▎ 摘　　要

NOVELTY - Preparing polymer-dispersed liquid crystals (PDLC) film comprises (i) mixing a liquid crystal and graphene nanoparticles to obtain the first solution, (ii) adding citric acid, 1,8-octanediol, 1,2-propanediol transferring to the round-bottom flask, introducing nitrogen atmosphere, stirring the molten reaction mixture to obtain a specific molecular weight of prepolymer, (iii) dissolving the prepolymer of step (ii) with absolute ethanol, stirring to obtain a second solution, (iv) mixing the first solution and the second solution, stirring, carrying out polymerization reaction. USE - The method is useful for preparing polymer-dispersed liquid crystals(PDLC) film (claimed). ADVANTAGE - The method changes the dielectric property of polymer matrix, enhances the reaction rate of the PDLC and reduces the driving voltage of the PDLC. The size and the thickness of the PDLC film is adjustable. DETAILED DESCRIPTION - Preparing polymer-dispersed liquid crystals (PDLC) film comprises (i) adding a liquid crystal and graphene nanoparticles in the mass ratio of (0.1-20):100, stirring to obtain the first solution, (ii) adding citric acid and 1,8-octanediol in the mass ratio of 1:1, transferring to a round bottom flask, introducing nitrogen, stirring at 120-150 degrees C, where stirring is carried out by using magnetic stirrer, stopping stirring at gel point to obtain a specific molecular weight of prepolymer, or adding citric acid 1,8-octanediol, 1,2-propanediol in the mass ratio of 1:(0.6-0.9):(0.1-0.4), transferring to the round-bottom flask, introducing nitrogen atmosphere, maintaining the temperature at 120-150 degrees C, stirring the molten reaction mixture, stopping stirring at gel point to obtain a specific molecular weight of prepolymer, (iii) dissolving the prepolymer of step (ii) with absolute ethanol, stirring to obtain a second solution of concentration 25-40 wt./vol.%, (iv) mixing the first solution and the second solution according to volume ratio of 100:10-30, stirring to obtain PDLC graphene nanoparticles of the prepolymer mixture, stirring, carrying out polymerization reaction at 60-80 degrees C for 3-7 days until the ethanol is completely evaporated.