MXPA97003592A

MXPA97003592A - Component of supported catalyst, supported catalyst, its preparation and depolimerization process by adic

Info

Publication number: MXPA97003592A
Application number: MXPA/A/1997/003592A
Authority: MX
Inventors: Spencer Lee; B Jacobsen Grant; L Wauteraerts Peter
Original assignee: The Dow Chemical Company
Priority date: 1994-11-17
Filing date: 1995-11-02
Publication date: 1997-08-01

Abstract

The present invention relates to a supported catalyst component comprising a support material and an alumoxane, wherein the alumoxane is fixed on the support, a supported catalyst comprising said supported catalyst component and transition metal compound, a process for the preparation of the supported catalyst component and the supported catalyst, and a process for the polymerization by addition of addition polymerizable monomers using said catalyst supports

Description

SUPPORTED CATALYST COMPONENT, CATALYST SUPPORTED. YOUR PREPARATION AND PROCESS OF POLYMERIZATION BY ADDITION The present invention relates to a supported catalyst component comprising a support material and alumoxane, to a supported catalyst comprising a support material, alumoxane, and a metallocene compound, to a process for the preparation of this catalyst component. supported and catalyst, and an addition polymerization process using that supported catalyst.

Background of the Invention The homogeneous or unsupported alumoxane-metallocene catalysts are known for their high catalytic activity in olefin polymerizations. Under the polymerization conditions in which the polymer is formed as solid particles, these homogeneous (soluble) catalysts form polymer deposits on the walls of the reactor and in the agitators, whose deposits must be removed frequently, since they impede heat exchange efficient, necessary to cool the contents of the reactor, and cause excessive wear of moving parts. The polymers produced by these soluble catalysts also have a low bulk density, which mimics the commercial utility of both the polymer and the process. In order to solve these problems, several supported alumoxane-metallocene catalysts have been proposed for use in particle forming polymerization processes. The Patent of the United States of North America No. 5,057,475 discloses a supported metallocene-alumoxane catalyst, wherein the alumoxane can be a commercial alumoxane, or an alumoxane generated at the site on the solid support, for example, by the addition of a trialkyl aluminum compound to a support containing water, such as by adding trimethyl aluminum to a silica containing water. In the preferred methods of U.S. Patent No. 5,057,475, the metallocene component and the alumoxane (which may previously have been combined with a modifying compound) are combined in a first step in a suitable solvent, in a subsequent step, this Solution is put in contact with the support. Then the solvent can be removed, typically by applying a vacuum. The solution can be heated in order to assist in the removal of the solvent. In an alternative method, a non-dehydrated silica gel is added to a trialkyl aluminum solution to produce an alumoxane, which is deposited on the surface of the silica gel particles. The solvent is then removed, and the residual solids are dried to a free-flowing powder. In typical examples, the dried silica is formed into a paste with an alumoxane in toluene, filtered, washed with pentane, and then dried under vacuum. The metallocene compound is typically combined with an alumoxane in toluene or heptane, whose solution is subsequently combined with the previously treated silica. Finally, the toluene or heptane is removed in vacuo to recover the supported catalyst. U.S. Patent No. 5,026,797 describes the treatment of a particulate porous support of water-insoluble inorganic oxide with an alumoxane in a solvent for the alumoxane, such as an aromatic hydrocarbon, followed by rinsing the treated support with a aromatic hydrocarbon solvent until alumoxane is no longer detected in the supernatant. Accordingly, it is said that it is possible to adjust the amount of aluminum atoms of the bound alumoxane on the treated oxide support in the range of 2 to 10 weight percent. Subsequently, the treated support is combined with a zirconium compound. The support material thus formed containing alumoxane and the zirconium compound is used together with additional alumoxane in solution in a polymerization reaction. U.S. Patent No. 5,147,949 describes metallocene-alumoxazole-unsupported catalysts prepared by the addition of a catalyst support impregnated with water to a stirred solution of a trialkyl aluminum, and the addition to the reaction product of the same , of a metallocene component. The Patent of the United States of North America No. 5,240,894, discloses a method for producing a supported catalyst by forming a metallocene / alumoxane reaction solution, adding it to a porous carrier, evaporating the resulting paste to remove the residual solvent from the carrier, and optionally the prepolymer -risation of the catalyst with an olefinic monomer. Only a good bulk density of the polymer is obtained using a polymerized pre-supported catalyst. U.S. Patent No. 5,252,529 describes solid catalysts for the polymerization of olefin, which comprise a particulate carrier containing at least 1 weight percent water, an alumoxane compound, and a metallocene compound. In the preparation of this catalyst, the reaction product of the particulate carrier and the alumoxane are separated from the diluent (toluene) by decanting or drying under reduced pressure. European Patent Application Number 368,644 describes a process for the preparation of a supported metallocene-alumoxane catalyst, wherein a non-dehydrated silica gel is added to a stirred solution of triethyl aluminum, to which reaction mixture is added a solution of a metallocene to which trimethylaluminum has been added. Following the addition of the metallocene treated with trimethyl aluminum to the solids of the silica gel treated with triethyl aluminum, the catalyst is dried to a free flowing powder. The drying of the catalyst can be done by filtration or evaporation of the solvent at a temperature of up to 85 ° C. European Patent Application Number 323,716 describes a process for the preparation of a supported metallocene-alumoxane catalyst, by the addition of non-dehydrated silica gel to a stirred solution of a trialkyl aluminum, the addition of a metallocene to the reaction mixture. , the removal of the solvent, and the drying of the solids to obtain a free-flowing powder. After the metallocene has been added, the solvent is removed, and the residual solids are dried at a temperature of up to 85 ° C. European Patent Application Number 523,416 describes a supported catalyst component for the polymerization of olefin prepared from an inorganic support and a metallocene. The metallocene and the support are mixed intensely in a solvent. Preferably, the catalyst component thus obtained is extracted in a suitable solvent, such as toluene, to remove the metallocene, which is not fixed. Subsequently, alumoxane can be added as a cocatalyst. European Patent Application Number 567,952 discloses a supported polymerization catalyst comprising the reaction product of a supported organic aluminum compound and a metallocene catalyst compound. This supported catalyst is prepared by combining trimethyl aluminum with a support material previously dried in an inert aliphatic suspension medium, to which water is added. This suspension can be used as such, or can be filtered, and the solids thus obtained can be resuspended in an inert aliphatic suspension medium, and then combined with the metallocene compound. When the reaction is finished, the solution of the supernatant is removed, and the remaining solid is washed once to five times with an inert suspension medium, such as toluene, normal decan, diesel oil, or dichloromethane. It would be desirable to provide a supported catalyst component, a supported catalyst, and a polymerization process that prevents or substantially reduces the problem of reactor contamination, including the formation of polymer deposits on the walls of the reactor and on the reactor agitator, especially in the processes of polymerization in gas phase or in paste polymerization. Furthermore, it is preferred that the polymer products produced by the gas phase polymerization or paste polymerization processes remain in a free-flowing form, and, conveniently, have high bulk densities.

SUMMARY OF THE INVENTION In one aspect of the present invention, there is provided a supported catalyst component comprising a support material and an alumoxane, which component contains 15 to 40 weight percent aluminum, based on the total weight of the material of support and alumoxane, and where no more than 10 percent of the aluminum present in the supported catalyst component can be extracted in one hour's extraction with toluene at 90 ° C using 10 milliliters of toluene per gram of catalyst component supported, this supported catalyst component can be obtained by: A. heating a support material containing alumoxane under an inert atmosphere for a period and at a temperature sufficient to bind the alumoxane to the support material. In a second aspect, a supported catalyst is provided comprising: the supported catalyst component according to the present invention, and a transition metal compound containing at least one cyclic or non-cyclic n-linked anionic ligand group. According to a further aspect there is provided a process for the preparation of a supported catalyst component, which comprises: A. heating a support material containing alumoxane under an inert atmosphere, for a period and at a temperature sufficient to bind the alumoxane to the support material; in this way select the conditions in the heating step A, to form a supported catalyst component, which component contains 15 to 40 weight percent aluminum, based on the total weight of the support material, and the alumoxane, and wherein no more than 10 percent of the aluminum present in the supported catalyst component can be removed in one hour's extraction with toluene at 90 ° C, using 10 milliliters of toluene per gram of supported catalyst component. In another aspect, the invention provides a process for the preparation of a supported catalyst, which comprises: A. heating a support material containing alumoxane under an inert atmosphere, for a period and at a temperature sufficient to fix the. alumoxane to the support material; and optionally followed by: B. subjecting the support material containing alumoxane, to one or more washing steps, to remove the alumoxane not attached to the support material; in this way, select the conditions in the heating step A, and in the optional washing step B, to form a supported catalyst component, whose component contains 15 to 40 weight percent aluminum, based on the total weight of the support material and alumoxane, and where no more than 10 percent of the aluminum present in the supported catalyst component can be extracted in one hour's extraction with toluene at 90 ° C, using 10 milliliters of toluene per gram of supported catalyst component; and adding, before or after step A or step B, a transition metal compound containing at least one cyclic or non-cyclic n-linked anionic ligand group, with the proviso that, once the Transition metal compound, the product thus obtained is not subjected to temperatures equal to, or higher than, the decomposition temperature of the transition metal compound. In still a further aspect, an addition polymerization process is provided, wherein one or more addition polymerizable monomers are contacted with a catalyst supported in accordance with the present invention, under addition polymerization conditions.

