Borealis Technology Oy

Norner Verdandi As

Borealis Ag

Evonik Oxeno Gmbh

Evonik Degussa Gmbh

Norner As

Tore Dreng

Anneli Pakkanen

Michael Grass

Magnus Palmlöf

Jeroen Oderkerk

Markku Vahteri

Bill Gustafsson

Arild Follestad

Siw Bodil Fredriksen

Marja Mustonen

Jarmo Lindroos

Stefan Buchholz

Andrey Buryak

Esa Kokko

Alexander Krajete

Petri Rekonen

Vidar Almquist

Morten Lundquist

Espen Ommundsen

Janne Maaranen

Susana Filipe

Katrin Nord-Varhaug

Albrecht Dix

Ted M Pettijohn

Christian Piel

Pal Christian Bentzrod

Gerhard Ellermann

Philipp Walter

Ayodele Olutayo Fiola

Lars Hojer

Magnus Palmlof

John Severn

Ted Pettijohn

Pal Bentzrod

Jeanette Aumo

The present invention provides a process for the preparation of a multimodal polyethylene comprising: (i) polymerising ethylene and optionally an &#x3b1;-olefin comonomer in a first polymerisation stage to produce a first ethylene polymer; and (ii) polymerising ethylene and optionally an &#x3b1;-olefin comonomer, in the presence of said first ethylene polymer, in a second polymerisation stage, wherein the first and second polymerisation stages are carried out in the presence of an unsupported metallocene catalyst and each polymerisation stage produces at least 5% wt of the multimodal polyethylene, and the multimodal polyethylene has a multimodal molecular weight distribution, a molecular weight of at least 50,000 g/mol and a bulk density of at least 250 g/dm, and wherein a solution of the unsupported metallocene catalyst in a solvent is employed. The present invention also provides a multimodal polyethylene, a process for preparing a pipe comprising preparing a multimodal polyethylene and extruding the multimodal polyethylene to produce a pipe, and a pipe obtained by such a process.

Polyethylene for pipes

The present invention provides a process for the preparation of a multimodal polyethylene comprising: (i) polymerizing ethylene and optionally an &#x3b1;-olefin comonomer in a first polymerization stage to produce a first ethylene polymer; and (ii) polymerizing ethylene and optionally an &#x3b1;-olefin comonomer, in the presence of said first ethylene polymer, in a second polymerization stage, wherein the first and second polymerization stages are carried out in the presence of an unsupported metallocene catalyst and each polymerization stage produces at least 5% wt of the multimodal polyethylene, and the multimodal polyethylene has a multimodal molecular weight distribution, a molecular weight of at least 50,000 g/mol and a bulk density of at least 250 g/dm, and wherein a solution of the unsupported metallocene catalyst in a solvent is employed. The present invention also provides a multimodal polyethylene, a process for preparing a pipe comprising preparing a multimodal polyethylene and extruding the multimodal recycle polyethylene to produce a pipe, and a pipe obtained by such a process.

A peroxide crosslinked ethylene polymer pressure pipe and a method for the preparation thereof are described. The pipe is characterized in that it comprises an ethylene polymer with a density of less than 950 kg/mobtained by polymerization with a single-site catalyst and having a shear thinning index, SHIof less than 20 and a MWD of &#x3c;10. The method is characterized in that it comprises polymerizing ethylene, optionally together with at least one comonomer, with a single-site catalyst to provide the above defined ethylene polymer, forming the ethylene polymer into a pipe by extrusion and crosslinking it.

Peroxide crosslinked ethylene polymer pressure pipe and a method for the preparation thereof

A polyethylene moulding composition having a multimodal molecular weight distribution, having a density according to ISO 1183 at 23&#xb0; C. in the range of 920 to 960 kg/mand an MFR190/2 according to ISO 1133 in the range of 0.05 to 10 g/10 min, said polyethylene moulding composition comprising at least three ethylene polymer fractions having distinct molecular weights: A) 15 to 50 wt % of a low molecular weight ethylene homopolymer or copolymer fraction with a weight average molecular weight Mw in the range of 15 to 40 kg/mol; B) 15 to 50 wt % of a medium molecular weight ethylene homopolymer or copolymer fraction with a weight average molecular weight Mw in the range of 70 to 200 kg/mol; and C) 15 to 50 wt % of a high molecular weight ethylene homopolymer or copolymer fraction with a weight average molecular weight Mw in the range of 220 to 400 kg/mol, provided that one of A, B and C is an ethylene homopolymer and at least one other component is an ethylene copolymer with at least one C-Ccomonomer; and wherein the composition has&#x2014;a Shore D hardness measured according to ASTM D2240-05 (15 sec) of at least 56.0.

Moulding composition

An alkene interpolymer is prepared by polymerizing at least one 3-substituted Calkene and at least one Calkene in a gas phase polymerization using a polymerization catalyst system.

Polyolefin gas phase polymerization with 3-substituted C4-10-alkene

The invention provides a process for the preparation of a supported polymerization catalyst, said process comprising impregnating a porous particulate support in a mechanically fluidized state with a catalyst material.

Supported polymerization catalysts

A polyethylene produced by the homopolymerisation of ethylene or copolymerisation of ethylene with &agr;-olefins in the presence of a catalyst, characterized in that the fraction of low molecular weight polymers having MW<5000 g/mole is lower than 12% by weight of the produced polymer, and that the produced polyethylene has a measured melt strength expressed by a haul-off (HO) value satisfying the expression: HO>K &middot;&eegr;0.05&plus;K , wherein K is 9.10 and K is 0.4.

Polyethylenes obtained by use of dual site catalyst

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Larvik, Norway

Tore Dreng