▎ 摘　　要

NOVELTY - Polyvinyl alcohol barrier film comprises polyvinyl alcohol, polyatomic alcohol compound, mixed water dispersion of nano-particle as casting film liquid to prepare film, where the nano-particle is one of silicalite-1 molecular sieve, polyhedral oligomeric silsesquioxane, graphene oxide, nitrogen carbide material and graphene. The fil has high temperature resistance and high humidity resistance. USE - Polyvinyl alcohol barrier film. ADVANTAGE - The polyvinyl alcohol barrier film maintains excellent barrier properties in high temperature and high humidity environments. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing polyvinyl alcohol barrier film, which involves: (A) preparing the casting solution by using polyvinyl alcohol, polyatomic alcohol compound, mixed aqueous dispersion of nano-particle for further use; (B) preparing liquid film by making the casting solution into the liquid film with the thickness of 10-200 microns under the condition of 80-95 degrees C; (C) drying the liquid film for 2-15 minutes at 100-110 degrees C to obtain the polyvinyl alcohol mixed substrate film; and (D) accurately controlling low temperature heat cross-linking by heating the polyvinyl alcohol mixed matrix membrane under atmosphere of oxygen and nitrogen at 80-150 degrees C for 1-24 hours, then raising the temperature to 160-280 degrees C for 6-72 hours, cooling to obtain the polyvinyl alcohol barrier.