A process for recovery and devulcanization of vulcanized rubber is provided. The process takes place in a plant including a mill for grinding vulcanized rubber into particles, a twin-screw extruder provided with a device for forced feeding of vulcanized rubber particles and a thermostatting device, a single-screw extruder arranged downstream of the twin-screw extruder and equipped with a thermostatting device, a filter for devulcanized rubber and an extrusion die shaped like a slot, from the which devulcanized rubber comes out in the form of a strip or sheet, and a cooling device for the devulcanized rubber strip or sheet. The twin-screw extruder operates at a temperature between 35 and 450° C., with a rotation speed of the screws between 15 and 600 rpm, and a torque density between 11 and 18 Nm/cm.sup.3, so that the shear rate remains constant for the entire longitudinal extension of the twin-screw extruder.

A system for continuously treating recycled polymeric material includes a hopper configured to feed the recycled polymeric material into the system. An extruder can turn the recycled polymeric material in a molten material. In some embodiments, the extruder uses thermal fluids, electric heaters, and/or a separate heater. The molten material is depolymerized in a reactor. In some embodiments, a catalyst is used to aid in depolymerizing the material. In certain embodiments, the catalyst is contained in a permeable container. The depolymerized molten material can then be cooled via a heat exchanger. In some embodiments, multiple reactors are used. In certain embodiments, these reactors are connected in series. In some embodiments, the reactor(s) contain removable static mixer(s) and/or removable annular inserts.

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.

In the field of mixing rubber mixtures, o a rotor (100), for use in an internal mixer having a mixing vessel in which the rotor rotates includes one or more blades (104), each blade having a tip (104a) with a profile having a predefined curvature and an anti-wear device detachably fixed to the tip (104a) of at least one blade. The anti-wear device includes a plate (110) with a profile defined by a lower surface (112) with a curvature complementary to that of the tip (104a) and an upper surface (114) with a curvature complementary to that of a wall of the vessel to define, between them, a zone of minimum distance that allows a passage of the mixture between the plate (110) and the wall of the vessel. One or more fastening systems (135) are fitted and tightened with respect to the plate (110) so as to engage the rotor (100).

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.

An acrylic rubber bale excellent in storage stability and processability, a method for producing the same, a rubber mixture obtained by mixing the acrylic rubber bale, and a rubber cross-linked product of the rubber mixture are provided. The acrylic rubber bale according to the present invention includes an acrylic rubber having a reactive group and a weight average molecular weight (Mw) of 100,000 to 5,000,000, wherein an amount of gel insoluble in methyl ethyl ketone is 50% by weight or less, and pH is 6 or less.

This application is directed to polymer blends of polyethylene naphthalate, polytrimethylene terephthalate, and polyethylene naphthalate, for use in fibers, such as carpet fibers, and other applications. This application is also directed to methods of producing such polymer blends and fibers.

A sealing film suitable for food packaging is disclosed, which adopts the following solution. The sealing film comprises, in sequence, a PET layer, a VMPET layer and a PE layer from outside to inside, wherein the PE layer comprises 100-110 parts of PE, 15-20 parts of EVA, 15-20 parts of EAA, 55-60 parts of HDPE and 10-15 parts of LLDPE in parts by mass. In this manner, the addition of HDPE and LLDPE into the PE layer is intended to enhance the tensile strength of the sealing film.

An acrylic rubber sheet excellent in storage stability and processability, a method for producing the same, an acrylic rubber bale obtained by laminating the sheets, a mixture obtained by mixing the acrylic rubber sheet and the acrylic rubber bale, a method for producing the mixture and a rubber cross-linking product obtained by cross-linking the mixture. The acrylic rubber sheet comprises, an acrylic rubber mainly composed of a (meth) acrylic acid ester and having a weight average molecular weight (Mw) of 100,000 to 5,000,000 and a ratio (Mz/Mw) of a Z-average molecular weight (Mz) and a weight average molecular weight (Mw) is 1.3 or more, and the acrylic rubber sheet contains a phenolic anti-aging agent, and a gel amount is 50 wt % or less. The acrylic rubber sheet is extremely excellent in storage stability and processability and the sheet can be easily produced by the claimed method.

Installation for manufacturing cross-linkable polyethylene compounds which comprises a melting machine (101), a melt pump (102) and a filtration unit (103). The installation allows to produce cross-linkable polyethylene compounds that may be further used for manufacturing insulating parts of medium, high and extra-high voltage power cables. A method for manufacturing cross-linkable polyethylene compounds is further provided.