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A delamination resistant multi-layer film comprises a core layer of vinyl alcohol polymers or copolymers such as polyvinyl alcohol or ethylene vinyl alcohol. Adhered to the core layer are one or more layers of a partially hydrolyzed vinyl acetate polymer or copolymer having functional groups in the

A delamination resistant multi-layer film comprises a core layer of vinyl alcohol polymers or copolymers such as polyvinyl alcohol or ethylene vinyl alcohol. Adhered to the core layer are one or more layers of a partially hydrolyzed vinyl acetate polymer or copolymer having functional groups in the polymer such that strong adhesion to the core layer is obtained. The core layer provides an excellent oxygen barrier, while the adjacent layers protect the core layer from degradation by exposure to water vapor. Additional layers of various polymer materials may be provided over the layers of partially hydrolyzed vinyl acetate. The film can be prepared by coextrusion techniques.

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A delamination resistant multi-layer structure comprising a barrier layer of a substantially pure polymer or copolymer of vinyl alcohol having less than about 1.5 mole percent remaining vinyl acetate groups and an adjacent adherent layer consisting essentially of a partially hydrolyzed vinyl acetate

A delamination resistant multi-layer structure comprising a barrier layer of a substantially pure polymer or copolymer of vinyl alcohol having less than about 1.5 mole percent remaining vinyl acetate groups and an adjacent adherent layer consisting essentially of a partially hydrolyzed vinyl acetate polymer or copolymer which has at least about 5 mole percent remaining vinyl acetate groups. A delamination resistant coextruded multi-layer structure comprising (a) a core layer of a substantially pure ethylene vinyl alcohol copolymer having less than about 1.5 mole percent remaining vinyl acetate groups; (b) an adherent layer adhered on each side of the core layer, the adherent layer consisting essentially of partially hydrolyzed polyvinyl acetate or partially hydrolyzed ethylene-vinyl acetate copolymer, to result in a polymer having at least about 5 mole percent remaining vinyl acetate groups; (c) an outer polymer layer over at least one of the adherent layers, the outer layers being independently selected from the group which consists of polyethylene, polypropylene, ethylene vinyl acetate copolymer, ethylene acrylic acid copolymer, blends of two or more of the foregoing polymers, nylon, and ionomers.