Patent ID: 6884377
Filing Date: 2005-04-26
Classification: B29C,B29K

Abstract:
1. A method comprising: establishing a stream of polymeric material flowing at a rate of at least about 5 lbs per hour within a polymer processing space between a rotating screw and an extruder barrel; introducing, into the stream of polymeric material, a blowing agent through a plurality of orifices of the extruder barrel while passing the orifices with a flight of the rotating screw; and admixing the polymeric material and the blowing agent to form a single-phase solution of polymeric material and blowing agent, wherein the blowing agent is present in the single-phase solution in an amount less than about 80 percent saturation concentration as determined at the lowest pressure in the extruder barrel after the point of blowing agent injection and prior to nucleating the single-phase solution.