Abstract: Alumoxanes having C2-C12 alkyl groups can conveniently be used in supported olefin polymerization catalyst compositions prepared by contacting, either previous to or immediately before the beginning of the olefin polymerization, a support comprising a porous carrier with (a) an organometallic compound of the general formula R1MXv−1, (b) a metallocene of the general formula (CpY)mM′X′nZo and an alumoxane of the following general formula in any order.

Abstract: 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 MFR2 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 MFR2=0.1-5.0 g/10 min and the density of the composition is 915-960 kg/m3. The invention makes it possible to produce polyethylene compositions for manufacturing films with a good balance between optical and mechanical properties.

Abstract: Rotational moulding process for polymerizing or copolmerizing ethylene for manufacturing ethylene polymers or copolymers having a controlled particle size and morphology. Ethylene is polymerized or copolymerized under ethylene polymerizing conditions in the presence of a supported metallocene catalyst, where the average particle size of the catalyst particles is selected within the range of 14-40 &mgr;m and the residence time at the polymerization is selected so as to achieve a polymer where average particle size is between 0.2-0.5 mm and the proportion of fractions between 0.1-0.6 is at least 80%.

Abstract: The invention relates to a process and to an apparatus for preparing a heterogeneous catalyst having at least one catalytically active species bound to the surface of a support material. According to the process, the surface of the support is first pretreated. A catalyst reagent containing the catalytically active species or its precursor is vaporized and the vapor is routed into a reaction chamber where it is brought to interact with the support material. The catalyst reagent not bound to the support is withdrawn from the reaction chamber in gaseous form. If necessary, the species bound to the support is posttreated in order to convert it into a catalytically active form. According to the invention, the amount of catalyst reagent brought into the reaction chamber is at least equal to, preferably in excess of the number of available binding sites on the surface.

Abstract: 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.

Abstract: 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° 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.

Abstract: Aluminoxanes having C2-C10 alkyl groups can conveniently be used in supported olefin polymerization catalyst compositions prepared by contacting a support comprising a solid compound which is one of pure aluminium oxide, a mixed aluminium oxide, an aluminium salt, a magnesium halide, or a C1-C8 alkoxy magnesium halide, in any order with at least a) an organometallic compound, b) a metallocene, and c) an aluminoxane, and recovering said supported olefin polymerization catalyst composition.

Abstract: The invention relates to metallocene compounds having the formula (I): (CpYq)mMRnBo  (I) wherein: Cp or each same or different Cp is a non-substituted or substituted, fused or non-fused, homo(iso)cyclic or heterocyclic cyclopentadienyl ligand, indenyl ligand, tetrahydroindenyl ligand, fluorenyl ligand or octahydrofluorenyl ligand, Y or each same or different Y is a substituent at the cyclopentadienyl ring of said ligand Cp having the following structure (II): wherein: D is an element of Group 14 of the Periodic Table (IUPAC), R1, R2 and R3 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure; M is a transition metal of Group 4 of the Periodic Table (IUPAC) and is bound to the ligand Cp or ligands Cp in an &eegr;5 bonding mode; R or each same o

Abstract: The present invention relates to an olefin polymerization catalyst composition comprising a metallocene and an aluminoxane containing alkyl groups with at least two (2) carbon atoms which provides more uniformity than methylaluminoxane, offers greater control and reproducibility of olefin polymerization and greater storage stability. The present invention also provides a method for the preparation of the olefin polymerization catalyst composition.

Abstract: Rotational moulding process for polymerizing or copolmerizing ethylene for manufacturing ethylene polymers or copolymers having a controlled particle size and morphology. Ethylene is polymerized or copolymerized under ethylene polymerizing conditions in the presence of a supported metallocene catalyst, where the average particle size of the catalyst particles is selected within the range of 14-40 &mgr;m and the residence time at the polymerization is selected so as to achieve a polymer where average particle size is between 0.2-0.5 mm and the proportion of fractions between 0.1-0.6 is at least 80%.

Abstract: Olefin polymerization comprising catalysts based on a metallocene, an alumoxane and a support are disclosed. The process for the preparation of a supported olefin ploymerization catalyst comprises: a) a metallocene/activator reaction product, a solvent capable of dissolving it, and a porous support are brought into mutual contact, and b) the solvent is removed, and wherein step a) is carried out so that the porous support is impregnated with a volume of the metallocene/activator reaction product and solvent, which does not exceed the total pore volume of the support.

Abstract: 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.

Abstract: Process for manufacturing ethylene copolymers by polymerizing ethylene and a minor amount of C.sub.3 -C.sub.6 alphaolefins in particle form in slurry reactor in the presence of an ethylene polymerizing catalyst. According to the invention the polymerization is carried out in propane diluent by using a metallocene catalyst activated with an alumoxane compound.

Abstract: 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.

Abstract: 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.

Abstract: The present invention concerns a polymerization catalyst of olefins, said catalyst containing an active chromium compound on an inorganic support. The catalyst in accordance with the invention is prepared by vaporizing a precursor of chromium oxide such as chromyl chloride and allowing the chromium oxide vapor to react with the surface of, e.g., silica gel support material at 160.degree. . . . 500.degree. C. A selective binding of the chromium oxide to the support material is achieved by keeping the vapor pressure sufficiently high and the duration of interaction with the support sufficiently long so as to maintain an excess of the chromium compound in relation to the number of available binding sites on the support material. The activity of a catalyst in accordance with the invention even with a very low content of catalytic metal is as high as the activity of a catalyst of an appreciably higher metal content that has been prepared by the methods of the conventional technology.

Abstract: The invention relates to a new bis(trialkylsilyl) chromate of the formula ##STR1## where n is approximately 1-2. Such a compound can be prepared by causing a corresponding silyl halide to react with silver chromate. The product is especially suitable for the polymerization and copolymerization of ethylene, the formed polymer having a high molar mass and a wide molar mass distribution.

Abstract: The present invention concerns a catalyst for the polymerization of olefins, and a method for preparing the same said catalyst constituting an inorganic support material with catalytically active chromium and titanium compounds bound on its surface. The catalyst is prepared according to the invention by bringing the catalytically active metal compounds sequentially in vapor phase onto the support material surface in excess amounts in relation to the binding sites available on the support material surface. The support material temperature is maintained above the condensation temperature of the vapor, preferably above 160.degree. C., and simultaneously sufficiently high so as to achieve the thermal activation energy necessary for the generation of bonds between the support material and the catalytically active material or its compound. To avoid desorption of the chemisorbed compounds, the temperature is kept below approx. 500.degree. C.