PROCESS FOR PRODUCING A POLYMER COMPOSITION

• Main Authors: AHO, Jani, GALGALI, Girish Suresh, BERGER, Friedrich
• Format: Patent
• Language: English; French; German
• Published: 25.05.2022
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

The present invention concerns a process for producing a polymer composition characterized in that a first ethylene polymer component (A) is obtained in a first polymerization zone by polymerization conducted in slurry in the presence of ethylene, optionally at least one comonomer selected from alpha-olefins having from 4 to 10 carbon atoms and optionally hydrogen and a second ethylene polymer component (B) is obtained in a second polymerization zone by polymerization conducted in slurry in the presence of ethylene, first ethylene polymer component (A), optionally at least one comonomer selected from alpha-olefins having from 4 to 10 carbon atoms and optionally hydrogen and a third ethylene polymer component (C ) is obtained in a third polymerization zone by polymerization conducted in gas phase in the presence of ethylene, optionally hydrogen and at least one comonomer selected from alpha-olefins having from 4 to 10 carbon atoms, to produce a multimodal polymer of ethylene (a) with at least one comonomer selected from alpha-olefins having from 4 to 10 carbon atoms, - which has a) a density between 900 and 960 kg/m3 b) MFR2 of 0.1 to 25 g/10 min (according to ISO 1133 at 190°C under 2.16 kg load), c) MWD of 2 to 6, - which comprises at least - between 10 to < 25 wt% of an ethylene polymer component (A), - between 10 to < 25 wt% of an ethylene polymer component (B) and - between > 50 and 80 wt% of an ethylene polymer component (C) and wherein the densities of ethylene polymer components (A) and (B) are each between 925 and 970 kg/m3 and the density of ethylene polymer component (C) has a density between 880 and 950 kg/m3, wherein further the ethylene polymer components (A), (B) and (C) have different MFR2 values.