Borealis Technology Oy

Borealis A/s

Neste Oy

Harri Hokkanen

Hilkka R Knuuttila

Eeva-Liisa Lakomaa

Kalle Kallio

Pekka J Sormunen

Vidar Almquist

Suvi P Haukka

Pekka Knuuttila

Marina Lindblad

Eero I Iiskola

Arild Follestad

Marja Mustonen

Jukka Hietala

Outi Krause

Tuomo Suntola

Ole Jan Myhre

Ulf Palmqvist

Ove S Andell

Merete Skar

Hannu Salminen

Arja Lehtinen

Ari Palmroos

Lars Peter Lindfors

Eija Lappi

Arla Kyt&ouml;kivi

Eija Salo

Ingrid Sorum Melaaen

Tone Aastad

Esa Kinnunen

A particulate, modified chromium oxide catalyst for the polymerisation of ethylene or ethylene with &agr;-olefins, comprising: a) a chromium-oxide catalyst, b) a transition metal compound, and c) a catalyst activator. A method for the preparation of the catalyst comprises the steps of: a) subjecting a chromium oxide catalyst precursor, which comprises a chromium oxide compound combined with an inorganic support, to a temperature in the range of from 400 to 950&deg; C. under oxidising conditions, and b) impregnating the obtained chromium catalyst with a catalyst activator and with a transition metal compound which comprises at least one cyclopentadienylic ring bonded to said transition metal and at least ligand selected from the group comprising alkoxy, amido and hydrocarbyl radicals, halogen and hybride bonded to said transition metal, which cyclopentadienylic ring may contain hetero atoms, be unsubstituted or substituted, be bonded to said transition metal through a bridge, and optionally annealed to other substituted or unsubstituted ring structures, and if two cyclopentadienyl rings are present they may be bonded to each other through a bridge, and c) subjecting the thus obtained particulate catalyst to drying conditions. This catalyst is suitable for producing polyethylenes under conditions of continuous feeding of all reactants.

Catalyst for the (co)polymerization of ethylene and a method for the preparation thereof

This invention concerns process for producing polyethylene compositions, films prepared thereof and process for the preparation of the films. The process comprises subjecting ethylene, optionally hydrogen and comonomers to polymerization or copolymerization reactions in a multistage polymerization. At least one polymerization stage is conducted essentially in the absence of hydrogen. The polymerization reactions are carried out in the presence of a single-site catalyst capable of forming a composition comprising a low molecular weight component with MFR of at least 10 g/10 min and a density higher than the density of the composition and a high molecular weight component. The melt flow rate of the composition is in the range MFR &equals;0.1-5.0 g/10 min and the density of the composition is 915-960 kg/m . The invention makes it possible to produce polyethylene compositions for manufacturing films with a good balance between optical and mechanical properties.

Polymer composition, a process for the production thereof and films prepared thereof

The present invention concerns a method for preparing heterogeneous catalysts. According to the method, preparation is carried out under such process conditions in which the bonding of compounds from the gas phase onto the surface of a support material is primarily determined by the properties of the support surface. The constituents contained in the reagent are then selectively bonded to the bonding sites of the support material surface, thus forming stable surface bonds. According to the invention, the number of surface-bond sites available for preparing a stable product with surface bonds is controlled by varying the reaction temperature and/or selecting a suitable reagent. The invention makes it possible to control the metal content of the end product at a predetermined level.

Method for preparing heterogeneous catalysts of desired metal content

Method for preparing a catalyst component for homo or copolymerization of olefins, said catalyst component comprising at least one metallocene compound on porous inorganic carrier, wherein said metallocene compound is mixed as pure compound in the absence of solvents with said carrier at a temperature which is at least 50&deg; C. but below the vaporization temperature of the metallocene compound in reactor conditions for a sufficient time to obtain said catalyst component having said metallocene evenly distributed onto carrier particles.

Method for preparing catalyst components

A method for transitioning between two different catalysts in olefin polymerizations, a first catalyst and a second catalyst, comprising the steps of: discontinuing the feed of the first catalyst into the polymerization reactor, and introducing the second catalyst into the reactor, wherein the transition is performed between a chromium-based catalyst and a metallocene catalyst.

Method of catalyst transitions in olefin polymerizations

Olefin polymerization catalyst system, producing and using it

Provided are heterogeneous catalysts for homo- and copolymerization of olefins as well as a method for preparing these catalysts, which comprise at least one metallocene compound of a Group 4A, 5A or 6A (Hubbard) transition metal on a solid inorganic support. The method comprises the steps of vaporizing the metallocene compound, treating the support material with the vaporized metallocene compound at a temperature which is sufficiently high to keep the metallocene compound in the vaporous state, contacting the support material with an amount of the vaporized metallocene compound which is sufficient to allow for a reaction between the metallocene compound and at least a substantial part of the available surface sites capable of reacting therewith, removing the rest of the metallocene compound not bound to the support, and optionally treating the product thus obtained with an activating agent. The catalysts are active even if very low amounts of activator agents, such as alumoxane, are used. Furthermore, the polymerization performance of the catalysts can be regulated during the preparation of the catalysts. Thus, by using different support pretreatment temperatures, or by using two or more different metallocenes, and by altering the order in which they are added on the support, it is possible to control and regulate the activity of the catalysts and the polymer properties, such as molecular weight and molecular weight distribution.

Catalyst for olefin polymerization and a method for the manufacture

Process for manufacturing LLDPE polymers

The present invention concerns heterogeneous catalysts for polymerization of olefins. The catalysts include at least one Group IVa metal compound on a solid inorganic oxidic support. According to the invention the catalysts are prepared by vapourizing at least one solid Group IVa metal halide compound and routing the vapour of the metal halide compound into a reaction chamber, wherein the vapour is reacted with the support at a temperature of about 250.degree. to about 450.degree. C. in order to bind said metal halide compound to said support. Any metal compound not bound to said support as well as any volatile reaction products emanating from the reaction between said metal halide compound and said support are then removed from the reaction chamber in the vapour phase. Optionally, the product obtained is treated with an organic aluminum compound to increase the catalytic activity of said catalyst. The catalysts thus prepared are very well suited for polymerization of ethylene or copolymerization of ethylene with other alpha-olefins, such as propylene, butylene, 4-methyl-1-pentene and hexene. A polymerization process employing the novel catalyst will provide products of the Ultra High Molecular Weight-type (UHMWPE) having very broad MWD.

Catalyst for polymerization of ethylene

Provided are heterogeneous catalysts for homo- and copolymerization of olefins as well as a method for preparing these catalysts, which comprise at least one metallocene compound of a Group 4A, 5A or 6A (Hubbard) transition metal on a solid inorganic support. The mtehod comprises the steps of vaporizing the metallocene compound, treating the support material with the vaporized metallocene compound at a temperature which is sufficiently high to keep the metallocene compound in the vaporous state, contacting the support material with an amount of the vaporized metallocene compound which is sufficient to allow for a reaction between the metallocene compound and at least a substantial part of the available surface sites capable of reacting therewith, removing the rest of the metallocene compound not bound to the support, and optionally treating the product thus obtained with an activating agent. The catalysts are active even if very low amounts of activator agents, such as alumoxane, are used. Furthermore, the polymerization performance of the catalysts can be regulated during the preparation of the catalysts. Thus, by using different support pretreatment temperatures, or by using two or more different metallocenes, and by altering the order in which they are added on the support, it is possible to control and regulate the activity of the catalysts and the polymer properties, such as molecular weight and molecular weight distribution.

Growing community of inventors

Helsinki, Finland

Harri Hokkanen