A method for producing a resin composition is provided. The method includes melting and kneading a thermoplastic resin having a transition temperature of less than 200 C. and a powder with a twin-screw kneading extruder. The powder is an inorganic filler having an apparent density of 0.1 to 1.5 g/ml. The resin is supplied from a supply port to the extruder, and the powder is supplied from a gravimetric feeder to the extruder through a screw type side feeder. A transport capacity of the side feeder is 2 times or more an effective volume of the powder per unit time. In the extruder, melting and kneading are performed under conditions in which resin pressure in a first kneading zone is 1 MPa or more, and resin pressure in a second kneading zone is less than 3 MPa, and gas is removed from a vent port.

A device for producing a dyed plastic melt and an undyed plastic melt includes a multi-shaft screw extruder, a first metering installation, a second metering installation, and a control installation for selecting between a first operating mode for producing the dyed plastic melt and a second operating mode for producing the undyed plastic melt. The first metering installation serves for feeding an undyed plastic material through a first infeed opening into a housing of the multi-shaft screw extruder, and the second metering installation serves for feeding at least one dyeing agent through a second infeed opening into the housing. In order for the undyed plastic melt to be produced, the plastic material is fed exclusively via the first infeed opening such that residual dyeing agent which is still located in the second metering installation or in the region of the second infeed opening does not contaminate the undyed plastic melt.

A method for producing a stabilizer composition for a polymer and a stabilizer composition produced by the method. At least one carboxylic acid is reacted with at least one metal compound, such as at least one metal hydroxide and/or at least one metal oxide and/or at least one metal carbonate, thereby forming a metal carboxylate of the carboxylic acid. The reaction of the carboxylic acid with the metal compound is carried out in a continuous manner in an extruder while reaction water being formed is discharged out of the extruder.

The present invention relates to a method for the production of polyamide 6 with low extract content and a device for it. Here, a melt of non-extracted polyamide 6 is cleaned from monomer and oligomers in a degasification device in vacuum, wherein the vapor being withdrawn from the degasification device by the vacuum generation device is cleaned from monomer, oligomers and optionally water at first in a direct condenser which is operated with liquid -caprolactam and subsequently in a pre-separator which is cooled with a coolant, before it reaches the vacuum generation device. A particularly preferable variant of the method envisages the usage of the melt of polyamide 6 with low extract content so prepared in a direct process of spinning into textile fibers and/or filaments.

A screw extruder for extruding a kneaded material includes a screw and a casing housing the screw and having a material supply port on an upstream side in an extrusion direction of the kneaded material and a tip-side opening on a downstream side in the extrusion direction. A pressure sensor for measuring a pressure inside the casing is provided between a downstream end of the supply port and the tip-side opening of the casing. A rotational speed of the screw is controlled depending on the pressure measured by the pressure sensor.

A screw extruder for extruding a kneaded material, includes: a screw; and a casing housing the screw and having a material supply port on an upstream side. The screw has a shaft portion and a helical flight portion provided on an outer peripheral surface of the shaft portion. Regarding a clearance between a top portion of the flight portion and an inner wall surface of the casing, the clearance at a downstream side end of the flight portion is larger than the clearance at a downstream side end of the supply port. No area where the clearance decreases from the upstream side toward the downstream side is present between the downstream side end of the supply port and the downstream side end of the flight portion.

The invention relates to a method of preparing reclaimed rubber, especially using multi-stage screw extruders, which belongs to the field of recycling and reusing of waste rubber. The rubber powder and softener which were preliminarily mixed are compacted and added into first counter rotating twin screw extruder through thermal insulation and metering apparatus, the softener permeates the waste rubber powder uniformly under the action of temperature in the extruder to finish primary desulfurization of rubber waste powder; add preliminary devulcanized material continuously into second multi screw extruder after cooling by transformation device, rapid desulfurization and regeneration can be achieved by means of activator and shear action; The desulfurized rubber powder is cooled and transported into the third multi-screw extruder in series, the performance of deprocessing can be improved by shear action under low temperature; After extrusion, the recycled rubber is obtained by molding device and cooling device. The whole process is completed under closed oxygen isolation condition, realizing safe, simple and continuous desulfurization regeneration. It is energy saving and environmental protection with excellent properties.

It is described an apparatus for the extrusion and mixing of plastic materials, for example rubber-based and silicone-based materials, comprising a dump extruder body whereon two conical screws (2) converging towards an extrusion die (3) suitable for being occluded by closing means (4) are mounted, the conical screws (2) being accommodated within a low-pressure compounding chamber (1) and within a pair of converging conical channels also defining a high-pressure chamber (2), said low-pressure chamber (1) corresponding to an upstream area with respect to an extrusion direction, wherein said high-pressure chamber (2) and/or said low-pressure chamber (1) accommodate a presser body (5, 5, 6), defining a movable wall suitable for causing a controlled change in the volume of the respective chamber (1, 2).

A feeding screw machine for feeding a processing screw machine comprises a housing with at least two housing bores formed therein and screw shafts rotatably arranged in the at least two housing bores. The at least two housing bores and the at least two screw shafts define a free volume in a respective cross-sectional plane, which decreases monotonically at least in some regions for continuous compression of a material in a conveying direction. This enables an improved supply of material with a low bulk density.

A process for producing moldings from a powder based on thermoplastic elastomers, wherein the powder is placed on a mold or in a mold and by means of electromagnetic radiation is heated to an extent such that the powder undergoes at least partial melting and thus fuses to afford the molding and the frequency of the electromagnetic radiation is between 0.01 GHz and 300 GHz.