The invention relates to formulated compositions which can be easily formed into bottle caps, without the need for a liner, while still maintaining pressure requirements, such as for carbonated beverages. The compositions may include an ethylene polymer having a density in the range of from about 0.947 to 0.962 g/cm3, a melt index of from about 1 to about 10 g/10 min., and another ethylene polymer having a density in the range of from about 0.912 to 0.932 g/cm3, a melt index of from about 0.25 to about 6 g/10 min., wherein the two ethylene polymers have a density difference of equal to or greater than 0.03 g/cm3. In other cases, the composition may include a single component resin with a density in the 0.935-0.955 g/cm3 range with a melt index in the range of 0.3-1.2 g/10 minutes, and wherein the resin comprises a polyethylene polymer.