US Patent 8076421 Film layers made from polymer formulations

Film layers made from formulated polymer compositions are disclosed. Film layers made from such formulated compositions have surprisingly good (for example, low) water vapor transmission rates and are particularly useful for packaging dry goods such as cereal. The polymer compositions preferably have at least one homogeneous ethylene homopolymer and at least one heterogeneously branched ethylene polymer. The homogeneous ethylene homopolymer has a molecular weight much higher than that of the heterogeneously branched ethylene polymer, although the density of each is preferably higher than about 0.95 g/cm3.