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 ethylene polymer particles and mother liquor, transferring a first part of the mother liquor into a work-up section including an evaporation unit for producing a wax-depleted portion of the mother liquor, wherein a protic agent is added to the part of the mother liquor which is transferred into the work-up section, and recycling a first part of the wax-depleted portion of the mother liquor to the polymerization reactor or the series of polymerization reactors.

Abstract: A polyethylene composition made from or containing: A) from 75% to 97% by weight of a copolymer of ethylene having: 1) a density of 0.925 g/cm3 or higher; and 2) a MI2 value of 0.5 g/10 min. or greater; and B) from 3% to 25% by weight of a polyolefin composition made from or containing: BI) from 5% to 35% by weight of a propylene homopolymer or a propylene copolymer; BII) from 20% to 50% by weight of a copolymer of ethylene containing from 1.0% to 20.0% by weight of alpha-olefin units and 25.0% by weight or less of a fraction soluble in xylene at 25° C.; and BIII) from 30% to 60% by weight of a copolymer of ethylene and propylene containing from 25.0% to 75.0% by weight of ethylene derived units and from 40.0% to 95.0% by weight of a fraction soluble in xylene at 25° C.

Abstract: An apparatus for carrying out a gas-phase olefin polymerization having a first polymerization zone having a cylindrical segment of diameter D01, a second polymerization zone having a cylindrical upper part of diameter D05 and a cylindrical lower part of diameter D06, a separation zone of diameter D04, a first connecting element of diameter D03, which is a bend of radius R03 or has a bend part of radius R03, a gas recycle line of diameter D08, a transition segment of diameter D02, and a second connecting element of a diameter D09, which is a bend or has a bend part, wherein the ratio D04 to D05 is 1.0 to 1.5, the ratio D05 to D06 is 1.2 to 2, the ratio R03 to D03 is 1 to 6, the ratio D03 to D01 is 0.3 to 0.85, and the ratio D08 to D02 is 1.0 to 2.2.

Abstract: A process for preparing ethylene polymers including the step of polymerizing ethylene or copolymerizing ethylene and one or more comonomers at a temperature from 100° C. to 350° C. and a pressure of from 110 MPa to 350 MPa in a continuously operated tubular polymerization reactor, thereby yielding a reaction mixture, wherein the tubular polymerization reactor has a reactor cooling jacket for removing the heat of the reaction and a pressure control valve, the reaction mixture leaves the reactor through the pressure control valve, the reaction mixture then passes a post-reactor cooler equipped with a post-reactor cooling jacket, the reactor cooling jacket is provided with a reactor coolant having an inlet temperature and the post-reactor cooling jacket is provided with a post-reactor coolant having an inlet temperature, and the inlet temperature of the post-reactor coolant is independently controlled from the inlet temperature of the reactant coolant.

Abstract: Method for the preparation of dried polymer pellets in a facility having a dryer with a first chamber and a mechanical agitator, and the facility further having a degassing silo with a second chamber, the method includes the steps of guiding a drying gas flow made from or containing a first gas mixture for drying wet polymer pellets into the first chamber, transferring the dried polymer pellets into the second chamber, guiding a second gas mixture for degassing the dried polymer pellets into the second chamber thereby transforming the second gas mixture into a third gas mixture and guiding a portion of the third gas mixture into the first chamber; and process for manufacturing LDPE pellets.

Abstract: Apparatus for carrying out a catalytic gas-phase olefin polymerization having a first polymerization zone for growing polymer particles to flow upward under fast fluidization or transport conditions, a second polymerization zone for the growing polymer particles to flow downward, and a gas/solid separation zone; wherein the second polymerization zone has an upper part being connected to the separation zone and a lower part being connected to the upper part; wherein the ratio of the height H01 of the separation zone to the diameter D01 of the separation zone is 2.5 to 4.5.

Abstract: A polyethylene composition for preparing filaments and fibers, made from or containing: A) from 65% to 97% by weight of a copolymer of ethylene having: 1) a density of 0.925 g/cm3 or higher; and 2) a MI2 value of 0.5 g/10 min. or greater; and B) from 3% to 35% by weight of a polyolefin composition made from or containing: BI) from 5% to 35% by weight of a propylene homopolymer; BII) from 20% to 50% by weight of an ethylene homopolymer or a copolymer of ethylene with up to 5% by weight of alpha-olefin comonomers, containing 5% by weight or less of a fraction soluble in xylene at 25° C.; and BIII) from 30% to 60% by weight of a terpolymer of ethylene, propylene, and 1-butene containing from 30% to 85% by weight of a fraction soluble in xylene at 25° C.

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.