Abstract: The present technology relates to a process for polymerizing or copolymerizing ethylenically unsaturated monomers in the presence of free-radical polymerization initiators, wherein the polymerization is carried out in a continuously operated tubular reactor at temperatures from 100° C. to 350° C. and pressures from 180 MPa to 340 MPa, with a specific reactor surface area Asp of 2 m2/(t/h) to 5.5 m2/(t/h), and the tubular reactor has a specific ratio RDsp of 0.0050 MPa?1 to 0.0069 MPa?1 and an inner surface which has a surface roughness Ra of 2 ?m or less.

Abstract: A polymer filament or fiber comprising a polyethylene material (I) having the following features: a) a density of 0.900 g/cm3 or higher; b) a MI21 value of 25 g/10 min.; c) a MFR value from 25 to 60; the said fiber being stretched by drawing with a draw ratio from 1.5 to 10.

Abstract: A slurry polymerization process comprising polymerizing monomers in a reactor comprising baffles, a first slurry feed line for returning cooled slurry from a cooler and optionally a second slurry feed line for transferring reactor slurry from a previous reactor of a cascade of polymerization reactors, wherein the baffle top, the first slurry feed line discharge end and the second slurry feed line end are located below the reactor liquid level.

Abstract: The present disclosure relates to a polyethylene composition comprising copolymers of ethylene with 1-alkenes, or mixtures of ethylene homopolymers and said copolymers of ethylene with 1-alkenes, wherein the polyethylene composition has a molar mass distribution width (MWD) Mw/Mn of from 7 to 15, a density of from 0.942 to 0.954 g/cm3, a weight average molar mass Mw of from 20,000 g/mol to 500,000 g/mol, a MIE of from 1.0 to 3.0 g/10 min, a MIF of from 100 to 200 g/10 min, and a ratio MIF/MIE of from 40 to 50.

Abstract: The present disclosure relates to a polyethylene composition with improved swell ratio and mechanical properties for use in preparing blow-moulded articles and having the following features: 1) a density from 0.945 to less than 0.952 g/cm3; 2) an MIF/MIP ratio from 15 to 30; 3) a Shear-Induced Crystallization Index (SIC) from 2.5 to 5.5.

Abstract: The present technology relates to a process for polymerizing or copolymerizing ethylenically unsaturated monomers in the presence of free-radical polymerization initiators, wherein the polymerization is carried out in a continuously operated tubular reactor at temperatures from 100° C. to 350° C. and pressures from 180 MPa to 340 MPa, with a specific reactor surface area Asp of 2 m2/(t/h) to 5.5 m2/(t/h), and the tubular reactor has a specific ratio RDsp of 0.0050 MPa?1 to 0.0069 MPa?1 and an inner surface which has a surface roughness Ra of 2 ?m or less.

Abstract: The present disclosure relates to a polyethylene composition with improved swell ratio and mechanical properties, particularly suited for preparing blow-moulded articles, said composition having the following features: 1) a density from 0.952 to 0.960 g/cm3; 2) an MIF/MIP ratio from 17 to 30; and 3) a Shear-Induced Crystallization Index SIC from 2.5 to 5.0.

Abstract: A novel polyethylene formed by Ziegler catalyst is devised, for use in blow moulding.

Abstract: The present disclosure relates to a polyethylene composition with improved swell ratio and mechanical properties for use in preparing blow-moulded articles and having the following features: 1) a density from 0.945 to less than 0.952 g/cm3; 2) an MIF/MIP ratio from 15 to 30; 3) a Shear-Induced Crystallization Index (SIC) from 2.5 to 5.5.

Abstract: The present disclosure relates to a vessel for separating, at a pressure of from 10 MPa to 50 MPa, a composition comprising liquid components and gaseous components into a liquid fraction and a gaseous fraction, wherein the separation vessel has a vertically arranged cylindrical shape, has at its top a manhole, which is surrounded by a thickened part of the separation vessel wall; and bears at least one bursting disc which is held by a bursting disc holder which is installed pressure-tight within a boring in the thickened part of the separation vessel wall.

Abstract: The present disclosure relates to a process for separating polymeric and gaseous components of a reaction mixture obtained by high-pressure polymerization of ethylenically unsaturated monomers in the presence of free-radical polymerization initiators into in a gaseous fraction and a liquid fraction, wherein the separation is carried out at a pressure of from 15 MPa to 50 MPa and a temperature of from 120° C. to 300° C. in a separation vessel which has a vertically arranged cylindrical shape with a ratio of length to diameter L/D of from 4 to 10 and which is equipped with an inlet pipe which extends vertically from the top into the separation vessel; and the ratio of the inner diameter of the inlet pipe at its lower end and the inner diameter of the separating vessel in its cylindrical part is in the range of from 0.2 to 0.4.