Detailed Description of the Invention All references herein to elements or metals belonging to a certain Group, refer to the Periodic Table of the Elements published and copyrighted by CRC Press, Inc., 1989. Also, any reference to the Group or to the Groups will be to the Group or to the Groups reflected in this Periodic Table of the Elements, using the IUPAC system to number the groups. The term "hydrocarbon" as used herein, means any aliphatic, cycloaliphatic, aromatic group, or any combination thereof. The term "hydrocarbyloxy" means a hydrocarbyl group having an oxygen bond between it and the element to which it is attached. Wherein the term "substituted cyclopenta-dienyl" is used in the specification and in the claims, this includes ring-substituted or polynuclear derivatives of the cyclopentadienyl moiety, wherein this substituent is hydrocarbyl, hydrocarbyloxy, hydrocarbylamino, cyano, halogen, silyl , germyl, siloxy, or mixtures thereof, or two of these substituents with a hydrocarbylene group, this substituent (or two substituents together) having up to 30 non-hydrogen atoms. The term "substituted cyclopentadienyl" specifically includes the indenyl, tetraindenyl, fluorenyl, and octahydrofluorenyl groups. Surprisingly, it has been found that polymers having a good bulk density can be prepared in a particle formation polymerization process, with or without substantially reduced reactor contamination, by using a supported catalyst, wherein the alumoxane is fixed to the support material. In accordance with the present invention, good bulk densities, for ethylene-based polymers and interpolymers, are bulk densities of at least 0.20 grams / cubic centimeter, preferably at least 0.25 grams / cubic centimeter, and more preferably at least 0.30 grams / cubic centimeter. It is believed that the extent of contamination of the reactor is related to the amount of alumoxane that is leached from the support during the polymerization conditions, which can lead to the presence of active catalyst present in the homogeneous phase, and therefore dissolved in the diluent, that under the conditions of particle formation it can give very small polymer particles, or polymer particles of a poor morphology that can adhere to the metal parts or to the static parts of the reactor. In addition, it is believed that the bulk density of a polymer is related to the way in which the alumoxane is fixed to the support, and to the amount of alumoxane not bound on the support, ie, the amount of aluminum that can be extracted. of the support with toluene at 90 ° C. The fixation of the alumoxane on the support in accordance with the specific treatment of the present invention, results in substantially no leaching of alumoxane from the support under the polymerization conditions, and that substantially no soluble active catalyst species are present in the mixture. polymerization. It has been found that the present supported catalysts can be supported not only to prepare polymers and copolymers of ethylene in the traditional high density polyethylene density scale (0.970 to 0.940 grams / cubic centimeter) in the pulp and phase polymerization processes. of gas, but also copolymers with densities of less than 0.940 grams / cubic centimeter and going down to 0.880 grams / cubic centimeter or less, while retaining good bulk density properties, and while substantially reducing or reducing contamination of the reactor. The catalyst component supported in the present invention comprises a support material and an alumoxane, wherein, in general, no more than 10 percent of the aluminum present in the supported catalyst component can be extracted in one hour's extraction with toluene at 90 ° C, using 10 milliliters of toluene per gram of supported catalyst component. Preferably, no more than 9 percent of the aluminum present in the supported catalyst component can be extracted, and more preferably no more than 8 percent can be extracted. It has been discovered that, when the amount of extractables is less than these levels, a good bulk density of the polymer is obtained with the supported catalysts based on these supported catalyst components. The extraction test with toluene is carried out as follows. 1 gram of supported catalyst component or supported catalyst, with a known aluminum content, is added to 10 milliliters of toluene, and then the mixture is heated to 90 ° C under an inert atmosphere. The suspension is stirred well at this temperature for 1 hour. Then, the suspension is filtered by applying reduced pressure to aid in the filtration step. The solids are washed twice with 3 to 5 milliliters of toluene at 90 ° C per gram of solids. The solids are then dried at 120 ° C for 1 hour, and subsequently the aluminum content of the solids is measured. The difference between the initial aluminum content and the aluminum content after extraction, divided by the initial aluminum content, and multiplied by 100 percent, gives the amount of aluminum that can be extracted. The aluminum content is determined by forming a paste of 0.5 grams of supported catalyst component or catalyst supported on 10 milliliters of hexane. The paste is treated with 10 to 15 milliliters of 6N sulfuric acid followed by the addition of a known excess of EDTA. The excessive amount of EDTA is then titrated back with zinc chloride. At a 10 percent level of extractables, the bulk density of the polymer obtained by the polymerization using the supported catalysts (components) described herein, is very sensitive with respect to small changes in the percentage of extractables of aluminum . In view of the sensitivity of the bulk density of the polymer, and the margin of error in determining the percentage of aluminum extractables (estimated to be 1 percent absolute), an alternative test to distinguish the supported catalyst component and the catalyst supported in accordance with the present invention, is to use a catalyst supported in an ethylene polymerization process in a hydrocarbon diluent at 80 ° C and 15 bar, and to determine the degree of contamination of the reactor and / or the Bulk density of the ethylene polymer produced. The substantial absence of contamination of the reactor, that is, if there are substantially no polymer deposits on the walls of the reactor or on the agitator, and / or if the bulk densities are at least 0.20 grams / cubic centimeter, and preferably at least 0.25 grams / cubic centimeter, this is a characteristic of the supported catalyst components and the catalysts of the invention. Suitable support materials for the present invention preferably have a surface area determined by nitrogen porosimetry using the B.E.T. method, from 10 to 1000 square meters / gram, and preferably from 100 to 600 square meters / gram. The porosity of the support is conveniently between 0.5 and 5 cubic centimeters / gram preferably from 0.1 to 3 cubic centimeters / gram, and most preferably 0.2 to 2 cubic centimeters / gram. The average particle size is not critical, but typically is from 1 to 200 microns. Suitable support materials for the supported catalyst component of the present invention include porous resinous materials, for example, styrene-divinylbenzene copolymers, and solid inorganic oxides, such as silica, alumina, magnesium oxide, titanium oxide, thorium, as well as mixed oxides of silica and one or more metal oxides of Group 2 or 13, such as mixed oxides of silica-magnesia and silica-alumina. Silica, alumina, and mixed oxides of silica and one or more metal oxides of Group 2 or 13, are the preferred support materials. Preferred examples of these mixed oxides are the silicas-aluminas. Silica is more preferred. The silica can be in granular form, agglomerated, vaporized, or in another form. Suitable silicas include those available from Grace Davison (division of .R. Grace &; Co.) under the designations SD 3216.30, Devison Syloid 245, Davison 948 and Davison 952, and in Degussa AG, under the designation Aerosil 812. Before use, if desired, the support material can be subjected to a heat treatment and / or a chemical treatment, to reduce the water content or the hydroxyl content of the support material. Typical thermal pretreatments are carried out at a temperature of 30 ° C to 1000 ° C for a duration of 10 minutes to 50 hours in an inert atmosphere or under reduced pressure. The supported catalyst component further comprises an alumoxane component. An alumoxane (also referred to as aluminoxane) is an oligomeric or polymeric oxyaluminium compound containing alternating aluminum and oxygen atom chains, whereby, aluminum carries a substituent, preferably an alkyl group. The exact structure of alumoxane is not known, but in general it is believed that it is represented by the following general formulas: (-Al (R) -0) m, for a. cyclic alumoxane, and R2AI-0 (-Al (R) -0) m-AlR2, for a linear compound, wherein R, independently in each presentation is a hydrocarbyl of 1 to 10 carbon atoms, preferably alkyl, or a halide, and m is an integer from 1 to 50, preferably from at least 4. The alumoxanes are typically the reaction products of water and an alkyl aluminum, in addition to an alkyl group may contain halide or alkoxide groups. The reaction of several different alkyl aluminum compounds, such as, for example, trimethyl aluminum and triisobutyl aluminum, with water, produces the so-called modified or mixed alumoxanes. Preferred alumoxanes are methyl alumoxane and modified methyl alumoxane with minor amounts of other lower alkyl groups, such as isobutyl. The alumoxanes generally contain minor to substantial amounts of the starting alkyl aluminum compound. The manner in which alumoxane is prepared is not critical to the present invention. When prepared by the reaction between water and alkylaluminum, the water can be combined with the alkyl aluminum in different forms, such as liquid, vapor, or solid, for example in the form of water of crystallization. Particular techniques for the preparation of the alumoxane type compounds by contacting an alkyl aluminum compound with an inorganic salt containing water of crystallization are described in U.S. Patent No. 4,542,199. In a particular preferred embodiment, an alkyl aluminum compound is contacted with a substantial one containing regenerable water, such as hydrated alumina, silica, or other substance. This is described in European Patent Application Number 338,044. The supported catalyst component of the present invention generally contains 15 to 40 weight percent, preferably 20 to 40 weight percent, and more preferably 25 to 40 weight percent aluminum, based on the total weight of the support material and the alumoxane. Amounts of aluminum of at least 15 percent by weight, preferably at least 20 percent by weight, and more preferably at least 25 percent by weight, are desirable, because these make it possible to deposit amounts relatively high of transition metal compound on the support, and in this way, make it possible to obtain a relatively high activity. This improves the overall efficiency of the catalyst, especially when expressed on the basis of the support material. The catalyst component supported as such, or formed in a paste in a diluent, can be stored or shipped under inert conditions, or it can be used to generate the supported catalyst of the present invention. According to a further aspect, the present invention provides a supported catalyst comprising the supported catalyst component according to the present invention, and a transition metal compound, preferably a transition metal compound containing at least one group of cyclic or non-cyclic n-linked anionic ligand, preferably a cyclopentadienyl or substituted cyclopentadienyl moiety. Adequate complexes are derivatives of any transition metal, including lanthanides, but preferably of Group 3, 4, 5, or lanthanide metals, which are in the formal oxidation state +2, +3, or + Four. Preferred compounds include metal complexes containing 1 to 3 n-linked anionic ligand groups, which may be cyclic or non-cyclic, non-linked, n-linked anionic ligand groups. Examples of these n-linked anionic ligand groups are dienyl groups, allyl groups, and conjugated or non-cyclic conjugated or non-cyclic arene groups. The term "n-linked" means that the ligand group is linked to the transition metal by means of an n-bond. Each atom in the delocalized n-linked group can be independently substituted by a radical selected from halogen, hydrocarbyl, halohydrocarbyl, and hydrocarbyl substituted metalloid radicals, wherein the metalloid is selected from Group 14 of the Periodic Table of the Elements. Preferred hydrocarbyl radicals include linear, branched, and cyclic alkyl radicals of 1 to 20 carbon atoms, aromatic radicals of 6 to 20 carbon atoms, alkyl substituted aromatic radicals of 7 to 20 carbon atoms. , and alkyl radicals substituted by aryl of 7 to 20 carbon atoms. In addition, two or more of these radicals can together form a fused ring system or a hydrogenated fused ring system. Suitable hydrocarbyl substituted organometalloid radicals include the di- and tri-substituted organometalloid radicals of the Group 14 elements, wherein each of the hydrocarbyl groups contains from 1 to 20 carbon atoms. Examples of suitable hydrocarbyl substituted organometalloid radicals include trimethylsilyl, triethylsilyl, ethyldimethylsilyl, methyldiethylsilyl, triphenylgermyl, and trimethylgermyl groups. Examples of suitable anionic delocalized n-linked groups include cyclopentadienyl, indenyl, fluorenyl, tetrahydroindenyl, tetrafluorenyl, octahydrofluorenyl, pentadienyl, cyclohexadienyl, dihi-droanthracenyl, hexahydroanthracenyl and decahydroanthracenyl groups, as well as the hydrocarbyl substituted derivatives of 1 to 10 atoms. of carbon thereof. The preferred anionic delocalized n-linked groups are cyclopentadienyl, pentamethylcyclopentadienyl, tetramethylcyclopentadienyl, indenyl, 2,3-dimethylindenyl, fluorenyl, 2-methylindenyl, and 2-methyl-4-phenylindenyl. The term "metallocene compound" as used herein, refers to transition metal compounds containing a derivative of a cyclopentadienyl moiety. Suitable metallocenes for use in the present invention are substituted cyclopentadienyl transition metal compounds or bridged or unbridged mono-, bis-, and tri-cyclopenta-dienyl compounds. Suitable non-bridged monocyte-pentadienyl or mono (cyclopentadienyl) transition metal derivatives are represented by the general formula Cp Xn, wherein Cp is cyclopentadienyl or a derivative thereof; M is a transition metal of Group 3, 4, or 5, which has a formal oxidation state of 2, 3, or 4; X independently in each presentation represents an anionic ligand group (different from a cyclic aromatic n-linked anionic ligand group), said X having up to 50 non-hydrogen atoms; and n is a number equal to, or less than, the formal oxidation state of M, and is 1, 2, or 3, preferably 3. Examples of these groups of X ligands are hydrocarbyl, hydrocarbyloxy, hydride, halogen, silyl , germyl, amide and siloxy, or two X groups can together form a hydrocarbylene (including hydrocarbylidene). Suitable bridged monocyclopentadienyl or mono (cyclopentadienyl) transition metal compounds include the well-known limited geometry complexes. Examples of these complexes and methods for their preparation are described in U.S. Patent Application Serial Number 545,403, filed July 3, 1990, (corresponding to European Patent Number EP-A-416). , 815), in U.S. Patent Number 5,374,696 (corresponding to International Patent Number WO-93/19104), as well as in U.S. Patent Nos. 5,055,438; 5,057,475; 5,096,867; 5,064,802 and 5,132,380. More particularly, preferred bridged monocyclopentadienyl or substituted mono (cyclopentadienyl) transition metal compounds correspond to formula I: Cp * M < X > n wherein: M is a metal of Groups 3 to 5, especially a Group 4 metal, particularly titanium; Cp is a substituted cyclopentadienyl group bonded with Z 'and in a bonding mode, with M, or this group is further substituted by from 1 to 4 substituents selected from hydrocarbyl, silyl, germyl, halogen, hydrocarbyloxy, amino, and mixtures thereof, this substituent having up to 20 non-hydrogen atoms, or optionally, two of these additional substituents (with the exception of halogen or ammo) together make Cp to have a fused ring structure; Z 'is a different bivalent moiety of a cyclic or non-cyclic n-linked anionic ligand, said Z1 comprising boron, or a member of Group 14 of the Periodic Table of the Elements, and optionally nitrogen, phosphorus, sulfur, or oxygen, having this fraction up to 20 which are not hydrogen, and optionally Cp and Z 'together form a fused ring system; X, independently in each presentation, is an anionic ligand group (different from a cyclic n-linked group) having up to 50 non-hydrogen atoms; and n is 1 or 2, depending on the valence of M. In keeping with the above explanation, M is preferably a Group 4 metal, especially titanium; n is 1 or 2; and X is a monovalent ligand group of up to 30 non-hydrogen atoms, more preferably hydrocarbyl of 1 to 20 carbon atoms. When n is 1 and the metal of Groups 3 to 5 (preferably Group 4 metal) is in the formal oxidation state +3, X is preferably a stabilizing ligand. The term "stabilizing ligand" means that the ligand group stabilizes the metal complex through: 1) a bond of chelation of nitrogen, phosphorus, oxygen, or sulfur, or 2) a bond r / 3 with a structure n- decentralized electronic resonant. Examples of the stabilizing ligands of Group 1 include the silyl, hydrocarbyl, amido, or phosphide ligands, substituted by one or more functional groups of ether, thioether, amine, or phosphine, aliphatic or aromatic, especially the amine or phosphine groups which are tertiaryly substituted, this stabilizing ligand having from 3 to 30 non-hydrogen atoms. The most preferred Group 1 stabilizing ligands are 2-dialkylamino-benzyl or 2- (dialkylaminomethyl) phenyl groups containing from 1 to 4 carbon atoms in the alkyl groups. Examples of the stabilizing ligands of group 2 include hydrocarbyl groups of 3 to 10 carbon atoms containing ethylenic unsaturation, such as the allyl, 1-methylallyl, 2-methylallyl, 1,1-dimethylallyl, or 1,2-groups, 3-trimethylallyl. Still more preferably, the metal coordination complexes correspond to formula II: wherein R 'in each presentation, is independently selected from hydrogen, hydrocarbyl, silyl, germyl, cyano, halogen, and combinations thereof, having up to 20 non-hydrogen atoms, or two R' groups (with the exception of cyano or halogen) together form a divalent derivative thereof. X, in each presentation, is independently selected from hydride, halogen, alkyl, aryl, silyl, germyl, aryloxy, alkoxy, amide, siloxy, and combinations thereof having up to 20 non-hydrogen atoms; Y is a divalent anionic ligand group comprising nitrogen, phosphorus, oxygen, or sulfur, and having up to 20 non-hydrogen atoms, said Y bonding with Z and through nitrogen, phosphorus, oxygen, or sulfur, and optionally Y and Z together form a fused ring system, - M is a Group 4 metal, especially titanium; Z is SiR * 2, CR * 2, SiR * 2SiR * 2, CR * 2CR *, CR * = CR *, CR 2SiR 2, GeR 2, BR, OR BR 2; wherein: R in each presentation, is independently selected from the groups hydrogen, hydrocarbyl, silyl, halogenated alkyl, halogenated aryl having up to 20 non-hydrogen atoms, and mixtures thereof, or two or more R groups from Z, or a group R from Z together with Y form a fused ring system, - and n is 1 or 2. In addition, more preferably, Y is -O-, -S-, -NR -, -PR -. In a highly preferable manner, Y is a group containing nitrogen or phosphorus corresponding to the formula -N (R ') - or -P (R') -, where R 'is as described above, ie a group amido or phosphide. The most highly preferred metal coordination complexes correspond to formula III: wherein: M is titanium; Rr, in each presentation, is independently selected from hydrogen, silyl, hydrocarbyl, and combinations thereof having up to 20, preferably up to 10 carbon or silicon atoms, or two R 'groups of the substituted cyclopentadienyl moiety they unite with each other; E is silicon or carbon; X, independently in each presentation, is hydride, halogen, alkyl, aryl, aryloxy, or alkoxy of up to 10 carbon atoms, - m is 1 or 2; and n is 1 or 2. Examples of the most highly preferred metal coordination compounds above include compounds wherein R 'on the amido group is methyl, ethyl, propyl, butyl, pentyl, hexyl (including its isomers), norbornyl, benzyl , phenyl, or cyclododecyl, - (ER'2) m is dimethylsilane or 1,2-ethylene, -R1 on the cyclic n-linked group, independently in each presentation, is hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, norbornyl, benzyl, or phenyl, or two R 'groups are joined to form a fraction of indenyl, tetraindenyl, fluorenyl, or octahydrofluorenyl, - and X is chlorine, bromine, iodine, methyl, ethyl, propyl, butyl, pentyl, hexyl , norbornyl, benzyl, or phenyl. Specific highly preferred compounds include: (tertiary butyl amido) (tetramethyl-r * -cyclopenta-dienyl) -1,2-ethanedyltitanium-dimethyl, (tertiary butyl amido) (tetramethyl-r * -cyclopentadienyl) -1, 2 -etandiiltitanium-dibenzyl, (tertiary butyl-amido) (tetramethyl-r? -cyclopenta-dienyl) -dimethylsilanetitanium-dimethyl, (tertiary butyl-amido) (tetramethyl- * 75-cyclopentadienyl) dimethylsilanetitanium-dibenzyl, (methylamido) (tetramethyl) 17-cyclopentadienyl) dimethylaminosteotitanium-dimethyl, (methylamido) (tetramethyl-7 * -5-cyclopen-thienyl) dimethylsilanetitanium-dibenzyl, (phenylamido) (tetramethyl-17-cyclopentadienyl) dimethyl silanetitanium dimethyl, (phenylamido) ( tetramethyl-17-cyclopentadienyl) dimethylsilanetite-nio-dibenzyl, (benzylamido) (tetramethyl-17-cyclopentadienyl) dimethylsilanetitanium-dimethyl, (benzylamido) (tetramethyl-tj-cyclopentadienyl) dimethylsilanetitanium-dibenzyl, (tertiary butyl amido) (rj-cyclopentadienyl) ) -1, 2-ethanedyltitanium-dimethyl, (butyl tertiary rio-amido) (17-cyclopentadienyl) -1,2-ethanedyltitanium-dibenzyl, (tertiary butyl amido) (? -cyclopentadienyl) dimethylsilanetitanium-dimethyl, (tertiary butyl-amido) (17-cyclopentadienyl) dimethylsilanetitanium-dibenzyl, (methylamido) (17-cyclopentadienyl) dimethylsilanethi-tanium-dimethyl, (tertiary-butyl amido) (17-cyclopentadie-nyl) dimethylsilanetitanium -dibenzyl, (tertiary butyl-amido) (indenyldimethylsilanetitanium-dimethyl, (tertiary butyl-amido) indenyldimethylsilanetitanium-dibenzyl, (benzylamido) in-denyldimethylsilanetitanium-dibenzyl, * and the corresponding zirconium or hafnium coordination complexes. transition wherein the transition metal is in the formal +2 oxidation state, and the processes for its preparation are described in detail in International Patent Number WO 9500526, which corresponds to the United States Patent Application with Serial Number 241,523, filed on May 12, 1994. Suitable complexes include those that contain one, and only one n-link group anionic, delocalized, cyclical, these complexes corresponding to formula IV: / \ IV L M- x * wherein: M is titanium or zirconium in the formal oxidation state +2; L is a group that contains a cyclic, delocalized, anionic system, through which the group is linked to M, and whose group also links to Z; Z is a moiety linked to M by means of a bond s, which comprises boron, or a member of group 14 of the Periodic Table of the Elements, and which also comprises nitrogen, phosphorus, sulfur, or oxygen, this fraction having up to 60 non-hydrogen atoms, - and X is a neutral, conjugated or non-conjugated diene, optionally substituted by one or more hydrocarbyl groups, said X having up to 40 carbon atoms, and forming a n complex with M.

