Catalyst for olefin polymerization and a method for the manufacture thereof
AssigneeBorealis A/S
InventorsHarri Hokkanen, Hilkka Knuuttila, Eeva-Liisa Lakomaa, Pekka Sormunen
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AssigneeBorealis A/S
InventorsHarri Hokkanen, Hilkka Knuuttila, Eeva-Liisa Lakomaa, Pekka Sormunen
Estimating the term…
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.
A method for preparing a heterogeneous catalyst comprising at least one metallocene compound of a metal selected from the group consisting of Zr, Ti and Hf, on a solid inorganic support, comprising:
A method for preparing a heterogenous catalyst comprising at least one metallocene compound of a metal selected from the group consisting of Zr, Ti and Hf on a solid inorganic support, comprising:
Dependencies are inferred from the claim text.