Composition and blowing agent for making foamed polyethylene material

摘要

Method and composition for making an expanded polyethylene material by forming a foamable melt of polyethylene, a nucleating agent, a material which retards migration of alkanes, and a blowing agent which comprises 10 to 100 mole percent ethane. In one disclosed embodiment, the melt is passed through an annular extrusion die to form an elongated tube of extruded material which is then expanded, slit lengthwise and laid flat to form a sheet of the expanded material.