Preferred transition metal compounds of formula IV include those wherein Z,, and X are as defined above; and L is a C5H4 group linked to Z, and linked in a linkage mode? with M, or is a group linked with? 5 substituted by one to four substituents independently selected from hydrocarbyl, silyl, germyl, halogen, cyano, and combinations thereof, this substituent having up to 20 non-hydrogen atoms , and optionally, two of these substituents (with the exception of cyano or halogen) together make L to have a fused ring structure. The more preferred transition metal compounds +2 according to the present invention correspond to formula V: wherein: R 'in each presentation, is independently selected from hydrogen, hydrocarbyl, silyl, germyl, halogen, cyano, and combinations thereof, said R' having up to 20 non-hydrogen atoms, and optionally, two R 'groups (wherein R' is not hydrogen, halogen, or cyano) together form a divalent derivative thereof connected with the adjacent positions of the cyclopentadienyl ring to form a fused ring structure; X is a diene group linked to? neutral that has up to 30 non-hydrogen atoms, which forms a n complex with M; And it is -O-, -S-, -NR * -, -PR * -; M is titanium or zirconium in the formal oxidation state +2; and Z * is SiR * 2, CR * 2, SiR * 2SiR * 2, CR * 2CR * 2, CR * = CR *, CR 2SiR 2, or GeR 2; wherein: R, in each presentation, is independently hydrogen, or a member selected from hydrocarbyl, silyl, halogenated alkyl, halogenated aryl, and combinations thereof, said R having up to 10 non-hydrogen atoms, and optionally two group R from Z (wherein R is not hydrogen), or a group R from Z and a group R from Y, form a ring system. Preferably, R 'independently in each presentation, is hydrogen, hydrocarbyl, silyl, halogen, and combinations thereof, said R' having up to 10 non-hydrogen atoms, or two R 'groups (when R' is not hydrogen) or halogen) together form a bivalent derivative thereof; more preferably, R 'is hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl (including where all isomers are appropriate), cyclopentyl, cyclohexyl, norbornyl, benzyl, or phenyl, or two R' groups (with the exception of of hydrogen) are bonded together, the entire group C5R * 4 being in this manner, for example, an indenyl, tetrahydroindenyl, fluorenyl, tetrahydrofluorenyl, or octahydrofluorenyl group. More preferably, at least one of R 'or R is an electron donor moiety. The term "electron donor" means that the fraction is more electron donor than hydrogen. Accordingly, in a highly preferable manner, Y is a nitrogen or phosphorus containing group corresponding to the formula -N (R ") - or -P (R") -, where R "is hydrocarbyl of 1 to 10 atoms Examples of suitable X groups include: s-trans-? -1,4-diphenyl-1,3-butadiene; s-trans-tj -3-methyl-l, 3-pentadiene; j * -1, 4-dibenzyl-l, 3-butadiene, -s-trans-ij * -2, 4-hexadiene, -s-trans-ij -1, 3-pentadiene, -s-trans-17 -1 , 4-ditolyl-1,3-butadiene; s-trans-17 -1,4-bis (trimethylsilyl) -1,3-butadiene, - s-cis-t * -1,4-diphenyl-1, 3- butadiene; s-cis-17 -3-methyl-1,3-pentadiene, - s-cis-t-l, 4-dibenzyl-1,3-butadiene; s- 'cis-r * -2,4- hexadiene, - s-cis-77 -1, 3-pentadiene, - s-cis-17 -1,4-ditolyl-1,3-butadiene, and s-cis-rj -1, 4-bis (trimethylsilyl) - 1, 3-butadiene, the s-cis-diene group forming a complex n as defined herein with the metal. The most highly preferred transition metal compounds +2 are the amidosilane or amidoalkandiyl compounds of the formula V, wherein: -Z * -Y- is - (ER "'JJJ-NÍR") -, and R in each The present invention is independently selected from hydrogen, silyl, hydrocarbyl, and combinations thereof, said R 'having up to 10 carbon or silicon atoms, or two of these R' groups on the substituted cyclopentadienyl group (wherein R 'not is hydrogen) together form a bivalent derivative thereof, connected to the adjacent positions of the cyclopentadienyl ring; R "is hydrocarbyl of 1 to 10 carbon atoms; R" ', independently in each presentation, is hydrogen or hydrocarbyl of 1 to 10 carbon atoms, - E, independently in each presentation, is silicon or carbon; and m is 1 or 2. Examples of the metal compounds according to the present invention include compounds wherein R "is methyl, ethyl, propyl, butyl, pentyl, hexyl (including all isomers of the foregoing where applicable) , cyclododecyl, norbornyl, benzyl, or phenyl; (ER "'2) m is dimethylsilane, or ethanediyl, - and the n-linked cycloalkyl group is cyclopentadienyl, tetramethylcyclopentadienyl, indenyl, tetrahydroindenyl, fluorenyl, tetrahydrofluorenyl or octahydrofluorenyl. Suitable substituted bis-cyclopentadienyl or cyclopentadienyl transition metal compounds include those containing a bridging group linking the cyclopentadienyl groups, and those without bridging groups. Suitable non-bridged bis-cyclo-pentadienyl or substituted bis (cyclopentadienyl) transition metal derivatives are represented by the general formula Cp2MXn > wherein Cp is an n-linked cyclopentadienyl group, or a n-linked substituted cyclopentadienyl group, and M and X are as defined with respect to formula II, and n 'is 1 or 2, and is two less than the state of formal oxidation of M. Preferably n 'is 2. Examples of non-bridged bis-cyclopentadienyl transition metal derivatives are: cis-cyclopentadienylzirconium-dimethyl, bis-cyclopentadie-nylzirconium-dibenzyl, bis (methylcyclopentadienyl) zirconium-dimethyl , bis (butyl-cyclopentadienyl) zirconium-dimethyl-bis (tertiary butyl-cyclopentadienyl) zirconium-dimethyl, bis (pentamethylcyclopentadienyl) zirconium-dimethyl, bis (indenyl) zirconium-dibenzyl, bis (fluorenyl) zirconium-dimethyl , bis (pentamethylcyclopentadienyl) zirconium bis [2- (N, N-dimethylamino) benzyl], and the corresponding titanium and hafnium derivatives.

