According to one embodiment, an extruder screw includes a screw body. The screw body is rotated about an axis parallel to a direction of conveyance of a raw material. A conveyance portion having a flight is provided on the outer peripheral surface of the screw body. The flight is configured to convey the raw material along the axis of the screw body when the screw body is rotated. A passage for permitting the raw material fed by the flight to pass therethrough to the outer peripheral surface of the screw body is provided in the screw body in a position deviated from the axis of the screw body.

A polyamide resin is produced by polycondensing a polyamide oligomer having a relative viscosity of from 1.1 to 1.3 and a water content of 3% by weight or less by melt-kneading using an intermeshed co-rotation twin screw extruder having at least one or more open vents OV1 and OV2 and at least one or more vacuum vents VV1 and VV2. A pressure-decreasing element Y for increasing the resin filling rate is provided at a position nearer to the supply section side than positions at which the vacuum vents VV1 and VV2 are provided, and an area of 30% or less of the total screw length is a vacuum area having a pressure of 300 Torr or less.

An extruder screw including an elongated cylindrical tension rod; screw segments including radially protruding functional elements configured to feed, mix, and/or knead an extrudate, and a respective pass through bore hole oriented in a longitudinal direction of the extruder screw, wherein the screw segments are slid onto the tension rod with the pass through bore hole and axially supported at a tip of the tension rod; a counter element that clamps the screw segments against the tip of the tension rod at an end of the tension rod wherein the end is arranged distal from the tip; and a locking element that is clamped between the screw segments and the counter element.

A kneading apparatus includes a processor and an extruder. The extruder includes a screw. The screw includes a screw main body. A conveyance portion, a barrier portion, and a path are provided at places of the screw main body. In at least one of the places, the path is provided inside the screw main body and includes an entrance and an exit. The raw materials, pressure on which is increased by the barrier portion, flow in from the entrance. The raw materials flowing in from the entrance flow through the path toward the exit. The exit is positioned to be remote from the entrance in an axial direction. A method of using the kneading apparatus includes continuously melting and mixing materials in the processor, using the melted materials as the raw materials, and continuously discharging kneaded materials produced by kneading the raw materials with the screw in the extruder.

A kneading apparatus includes a processor and an extruder. The extruder includes a screw. The screw includes a screw main body. A conveyance portion, a barrier portion, and a path are provided at places of the screw main body. In at least one of the places, the path is provided inside the screw main body and includes an entrance and an exit. The raw materials, pressure on which is increased by the barrier portion, flow in from the entrance. The raw materials flowing in from the entrance flow through the path toward the exit. The exit is positioned to be remote from the entrance in an axial direction. A method of using the kneading apparatus includes continuously melting and mixing materials in the processor, using the melted materials as the raw materials, and continuously discharging kneaded materials produced by kneading the raw materials with the screw in the extruder.

A method for producing a polycarbonate resin composition pellet with a twin screw extruder, the polycarbonate resin composition pellet has 30 to 95 mass % of a resin pellet (A) containing more than 40 mass % of a polycarbonate resin in the pellet; not less than 5 mass % and less than 40 mass % of a phosphate ester flame retardant (B) that is a liquid at room temperature; 0 to 50 mass % of polycarbonate resin flake (C); 0 to 30 mass % of an ABS resin (D); and 0 to 15 mass % of an additive (E) other than component (B). The method includes feeding components (A), (C), (D) and (E) in a twin screw extruder and kneading with a first kneading zone; feeding component (B) to a downstream part in the first kneading zone and kneading with a second kneading zone; and decompressing a vent in the downstream part in the second kneading zone.

A method for manufacturing a heat resistant resin composition having superior dispersibility of maleimide-based copolymer, the method including: a melt-kneading step to melt and knead a maleimide-based copolymer (A) and at least one resin (B) selected from the group consisting of ABS resin, ASA resin, AES resin, and SAN resin with an extruder; wherein: a ratio of a melt viscosity of the maleimide-based copolymer (A) with respect to a melt viscosity of the resin (B) obtained with a shear rate of 120/sec and a cylinder temperature of a kneading unit of the extruder is 1.0 or higher and lower than 3.4, is provided.

A method for manufacturing a heat resistant resin composition having superior dispersibility of maleimide-based copolymer, the method including: a melt-kneading step to melt and knead a maleimide-based copolymer (A) and at least one resin (B) selected from the group consisting of ABS resin, ASA resin, AES resin, and SAN resin with an extruder; wherein: a ratio of a melt viscosity of the maleimide-based copolymer (A) with respect to a melt viscosity of the resin (B) obtained with a shear rate of 120/sec and a cylinder temperature of a kneading unit of the extruder is 1.0 or higher and lower than 3.4, is provided.

Process for treatment of an initial polyethylene-containing material to produce a polyethylene composition comprising providing a twin-screw extruder with thermal regulation devices; providing an initial polyethylene-containing material comprising at least 50 wt. % of polyethylene based on the total weight of the initial polyethylene-containing material; extruding the initial polyethylene-containing material to obtain a polyethylene composition; wherein extrusion is performed with a residence time of less than 20 min; and recovering a polyethylene composition; wherein extruding comprises a thermal treatment of the initial polyethylene-containing material at a temperature of at least 300 C. in one or more hot zones of the extruder by self-heating to have a maximum barrel temperature ranging from 300 to 460 C. in at least one hot zone of the extruder.

A method for extruding a recycled polymer from an impure extrudable material comprises injecting a non-solvent in a liquid state into an apparatus and mixing substantially homogeneously the non-solvent with the impure extrudable material, thereby forming a dispersion of the non-solvent with the impure extrudable material. The impurities are output in a gaseous state from the apparatus.