Abstract: A high-pressure polymerization system having a) a polymerization reactor and b) a reactor blow down system having b1) a reactor blow down vessel, having a circular design over a major portion P having a L/D-ratio in the range from 1.75 to 10.0 and containing an aqueous quenching medium, b2) a release line connecting the polymerization reactor with the reactor blow down vessel and having an outlet located above a maximum level for the aqueous quenching medium, b3) a first emergency valve in the release line to open and close fluid communication between the polymerization reactor and the reactor blow down system, and wherein the release line outlet has a joining piece having an angle (a) between the central axis and a tangent at the reactor blow down vessel in the range from 5° to 70° and the reactor blow down vessel has a vent stack containing a constricted section.

Abstract: A consumable filament and process for using the consumable filament in an extrusion-based additive manufacturing system made from or containing a heterophasic polypropylene composition having a xylene soluble content ranging from 15 wt % to 50 wt %, a melt flow rate MFR L ranging from 0.5 to 100 g/10 min, an intrinsic viscosity of the fraction soluble in xylene at 25° C. ranging from 1.5 to 6.0 dl/g, and an ethylene content ranging from 10 wt % to 50 wt %.

Abstract: A slurry polymerization process for the preparation of polyethylene in a reactor cascade of two or more polymerization reactors wherein monomers are polymerized in the polymerization reactors which include a reactor outlet arranged in each reactor bottom for feeding a reactor slurry to a subsequent polymerization reactor and for emptying the polymerization reactor.

Abstract: A nano platelet gibbsite treated with compound of formula (ORa)3Si—Rb or of formula Rc—COOH wherein Ra equal to or different from each other is a C1-C10 alkyl radical; Rb is a C5-C30 hydrocarbon radical and Rc is a C5-C30 hydrocarbon radical is used as a catalyst support.

Abstract: A process for preparing an olefin polymer, including the steps of forming a particulate olefin polymer in a gas-phase polymerization reactor in the presence of a C3-C5 alkane as polymerization diluent, separating discharged polyolefin particles from concomitantly discharged gas at a pressure from 1 to 2.2 MPa, degassing the polyolefin particles at a pressure from 0.1 to 0.4 MPa with a gas made from or containing a C3-C5 alkane; and transferring the separated gas and the gas from the degassing to a work-up unit operated at a pressure from 0.001 to 0.2 MPa below the pressure of the separation, wherein the gas for degassing is continuously received from the work-up unit.

Abstract: A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) density from 0.940 to 0.955 g/cm3, determined according to ISO 1183 at 23° C.; 2) ratio MIF/MIP from 12 to 40; 3) Mz from 500,000 to 3,500,000 g/mol; 4) ?0.02 from 80,000 to 300,000 Pa·s; 5) HMWcopo index from 1 to 15; and 6) Mz/Mw*LCBI lower than 6.4.

Abstract: A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) density from 0.940 to 0.955 g/cm3 determined according to ISO 1183 at 23° C.; 2) ratio MIF/MIP from 12 to 30; 3) Mz from 2,000,000 to 4,500,000 g/mol; 4) ?0.02 from 160,000 to 300,000 Pa·s; and 5) long-chain branching index, LCBI, equal to or greater than 0.75.

Abstract: Polyethylene composition with improved balance of mechanical and optical properties, comprising (all percentages being by weight): A) from 90 to 99.7% of a LLDPE having a density from 0.91 to 0.94 g/cm3 and a ratio MIF/MIE equal to or higher than 20, where MIF is the melt flow index at 190° C. with a load of 21.60 kg, and MIE is the melt flow index at 190° C. with a load of 2.16 kg, both determined according to ISO 1133; B) from 0.3 to 10% of a LDPE having MIE from 0.1 to 0.6 g/10 min.

Abstract: An extrusion additive manufacturing process including the step of extruding a polyethylene composition having a melt flow index MIE of at least 0.1 g/10 min., the composition made from or containing: A) from 1% to 40% by weight of a polyethylene component having a weight average molar mass Mw, as measured by GPC (Gel Permeation Chromatography), equal to or higher than 1,000,000 g/mol; B) from 1% to 95% by weight of a polyethylene component having a Mw value from 50,000 to 500,000 g/mol; and C) from 1% to 59% by weight of a polyethylene component having a Mw value equal to or lower than 5,000 g/mol.

Abstract: Fluidized-bed reactor for the gas-phase polymerization of olefins including a gas distribution grid installed in a lower part of the fluidized-bed reactor and a gas recycle line, which is equipped with a compressor and a heat exchanger and which is connected at the upper end with the top of the fluidized-bed reactor, wherein the gas recycle line splits at the lower end in at least two horizontal branches which are connected tangentially with the fluidized-bed reactor below the gas distribution grid and a process for preparing an olefin polymer carried out in the fluidized-bed reactor.

