Disclosed is a device for processing plastic materials, having a shredding unit, a conveying unit having a screw (7), and an extruder, having at least one extruder screw (11), adjoining the screw, wherein the central longitudinal axis (3) of the screw (7) is oriented at an angle to the central longitudinal axis (10) of the extruder screw (11), in particular at an angle of 80° to 100°, preferably 90°, and the longitudinal axis (3) of the screw (7) is offset with respect to the longitudinal axis (10) of the extruder screw (11) by an offset (v) in the direction of the direction of rotation (12) of the extruder screw (11) at or in the region of the discharge opening (8) or the intake opening (16) of the conveying unit.

Disclosed is a process for preparation of a propylene-based polymer composition involving the steps of: (a) mixing a propylene-based polymer and a peroxydicarbonate in a mixing device, wherein the mixing takes place at a temperature of ≤30° C., wherein the peroxydicarbonate is introduced into the mixing process in a dry form; (b) keeping the mixed composition at a temperature of ≤30° C.; (c) feeding the mixed composition into a melt extruder; (d) homogenizing the mixed composition at a temperature where the propylene-based polymer is in solid state during an average residence time of ≥6.0 and ≤30.0 seconds; (e) further homogenizing the mixed composition at a temperature at which the propylene-based polymer is in the molten state; and (f) extruding the homogenized material from a die outlet of the melt extruder followed by cooling and solidification; wherein the steps (a) through (f) are conducted in that order.

An extruder configured to extrude a solid raw material containing moisture includes a barrel, a hopper coupled to one side of the barrel, a discharge port, a screw, vent disposed between the hopper and the discharge port to discharge vapor generated within the barrel; and a heater mounted on the barrel to heat the raw material. Raw material introduced into the barrel through the hopper is heated by the heater while being transferred within the barrel through the screw. A kneading zone, in which raw materials transferred by the screw threads are compressed, is formed on the screw. Since the raw material is melted within the barrel, a heating temperature of the heater and an axial rotation speed of the screw are controlled so that a sealing membrane that shields an inner transverse section of the barrel is formed from the liquid raw material in the kneading zone.

An assembly for performing an additive manufacturing process includes a first material feed for dispensing a first material, a second material feed for dispensing a second material, a material combiner chamber, a first entry channel fluidly connecting the first material feed and the material combiner chamber, and a second entry channel fluidly connecting the second material feed and the material combiner chamber. The assembly further includes a pen tip for dispensing a material in the additive manufacturing process, the material comprising the first material and the second material, a valve having a rod, a first seal between the material combiner and the pen tip, and a first actuator for moving the rod back and forth along a longitudinal axis to open and close the first seal.

An extruder-mixer has a stator and a rotor arranged coaxially to the stator. The rotor is mounted rotatably relative to the stator. The stator, at least in portions, is arranged inside a volume spanned by the rotor. Such an extruder-mixer may be with an extruder. An extruder screw may be mounted in a screw housing of the extruder and coupled to a screw drive of the extruder.

An Extruder for shaping a viscous material such as a blend of rubber is disclosed herein. The extruder includes a screw rotationally driven about an axis (XX) in a barrel and bearing one or more helical flights extending radially outwards from a central shaft of the screw, the extruder comprising a material homogenization zone (H) through which a screw portion comprising interrupted flight elements forming empty annular spaces extends axially, and a barrel portion delimiting the said homogenization zone bearing flight elements extending radially inwards into the said empty annular spaces. According to the disclosure, the barrel portion delimiting the homogenization zone is itself rotationally driven about the axis XX to form a rotary barrel.

Disclosed is a process for preparation of a propylene-based polymer composition involving the steps of: (a) mixing a propylene-based polymer and a peroxydicarbonate in a mixing device, wherein the mixing takes place at a temperature of 30 C., wherein the peroxydicarbonate is introduced into the mixing process in a dry form; (b) keeping the mixed composition at a temperature of 30 C.; (c) feeding the mixed composition into a melt extruder; (d) homogenizing the mixed composition at a temperature where the propylene-based polymer is in solid state during an average residence time of 6.0 and 30.0 seconds; (e) further homogenizing the mixed composition at a temperature at which the propylene-based polymer is in the molten state; and (f) extruding the homogenized material from a die outlet of the melt extruder followed by cooling and solidification; wherein the steps (a) through (f) are conducted in that order.

An extruder for use in an additive manufacturing process. The extruder includes an inner housing and an outer housing. A material feed channel extends through the extruder. The material feed channel is positioned between the inner housing and the outer housing. The inner housing is mounted to allow the inner housing to rotate relative to the outer housing, and the outer housing is mounted to allow the outer housing to rotate relative to the inner housing. The rotation of the inner housing and outer housing moves material through the material feed channel and introduces shear forces to the material to decrease the viscosity of the material. A heating element is provided proximate the housing and extends about the entire circumference of the housing. The heating element provides even and controlled heating across the entire extruder.

An extrusion system includes a container defining a channel extending along an axis for holding a feedstock. A ram is located on a first axial side of the channel and a die assembly is located on a second axial side of the channel opposite the first axial side. The ram is axially movable to push the feedstock into the die assembly. The die assembly defines at least one aperture extending through a part of the die assembly. A shearing surface is configured to shear and heat the material prior to entering the at least one aperture. At least part of the shearing surface or the container are configured to rotate about the axis while the at least one aperture remains rotationally stationary.

An extruder configured to extrude a solid raw material containing moisture includes a barrel, a hopper coupled to one side of the barrel, a discharge port, a screw, vent disposed between the hopper and the discharge port to discharge vapor generated within the barrel; and a heater mounted on the barrel to heat the raw material. Raw material introduced into the barrel through the hopper is heated by the heater while being transferred within the barrel through the screw. A kneading zone, in which raw materials transferred by the screw threads are compressed, is formed on the screw. Since the raw material is melted within the barrel, a heating temperature of the heater and an axial rotation speed of the screw are controlled so that a sealing membrane that shields an inner transverse section of the barrel is formed from the liquid raw material in the kneading zone.