Preferred bridge groups are those corresponding to the formula (ER "2) X, wherein E is silicon or carbon, R", independently in each presentation, is hydrogen or a group selected from silyl, hydrocarbyl, and combinations thereof, said R "having up to 30 carbon or silicon atoms, and x is from 1 to 8. Preferably, R", independently in each presentation, is methyl, benzyl, tertiary butyl, or phenyl.

The bridged ligands sample containing two-linked n group are: (dimethylsilyl-bis-cyclopentadienyl), (dimethylsilyl-bis-methylcyclopentadienyl), (dimethylsilyl-bis-ethylcyclopentadienyl), (dimethylsilyl-bis-tertiarybutyl-cyclopentadienyl), ( dimethylsilyl-bis-tetrametilciclopentadie-nile), (dimethylsilyl-bis-indenyl), (dimethylsilyl-bis-tetrahi-droindenilo), (dimethylsilyl-bis-fluorenyl), (dimethylsilyl-bis-tetrahydrofluorenyl), (dimethylsilyl-bis-2- methyl-4-phenylindenyl), (dimethylsilyl-bis-2-methylindenyl), (dimethylsilyl-cyclopentadienyl fluorenyl), (1,1,2, 2-tetramethyl-l, 2-disilyl-bis-cyclopentadienyl), ( . 1, 2-bis (cyclopentadienyl) eta-not, and (isopropylidene-cyclopentadienyl-fluorenyl) examples of bis-cyclopentadienyl complexes or bis (substituted cyclopentadienyl) above bridged are compounds corresponding to formula VI: where: M, X, E, R ', and n are as defined for the complexes of formula III. Two of the substituents X can together form a neutral n-linked conjugated diene having from 4 to 30 non-hydrogen atoms, forming a n-complex with M, on which, M, which is preferably zirconium or hafnium, is in the formal oxidation state +2. The above metal complexes are especially suitable for the preparation of polymers having a stereoregular molecular structure. In this capacity, it is preferred that the complex possess a Cs symmetry, or possess a stereorigid chiral structure. Examples of the first type are compounds possessing different delocalized p-linked systems, such as a cyclopentadienyl group and a fluorenyl group. Similar systems based on Ti (IV) or Zr (IV) were described for the preparation of syndiotactic olefin polymers in Ewen et al. J. Am. Chem. Soc., Volume 110, pages 6255-6256 (1980). Examples of chiral structures include bis-indenyl complexes. Similar systems based on Ti (IV) or Zr (IV) were described for the preparation of isotactic olefin polymers in Wild et al J. Orcranomet. Chem. Volume 232, pages 233-47, (1982). The example complexes of formula IV are: (dimethylsilyl-bis-cyclopentadienyl) zirconium-dimethyl, (dimethylsilyl-bis-tetramethylcyclopentadienyl) zirconium-dimethyl, (dimethylsilyl-bis-butyl-butyl-cyclopentadienyl) zirconium-diphenyl, (dimethylsilyl-bis-tetramethylcyclopentadienyl) zirco-nio-dibenzyl, ( dimethylsilyl-bis-indenyl) zirconium-bis (2-dimethylaminobenzyl), (isopropylidene-cyclopentadienyl-fluore-nil) zirconium dimethyl, [2, 2 'biphenyldiylbis (3, 4-dimethyl-l-cyclopentadienyl)] titanium dibenzyl, [6,6-dimethyl-2, 2'-biphenyl-bis (3,4-dimethyl-1-cyclopentadienyl)] zirconium-dimethyl, and the corresponding titanium and hafnium complexes. Suitable substituted tricyclo-pentadienyl or cyclopentadienyl transition metal compounds include those containing a bridging group that binds two cyclopentadienyl groups, and those without those bridging groups.

