▎ 摘　　要

NOVELTY - Composite film comprises sodium alginate, gelatin, oxidized graphene. USE - Composite film used in a food packaging (claimed). ADVANTAGE - The composite film has high potential application value. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing composite film, which involves: (A) mixing the sodium alginate, gelatin and water to prepare a first mixed liquid; (B) mixing the mixed solution with an aqueous graphene oxide solution to prepare a second mixed liquid; and (C) mixing the second mixed solution with an aqueous glycerin solution to obtain a composite film-forming liquid.