Borealis AG

Process for the production of a polypropylene random copolymer (PP), the process comprising the steps of polymerising in a first reactor (R1) propylene and a comonomer (C1a) selected from a C 4 to C 8 α-olefin in the presence of a first metallocene catalyst (MC1) yielding a first polypropylene copolymer (PP1), wherein the ratio of the feed of the comonomer (C1 a ) to the feed of propylene is in the range of 1 to 100 mol/kmol and the MFR 2 of the first polypropylene copolymer (PP1) is in the range of 0.01 to 100 g/10 min; transferring the first polypropylene copolymer (PP1) to a second reactor (R2); polymerising in the second reactor (R2) and in the presence of said first polypropylene (PP1), propylene, a comonomer (C1 b ) selected from a C 4 to C 8 α-olefin, and a second metallocene catalyst (MC2) yielding a second polypropylene copolymer (PP2), wherein the ratio of the feed of the comonomer (C1 b ) to the feed of propylene is in the range of 40 to 150 mol/kmol and the MFR 2 of the second polypropylene copolymer (PP2) is in the range of 0.01 to 100 g/10 min; withdrawing the polypropylene random copolymer (PP) comprising the first polypropylene copolymer (PP1) and the second polypropylene copolymer (PP2) from the second reactor (R2); wherein the first metallocene catalyst (MC1) and/or the second metallocene catalyst (MC2) is a metallocene catalyst (MC) comprising a metallocene complex, and wherein the metallocene catalyst (MC) comprises a support comprising silica.

A process for the separation of at least one polyolefin from a product stream from a solution polymerization process, wherein the product stream comprises the at least one polyolefin and a mixture of volatiles, the process comprising the steps of separating the product stream into a first polyolefin-lean vapor stream and a first condensed polyolefin-rich stream; separating the first condensed polyolefin-rich stream into a second polyolefin-lean vapor stream and a second condensed polyolefin-rich stream; separating the second condensed first condensed polyolefin-rich stream into a last polyolefin-lean vapor stream and a last condensed polyolefin-rich stream; characterized in that the first polyolefin-lean vapor stream and the second polyolefin-lean vapor stream are introduced into an initial feed stream of the solution polymerization process without any further purification step.

The disclosure relates to a polymerization process. The polymerization process comprises polymerizing an olefin monomer and a comonomer in the presence of a polymerization catalyst in a polymerization step conducted in a polymerization reactor in a solvent to produce a solution comprising a polymer of the olefin monomer and the comonomer. The polymerization process comprises withdrawing an exhaust stream of the solution from the polymerization reactor in a withdrawing step. The polymerization process comprises separating the exhaust stream to a first primary stream and a primary concentrated solution stream in a first primary separation step, wherein the first primary stream comprises hydrocarbons and polymer. The polymerization process comprises separating the first primary stream to a second primary stream and a third primary stream in a second primary separation step, wherein the second primary stream comprises dissolved polymer and the third primary stream comprises majority of the hydrocarbons. The polymerization process comprises cooling the third primary stream to a temperature of −80 to 20° C. in a primary cooling step to obtain a cooled third primary stream. The polymerization process comprises separating the cooled third primary stream to a fourth primary stream and a fifth primary stream in a third primary separation step, wherein the fourth primary stream comprises hydrocarbons in vapour phase and the fifth primary stream comprises liquid hydrocarbons. The polymerization process comprises returning the fourth primary stream and the fifth primary stream independently in a primary returning step to a location upstream of the polymerization reactor.

A gas phase polymerization assembly comprising a gas phase polymerization reactor having at least one inlet and at least one outlet, a circulation gas compression unit having an inlet and an outlet, whereby the inlet of the circulation gas compression unit is fluidly connected to the at least one outlet of the gas phase polymerization reactor by an unreacted gas line; a flush gas compression unit having an inlet and an outlet, wherein the inlet of the flush gas compression unit is fluidly connected to the outlet of the circulation gas compression unit by a pressurized unreacted gas line; a circulation line fluidly connecting the pressurized unreacted gas line with the at least one inlet of the gas phase polymerization reactor; a flush gas withdrawal line connected to the outlet of the flush gas compression unit.

The present invention relates to a process for producing of solid particulate olefin polymerisation catalyst or catalyst carrier comprising forming a solution of the catalyst or a catalyst carrier in a solvent, subjecting the solution into an atomization by spraying the solution via a capillary vibrating spray nozzle with a capillary orifice having a diameter of 5 to 100 μm generating a laminar jet of liquid, which disintegrates into liquid droplets entering into the spray-dryer, transforming the droplets with aid of a gas to solid particulate catalyst or carrier in the spray-dryer and recovering the solid particulate olefin polymerisation catalyst or carrier having particle size distribution defined by a volumetric SPAN of 0.7 or less. The invention further relates to the catalyst produced by the methods, and use thereof in olefin polymerisation process.