Suitable unbridged tricyclopentoadienyl transition metal derivatives are represented by the general formula Cp3MXn «, where Cp, M, and X are as defined above, and n" is three less than the formal oxidation state of M, y is 0 or 1, preferably 1. the ligand groups X preferred are hydrocarbyl, hydrocarbyloxy, hydride, halo, silyl, germyl, amido, and siloxy. preferably the compiiesto transition metal is a compound of transition metal of Group 4 mono-clopentadienyl bridged, or a bridged bis-cyclopentadienyl Group 4 transition metal compound, more preferably a bridged monocyclopentadienyl transition metal compound, especially a compound wherein the metal is titanium. Other compounds that are useful in the preparation of catalyst compositions in accordance with this invention, especially compounds containing other Group 4 metals, will, of course, be apparent to those skilled in the art. In general, the molar ratio of the aluminum atom (from the alumoxane component) to the transition metal atom in the supported catalyst is from 1 to 5000, preferably from 25 to 1000, and more preferably from 50 to 500. In Too low ratios, the supported catalyst will not be very active, while at too high rates, the catalyst becomes less economical because of the relatively high cost associated with the use of large amounts of alumoxane. The amount of transition metal compound in the supported catalyst of the present invention is not critical, but is typically from 0.1 to 1000 micromoles of transition metal compound per gram of support material. Preferably, the supported catalyst contains from 1 to 250 micromoles of transition metal compound per gram of support material. It has been found that higher loads of aluminum on the support result in catalysts having higher efficiencies, when expressed on a transition metal base, compared with catalysts having lower aluminum fillers but approximately the same proportion of the same. aluminum to transition metal. These higher aluminum load bearing components also provide supported catalysts that have higher efficiencies when expressed based on aluminum or support material. The supported catalyst of the present invention can be used as such, or in a pre-polymerized form obtained by subjecting an olefin, in the presence of the supported catalyst, to polymerization conditions. The supported catalyst component of the invention can be obtained by heating a support material containing alumoxane, under an inert atmosphere, for a period and at a temperature sufficient to bind the alumoxane to the support material. The alumoxane containing support material can be obtained by combining, in a diluent, an alumoxane with a support material containing from 0 to no more than 20 weight percent water, preferably from 0 to no more than 6 percent by weight of water, based on the total weight of the support material and water. Support materials that substantially do not contain water give good results with respect to the catalytic properties of the supported catalyst. In addition, it has been found that support materials containing relatively small amounts of water can be used without problem in the present process. The water-containing support materials, when combined under identical conditions with the same amount of alumoxane, give, in the present process, a supported catalyst component having an aluminum content slightly higher than the substantially water-free support material. It is believed that the water reacts with the residual amounts of aluminum alkyl present in the alumoxane, to convert the aluminum alkyl to extra alumoxane. An additional advantage is that, in this way, less alkylaluminum will be lost to the waste or recycle streams. The alumoxane is desirably used in a dissolved form. Alternatively, the alumoxane containing support material can be obtained by combining, in a diluent, a support material containing 5 to 30 weight percent water, preferably 6 to 20 weight percent. water weight, based on the total weight of the support material and water, with a compound of the formula R "n * AlX" 3.n * where R ", independently in each presentation, is a hydrocarbyl radical, X" is halogen or hydrocarbyloxy, and n * is an integer from 1 to 3. Preferably, n * is 3. When the alumoxane is prepared at the site by reacting the compound of the formula R "n * AlX" 3_n * with water, the molar ratio of R "n * AlX" 3_n * to water is typically from 10: 1 to 1: 1, preferably from 5: 1 to 1: 1. The support material is added to the alumoxane or to the compound of the formula R "n * AlXM3_n *, preferably dissolved in a solvent, more preferably a hydrocarbon solvent or the solution of alumoxane or the compound of the formula R" n * AlX "3.r? *" Is added to the support material The support material can be used as such in dry form or in a paste in a hydrocarbon diluent Both aliphatic and aromatic hydrocarbons can be used Suitable aliphatic hydrocarbons include, for example, pentane, isopentane, hexane, heptane, octane, isooctane, nonane, isononane, decane, cyclohexane, methylcyclohexane, and combinations of two or more of these diluents.The suitable examples of aromatic diluents are benzene, toluene, xylene, and others. aromatic compounds substituted by alkyl or halogen More preferably, the diluent is an aromatic hydrocarbon, especially toluene.The suitable concentrations of solid support in the hydr Ocarbide are from 0.1 to 15, preferably from 0.5 to 10, more preferably from 1 to 7 weight percent. Contact time and temperature are not critical. Preferably, the temperature is from 0 ° C to 60 ° C, more preferably from 10 ° C to 40 ° C. The contact time is 15 minutes to 40 hours, preferably from 1 hour to 20 hours. Before subjecting the alumoxane containing support material to the heating step, the diluent or solvent is removed to obtain a free flowing powder. This is preferably done by applying a technique that only removes the liquid and leaves the aluminum compounds on the solid, such as by the application of heat, reduced pressure, evaporation, or combinations of these techniques. The heating step A followed by the optional washing step B is conducted in such a way that a very large proportion (more than 90 weight percent) of the alumoxane remaining on the supported catalyst component is fixed. In the heating step, the alumoxane is fixed to the support material, while, in the optional washing step, the alumoxane which is not; fixed is removed to a substantial degree to provide the supported catalyst component of the present invention. The upper temperature for the heat treatment is preferably lower than the temperature at which the support material begins to agglomerate and form lumps that are difficult to re-disperse, and lower than the decomposition temperature of the alumoxane. When the metallocene compound is added before the heat treatment, as will be explained herein, the heating temperature must be lower than the decomposition temperature of the metallocene compound. The alumoxane containing support material in free flowing or powder form, is preferably subjected to a heat treatment at a temperature of at least 75 ° C, preferably at less than 85 ° C, more preferably at least 100 ° C C, up to 250 ° C, more preferably up to 200 ° C, for a period of 15 minutes to 72 hours, preferably up to 24 hours. More preferably, the heat treatment is carried out at a temperature of 160 ° C to 200 ° C for a period of 30 minutes to 4 hours. Good results have been obtained while heating for 8 hours at 100 ° C, as well as while heating for 2 hours at 175 ° C. By means of preliminary experiments, a person skilled in the art will be able to define the heat treatment conditions that provide the desired result. It is noted that the longer the heat treatment, the higher the amount of alumoxane fixed to the support material. The heat treatment is carried out at a reduced pressure or under an inert atmosphere, as nitrogen gas, but preferably at a reduced pressure. Depending on the conditions in the heating step, the alumoxane can be fixed to the support material to a high degree that the washing step can be omitted. In the optional washing step B, the number of washes and the solvent used are that quantities of unbound, bound alumoxane are removed sufficient to give the supported catalyst component of the invention. The washing conditions must be that the unfixed alumoxane is soluble in the wash solvent. The alumoxane containing support material, already subjected to a heat treatment, is preferably subjected to one to five washing steps using an aromatic hydrocarbon solvent, at a temperature of 0 ° C to 110 ° C. More preferably, the temperature is from 20 ° C to 100 ° C. Preferred examples of aromatic solvents include toluene, benzene, and xylenes. More preferably, the aromatic hydrocarbon solvent is toluene. At the end of the washing treatment, the solvent is removed by a technique that also removes the alumoxane dissolved in the solvent, as by filtration or decantation. Preferably, the wash solvent is removed to provide a free flowing powder of the supported catalyst component. The washing step can conveniently be carried out under reflux conditions of the washing solvent. The washing step under reflux conditions allows to control the particle size distribution properties, preferably to give a distribution similar to that of the starting support material, and it has also been found that it gives a supported catalyst having a higher polymerization activity. Typically, the supported catalyst component, after the heating step, is formed into a paste in an aromatic hydrocarbon, and the slurry is refluxed or heated to the boiling point of the aromatic hydrocarbon. The paste is maintained under these reflux conditions for 5 minutes up to 72 hours. Any agglomerated particles that may have formed during the heating step will deagglomerate or disperse during the wash step in the reflux condition. The longer the reflux conditions are maintained, the better the dispersion obtained. The concentration of the catalyst component supported in the aromatic hydrocarbon is not critical, but typically is in the range of 1 to 500 grams per liter of hydrocarbon, preferably 10 to 250 grams per liter. Preferred examples of aromatic hydrocarbons include toluene, benzene, and xylenes. More preferably, the aromatic hydrocarbon solvent is toluene. During the reflux step, agitation can be applied. The supported catalyst component of the present invention, after the wash or reflux steps described above, is preferably subjected to a dispersion treatment before combining the supported catalyst component with the transition metal compound. It has been found that this increases the catalytic activity of the final supported catalyst. In general, a hydrocarbon is used as a dispersion medium, such as aliphatic, cycloaliphatic, or aromatic hydrocarbons. Suitable examples are aliphatic hydrocarbons having from 6 to 20 carbon atoms, preferably from 6 to 10 carbon atoms, or mixtures thereof. The temperature is not critical, but conveniently it is on the scale of 0 ° C to 50 ° C. The duration is in general from at least 5 minutes to 72 hours. The upper limit is not critical, but is determined by practical considerations. The transition metal compound is preferably added after the heating step, and more preferably after both the heating step and the optional washing and dispersing steps. If the transition metal compound is added before any of these steps, care must be taken not to subject the transition metal to too high temperatures that can cause its decomposition or inactivation. Conveniently, the transition metal compound is added after the washing step, in order to prevent the transition metal from being stripped from the support material together with the alumoxane. The transition metal is contacted with the alumoxane containing support material and preferably with the supported catalyst component of the present invention, in a diluent, preferably under conditions such that the transition metal compound is soluble. Suitable diluents include aliphatic and aromatic hydrocarbons, preferably an aliphatic hydrocarbon such as, for example, hexane. The metallocene is preferably added to a paste of the support material, conveniently dissolved in the same diluent in which the paste of the support material was made. In general, the alumoxane containing support material is formed in a paste in the diluent in concentrations of 1 to 20, preferably 2 to 10 percent by weight. Contact time and temperature are not critical. Preferably, the temperature is from 10 ° C to 60 ° C, more preferably from 20 ° C to 45 ° C. The contact time is from 5 minutes to 100 hours, preferably from 0.5 hours to 3 hours. Typically, the diluent is removed after adding the metallocene. This can be done by any suitable technique, such as the application of heat and / or reduced pressure, evaporation, filtration, or decanting, or any combination thereof. If heat is applied, the temperature should not exceed the decomposition temperature of the metallocene. It may be convenient to subject an olefin, in the presence of the supported catalyst, to polymerization conditions, to provide a supported polymerized catalyst. In a highly preferred embodiment, the process for the preparation of a supported catalyst comprises: Heating, at a temperature of 75 ° C to 250 ° C, under an inert atmosphere, preferably under reduced pressure, a silica support material containing methylalumoxane; optionally followed by subjecting the product of the heating step to one or more washing steps using toluene; selecting in this way the conditions in the heating step and in the wash step, to form a supported catalyst component, wherein no more than 9 percent of the aluminum present in the supported catalyst component can be extracted in an extraction hour with toluene at 90 ° C, using one gram of catalyst component supported by 10 milliliters of toluene; and adding, after the heating step and the optional washing step, a transition metal compound selected from a bridged monocyclopentadienyl or substituted mono (cyclopentadienyl) transition metal compound 4, or a metal compound of transition of Group 4 of bis-cyclopentadienyl or bridged bis (substituted cyclopentadienyl), with the proviso that once the transition metal compound has been added, the product thus obtained is not subjected to temperatures equal to, or higher than, that, its decomposition temperature. Preferably, the supported catalyst thus prepared contains from 20 to 40 weight percent aluminum, based on the total weight of the support material and alumoxane. Conveniently, the molar ratio of the aluminum atom to the transition metal atom in the supported catalyst thus formed is from 25 to 1000. Preferably, the supported catalyst thus formed contains from 0.1 to 1000 micromoles of the metal compound of transition per gram of support material. The supported catalyst thus obtained can be used as such, without isolation or purification, but preferably it is first recovered in the form of free-flowing particles. The isolated catalyst can be stored under an inert atmosphere for a long period of time, for example, for one to several months. Before use, the supported catalyst can easily be re-formed into a paste in a diluent, preferably a hydrocarbon. The present supported catalyst does not require additional activators or cocatalysts. In a further aspect, the present invention provides an addition polymerization process, wherein one or more addition polymerizable monomers are contacted with the supported catalyst according to the invention, under addition polymerization conditions. Suitable addition polymerizable monomers include ethylenically unsaturated monomers, acetylenic compounds, conjugated or non-conjugated dienes, polyenes, and carbon monoxide. Preferred monomers include defines, for example, alpha-olefins having from 2 to 20, preferably from 2 to 12, more preferably from 2 to 8 carbon atoms, and combinations of two or more of these alpha-olefins. Particularly suitable alpha-olefins include, for example, ethylene, propylene, 1-butene, 1-pentene, 4-methylpentene-1, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene. , 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, or combinations thereof. Preferably the alpha olefins are ethylene, propene, 1-butene, 4-methylpentene-1, 1-hexene, 1-octene, and combinations of ethylene and / or propene with one or more of these other alpha-olefins. Other preferred monomers include styrene, styrenes substituted by halogen or by alkyl, vinyl chloride, acrylonitrile, methyl acrylate, methyl methacrylate, tetrafluoroethylene, methacrylonitrile, vinylidene chloride, vinylcyclobutene, 1,4-hexadiene, and 1,7-octadiene. . Suitable addition polymerizable monomers also include any mixtures of the aforementioned monomers. The supported catalyst can be formed at the site, in the polymerization mixture, by introducing into said mixture, either a supported catalyst component of the present invention, or a suitable metallocene component. The supported catalyst component and the supported catalyst of the present invention, they can be conveniently employed in a high pressure, solution, paste, or gas phase polymerization process. A high-pressure process is normally carried out at temperatures of 100 ° C to 400 ° C, and at pressures greater than 500 bar. A pulp process typically utilizes an inert hydrocarbon diluent and temperatures of 0 ° C to a temperature just below the temperature at which the resulting polymer becomes substantially soluble in the inert polymerization medium. Preferred temperatures are from 20 ° C to 115 ° C, preferably from 60 ° C to 105 ° C. The solution process is carried out at temperatures from the temperature at which the resulting polymer is soluble in an inert solvent up to 275 ° C. In general, the solubility of the polymer depends on its density. For ethylene copolymers having densities of 0.86 grams / cubic centimeter, solution polymerization can be achieved at temperatures as low as 60 ° C. Preferably, the solution polymerization temperatures are from 75 ° C to 260 ° C, more preferably from 80 ° C to 170 ° C. As the inert solvents, hydrocarbons are typically used, and preferably aliphatic hydrocarbons. The processes in solution and in paste are normally carried out at pressures between 1 and 100 bar. Typical operating conditions for gas phase polymerizations are from 20 ° C to 100 ° C, more preferably from 40 ° C to 80 ° C. In gas phase processes, the pressure is typically from subatmospheric to 100 bar. Typical gas phase polymerization processes are described in U.S. Patents Nos. 4,588,790; 4,543,399; 5,352,749; 5,405,922, and in the United States Patent Application Serial Number 122,582, filed September 17, 1993 (corresponding to International Patent Number WO 9507942). Preferably, for use in the gas phase polymerization processes, the support has an average particle diameter of 20 to 200 microns, more preferably 30 microns to 150 microns, and most preferably 35 microns to 100 microns. Preferably, for use in the pulp polymerization processes, the support has an average particle diameter of 1 to 200 microns, more preferably 5 microns to 100 microns, and most preferably 20 microns to 80 microns. Preferably, for use in the solution or high pressure polymerization processes, the support has an average particle diameter of 1 to 40 microns, more preferably 2 microns to 30 microns, and most preferably 3 microns to 20 microns. The supported catalysts of the present invention, when used in a pulp process or in a gas phase process, can not only produce ethylene copolymers of typical densities for high density polyethylene, in the range of 0.970 to 0.940 grams. / cubic centimeter, but, in a surprising way, also make possible the production of copolymers having substantially lower densities. Copolymers of densities of less than 0.940 grams / cubic centimeter and especially less than 0.930 grams / cubic centimeter and down to 0.880 grams / cubic centimeter or less can be made, while retaining good properties of bulk density, and while prevents or substantially eliminates contamination of the reactor. The present invention can produce polymers and copolymers of ethylene with weight average molecular weights of up to 1,000,000 and still higher. In the polymerization process of the present invention, impurity scavengers can be used, which serve to protect the supported catalyst from catalyst poisons, such as water, oxygen, and polar compounds. These scavengers can generally be used in amounts dependent on the amounts of impurities, and are typically added to the feed of monomers and diluents, or to the reactor. Typical scavengers include alkylaluminum or boron compounds and alumoxanes. In the present polymerization process, also, molecular weight control agents, such as hydrogen or other chain transfer agents can be used. Having described the invention, the following examples are provided as another illustration thereof, and should not be construed as limiting. Unless otherwise reported, all parts and percentages are expressed on a weight basis.