Abstract: A process for preparing an ethylene polymer in a suspension polymerization including the steps of separating the formed suspension of ethylene polymer particles in a solid-liquid separator into wet ethylene polymer particles and mother liquor, drying the wet ethylene polymer particles by a gas stream and forming a gas stream carrying a hydrocarbon load, and thereafter separating the hydrocarbon load from the gas stream and thereby forming a liquid hydrocarbon recover stream, transferring a part of the mother liquor into a work-up section including an evaporator for producing a wax-depleted portion of the mother liquor and a diluent distillation unit for producing isolated diluent from the wax-depleted portion of the mother liquor, wherein a first part of the hydrocarbon recover stream is transferred to the diluent distillation unit without passing the evaporator for producing the wax-depleted portion of the mother liquor.

Abstract: A process for preparing an ethylene polymer in a suspension polymerization including the steps of separating the formed suspension of ethylene polymer particles in a solid-liquid separator into wet ethylene polymer particles and mother liquor, transferring a part of the mother liquor into a work-up section including an evaporator for producing a wax-depleted portion of the mother liquor, a diluent distillation unit for producing isolated diluent from the wax-depleted portion of the mother liquor, and a wax removal unit operated by direct steam distillation for producing a gaseous hydrocarbon/steam mixture which is condensed and then separated into an aqueous phase and a hydrocarbon phase, wherein a first part of the hydrocarbon phase is transferred to the diluent distillation unit without passing the evaporator for producing the wax-depleted portion of the mother liquor.

Abstract: A process for polymerizing ethylene in a high-pressure polymerization system having a continuously operated polymerization reactor and a reactor blow down system having an emergency valve, a reactor blow down vessel containing an aqueous medium and a reactor blow down dump vessel, wherein the process includes the steps of monitoring the polymerization system for a disturbance, opening the emergency valve when a disturbance occurs to allow the content of the polymerization system to expand into the reactor blow down vessel, contacting the content of the polymerization system in the reactor blow down vessel with the aqueous medium to obtain an aqueous polymer slurry, separating the polymer slurry and gaseous components, and transferring the polymer slurry to the reactor blow down dump vessel.

Abstract: A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) a density from 0.945 to 0.958 g/cm3, determined according to ISO 1183 at 23° C.; 2) a ratio MIF/MI10 from 2 to 10; 3) a ?0.02 from 200,000 to 800,000 Pa·s; 4) a LCBI equal to or lower than 0.80; and 5) a ratio (?0.02/1000)/LCBI equal to or greater than 350.

Abstract: A polyolefin composition made from or containing (a) a polyolefin and (b) a gibbsite nano platelet treated with a compound of formula (ORa)3Si—Rb or of formula Rc—COOH wherein Ra is a C1-C10 alkyl radical; Rb is a C5-C30 alkyl radical and Rc is a C5-C30 hydrocarbon radical.

Abstract: A process for preparation of an ethylene polymer in a gas-phase polymerization unit comprising a gas-phase polymerization reactor by homopolymerizing ethylene or copolymerizing ethylene and one or more C4-C12-1-alkenes in a reaction gas made from or containing propane as polymerization diluent in the presence of a pre-activated polymerization catalyst, wherein a purified propane feed stream made from or containing at least 99 mol % propane and from 0.1 to 100 ppm mol propylene is fed to the gas-phase polymerization unit.

Abstract: A process for the preparation of ethylene homopolymers or copolymers in a facility having a high-pressure tubular reactor and a preheater, wherein a reaction fluid introduced into the reactor at a reactor inlet is heated in the preheater and the average velocity of the reaction fluid in the preheater is lower than the average velocity of the reaction fluid in the tubular reactor and the ratio of the average velocity in the tubular reactor to the average velocity of the reaction fluid in the preheater is in the range from 1.5 to 5.

Abstract: A method for aligning a cutter plate in a pelletizer for polymer pellets using a remote alignment adjustment device having a mechanical distance measurement probe and a camera for taking photos or videos. The remote alignment adjustment device is attached to the drive shaft of the cutter plate and rotates with the shaft to correct the alignment in different positions of the die plate. Additionally, a process for preparing polyethylene pellets in a pelletizer using the method for aligning the cutter plate.

Abstract: A process for continuously preparing a polyolefin composition made from or containing a polyolefin and carbon black in an extruder device. The process includes the steps of supplying polyolefin in form of a polyolefin powder and carbon black to a mixing device; alternatively, (a) measuring the flow rate of the polyolefin powder supplied to the mixing device or (b) measuring the flow rate of the polyolefin pellets prepared in the extruder device; adjusting the flow rate of the carbon black to the mixing device in response to the measured flow rate of the polyolefin powder or adjusting the flow rate of the polyolefin powder to the mixing device in response to the measured flow rate of the polyolefin pellets; melting and homogenizing the mixture within the extruder device; and pelletizing the polyolefin composition into the polyolefin pellets.

Abstract: A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) a density from 0.945 to 0.958 g/cm3, determined according to ISO 1183 at 23° C.; 2) a ratio MIF/MI10 from 2 to 10; 3) a ?0.02 from 200,000 to 800,000 Pa·s; 4) a LCBI equal to or lower than 0.80; and 5) a ratio (?0.02/1000)/LCBI equal to or greater than 350.