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US 10,577,490 B2Granted
Polyethylene composition having high mechanical properties and processability
AssigneeBasell Polyolefine GmbH
InventorsIakovos Vittorias, Bernd Lothar Marczinke, Gerhardus Meier, Ulf Schüller, Andreas Maus, Harilaos Mavridis, Diana Dötsch
Life of this patent
Estimating the term…
Abstract
A polyethylene composition having the following features: 1) density from about 0.945 to about 0.955 g/cm3, determined according to ISO 1183 at 23° C.; 2) ratio MIF/MIP from about 23 to about 40; 3) MIF from about 8.5 to about 18 g/10 min.; 4) HMWcopo index from about 3.5 to about 20; and 5) long-chain branching index, LCBI, equal to or greater than about 0.45. The polyethylene composition can be used to produce pipes and films.
Claims10
A polyethylene composition comprising:
- an ethylene polymer, wherein the ethylene polymer has a melt flow index (MIE) of 50 to 110 g/10 min., measured at 190° C. with a load of 2.16 kg, and wherein the polyethylene composition has:
- 1) a density from about 0.945 to about 0.955 g/cm3, determined according to ISO 1183 at 23° C.;
- 2) a ratio MIF/MIP from about 23 to about 40, where MIF is the melt flow index at 190° C. with a load of 21.60 kg, and MIP is the melt flow index at 190° C. with a load of 5 kg, both determined according to ISO 1133;
- 3) a MIF from about 8.5 to about 18 g/10 min.;
- 4) a HMWcopo index from about 3.5 to about 20;
- and
- 5) a long-chain branching index, LCBI, equal to or greater than about 0.45;
- wherein the HMWcopo index is determined according to the following formula:
- HMWcopo=(η0.02×tmaxDSC)/(10{circumflex over ( )}5)
- where
- η0.02 is the complex viscosity of a melt in Pa·s, measured at a temperature of 190° C., in a parallel-plate rheometer under dynamic oscillatory shear mode with an applied angular frequency of 0.02 rad/s;
- (ii) tmaxDSC is the time in minutes to reach the maximum value of heat flow of crystallization at a temperature of 124° C. under quiescent conditions, measured in isothermal mode in a differential scanning calorimetry apparatus;
- and
- (iii) LCBI is the ratio of the measured mean-square radius of gyration Rg, measured by GPC-MALLS, to the mean-square radius of gyration for a linear PE having a molecular weight equal to about the molecular weight of the polyethylene composition.
11 more elements
An article of manufacture comprising:
- a polyethylene composition comprising
- an ethylene polymer, wherein the ethylene polymer has a melt flow index (MIE) of 50 to 110 g/10 min., measured at 190° C. with a load of 2.16 kg, and wherein the polyethylene composition has:
- 1) a density from about 0.945 to about 0.955 g/cm3, determined according to ISO 1183 at 23° C.;
- 2) a ratio MIF/MIP from about 23 to about 40, where MIF is the melt flow index at 190° C. with a load of 21.60 kg, and MIP is the melt flow index at 190° C. with a load of 5 kg, both determined according to ISO 1133;
- 3) a MIF from about 8.5 to about 18 g/10 min.;
- 4) a HMWcopo index from about 3.5 to about 20;
- and
- 5) a long-chain branching index, LCBI, equal to or greater than about 0.45;
- wherein the HMWcopo index is determined according to the following formula:
- HMWcopo=(η0.02×tmaxDSC)/(10{circumflex over ( )}5)
- where
- (i) η0.02 is the complex viscosity of a melt in Pa·s, measured at a temperature of 190° C., in a parallel-plate rheometer under dynamic oscillatory shear mode with an applied angular frequency of 0.02 rad/s;
- (ii) tmaxDSC is the time in minutes to reach the maximum value of heat flow of crystallization at a temperature of 124° C. under quiescent conditions, measured in isothermal mode in a differential scanning calorimetry apparatus;
- and
- (iii) LCBI is the ratio of the measured mean-square radius of gyration Rg, measured by GPC-MALLS, to the mean-square radius of gyration for a linear PE having a molecular weight equal to about the molecular weight of the polyethylene composition.
12 more elements
A process for preparing a polyethylene composition comprising:
- polymerization steps carried out in the presence of a Ziegler-Natta polymerization catalyst supported on MgCl2, wherein
- the polyethylene composition comprises
- an ethylene polymer, wherein the ethylene polymer has a melt flow index (MIE) of 50 to 110 g/10 min., measured at 190° C. with a load of 2.16 kg, and wherein the polyethylene composition has:
- 1) a density from about 0.945 to about 0.955 g/cm3, determined according to ISO 1183 at 23° C.;
- 2) a ratio MIF/MIP from about 23 to about 40, where MIF is the melt flow index at 190° C. with a load of 21.60 kg, and MIP is the melt flow index at 190° C. with a load of 5 kg, both determined according to ISO 1133;
- 3) a MIF from about 8.5 to about 18 g/10 min.;
- 4) a HMWcopo index from about 3.5 to about 20;
- and
- 5) a long-chain branching index, LCBI, equal to or greater than about 0.45;
- wherein the HMWcopo index is determined according to the following formula:
- HMWcopo=(η0.02×tmaxDSC)/(10{circumflex over ( )}5)
- where
- (i) η0.02 is the complex viscosity of a melt in Pa·s, measured at a temperature of 190° C., in a parallel-plate rheometer under dynamic oscillatory shear mode with an applied angular frequency of 0.02 rad/s;
- (ii) tmaxDSC is the time in minutes to reach the maximum value of heat flow of crystallization at a temperature of 124° C. under quiescent conditions, measured in isothermal mode in a differential scanning calorimetry apparatus;
- and
- (iii) LCBI is the ratio of the measured mean-square radius of gyration Rg, measured by GPC-MALLS, to the mean-square radius of gyration for a linear PE having a molecular weight equal to about the molecular weight of the polyethylene composition.
13 more elements
Dependencies are inferred from the claim text.