Polyolefin foam/film composite and method for making the same

The present invention relates generally to polyolefin foam/film composite structures and, more particularly, to such composites that are used as flooring underlayments for laminate floors. A composite structure, which includes:a. a foam sheet comprising polyolefin; andb. a film sheet adhered to the foam sheet, wherein the film sheet(1) comprises polypropylene,(2) is stretch-oriented in at least one direction,(3) has a thickness of less than 0.9 mil, and(4) has a larger surface area than the foam sheet such that at least one edge of the film sheet extends beyond a corresponding edge of the foam sheet.