An extruder screw includes an extruder shaft and at least one extruder segment. The extruder shaft has a prismatic mandrel having external teeth and a longitudinal mandrel axis. The extruder segment has internal teeth and a longitudinal internal-teeth axis and can be slid onto the mandrel, such that the extruder segment can be connected to the mandrel for rotation therewith. The internal teeth have a profile having a meshing profile and, in an inner area between the first and second end faces of the extruder segment, include a prismatic main profile that has a main cross-section. Furthermore, the internal teeth of the extruder segment have an edge profile adjacent to at least one end face of the extruder segment, which edge profile has a smaller edge cross-section than the main profile at least in the area of the meshing profile.

A film that comprises a thermoplastic composition that contains a continuous phase that includes a polyolefin matrix polymer and a nanoinclusion additive dispersed within the continuous phase in the form of discrete domains is provided. The film is biaxially stretched in a machine direction and cross-machine direction to form a porous network in the composition. The porous network contains nanopores having a maximum cross-sectional dimension of about 800 nanometers or less. At least a portion of the nanopores are oriented in the cross-machine direction so that the axial dimension generally extends in the cross-machine direction and the cross-sectional dimension generally extends in the machine direction.

The present invention relates to a continuous process for preparing a comb polymer, without organic solvent, by esterification and/or amidification of an acidic homopolymer or copolymer, which consists in performing the esterification and/or amidification of said homopolymer/copolymer by reaction at elevated temperature in the mixing and transportation zone of a tubular reactor, optionally equipped with a water removal system, in the presence of at least one poly(alkylene glycol) in solid or molten form and of an antioxidant, said esterification and/or amidification taking place at a temperature greater than or equal to 170° C.

A self-cleaning extruding apparatus with two co-rotating screws and the method thereof are provided here. Said apparatus is comprised of a screw mechanism, a barrel (1), a feeding port (10), a venting port (11), and a discharge port (12). Said screw mechanism is comprised of the first screw with one tip (3) and the second screw with two tips (4). There is a baffle in the channel of the first screw and the baffle's height is lower than that of the screw flight. The baffle will cause hyperbolic perturbation in the shape of a ‘figure 8’ flow pattern above the top of the baffle. The first and second screws rotate at the same speed and touch each other at all times, thereby achieving a self-cleaning function.

The baffle will generate chaotic mixing in the screw channel caused by the hyperbolic perturbation. Topological chaos is also introduced into the screw channel by the mechanism ‘one part divided into two parts, then two parts converging into one part, and then one part divided into two parts once more’. Each of the screws in the present invention uses an asymmetrical flow channel geometrical shape, such that a periodic action like ‘compression—expansion—further compression—expansion further’ works. The above three enhancement mechanisms work together to efficiently accelerate melting and mixing.

Apparatus and methods for food production including a food preconditioner (228) operable to heat and partially pre-cook food ingredients, and a twin screw extruder (20) operable to further cook the preconditioned ingredients to create final food products. The extruder (20) includes a pair of hollow core extrusion screws (50, 52, 124, 126, 190) having elongated hollow core shafts (54, 128, 130, 192) equipped with helical fighting (56, 132, 134, 194) along the lengths thereof. The fighting (132, 134, 194) is also of hollow construction which communicates with the hollow core shafts (54, 128, 130, 192). The flighting (56, 132, 134, 194) also includes forward, reverse pitch sections (64, 162, 216). The extrusion screws (50, 52, 124, 126, 190) are designed to impart high levels of thermal energy into materials being processed in the extruders (20), without adding additional moisture.

The invention relates to a process for extruding plastic compositions. The process in particular relates to the conveying, kneading and/or mixing of plastic compositions, in particular of polymer melts and mixtures of polymer melts, above all thermoplastics and elastomers, particularly preferably polycarbonate and polycarbonate blends, also with the incorporation of other substances such as for example solids, liquids, gases or other polymers or other polymer blends.

The invention relates to a mixing device for a twin-screw extruder, in particular a twin-screw extruder rotating in the opposite direction, comprising a first screw and a second screw, for mixing a melt flow in a screw antechamber, wherein the first screw has an extension in the form of a mixing screw tip connected to the first screw in a fixed manner, and a first melt channel, into which the first screw feeds, is arranged in a flow-connected manner via an elongated slot with a second melt channel, into which the second screw feeds.

A vent assembly device for a twin-screw extruder includes a vent assembly (7) that has a vent opening (6) and that is provided in a cylinder (1) of a twin-screw extruder (11) having a left axis-side screw (2) and a right axis-side screw (3). The size of at least the vent opening (6) of the vent assembly (7) can be freely modified by forming the vent assembly (7) from a plurality of vent assembly units (7a) and by providing the plurality of vent assembly units (7a) for one vent opening (6).

A screw includes a screw main body, a conveyance portion conveying a raw material, and a passage provided in the screw main body. The passage includes a first passage element, a second passage element, and a third passage element. The screw main body has a plurality of cylindrical bodies arranged in an axial direction of the rotating shaft. At least a portion of the conveyance portion is formed on outer peripheral surfaces of the cylindrical bodies adjacent to each other, and the passage is formed in the cylindrical body so as to cross over between the adjacent cylindrical bodies.

An improved rotary head extruder incorporates an auger system comprising more than one auger to create asymmetrical, substantially cylindrical extruded products having a density within the range of about 3.0 to about 6.0 lbs./cu ft. A wide variety of fine particles such as flour and powder can be successfully introduced into and conveyed within a rotary head extruder to the die assembly, where the materials are cooked to form hard, dense extruded collets with randomly asymmetrical shapes. A transition piece at the downstream end of the augers allows for continuous, uniform flow to the die assembly, where cooking takes place. Using the equipment described, raw materials other than the typically used corn meal are produced, while maintaining the desired bulk density, texture, and crunch of random extruded products.