▎ 摘　　要

NOVELTY - High-barrier breathable flexible packaging bag comprises 40-60 pts. wt. polylactic acid micro-porous film, 5-12 pts. wt. chitosan, 2-6 pts. wt. glutaraldehyde, 8-15 pts. wt. modified graphene oxide and 6-8 pts. wt. polyethyleneimine. USE - Used as high-barrier breathable flexible packaging bag. ADVANTAGE - The bag: has good barrier properties and air permeability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing high-barrier breathable flexible packaging bag comprising (1) dissolving polylactic acid in methylene chloride, pouring into a film under certain humidity conditions, and drying to obtain polylactic acid micro-porous film, (2) mixing polyethyleneimine with water, and adding obtained polylactic acid micro-porous membrane to amination, filtering, and drying to obtain a pretreated polylactic acid micro-porous membrane, (3) dissolving chitosan in an acetic acid solution, adding potassium tetrachloropalladate, stirring and mixing to obtain first treatment solution, mixing polyallylamine hydrochloride with water to obtain a second treatment liquid, (4) mixing pretreated polylactic acid microporous membrane with obtained first treatment liquid, allowing to stand, filtering, and drying to obtain filter cake, (5) mixing obtained filter cake with obtained second treatment liquid, allowing to stand, filtering, and drying to obtain a pre-modified polylactic acid micro-porous membrane, (6) mixing obtained pre-modified polylactic acid microporous film with water, adding glutaraldehyde and a reducing agent, stirring reaction, filtering, and drying to obtain a blank, mixing blank pre-modified graphene oxide suspension, allowing to stand, filtering and drying, (7) repeating processing steps of (5)-(6) for 2-3 times to obtain a high-barrier ventilated flexible packaging bag blank, and the high-barrier ventilated flexible packaging bag is made frequently in a bag making machine to obtain a high-barrier ventilated flexible packaging bag, and (8) performing index analysis on obtained high-barrier breathable flexible packaging bag.