Abstract: A polyethylene composition particularly suited for producing blow-molded hollow articles, having the following features: 1) density from more than 0.955 to 0.965 g/cm3; 2) ratio MIF/MIE from 60 to 125; 3) MIF from 15 to 40 g/10 min.; 4) ER values from 3.0 to 5.5; 5) 110.02 equal to or lower than 150,000 Pa·s.

Abstract: A polyethylene composition particularly suited for producing blow-molded hollow articles, having the following features: 1) density from 0.948 to 0.960 g/cm3; 2) ratio MIF/MIE greater than 125; 3) MIF from 20 to 40 g/10 min.; 4) ER values from 5 to 10.

Abstract: A polyethylene composition particularly suited for producing blow-molded hollow articles, having the following features: 1) density from 0.948 to 0.955 g/cm3; 2) ratio MIF/MIE from 60 to 120; 3) MIF from 15 to 45 g/10 min.; 4) ER values from 2 to 5.0; said composition being obtainable by contacting a precursor polyethylene composition with a radical initiator.

Abstract: A polyethylene composition for producing blown films, made from or containing an ethylene homopolymer or copolymer A) and an ethylene copolymer B) having a MIE value lower than the MIE value of A), the composition having the following features: 1) density from 0.948 to 0.960 g/cm3; 2) ratio MIF/MIP from 20 to 40; 3) MIF from 6 to less than 15 g/10 min.; 4) HMWcopo index from 0.5 to 3.5; 5) long-chain branching index, LCBI, equal to or lower than 0.82; 6) ?0.02 of equal to or less than 150000.

Abstract: Methods for processing polyolefin recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. polyolefin recyclate feedstocks can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed polyolefin recyclates. Processed polyolefin recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both polyolefin recyclate and/or pre-consumer polyolefins.

Abstract: Methods for processing LDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. LDPE recyclate can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed LDPE recyclates. Processed LDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both LDPE recyclate and/or pre-consumer polyolefins.

Abstract: Methods for processing HDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. HDPE recyclate can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed HDPE recyclates. Processed HDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both HDPE recyclate and/or pre-consumer polyolefins.

Abstract: Methods for processing HDPE and/or MDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. HDPE and/or MDPE recyclate feedstocks can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed HDPE recyclate and/or processed MDPE recyclates. Processed HDPE recyclate and/or processed MDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both HDPE and/or MDPE recyclate and/or pre-consumer polyolefins.

Abstract: Methods for processing LLDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. LLDPE recyclate can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed LLDPE recyclates. Processed LLDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both LLDPE recyclate and/or pre-consumer polyolefins.

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: 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 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 polyethylene composition for producing blown films, made from or containing an ethylene homopolymer or copolymer A) and an ethylene copolymer B) having a MIE value lower than the MIE value of A), the composition having the following features: 1) density from 0.948 to 0.960 g/cm3; 2) ratio MIF/MIP from 20 to 40; 3) MIF from 6 to less than 15 g/10 min.; 4) HMWcopo index from 0.5 to 3.5; 5) long-chain branching index, LCBI, equal to or lower than 0.82; 6) ?0.02 of equal to or less than 150000.

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 gas-phase polymerization reactor for the gas-phase polymerization of olefins including a polymerization zone having a recycle line for (a) withdrawing reaction gas from the reactor, (b) leading the reaction gas through a heat-exchanger for cooling, and (c) feeding the reaction gas back to the reactor, wherein the recycle line has the heat-exchanger, a centrifugal compressor having variable guide vanes, and a butterfly valve, and a related process for preparing an olefin polymer in the gas-phase polymerization reactor.

Abstract: A gas-phase polymerization reactor for the gas-phase polymerization of olefins including a polymerization zone having a recycle line for (a) withdrawing reaction gas from the reactor, (b) leading the reaction gas through a heat-exchanger for cooling, and (c) feeding the reaction gas back to the reactor, wherein the recycle line has the heat-exchanger, a centrifugal compressor having variable guide vanes, and a butterfly valve, and a related process for preparing an olefin polymer in the gas-phase polymerization reactor.

Abstract: Process for preparing an olefin polymer including the step of polymerizing an olefin in the presence of a polymerization catalyst and hydrogen as molecular weight regulator in a gas-phase polymerization reactor to yield growing polymer particles, the reactor including three or more polymerization zones and at least two thereof are sub-zones of a polymerization unit wherein the growing polymer particles flow downward in a densified form and at least one polymerization zone has a ratio of hydrogen to the sum of olefins which is a factor of at least 1.5 lower than the ratio of hydrogen to the sum of olefins in the polymerization zone having the highest ratio of hydrogen to the sum of olefins and a factor of at least 1.5 higher than the ratio of hydrogen to the sum of olefins in the polymerization zone having the lowest ratio of hydrogen to the sum of olefins.

Abstract: A process for preparing an ethylene polymer including the step of homopolymerizing ethylene or copolymerizing ethylene with one or more comonomers in a gas-phase polymerization reactor including a riser unit wherein growing polymer particles flow upwards under fluidization, fast fluidization or transport conditions and a downcomer wherein growing polymer particles flow downward in a densified form, wherein the hold-up of polymer particles in the downcomer is from 55 wt. % to 80 wt. % of the total hold-up of polymer particles in the gas-phase polymerization reactor.

Abstract: A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) density from 0.948 to 0.952 g/cm3 determined according to ISO 1183-1 at 23° C.; 2) ratio MIF/MIP from 12 to 25; 3) MIF from 18 to 40 g/10 min.; 4) Mz equal to or greater than 1,200,000 g/mol; 5) ?0.02 from 35,000 to 55,000 Pa·s; 6) long-chain branching index, LCBI, equal to or greater than 0.55; and 7) ratio (?0.02/1000)/LCBI from 55 to 75.