A method for forming a graphene-reinforced polymer matrix composite is disclosed. The method includes distributing graphite microparticles into a molten thermoplastic polymer phase; and applying a succession of shear strain events to the molten polymer phase so that the molten polymer phase exfoliates the graphite successively with each event until at least 50% of the graphite is exfoliated to form a distribution in the molten polymer phase of single- and multi-layer graphene nanoparticles less than 50 nanometers thick along the c-axis direction.

A screw for a plasticating apparatus has one or more helical flights. A portion of the screw has a plurality of advancing grooves arranged in a noncontinuous helix cut in the screw. The advancing grooves are dimensioned to receive material therein as the material is conveyed through the barrel. The screw has a plurality of noncontinuous cross-cut grooves traversing one or more of the advancing grooves. The cross-cut grooves have a second helix angle greater than the first helix angle and less than ninety degrees; and/or one or more of the cross-cut grooves have a third helix angle of about ninety degrees.

Methods, apparatuses, systems, and techniques relate to an extruder unit for producing preforms with a tube-like wall from a polymer melt and an associated extrusion process. The extruder unit has a receptacle for an exchangeable dispensing tool, it furthermore comprises at least two different and alternately usable profiling devices. These profiling devices have outlet-side fastening structures, which correspond in the various profiling devices and form the receptacle for the exchangeable dispensing tool, so that the profiling devices can be connected alternately to the same dispensing tool. In this way, any dispensing tool, depending on the wish of the customer, can be operated with different profiling devices, in particular, on the one hand, to carry out profiling by mandrel body movement or profiling by nozzle body movement.

Methods, apparatuses, systems, and techniques relate to a tube-forming device for an extruder unit or an extrusion device and a tube-forming process. The tube-forming device comprises at least one shaping sleeve, which is designed to shape a supplied stream of polymer melt from a substantially strand-like cross section into a tubular cross section. The shaping sleeve has a guiding passage embedded in the sleeve wall, such that the guiding passage is a cavity which lies within the sleeve wall and, in the radial direction of the shaping sleeve, is enclosed in a sealed manner with respect to the outer surfaces.

An improved screw has a shaft having a surface and a central axis and at least one flight extending helically along the surface of the shaft in successive turns. A continuous groove is formed in the surface of the shaft and extends between successive, pushing and trailing, turns of the flight at a selected angle greater than zero. The groove defines at least one generally triangular land having a base aligned with a pushing turn of the flight and an apex between successive turns of the flight. The groove also defines another generally triangular land having a base aligned with a trailing turn of the flight. Barriers or dams may be provided on the lands and in the grooves. A second continuous groove may also be formed in the surface of the shaft.

An improved screw has a shaft having a surface and a central axis and at least one flight extending helically along the surface of the shaft in successive turns. A continuous groove is formed in the surface of the shaft and extends between successive, pushing and trailing, turns of the flight at a selected angle greater than zero. The groove defines at least one generally triangular land having a base aligned with a pushing turn of the flight and an apex between successive turns of the flight. The groove also defines another generally triangular land having a base aligned with a trailing turn of the flight. Barriers or dams may be provided on the lands and in the grooves. A second continuous groove may also be formed in the surface of the shaft.

A single-screw extruder (100), and a method. The extruder (100) comprisesa cylindrical rotor member (1) having diameter (D) and length (L) and comprising a feeding zone (14), the rotor member (1) arranged in a barrel (2), the cylindrical surface of the rotor member (1) carrying cavity/cavities and/or projection(s) (5) arranged in helically extending rows, the helically extending row(s) of the rotor member (1) having a pitch (P) and depth (d) in the feeding zone (14) of the rotor member, and the extruder (100) further comprising a drive system (4) for the rotation of the rotor member (1) in the barrel (2). The relation of the depth (d) to the diameter (D) of the rotor member, i.e. d:D, is not more than 1:20, and the relation of the pitch (P) of the rotor member to the diameter (D) of the rotor member, i.e. P:D, is not more than 1:4.

A single-screw extruder (100), and a method. The extruder (100) comprisesa cylindrical rotor member (1) having diameter (D) and length (L) and comprising a feeding zone (14), the rotor member (1) arranged in a barrel (2), the cylindrical surface of the rotor member (1) carrying cavity/cavities and/or projection(s) (5) arranged in helically extending rows, the helically extending row(s) of the rotor member (1) having a pitch (P) and depth (d) in the feeding zone (14) of the rotor member, and the extruder (100) further comprising a drive system (4) for the rotation of the rotor member (1) in the barrel (2). The relation of the depth (d) to the diameter (D) of the rotor member, i.e. d:D, is not more than 1:20, and the relation of the pitch (P) of the rotor member to the diameter (D) of the rotor member, i.e. P:D, is not more than 1:4.

A method for forming a graphene-reinforced polymer matrix composite is disclosed. The method includes distributing graphite microparticles into a molten thermoplastic polymer phase; and applying a succession of shear strain events to the molten polymer phase so that the molten polymer phase exfoliates the graphite successively with each event until at least 50% of the graphite is exfoliated to form a distribution in the molten polymer phase of single- and multi-layer graphene nanoparticles less than 50 nanometers thick along the c-axis direction.

The invention relates to mixing elements that have a larger number of basic geometric periods per section and an improved dispersing effect for multi-shaft screw extruders comprising screw shafts that co-rotate in pairs. The invention further relates to the use of the mixing elements in multi-shaft screw extruders, a corresponding screw extruder comprising the mixing elements, and a method for extruding kneadable materials.