E-jemples In the examples, the following support materials were used: granular silica available in Grace GmbH under the designation SD 3216.30; a spherical agglomerated silica available as SYLOPOL 2212 by Grace Davison (division of W.R. Grace &Co.) which has a surface area of 250 square meters / gram, and a pore volume of 1.4 cubic centimeters / gram. Unless otherwise indicated, the silicas used have been heated at 250 ° C for 3 hours under vacuum, to give a final water content of substantially 0, determined by differential scanning calorimetry. Where silica containing water was used, it was used as supplied, without prior heat treatment. Alumoxane was used as a 10 percent by weight solution of methyl alumoxane (MAO) in toluene, available from Witco GmbH. Metallocene was used as a 0.0714 M solution of. { (tertiary butyl amido) (tetramethyl-t * 5-cyclopentadienyl) (dimethyl) silane} titanium-dimethyl (subsequently in the present MCpTi) in ISOPARMR E (registered trademark of Exxon Chemical Company). • The bulk density of the polymers produced was determined in accordance with ASTM 1895. The aluminum content on the support material was determined by its treatment with sulfuric acid, followed by addition of EDTA, and titration back with zinc chloride. All experiments were conducted under a nitrogen atmosphere, unless otherwise indicated.

Example 1 A 1000 milliliter flask was charged with 11.1 grams of silica SD 3216.30. 300 grams of a solution of methyl alumoxane were added, and the mixture was stirred for 16 hours. Then the solvent was removed under reduced pressure at 20 ° C, to give 38 grams of a free-flowing powder, with an aluminum content of 31.6 percent. The sample was divided into four equal portions of 9 grams, and each was heated at a different temperature for 2 hours under reduced pressure. After this treatment, the aluminum content of each sample was measured, and then each was formed into a paste in toluene (100 milliliters), and the mixture was stirred for 1 hour, filtered, and then the supports were washed with two 50 milliliter portions of fresh toluene, and dried under vacuum at 120 ° C for 1 hour. The results of the aluminum analyzes are summarized below.

Table I - Heat Treatment / Washing with Toluene at Room Temperature The above procedure was repeated, but with 12.1 grams of silica, and 327 grams of alumoxane methyl solution to give 42 grams of a free-flowing powder having an aluminum content of 31.3 percent. This sample was divided into four equal portions, and each was heated as described above, and then subjected to the same washing procedure, except that toluene was used at 90 ° C. The results are summarized in Table II.

Table II - Heat Treatment / Washing with Toluene at 90 ° C These examples show that, for heat treatments of the duration, an increase in the temperature of the heat treatment results in more alumoxane being fixed in the silica. Washing with toluene at 90 ° C results in a higher percentage of unfixed aluminum being removed, compared to washing with toluene at room temperature for the same duration washing treatments.

Example 2 A 250 milliliter flask was charged with 6.2 grams of silica SD 3216.30. 168 grams of alumoxane methyl solution was added, and the mixture was stirred for 16 hours. After this time, the toluene was removed under reduced pressure at 20 ° C, and then the solids were dried under vacuum for 16 hours at 20 ° C to give a free-flowing powder. The weight of the solid was 22.1 grams, and the aluminum content was 26.8 percent.

Example 3 The procedure of Example 2 was repeated, using 3 grams of silica and 56.6 grams of alumoxane methyl solution, to give 7.6 grams of a free flowing powder, with an aluminum content of 26.1 percent. 5.2 grams of this support were formed in a paste in toluene (50 milliliters) at 20 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 20 milliliter portions of fresh toluene, and then dried under vacuum at 20 ° C for 1 hour. The weight was 3.0 grams, and the aluminum content was 18.2 percent.

Example 4 The procedure of Example 2 was repeated, using 3 grams of silica and 75.6 grams of alumoxane methyl solution, to give a free flowing powder. Then this powder was heated at 100 ° C for 2 hours under vacuum. The weight was 8.4 grams, and the aluminum content was 29.0 percent. 4.4 grams of this support was formed in a paste in toluene (50 milliliters) at 20 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 20 milliliter portions of fresh toluene, and then dried under vacuum at 20 ° C for 1 hour. The weight was 2.2 grams, and the aluminum content was 17.3 percent.

Example 5 The procedure of Example 2 was repeated, using 3 grams of silica and 56.6 grams of alumoxane methyl solution, to give a free flowing powder. The powder was heated for 2 hours at 150 ° C under vacuum. The weight obtained was 7.2 grams, and the aluminum content was 26.6 percent.

Example 6 The procedure of Example 2 was repeated, using a 1000 milliliter flask, 12.1 grams of silica, and 327 grams of alumoxane methyl solution, to give a free flowing powder. Then 9.5 grams of this powder was heated at 175 ° C for 2 hours under vacuum. The aluminum content was measured as 30.7 percent. 2.7 grams of support was formed in a paste in hexane (40 milliliters) at 20 ° C, and the mixture was stirred for 4 hours. The mixture was filtered, and the support was washed with two 30-milliliter portions of fresh hexane, and then dried under vacuum at 20 ° C for 1 hour. The weight was 2.4 grams, and the aluminum content was 30.4 percent.

Example 7 The procedure of Example 2 was followed. This powder was then heated at 150 ° C for 2 hours under vacuum. The weight was 7.25 grams, and the aluminum content was 26.6 percent. 3 grams of the obtained support were formed in a paste in toluene (40 milliliters) at 20 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 10-milliliter portions of fresh toluene, and then dried under vacuum at 20 ° C for 1 hour. The weight was 2.4 grams, and the aluminum content was 24.1 percent.

Example 8 The procedure of Example 2 was repeated, using 3 grams of silica and 75.5 grams of methyl alumoxane solution, to give a free-flowing powder. This powder was heated at 150 ° C for 2 hours under vacuum. The weight was 8.4 grams, and the aluminum content was 29.8 percent. grams of this support were formed in a paste in toluene (40 milliliters) at 20 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 20 milliliter portions of fresh toluene, and then dried in vacuo at 20 ° C for 1 hour. The weight was 4.5 grams, and the aluminum content was 28.9 percent.

Example 9 The procedure of Example 2 was repeated, using a 1000 milliliter flask, 9.1 grams of silica, and 246 grams of methyl alumoxane solution, to give a free-flowing powder. Then this powder was heated at 150 ° C for 2 hours under vacuum. The weight was 29.0 grams, and the aluminum content was 29.6 percent. This support was formed into a paste in toluene (300 milliliters) at 20 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 100-milliliter portions of fresh toluene, and then dried under vacuum at 20 ° C for 1 hour. The weight was 24. 3 grams and the aluminum content was 28.5 percent.

B? A-mplr »10 The procedure of Example 2 was repeated, using 5 grams of silica and 101 grams of methyl alumoxane solution, to give a free-flowing powder. The powder was heated at 175 ° C for 2 hours under vacuum. The aluminum content of this material was 28.8 percent. The powder (12.8 grams) was re-formed into a paste in toluene (130 milliliters) and the mixture was heated to 90 ° C, and stirred for 1 hour. The mixture was filtered, and the resulting solid was washed with two 50 milliliter portions of fresh toluene at 90 ° C. The support was then dried under vacuum at 120 ° C for 1 hour. 10.4 grams of support having an aluminum content of 26.3 percent was obtained.

Example 11 The procedure of Example 2 was repeated, using 10 grams of silica and 76 grams of methyl alumoxane solution, to give a free flowing powder. This powder was heated at 175 ° C for 2 hours under vacuum. The aluminum content of this material was 17.2 percent. The dust (15.6 grams) was re-formed into a paste in toluene (150 milliliters), and the mixture was heated to 90 ° C, and stirred for 1 hour. The mixture was filtered and the resulting solid was washed with two 50 milliliter portions of fresh toluene at 90 ° C. The support was then dried under vacuum at 120 ° C for 1 hour. Obtained 13.0 grams of support with an aluminum content of 16.3 percent.

Example 12 The procedure of Example 2 was repeated, using 5 grams of silica SD 3216.30 with a water content of 2.8 percent, and 101 grams of alumoxane methylene solution, to give a free-flowing powder. This powder was heated at 175 ° C for 2 hours under vacuum. The aluminum content of this material was 29.4 percent. The powder (13 grams) was re-formed into a paste in toluene (130 milliliters), and the mixture was heated to 90 ° C, and stirred for 1 hour. The mixture was filtered, and the resulting solid was washed with two 50 milliliter portions of fresh toluene at 90 ° C. The support was then dried under vacuum at 120 ° C for 1 hour. 11.5 grams of support with an aluminum content of 29.0 percent were obtained.

