The barrier to gases is also said to be substantial in the multi-layer film disclosed in U.S. Pat. No. 4,254,169, which discloses a multi-layer film comprising a core layer of vinyl alcohol polymers or copolymers, such as polyvinyl alcohol or ethylene vinyl alcohol adhered to one or more layers of a polyolefin blended with a chemically modified polyolefin having functional groups added to the basi