The disclosure relates to a process for polymerising olefins in multi stage polymerisation process configuration, the process comprising a) polymerising in a first polymerisation step ethylene, optionally in the presence of at least one other alpha olefin comonomer, in the presence of a polymerisation catalyst so as to form a first polymer component (A); and b) polymerising in a second polymerisation step in gas phase a predetermined monomer mixture comprising ethylene and 1-hexene, optionally in the presence of at least one other alpha olefin comonomer, in the presence of the first polymer component (A) of step a), so as to form a second polymer component (B), wherein the multimodal polyethylene polymer produced by the present process comprises 1-hexene comonomer and at least one further C4-10-comonomer, and wherein the predetermined monomer mixture comprising ethylene and 1-hexene is fed into the second polymerisation step from the beginning of its start up. The disclosure further relates to use of 1-hexene in a gas phase olefin polymerisation step for improving performance of single-site polymerisation catalyst in multi-stage olefin copolymerisation process. The disclosure still further relates to a method for improving performance of single-site polymerisation catalyst in a multi-stage olefin polymerisation comprising feeding a predetermined monomer mixture comprising ethylene and 1-hexene into the gas phase polymerisation step from the beginning of its start up.

A polyethylene (PE) for the production of crosslinked polyethylene (PEX), having a beneficial balance of unsaturation properties and processability properties, processes for producing crosslinked polyethylene (PEX) from said polyethylene (PE), and the crosslinked polyethylene (PEX) thus produced.

The disclosure relates to a process for polymerising olefins in multi stage polymerisation process configuration, comprising a) polymerising in a first polymerisation step first olefin monomer, optionally in the presence of at least one other alpha olefin monomer, in the presence of a polymerisation catalyst so as to form a first polymer component (A), and b) polymerising in a second polymerisation step in gas phase second olefin monomer, optionally in the presence of at least one other alpha olefin comonomer, in the presence of the first polymer component (A) of step a) and an induced swelling agent, so as to for a second polymer component (B), wherein the first polymer component (A) and the second polymer component (B) are produced at production rates meeting a predetermined target weight ratio of the second polymer component (B) to the first polymer component (A), the process comprising the steps of: i) determining a first weight ratio of the second polymer component (B) to the first polymer component (A) in the second polymerisation step, and ii) increasing the concentration of the induced swelling agent in the second polymerisation step if the determined first weight ratio is less than the predetermined target weight ratio, or iii) decreasing the concentration of the induced swelling agent in the second polymerisation step if the determined first weight ratio is greater than the predetermined target weight ratio, or iv) maintaining the concentration of the induced swelling agent in the second polymerisation step if the determined first weight ratio equals the predetermined target weight ratio. The disclosure further relates to use of an induced swelling agent in a gas phase polymerisation step for improving gas phase production split in a multi-stage olefin polymerisation process.

The disclosure relates to a process for polymerising olefins, the process comprising polymerising ethylene, optionally in the presence of at least one other alpha olefin comonomer, preferably C4-C10 alpha olefin comonomer, preferably in multi stage polymerisation process configuration, in the presence of a single-site polymerisation catalyst to produce a polymer component to produce a polyethylene polymer or a polyethylene copolymer, wherein the single-site polymerisation catalyst comprises (i) a transition metal complex; (ii) a cocatalyst; and optionally (iii) a support; and is characterised by a (Weibull modulus)×(scale parameter) product equal to or higher than 40 MPa and a (Weibull modulus)/(scale parameter) ratio equal to or lower than 0.50 MPa −1 wherein the Weibull modulus and the scale parameter are determined by the Weibull analysis of the compressive strength of the catalyst particles. The disclosure further relates to a single-site polymerisation catalyst, comprising (i) a transition metal complex; (ii) a cocatalyst; and optionally (iii) a support, preferably a silica support; wherein the single-site polymerisation catalyst is characterised by a (Weibull modulus)×(scale parameter) product equal to or higher than 40 MPa and a (Weibull modulus)/(scale parameter) ratio equal to or lower than 0.50 MPa −1 wherein the Weibull modulus and the scale parameter are determined by the Weibull analysis of the compressive strength of the catalyst particles. The disclosure further relates to use of the single-site polymerisation catalyst in the preparation of a polyethylene polymer component, a polyethylene polymer, or a polyethylene copolymer.

The disclosure relates to a process for polymerising olefins in multi stage polymerisation process configuration, the process comprising a) polymerising in a first polymerisation step first olefin monomer, optionally in the presence of at least one other alpha olefin comonomer, in the presence of a metallocene polymerisation catalyst so as to form a first polymer component (A); and b) transferring the first polymer component (A) into a separation unit to remove low molecule penetrants and to obtain separated solid polyolefin particles of the first polymer component (A*) and c) polymerising in in gas phase in a second polymerisation step second olefin monomer, optionally in the presence of at least one other alpha olefin comonomer in the presence of the separated solid polyolefin particles (A*) of step b), so as to form a second polymer component (B). The disclosure further relates to a method for improving performance of a metallocene polymerisation catalyst in a multi-stage olefin polymerisation, wherein a first polymer component (A) produced in a first polymerisation step is transferred into a separation unit to remove low molecule penetrants and to obtain separated solid polyolefin particles of the first polymer component (A*) prior to transferring the obtained separated solid polyolefin particles of the first polymer component (A*) to a further polymerisation step.