▎ 摘　　要

NOVELTY - Preparing sandwich chitosan-based antibacterial composite film with reduced graphene oxide immobilized nano-silver involves washing, drying, pulverizing, and ball milling the corn stalks to obtain corn stalk powder. The corn stalk powder is dissolved in sodium hydroxide/urea system using low-temperature freeze-thaw method to obtain corn stalk solution. The silver ammonia solution is added to the graphene oxide solution and mixed uniformly to obtain graphene oxide/silver ammonia mixed solution. The corn stalk solution is added to the graphene oxide/silver ammonia mixed solution to obtain reaction solution. The reduction reaction is performed under microwave assisted conditions to obtain reduced graphene oxide/nano silver solution. The glycerin is added dropwise to the chitosan solution to obtain glycerin/chitosan mixture. USE - Method for preparing sandwich chitosan-based antibacterial composite film with reduced graphene oxide immobilized nano-silver for food packaging (claimed). ADVANTAGE - The method enables to prepare sandwich chitosan-based antibacterial composite film with reduced graphene oxide immobilized nano-silver that achieves the effect of long-lasting and slow release, and avoids the problem of cumulative toxicity in food packaging applications. DETAILED DESCRIPTION - Preparing sandwich chitosan-based antibacterial composite film with reduced graphene oxide immobilized nano-silver involve washing, drying, pulverizing, and ball milling the corn stalks to obtain corn stalk powder. The corn stalk powder is dissolved in sodium hydroxide/urea system using low-temperature freeze-thaw method to obtain corn stalk solution. The silver ammonia solution is added to the graphene oxide solution and mixed uniformly to obtain graphene oxide/silver ammonia mixed solution. The corn stalk solution is added to the graphene oxide/silver ammonia mixed solution to obtain reaction solution. The reduction reaction is performed under microwave assisted conditions to obtain reduced graphene oxide/nano silver solution. The glycerin is added dropwise to the chitosan solution to obtain glycerin/chitosan mixture. The reduced graphene oxide/nanosilver solution and glycerin/chitosan mixture are self-assembled layer by layer through electrostatic interaction to obtain sandwich chitosan-based antibacterial composite film with nano silver immobilized on reduced graphene oxide for food packaging.