A machine for mixing elastomeric materials with a drive and mixing unit where the mixing chamber is arranged downstream of the drive unit; and a discharge chamber is arranged downstream of the mixing chamber. They communicate towards upstream, and are provided with a discharge opening for discharging the mixture. They include a signal indicating the presence or absence of a mixture. The machine can cause during a mixing step, at least one reversal by the drive unit of a sense of rotation of the rotors and therefore of a sense of advancing movement in the axial direction of the mixture from/towards the mixing chamber and towards/from the discharge chamber, to keep mixing of the mixture active only inside the mixing chamber.

A Machine for mixing elastomeric materials with a mixing unit, and a drive unit; the mixing unit has a mixing chamber arranged downstream of the drive unit and closed by a rear wall, a discharge chamber arranged downstream of the mixing chamber, with which it communicates and provided with an opening for discharging the mixture; a pair of inter-penetrating and counter-rotating conical rotors connected with the drive unit and having their vertices situated at the mouth of the discharge chamber. The rotors are rotated by the drive unit in a first sense (RPM+) to cause the mixture to be pushed towards the rear wall of the mixing chamber so as to keep mixing active only inside the mixing chamber, and in second sense of rotation, opposite to the first sense, to cause the mixture to be pushed towards the chamber and the discharge opening for discharging thereof.

A method for producing a resin composition of the present invention is a method for producing a resin composition, the method including a step of obtaining a resin composition by heating and melt-kneading a mixture containing a particulate nucleating agent in which D.sub.50 is equal to or more than 0.1 μm and equal to or less than 300 μm and a thermoplastic resin using a twin screw extruder (100) including, inside a cylinder (10), a screw (50) having kneading discs (60), in which the step of obtaining a resin composition includes an extrusion step of extruding the mixture supplied into the twin screw extruder (100) in an ejection direction under kneading conditions in which X and Y satisfy 4.0≤X in a range of 6.0×10.sup.3≤Y≤7.0×10.sup.4 when a volume-based ejection amount is denoted by X (10.sup.−6.Math.kg.Math.h.sup.−1.Math.mm.sup.−3), and a strain rate is denoted by Y (min.sup.−1).

The present invention relates to a method for preparing thermoplastic polymer particles, the method comprising the steps of: (1) extruding a thermoplastic polymer resin by means of an extruder; (2) granulating the extruded polymer resin by using an inert gas; and (3) cooling the granulated thermoplastic polymer resin, and thermoplastic polymer particles prepared thereby.

Disclosed is a recycling apparatus for a cross-linked polyethylene resin using a twin screw extruder. The recycling apparatus for a cross-linked polyethylene resin using a twin screw extruder according to an embodiment of the present disclosure includes: a raw material supply unit configured to supply a raw material that is a cross-linked polyethylene resin; and a twin screw extruder configured to receive the raw material from the raw material supply unit, the twin screw extruder including a cylinder and a twin screw installed inside the cylinder to rotate in the same direction, the twin screw extruder being configured to de-crosslink and recycle the raw material under a de-crosslinking reaction temperature and reaction pressure atmosphere while continuously transporting the raw material along the twin screw by the rotation of the twin screw.

A process for the manufacture of a tread band for pneumatic tyres, wherein the blocks thereof comprise different rubber portions characterized by a different hysteresis loss. The process comprises a shredding step, wherein from a first and from a second rubber tread compound a plurality of fragments is manufactured with dimensions of between 6 and 30 mesh; a mixing step, wherein the fragments from the first and second compound are mixed together in order to obtain a mixture wherein said fragments are distributed in a random manner and retain their chemical/physical individuality; and an extrusion step, wherein the mixture from the preceding step is extruded for the manufacture of the tread band. The first and second compounds have different dynamic properties in terms of: dynamic modulus at 30° C., tand at 0° C., tand at 30° C. and tand at 60° C. The fragments retain a chemical/physical individuality both within the mixture formed during the mixing step and within the tread band formed during the extrusion step.

Polymer compositions comprising high structure filler materials and methods for preparing such compositions while retaining structure.

Crumb rubber obtained from recycled tires is subjected to a process involving photodissociation to break a sulfur bond, sulfur-sulfur and/or sulfur-carbon bonds. The process utilizes a component that generates photonic energy upon being subjected to a compressing force (e.g., pressure). The photonic energy is bandwidth resonant with the sulfur-sulfur and/or sulfur-carbon bond, causing the bond to break apart. The resulting rubber is suitable for use in applications typically utilizing virgin rubber, such as new tires, engineered rubber articles, and asphalt rubber for use in waterproofing and paving applications.

Systems for manufacturing bulked continuous filament having tonal coloring from PET comprise, in various embodiments: (1) an extruder; (2) a static mixing assembly coupled to the extruder comprising: (a) a housing, and (b) one or more individual static mixing elements disposed within the housing; (3) a plurality of colorant ports along a length of the static mixing assembly such that each of the plurality of colorant ports is configured to provide colorant to a polymer stream at a different location along the length of the static mixing assembly; and (4) one or more spinning machines positioned downstream of the static mixing assembly and coupled to the static mixing assembly to receive the colored polymer stream. The spinning machine(s) may be configured to form the colored polymer stream into bulked continuous carpet filament having a tonal color effect.

A method for producing a polycondensate melt from a primary material and a secondary material from materials of substantially the same type is provided. A first partial melt stream of the primary material and a second partial melt stream of the secondary material are provided, and a measured value of the intrinsic viscosity of both partial melt streams is determined, and a difference value is calculated from the measured values. Based on the difference value, the intrinsic viscosity of the second partial melt stream is increased, reduced or maintained unchangedly by using a first melt treatment device. Subsequently, the two partial melt streams are combined into a common melt stream.