▎ 摘　　要

NOVELTY - A graphene/polyethylene naphthalate (PEN)/polyethylene terephthalate (PET) composite barrier film has an ABA three-layer structure comprising layer (A) made of PET, and a layer (B) made of graphene/PEN/PET composite material obtained by polymerization of terephthalic acid, 2,6-naphthalene dicarboxylic acid, polyethylene glycol and oxygen-absorbing graphene. The oxygen-absorbing graphene is prepared by azide reaction in the ball milling process of p-aminophenol and crystalline flake graphite. USE - Graphene/polyethylene naphthalate/polyethylene terephthalate composite barrier film for food packaging, medicine packaging and beverage bottle. ADVANTAGE - The graphene/PEN/PET composite barrier film prevents agglomeration of graphene, increases the barrier property of polymer matrix, has improved PET substrate self-barrier property, and prolongs the diffusion path of the gas in the substrate. The graphene on the surface can effectively absorb the oxygen entering the PET substrate, thus improving the barrier properties of the material. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the composite barrier film, which involves (s1) mixing graphite and p-aminophenol under the protection of nitrogen, adding isoamyl nitrite and ethylene glycol for ball milling for 4-48 hours, washing and separating, and vacuum-drying at 60°C to obtain oxygen-absorbing graphene, (s2) adding ethylene glycol under the protection of nitrogen, adding oxygen-absorbing graphene, mixing uniformly, adding terephthalic acid, 2,6-naphthalene dicarboxylic acid and catalyst, raising the temperature to 200-260°C, reacting terephthalic acid and 2,6-naphthalene dicarboxylic acid for 2-4 hours under the protection of nitrogen, raising the temperature to 270-290°C, carrying out polycondensation under the vacuum condition, reacting for 2-4 hours, discharging under the protection of nitrogen, solidifying and granulating to obtain oxygen-absorbing graphene/PEN/PET composite material granules, and (s3) multilayer extrusion bidirectional stretch film forming by three-layer extrusion process, directly conveying melt to a die head by a pump to extrude into sheet molten flow, cooling the quenching roller into composite thick sheet, and forming the composite barrier film by longitudinal stretching and transverse stretching to form a bidirectional stretch. The mass ratio of graphite, p-aminophenol, isoamyl nitrite and ethylene glycol is 1:0.1-10:0.1-10:5-50.