and degradation even using small amount of chitosan, and without formation of sheet agglomeration and stacking. DETAILED DESCRIPTION - Preparation of multifunctional film involves adding a polyvinyl alcohol powder to distilled water in a ratio of 1 g:(80-85) mL under stirring at 50-90 degrees C and a speed of 300-600 rpm for 10-30 minutes to obtain a solution (A), adding a chitosan powder to solution (A), stirring at 50-90 degrees C at speed of 300-600 rpm for 5-15 minutes to obtain a solution (B), dripping glacial acetic acid to solution (B), stirring at 50-90 degrees C at speed of 300-600 rpm for 5-15 minutes to obtain a solution (C), adding manganese sulfate and graphene oxide to deionized water, ultrasonically processing in an ultrasonic cleaning machine for 0.5-2 hours, placing under a magnetic stirrer, stirring at 50-90 degrees C at speed of 300-600 rpm, dripping 0.1-0.2 mol/L potassium permanganate solution to obtain a manganese dioxide/graphene oxide solution, adding solution (C) to the manganese dioxide/graphene oxide solution at 50-90 degrees C, heating to 100-120 degrees C at a stirring speed of 300-600 rpm for 10-30 minutes to obtain a solution (E), dripping glycerol to solution (E) at a rate of 0.5-2 mL/seconds under stirring at 100-120 degrees C and a speed of 300-600 rpm for 5-15 minutes, stopping heating to obtain a solution (F), adding absolute ethanol to solution (F) at a rate of 0.5-1 mL/second until the bubbles on liquid surface disappears under stirring at a speed of 20-40 rpm for 10-20 minutes, maintaining still for 20-40 minutes to defoam to obtain a membrane liquid, coating the membrane liquid on a substrate, and drying. The mass ratio of polyvinyl alcohol powder and chitosan powder is 1:(0.5-4). The ratio of polyvinyl alcohol powder and glacial acetic acid is 1 g:(5-6) mL. The ratio of deionized water and graphene oxide is (90-110) mL:30 mg. The mass ratio of graphene oxide and manganese sulfate is 1:(8-9). The molar ratio of manganese sulfate and potassium permanganate in the potassium permanganate solution is 3:2. The mass ratio of polyvinyl alcohol powder and graphene oxide in the manganese dioxide/graphene solution is 1:(0.005-0.025). The ratio of polyvinyl alcohol powder and glycerol is 1 g:(8-9) mL.