Example 13 The procedure of Example 2 was repeated, using a 1000 milliliter flask, 9 grams of SYLOPOL 2212 and 243 grams of alumoxane methyl solution, to give a free flowing powder. This powder was heated at 150 ° C for 2 hours under vacuum. The weight was 29.3 grams, and the aluminum content was 29.8 percent. This support was formed into a paste in toluene (300 milliliters) at 20 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 100 milliliter portions of fresh toluene, and then dried under vacuum at 120 ° C for 1 hour. The weight was 25.9 grams, and the aluminum content was 29.3 percent.

Example 14 The procedure of Example 2 was repeated, using a 1000-milliliter flask, 9.1 grams of silica, and 246 grams of methyl alumoxane solution, to give a free-flowing powder. This powder was heated at 175 ° C for 2 hours under vacuum. The weight of 30.8 grams, and the aluminum content was 30.0 percent. This support was formed in a paste in toluene (300 milliliters) at 20 ° C and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 100 milliliter portions of fresh toluene, and then dried under vacuum at 120 ° C for 1 hour. The weight was 27.1 grams, and the aluminum content was 29.0 percent.

Example 15 The procedure of Example 2 was repeated, using 5. l grams of silica and 101 grams of alumoxane methyl solution, to give a free flowing powder. 6.8 grams of this powder were heated at 100 ° C for 2 hours under vacuum. The support was then formed into a paste in toluene (100 milliliters) at 90 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 50 milliliter portions of fresh toluene (90 ° C), and then dried under vacuum at 100 ° C for 1 hour. The weight was 3.4 grams, and the aluminum content was 16.6 percent.

Example 16 The procedure of Example 2 was repeated, using 5.1 grams of silica and 101 grams of methyl alumoxane solution, to give a free flowing powder. 6.8 grams of this powder were formed into a paste in toluene (100 milliliters) at 90 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 50 milliliter portions of fresh toluene (90 ° C), and then dried under vacuum at 100 ° C for 1 hour. The weight was 3.0 grams, and the aluminum content was 13.4 percent.

Example 17 The procedure of Example 2 was repeated, using 5 grams of silica SD 3216.30 containing 2.8 percent water, and 101 grams of methyl alumoxane solution, to give a free-flowing powder. 6 grams of this powder were formed into a paste in toluene (100 milliliters) at 90 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 50 milliliter portions of fresh toluene (90 ° C), and then dried under vacuum at 20 ° C for 1 hour. The weight was 2.9 grams, and the aluminum content was 16.4 percent.

Example 18 The procedure of Example 2 was repeated, using 5 grams of silica SD 3216.30, containing 2.8 percent water, and 101 grams of alumoxane methyl solution, to give a free-flowing powder. This powder was heated at 100 ° C for 2 hours. 6 grams of this powder were formed into a paste in toluene (100 milliliters) at 90 ° C, and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 50 milliliter portions of fresh toluene (90 ° C), and then dried under vacuum at 20 ° C for 1 hour. The weight was 3.8 grams, and the aluminum content was 22.2 percent.

Example 19 Preparation of supported catalysts Supported catalysts were separated from the supported catalyst components prepared in Examples 2 to 18, according to the following procedure. Typically, 1 gram of support component was formed into a paste in 20 milliliters of hexane, and the mixture was stirred for 30 minutes. An aliquot of MCpTi solution (0.0714 M) sufficient to give a transition metal filler was added as shown in Table III. This mixture was stirred for 30 minutes, and then transferred to a polymerization reactor.

Polymerization A 10 liter autoclave reactor was charged with 6 liters of anhydrous hexane, comonomer if required, hydrogen gas if required, and the contents heated to 80 ° C, unless otherwise reported. Ethylene was added to raise the pressure to the desired level. The amount of the supported catalyst indicated in Table III was added through a pressurized addition cylinder. Ethylene was supplied to the reactor continuously on demand. After the desired polymerization time, the ethylene line was blocked, and the contents of the reactor were vented to a sample receptor. The hexane was decanted from the polymer, and the polymer was dried overnight, and then weighed to determine the yield. In run 22, the temperature was 70 ° C, and 100 milliliters of 1-octene comonomer was added to the reactor, to give an ethylene / 1-octene copolymer of a density of 0.9266 grams / cubic centimeter. In test 23, the temperature was 50 ° C, and 200 milliliters of l-octene comonomer was added to the reactor, to give an ethylene / 1-octene copolymer of a density of 0.9230 grams / cubic centimeter. The specific polymerization conditions and results are summarized in Table III. The data in this table shows that polymers of high bulk density can be prepared from supported catalyst components prepared with different combinations of heat and / or wash treatments. The highest efficiencies result from the supported catalyst components and the catalysts containing more than 20 percent Al by weight. Higher efficiencies of the supported catalyst components subject to dispersion in toluene at 90 ° C are obtained. Poor bulk densities (test 1 to 3) of the supported catalyst components result which have not been heat treated at a sufficiently high temperature, or for a sufficiently long time, or have not been sufficiently washed.

Table III - Polymerization Tests Aluminum content of supported catalyst component Titanium content of supported catalyst in micromoles / gram of support (silica + Alumoxane Methyl) 3. Molar ratio of aluminum and titanium in the supported catalyst 4. Micromoles of titanium added to the reactor in the form of supported catalyst 5. Total polymerization pressure 6. Polymerization time 7. Grams of polymer produced 8. Efficiency of the catalyst expressed by grams of Ti in the supported catalyst 9. Efficiency of the catalyst expressed by grams of silica in the supported catalyst 10. Efficiency of the catalyst expressed by grams of Al in the supported catalyst Table III - (continued) - Polymerization Tests 1. Aluminum content of supported catalyst component 2. Titanium content of supported catalyst in micromoles / gram of support (silica Alumoxane Methyl) 3. Molar ratio of aluminum and titanium in the supported catalyst 4. Micromoles of titanium added to the reactor in the form of supported catalyst 5. Total polymerization pressure 6. Polymerization time 7. Grams of polymer produced 8. Efficiency of the catalyst expressed by grams of Ti in the supported catalyst 9. Efficiency of the catalyst expressed by grams of silica in the supported catalyst 10. Efficiency of the catalyst expressed by grams of Al in the supported catalyst Example 20 The procedure of Example 2 was repeated, using 6.2 grams of silica SD 3216.30, and 68 grams of alumoxane methyl solution, to give 22.1 grams of free-flowing powder, with an aluminum content of 27.8 percent. 11 grams of this support were formed in a paste in toluene (75 milliliters), and 440 micromoles of MCpTi (6.16 milliliters of a 0.07142Vf solution in hexane) were added. The mixture was stirred for 1 hour, and then the solvent was removed under reduced pressure, and the residue was heated at 150 ° C for 2 hours. This produced 11 grams of a free-flowing powder with an aluminum content of 28.2 percent. The material was formed into a paste in toluene (100 milliliters), and the mixture was stirred for 1 hour, filtered, and the solids were washed with two 50 milliliter portions of fresh toluene, and then dried under vacuum at 100 °. C for 1 hour. The weight was 9 grams, the aluminum content was 24.8 percent, and the Ti content was 40 micromoles / gram.

Example 21 The procedure of Example 6 was repeated, using 12.1 grams of silica SD 3216.30, and 327 grams of alumoxane methyl solution, to give a free flowing powder. 9.1 grams of this powder were heated at 150 ° C under vacuum for 2 hours, to give a material with an aluminum content of 30.7 percent. 3.5 grams of this powder were formed into a paste in toluene (35 milliliters), and 140 micromoles of MCpTi (1.96 milliliters of a 0.0714W solution in hexane) were added and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with 6 portions of 50 milliliters of fresh toluene (at which point, the washes were colorless), and then dried under vacuum at 20 ° C for 1 hour. The weight was 22.0 grams, the Ti content was 30 micromoles / gram.

Example 22 The procedure of Example 2 was repeated, using 3.0 grams of silica SD 3216.30, and 82 grams of alumoxane methyl solution, to give 10.5 grams of a free flowing powder. 4.85 grams of this powder were formed into a paste in toluene (50 milliliters), and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 20 milliliter portions of fresh toluene, and then heated under vacuum at 150 ° C for 2 hours. The weight was 2.1 grams, and the aluminum content was 14.9 percent. MCpTi was added according to the procedure of Example 19.

Example 23 A 250 milliliter flask was charged with 3.3 grams of silica SD 3216.30. Toluene (80 milliliters) was added to the paste, followed by 130 micromoles of MCpTi (1.82 milliliters of a 0.07142VT solution) in hexane), and the mixture was stirred for 2 hours. 101 grams of alumoxane methyl solution was added, and the mixture was stirred for 16 hours. After this time, the solvent was removed under reduced pressure, at 20 ° C, to give a free-flowing powder. Following the general polymerization procedure of Example 19, using the specific conditions mentioned in Table IV, the results indicated in the same Table were obtained. The data in this table shows that a low activity catalyst results when metallocene is added before a heat treatment at 150 ° C (Example 20). A reasonable bulk density is obtained when the metallocene is added after the passage of heat, but before the washing step (Example 21). A good bulk density results when the washing step is carried out before the heating step (Example 22). An inactive catalyst results when the metallocene is first added to the silica (Example 23).

Table IV - Polymerization Tests The footings are the same as for Table III Example 24 The procedure of Example 1 was repeated, except that after removing the solvent from the mixture of alumoxane methyl / silica under reduced pressure at 20 ° C, parts of the resulting powder were subjected to heat treatments of 2 hours, and to treatments of optional washing, as summarized in Table V. After these treatments, the supported catalyst components on the one hand, were extracted with toluene at 90 ° C to establish the percentage of extractables of aluminum, and on the other hand, were used in the polymerization reactions. All washing and extraction steps were carried out with 1 gram of support per 10 milliliters of toluene, stirred for 1 hour, then filtered and washed with twice 5 milliliters of toluene per gram of initial support. The supported catalysts were prepared according to the general procedure described in Example 19. All polymerizations were carried out at a total pressure of 15 bar at 80 ° C for 1 hour. The results are given in Table VI. The examples show that in percentages of extractable aluminum well below 10 percent, excellent bulk densities are obtained. Heat treatment at 175 ° C only in Test 1, without washing treatment, made it possible to make polymers of a good density in bulk.

Table V Extraction Test Table VI - Polymerization Tests The footings are the same as for Table III Example 25 The procedure of Example 2 was repeated, using 5 grams of silica and 101 grams of methyl alumoxane solution, to give a free flowing powder. The powder was heated at 100 ° C for 8 hours under vacuum, to give 12.5 grams of the material. The support was then formed into a paste in toluene (125 milliliters) at 90 ° C and the mixture was stirred for 1 hour. The mixture was filtered, and the support was washed with two 50 milliliter portions of fresh toluene (90 ° C), and then dried under vacuum at 100 ° C for 1 hour. The weight was 11.1 grams and the aluminum content was measured as 26.1 weight percent. In accordance with the procedures of Example 19 and using the amounts in Table VII, a polymerization experiment was performed at a total pressure of 15 bar, 80 ° C for 1 hour. The results are included in Table VII. Table VII - Polymerization Test The footnotes are the same as in Table III.

