Abstract: A plastication unit for an injection molding machine, combining a heated plastication barrel with an entrance port and an exit port on opposing ends of the barrel; a hopper positioned to deliver ingredients to be compounded for injection molding to the entrance port of the barrel; and a helical plastication screw rotatably carried within the barrel and running the length of the barrel between the entrance and exit ports, which is operable to rotate and transmit the ingredients along the length of the barrel; wherein the plastication screw has at least one axial fluted extensional mixing element segment and the ingredients include at least one polymer for injection molding. Methods for injection molding with the plastication unit of the present invention and articles formed by the inventive methods are also disclosed.

Abstract: A plastication unit for an injection molding machine, combining a heated plastication barrel with an entrance port and an exit port on opposing ends of the barrel; a hopper positioned to deliver ingredients to be compounded for injection molding to the entrance port of the barrel; and a helical plastication screw rotatably carried within the barrel and running the length of the barrel between the entrance and exit ports, which is operable to rotate and transmit the ingredients along the length of the barrel; wherein the plastication screw has at least one axial fluted extensional mixing element segment and the ingredients include at least one polymer for injection molding. Methods for injection molding with the plastication unit of the present invention and articles formed by the inventive methods are also disclosed.

Abstract: A plastication unit for an injection molding machine, combining a heated plastication barrel with an entrance port and an exit port on opposing ends of the barrel; a hopper positioned to deliver ingredients to be compounded for injection molding to the entrance port of the barrel; and a helical plastication screw rotatably carried within the barrel and running the length of the barrel between the entrance and exit ports, which is operable to rotate and transmit the ingredients along the length of the barrel; wherein the plastication screw has at least one axial fluted extensional mixing element segment and the ingredients include at least one polymer for injection molding. Methods for injection molding with the plastication unit of the present invention and articles formed by the inventive methods are also disclosed.

Abstract: An extruder mixer and method for mixing plastic materials utilizes an elongated screw having an inlet channel connected to a first cross-axial pump that feeds, at an angle to the screw axis, a subsequent channel, wherein the subsequent channel becomes a further inlet channel connected to at least one subsequent cross-axial pump, and wherein the cross-axial pump is bounded by a flight on at least one side.

Abstract: An apparatus provided for extruding a polymer in an extruder barrel having an upstream portion and a downstream portion with a discharge port. A hopper is positioned for delivering polymer to the upstream portion of the extruder barrel and a screw shaft is mounted for rotational movement in the extruder barrel. A drive means is connected for rotating the screw shaft. The screw shaft has a conveying screw flight and a metering screw flight arranged for conveying and metering the polymer through the barrel. A seal is provided for sealing against polymer flow and includes at least two different passageways positioned between a seal barrel and at least one seal shaft mounted for rotational movement within the seal barrel. The passageways are oriented to urge the polymer toward the screw shaft.

Abstract: An apparatus is provided for extruding a polymer which is subject to periodic surges. The apparatus includes a barrel with an upstream portion for receiving polymer, a downstream portion and a discharge port near the downstream portion. The apparatus also includes a shaft mounted for rotational movement about a longitudinal axis within the barrel as well as drive means connected to rotate the shaft. The apparatus has a surge suppressor for urging polymer upstream toward the discharge port while permitting a portion of polymer to flow downstream into the surge suppressor. A sensor is positioned within the apparatus to detect surges in the polymer and a controller is connected to the sensor and to the drive means for adjusting shaft rotation in response to polymer surges.

Abstract: An apparatus and method for extruding an elastomeric polymer which is subject to periodic pressure surges. The apparatus includes a barrel having an upstream portion and a downstream portion, a hopper positioned for delivering polymer to the upstream portion of the barrel, a shaft rotationally mounted within the barrel and a drive means for rotating the shaft. The shaft has a conveying screw flight for conveying polymer downstream from the hopper through the barrel. The barrel has a discharge port located downstream of the hopper. A surge suppressor is provided on the shaft for reducing the pressure and flow rate surges in the polymer. The surge suppressor includes a screw flight downstream of the discharge port for urging the polymer upstream toward the discharge while permitting a portion of the polymer to flow downstream into the surge suppressor. A polymer seal is provided downstream of the surge suppressor.