Abstract: Methods and systems that include introducing blowing agent into a hopper of a polymeric foam system.

Abstract: Methods and systems that include introducing blowing agent into a hopper of a polymeric foam system.

Abstract: Blowing agent introduction polymeric foam processing methods and systems are described herein.

Abstract: Methods and systems that include introducing blowing agent into a hopper of a polymeric foam system.

Abstract: Methods and systems of introducing blowing agent in a polymeric foam process are described. The methods and systems may be used to discontinuously introduce blowing agent in polymeric foam processes (e.g., injection molding processes) that discontinuously plasticate polymeric material.

Abstract: Systems and methods of processing polymer foam materials are provided. The methods involve introducing blowing agent downstream of an extruder. For example, the blowing agent may be introduced into a static mixing device positioned between the extruder and a mold. The methods may be used in connection with injection molding systems to produce high quality injection molded polymer foam articles.

Abstract: Continuous polymeric extrusion nucleation systems and methods useful for making polymeric microcellular foamed materials, including crystalline and semi-crystalline polymeric microcellular materials, are provided. Pressure drop rate is an important feature in some embodiments, and the invention provides systems for controlling these and other parameters. One aspect involves a multiple-pathway nucleator that is separated from a shaping die by a residence chamber. Another aspect involves a die for making advantageously thick articles, including a multiple-pathway nucleation section. Microcellular material can be continuously extruded onto wire, resulting in a very thin, essentially closed-cell microcellular insulating coating secured to a wire. Other very thin microcellular products can be fabricated as well.

Abstract: The invention provides a blowing agent delivery system for introducing a blowing agent into a polymeric foam processing system. The delivery system is designed to discontinuously introduce blowing agent from a continuous source into polymeric material within an extruder. The system, thus, may improve control over blowing agent delivery in discontinuous polymer processing systems such as injection molding or blow molding. In some embodiments, the blowing agent delivery system selectively directs blowing agent flow from the source to the extruder barrel, or through a bypassing passageway. In this manner, blowing agent may be continuously supplied by the source but discontinuously injected into the extruder barrel. During use, the delivery system may cause blowing agent to flow through the bypassing passageway, for example, when the screw stops plasticating polymeric material.

Abstract: Continuous polymeric extrusion nucleation systems and methods useful for making polymeric microcellular foamed materials, including crystalline and semi-crystalline polymeric microcellular materials, are provided. Pressure drop rate is an important feature in some embodiments, and the invention provides systems for controlling these and other parameters. One aspect involves a multiple-pathway nucleator that is separated from a shaping die by a residence chamber. Another aspect involves a die for making advantageously thick articles, including a multiple-pathway nucleation section. Microcellular material can be continuously extruded onto wire, resulting in a very thin, essentially closed-cell microcellular insulating coating secured to a wire. Other very thin microcellular products can be fabricated as well.

Abstract: A valve for controlling the flow of a high pressure fluid is provided. The valve provides a reliable way of controlling the flow of high pressure fluids in applications requiring multiple cycles where equipment may be exposed to environmentally harsh conditions, such as high temperatures and pressures.

Abstract: The invention provides a blowing agent metering system and method for use in polymeric foam processing. The system may be used to control the rate of introduction of blowing agent into polymeric material in a processing apparatus to form a mixture having the desired blowing agent weight percentage. The metering system includes a restriction orifice which is positioned in a pathway between a blowing agent source and a blowing agent port within a foam processing apparatus. The metering system measures the pressure differential as blowing agent flows across the restriction orifice from the source to the port and may also measure the temperature of the blowing agent at one or more locations. Using a pre-determined relationship between the flow rate, the orifice dimensions (e.g., length, diameter) and the measured variables (e.g.

Abstract: A valve for controlling the flow of a high pressure fluid is provided. The valve provides a reliable way of controlling the flow of high pressure fluids in applications requiring multiple cycles where equipment may be exposed to environmentally harsh conditions, such as high temperatures and pressures.

Abstract: The invention provides a blowing agent delivery system for introducing a blowing agent into a polymeric foam processing system. The delivery system is designed to discontinuously introduce blowing agent from a continuous source into polymeric material within an extruder. The system, thus, may improve control over blowing agent delivery in discontinuous polymer processing systems such as injection molding or blow molding. In some embodiments, the blowing agent delivery system selectively directs blowing agent flow from the source to the extruder barrel, or through a bypassing passageway. In this manner, blowing agent may be continuously supplied by the source but discontinuously injected into the extruder barrel. During use, the delivery system may cause blowing agent to flow through the bypassing passageway, for example, when the screw stops plasticating polymeric material.

Abstract: Continuous polymeric extrusion nucleation systems and methods useful for making polymeric microcellular foamed materials, including crystalline and semi-crystalline polymeric microcellular materials, are provided. Pressure drop rate is an important feature in some embodiments, and the invention provides systems for controlling these and other parameters. One aspect involves a multiple-pathway nucleator that is separated from a shaping die by a residence chamber. Another aspect involves a die for making advantageously thick articles, including a multiple-pathway nucleation section. Microcellular material can be continuously extruded onto wire, resulting in a very thin, essentially closed-cell microcellular insulating coating secured to a wire. Other very thin microcellular products can be fabricated as well.

Abstract: The present invention provides microcellular articles, as well as methods and apparatuses for producing polymeric foams, and, in particular microcellular material. The methods involve forming a gas blanket within a polymer processing die that prevents contact between the polymer melt and surfaces of the die during extrusion. In one set of embodiments, the gas blanket is provided by gas diffusing out of surfaces of the nucleated polymer material. In other embodiments, the gas blanket is formed by introducing a gas from an external source into the polymer flow channel within the die. The dies, according to the invention, are specially configured to generate and to support the gas blanket. The extruded foams are free of surface defects that, typically, arise from contact between the polymer melt and the die surfaces.