The procedure of Example 5 of US Pat. No. 5,240,894 was repeated essentially to form a supported catalyst component as follows. 0.58 micromoles of MCpTi (8.1 milliliters of a 0.0714 solution) were added to 35 milliliters of toluene. To this was added 75 milliliters of 10 weight percent alumoxane methyl, in toluene, and the mixture was stirred for 15 minutes. Silica (5 grams, SD 3216.30, previously treated at 250 ° C for 3 hours) was added, and the mixture was stirred for 20 minutes. The mixture was heated at 65 ° C under vacuum for 75 minutes, and the dried solid was washed with 2 x 70 milliliters of pentane, filtered, and dried under high vacuum, to give a yellow solid (8 grams), with a content of aluminum of 18.1 percent by weight. Extraction with toluene at 90 ° C, followed by drying gave a yellow solid with an aluminum content of 16.2 weight percent. The percentage of extractable aluminum is 10.5 percent. When washing, some MCpTi was lost, and also on extraction with hot toluene, as indicated by the yellow color of the supernatant. Polymerization experiments were performed following the general procedure of Example 19, with a supported catalyst that was not treated with hot toluene (Test 1), and with one that was treated with hot toluene (Test 2). The results are given in Table VIII.

The results show that the catalyst not treated with toluene (which has 10.5 percent Al removable) gives a poor bulk density. Subjection of the obtained supported catalyst to an extraction with hot toluene greatly improves the bulk density (Test 2).

Table VIII Example 27 A 1000 milliliter flask was charged with 508 grams of 10 percent methyl alumoxane solution in toluene, and 25 grams of silica SYLOPOL 2212, with a water content of 3.5 percent, was added while stirring continuously. The mixture was stirred for another two hours and then the solvent was removed under reduced pressure at 20 ° C, to give a free-flowing powder. Then this powder was heated at 175 ° C for 2 hours under vacuum. The powder was re-formed into a paste in toluene (700 milliliters), and the mixture was heated and refluxed for 1 hour. The mixture was filtered, and the support was washed with two 200 milliliter portions of fresh toluene at 100 ° C. Then the support was dried under vacuum at 120 ° C for 1 hour. 63.9 grams of support were obtained, with an aluminum content of 26.4 percent. A sample of the support was formed into a paste in toluene, stirred for 1 hour, and then the particle size distribution was measured on a Malvern mastersizer X instrument. This indicated that d (v, 0.5) was about 12 microns. In accordance with this procedure, other supported catalyst components were prepared with slightly different aluminum fillers. A weighted amount of the support components was formed in a paste in hexane, and the mixture was stirred for 16 hours before the addition of the MCpTi component (tests 1 to 3) or. { (tertiary butyl amido) (tetramethyl-? -cyclopentadienyl) (dimethyl) silane} titanium-17-l, 3-pentadiene (subsequently in the present MCpTi (II) in test 4). Subsequently, MCpTi or MCpTi (II) (in ISOPARMR E) was added in the amounts indicated in Table IX. The supported catalysts thus prepared were subjected to paste polymerization, as generally described in Example 19, at 80 ° C. The other conditions and results are mentioned in Table IX. These results show that, employing a long dispersion period before the transition metal compound is added, a greater catalytic activity results (compare with Table III).

Table IX Example 28 A 3 liter autoclave reactor was charged with an amount of 1-octene as indicated in Table X, followed by an amount of Isopar® E sufficient to give a total volume of 1500 milliliters. 300 milliliters of hydrogen gas was added, and the contents of the reactor were heated to the desired temperature. Then ethylene was added, enough to bring the system pressure up to 30 bar. A supported catalyst was added to initiate the polymerization, and ethylene was supplied to the reactor continuously on demand. After the desired polymerization time, the ethylene line was blocked, and the contents of the reactor were vented to a sample vessel. The polymer was dried overnight, and then weighed to determine catalyst efficiencies. The results are described in Table X, where the molecular weight distribution (Mw / Mn) is derived from gel permeation chromatography, and the I2 melt index is determined in accordance with ASRM D-1238-65T (at 190 ° C and with a load of 2.16 kilograms). The following supported catalysts were used in the polymerizations. A support containing 23.8 percent aluminum on dehydrated SD 3216.30 silica was prepared, in a manner similar to Example 10. In tests 1 to 3, 0.075 grams of support was formed into a paste in Isopajr * 1, and stirred for a few minutes.

An aliquot of MCpTi solution (0.0714) was added, sufficient to give a titanium loading of 20 micromoles / gram. This mixture was stirred for a few minutes, and then transferred to the polymerization reactor. In tests 4 to 6, 0.3 grams of support was used, and the same load of titanium.

Table X When used in a solution polymerization process, the supported catalysts show good efficiencies, and make polymers of narrow molecular weight distribution.

Example 29 In the present example, continuous polymerization tests are described. These tests were performed utilizing a supported catalyst prepared according to a procedure similar to that of Example 27. The support contained 25 weight percent aluminum. In all the tests, the MCpTi load was 40 micromoles / gram. Isopentane, ethylene, 1-butene, hydrogen, and supported catalyst were continually fed to a continuously agitated 10 liter jacketed tank reactor, and the formed pulp product was continuously stirred. The total pressure in all the polymerization tests was 15 bar. The removed paste was fed into an evaporation tank, to remove the diluent, and the free flowing dry polymer powder was collected. Table XI summarizes the conditions and properties of the products made. The values of the melt index were measured according to ASTM D-1238-65T (at 190 ° C, and with a load of 21.6 kilograms, abbreviated as I21) • The butene content of the polymer was determined by infrared spectroscopy. The results indicate that polymer powders of a high bulk density can be produced over a wide range of density, retaining the morphology of the particles.

Table XI

Claims

1. A supported catalyst component comprising a support material and an alumoxane, which component contains 15 to 40 weight percent aluminum, based on the total weight of the support material and the alumoxane, and wherein it can not be extracting more than 10 percent of the aluminum present in the supported catalyst component in a 1 hour extraction with toluene at 90 ° C, using 10 milliliters of toluene per gram of supported catalyst component, this supported catalyst component being obtainable by: A. Heating a support material containing alumoxane in a free-flowing powder form, under an inert atmosphere, for a period and at a temperature sufficient to bind the alumoxane to the support material.

2. The supported catalyst component of claim 1, wherein the heating step A is followed by: B. subjecting the support material containing alumoxane, to one or more washing steps, to remove the alumoxane not bound to the material of support.

The supported catalyst component of claim 2, wherein the washing step is carried out under reflux conditions of the washing solvent, forming a paste with the catalyst component supported on an aromatic hydrocarbon, and heating the pulp to the point of boiling the aromatic hydrocarbon.

4. The supported catalyst component according to any of claims 1 to 3, wherein no more than 9 percent of the aluminum present in the supported catalyst component can be removed.

The supported catalyst component according to any of claims 1 to 4, wherein the support material is silica.

6. The supported catalyst component according to any of claims 1 to 5, wherein the alumoxane is methyl alumoxane.

The supported catalyst component according to any of claims 1 to 6, which contains from 20 to 40 weight percent of aluminum, based on the total weight of the support material and the alumoxane.

8. A supported catalyst, which comprises: a supported catalyst component according to any of claims 1 to 7; and a transition metal compound.

The supported catalyst of claim 8, wherein the transition metal compound is a bridged monocyclopentadienyl Group 4 transition metal compound, or a bridged bis-cyclopentadienyl Group 4 transition metal compound.

The supported catalyst according to claim 8 or 9, wherein the molar ratio of the aluminum atom to the transition metal atom is from 1 to 5000.

The supported catalyst according to any of claims 8 to 10 , which contains 0.1 to 1000 micromoles of transition metal compound per gram of support material.

The supported catalyst according to any of claims 8 to 11, in a prepolymerized form, obtained by subjecting an olefin, in the presence of the supported catalyst, to polymerization conditions.

13. A process for the preparation of a supported catalyst component, which comprises: A. heating a support material containing alumoxane in free flowing powder form under an inert atmosphere, for a period and at a temperature sufficient to fix the alumoxane to the support material; selecting in this manner the conditions, in the heating step A, to form a supported catalyst component, which component contains 15 to 40 weight percent aluminum, based on the total weight of the support material and the alumoxane, and wherein no more than 10 percent of the aluminum present in the supported catalyst component can be removed in one hour's extraction with toluene at 90 ° C, using 10 milliliters of toluene per gram of supported catalyst component.

14. The process of claim 13, wherein the heating step A is followed by: B. subjecting the support material containing alumoxane, to one or more washing steps, to remove the alumoxane not bound to the support material.

The process of claim 14, wherein the washing step is carried out under reflux conditions of the washing solvent, forming a paste with the catalyst component supported on an aromatic hydrocarbon, and heating the pulp to the boiling point of the aromatic hydrocarbon.

16. The process according to any of claims 13 to 15, wherein the heat treatment is carried out at a temperature of 75 ° C to 250 ° C.

17. The process according to any of claims 14 to 16, wherein the wash solvent is an aromatic hydrocarbon solvent.

18. The process according to claim 17, wherein the aromatic hydrocarbon solvent is toluene.

19. The process according to any of claims 13 to 18, wherein the heat treatment is carried out under reduced pressure.

20. The process according to any of claims 13 to 19, wherein the support material is silica.

21. The process according to any of claims 13 to 20, wherein the alumoxane is methyl alumoxane.

22. A process for the preparation of a supported catalyst, which comprises: preparing a supported catalyst component according to any of claims 13 to 21; and adding, before or after the heating step A or optional washing step B, a transition metal compound, with the proviso that once the transition metal compound has been added, the product thus obtained is not subject to temperatures equal to, or higher than, the decomposition temperature of the transition metal compound.

The process of claim 22, wherein the transition metal compound is added after the heating step.

The process according to claim 23, wherein the transition metal compound is added after the optional washing step.

25. The process according to any of claims 22 to 24, wherein the transition metal compound is a bridged mono-cyclopentadienyl or substituted mono (cyclopentadienyl) transition metal compound, or a metal compound transition group of bis- (cyclopentadienyl) or bis (substituted cyclopentadienyl) bridged.

26. The process according to any of claims 22 to 25, wherein the molar ratio of the aluminum atom to the transition metal atom in the supported catalyst is from 1 to 5000.

27. The process according to any of claims 22 to 26, wherein the supported catalyst contains from 0.1 to 1000 micromoles of transition metal compound per gram of support material.

The process according to any of claims 22 to 27, which further comprises subjecting an olefin, in the presence of a supported catalyst, to polymerization conditions, to provide a previously supported polymerized catalyst.

29. An addition polymerization process, wherein one or more addition polymerizable monomers are contacted with a supported catalyst according to any of claims 8 to 12, or can be obtained according to any of claims 22 to 28 under addition polymerization conditions.

30. The process of addition polymerization according to claim 29, carried out under paste or gas phase polymerization conditions.