Barrier film for food packaging

A method for improving the barrier properties of a polyethylene film, said method comprising the steps of converting into a film a mixture comprising;

• a) from about 5 to about 60 weight percent, based on the total weight of said mixture, of a component a) comprising at least one high density polyethylene having a density of from about 0.950 to about 0.975 g/cc and a high melt index I2;
• b) from about 95 to about 40 weight percent, based on the total weight of said mixture, of a component b) comprising at least one high density polyethylene having a density of from about 0.950 to about 0.970 g/cc and a low melt index I2′, and;
• c) from about 100 to about 3,000 ppm of a calcium salt of 1,2-cyclohexanedicarboxylic acid;
• wherein, a melt index ratio, defined by dividing said high melt index I2 of said component a) by said low melt index I2′ of said component b), is greater than 10/1;
• wherein the water vapor transmission rate of said polyethylene film is improved, by being from about 20% to about 53% lower, relative to a control polyethylene film of the same composition but not containing said calcium salt of 1,2-cyclohexanedicarboxylic acid;
• wherein density is measured according to ASTM D 1505, and;
• wherein melt index is measured according to ASTM D 1238 when conducted at 190° C. using a 2.16 kg weight.