▎ 摘　　要

NOVELTY - Conductive composite film comprises reduced graphene oxide, quaternary ammonium salt hemicellulose and chitosan. USE - Used as conductive composite film. ADVANTAGE - The composite film: has high strength, good heat resistance and electrical conductivity; and preparation method is simple, economical and environmentally-friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing conductive composite film, comprising (i) adding natural graphite powder and sodium nitrate into concentrated sulfuric acid, stirring for 1 hours in an ice bath at 0 degrees C, reacting, adding potassium permanganate slowly, transferring the system into an oil bath, maintaining the temperature at 30-40 degrees C, reacting for 30 minutes, adding slowly deionized water, maintaining the temperature at 85-95 degrees C, reacting for 15 minutes, adding deionized water, hydrogen peroxide, and hydrochloric acid, washing, filtering, dialyzing and freeze-drying to obtain a graphene oxide sample, adding the graphene oxide sample into deionized water, adjusting the concentration to 0.01%, reacting the graphene oxide suspension with the reducing agent L-ascorbic acid in a water bath at 95 degrees C, adjusting the pH of the dispersion to 9-10 with a 25% aqueous ammonia solution, reacting for 15 minutes to obtain a reduced graphene oxide suspension and subjecting the obtained suspension to ultrasonic treatment with an ultrasonic crusher to obtain a reduced graphene oxide dispersion; (ii) preparing the quaternary ammonium salt hemicellulose, chitosan and epichlorohydrin into a solution and reacting at 60 degrees C for 1-3 hours; and (iii) mixing the reduced graphene oxide dispersion with the composite solution, stirring the mixture and air-drying.