Abstract: The present disclosure generally relates to a process for separating polymeric and gaseous components of a reaction mixture obtained by high-pressure polymerization of ethylenically unsaturated monomers in the presence of free-radical polymerization initiators into a gaseous fraction and a liquid fraction in a separation vessel, wherein the filling level of the liquid fraction in the separation vessel is measured by a radiometric level measurement system comprising at least two radioactive sources and at least three radiation detectors, and the filling level is controlled by a product discharge valve which operates based on data coming from the level measurement system.

Abstract: The present disclosure relates to a polyethylene composition of Raised Temperature Resistance, having the following features: 1) a density from 0.935 to 0.945 g/cm3; 2) a melt flow index MIF from 10 to 18 g/10 min; 3) a melt flow index MIP from 1 to 2.5 g/10 min; and 4) a MIF/MIP ratio from 5 to 10.

Abstract: The instant invention pertains to a process for preparing an ethylene homo- or copolymer in the presence of a supported chromium catalyst by slurry loop polymerization or copolymerization, whereby the resulting polymer powder has an increased powder density, in which the supported chromium catalyst has a chromium content of from 0.01 to 5 wt.-%, based on the element in the finished catalyst, and shows a particle size distribution measured according to ISO 13320-2009 comprising two main fractions one of which having a d50 of from 15 to 40 ?m and the other having a d50 of from 45 to 80 ?m said catalyst being further characterized by the fact that less than 10% wt of its catalyst particles has diameter lower than 20 ?m.

Abstract: Polyethylene composition with improved balance of environmental stress cracking resistance (FNCT) and impact resistance (Charpy), particularly suited for preparing pipes, said composition having the following features: 1) density from 0.945 to 0.955 g/cm3; 2) ratio MIF/MIP from more than 30 to 45; 3) Shear-Induced Crystallization Index SIC from 1.0 to 2.5; 4) Long Chain Branching index equal to or greater than 0.85.

Abstract: Process for treating polyolefin particles obtained by gas-phase polymerization of one or more olefins in the presence of a polymerization catalyst system and a C3-C5 alkane as polymerization diluent in a gas-phase polymerization reactor, the process comprising the steps of a) discharging the polyolefin particles continuously or discontinuously from the gas-phase polymerization reactor and transferring the particles to a first degassing vessel; b) contacting therein the polyolefin particles with a gaseous stream comprising at least 85 mol-% of C3-C5 alkane while the polyolefin particles have an average residence time in the first degassing vessel of from 5 minutes to 5 hours; c) transferring the polyolefin particles to a second degassing vessel; d) contacting therein the polyolefin particles with a stream comprising nitrogen and steam while the polyolefin particles have an average residence time in the second degassing vessel of from 5 minutes to 2 hours, wherein the contacting is carried out at conditions un

Abstract: The present disclosure relates to a polyethylene composition comprising copolymers of ethylene with 1-alkenes, or mixtures of ethylene homopolymers and said copolymers of ethylene with 1-alkenes, wherein the polyethylene composition has a molar mass distribution width (MWD) Mw/Mn of from 7 to 15, a density of from 0.942 to 0.954 g/cm3, a weight average molar mass Mw of from 20,000 g/mol to 500,000 g/mol, a MIE of from 1.0 to 3.0 g/10 min, a MIF of from 100 to 200 g/10 min, and a ratio MIF/MIE of from 40 to 50.

Abstract: The present technology relates to a process for polymerizing or copolymerizing ethylenically unsaturated monomers in the presence of free-radical polymerization initiators, wherein the polymerization is carried out in a continuously operated tubular reactor at temperatures from 100° C. to 350° C. and pressures from 180 MPa to 340 MPa, with a specific reactor surface area Asp of 2 m2/(t/h) to 5.5 m2/(t/h), and the tubular reactor has a specific ratio RDsp of 0.0050 MPa?1 to 0.0069 MPa?1 and an inner surface which has a surface roughness Ra of 2 ?m or less.

Abstract: The invention relates to a polyethylene molding composition having a multimodal molar mass distribution particularly suitable for blow molding films having a thickness in the range from 8 to 200 ?m. The molding composition has a density at a temperature of 23° C. in the range from 0.953 to 0.960 g/cm3 and an MFR190/5 of the final product after extrusion in the range from 0.10 to 0.50 dg/min. The composition comprises from 30 to 60% by weight of a first ethylene polymer fraction made of a homopolymer A having a first molecular weight, from 22 to 40% by weight of a second ethylene polymer fraction made of a further homopolymer or first copolymer B of ethylene and at least one first comonomer from the group of olefins having from 4 to 8 carbon atoms, the first copolymer B having a second molecular weight higher than the first molecular weight, and from 10 to 30% by weight of a third ethylene polymer fraction made of a second copolymer C having a third molecular weight higher than the second molecular weight.

Abstract: Polyethylene composition with improved swell ratio and mechanical properties, particularly suited for preparing blow-molded articles, said composition having the following features: 1) density from 0.945 to less than 0.952 g/cm3; 2) ratio MIF/MIP from 15 to 30; 3) Shear-Induced Crystallization Index SIC from 2.5 to 5.5.