Patent Description:
The benefits of the polyethylenes produced using metallocene catalyst are well known in the state of the art and have been commercialized for film producers since <NUM> in the world. Currently, there is a quantity of well-established families of polyethylene produced with metallocenes and new polymers are constantly being introduced onto the market. Each family is made using a different combination of catalyst/reactor and each of these produces a single set of polymer properties.

The mPEBDL (Linear Low Density Polyethylene obtained with metallocenes) polymers can be typically produced in gas phase reactors, among others, and their properties enable them to be used in special films, industrial sacks and flexible packaging for foods. Two specific examples of application for mPEBDL are plastic stretch packaging for frozen food and plastic shrink wrap for wrapping primary packages such as bottles or cans, widely used in Brazil. [CEH Linear Low Density Polyethylene LLDPE Resins <NUM> - SRI Consulting].

To use metallocenes at industrial plants for polymerization of ethylene that operate with gas phase processes, these catalysts must be heterogeneized by immobilization thereof on solid supports. Among the different supports already described in the state of the art, silica is by far the one used most.

The routes for immobilization of metallocenes on the surface of the silica described in the state of the art can be divided, mostly, into three large groups: (i) direct immobilization (See, for example, <NPL>; <NPL>;<NPL>); (b) immobilization on silica modified with metylaluminoxane or with other cocatalysts; (See, for example, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>) and (c) immobilization on silica modified with organoborans (See, for example, <CIT>, <CIT>, <CIT>, <CIT>). The state of the art also relates to the topic of metallocene supported on a polyhedral oligomeric silsesquioxane-modified silica (see for example: "<NPL>) and "<NPL>).

Generally, the supported metallocene catalysts for use in a gas phase process result in copolymers of ethylene and α-olefins with inferior properties to those noted for copolymers obtained by using homogenous complexes, such as, for example, those of the constrained geometry catalyst (CGC) type, in processes in solution. Therefore, it is considered a technological challenge, in light of the state of the art, to develop a supported metallocene catalyst, for a gas phase process, that produces mPEBDL with uniform distribution of comonomer in the polymer chains.

Patent <CIT> teaches the preparation of supported metallocene catalysts by a non-hydrolytic sol-gel process. In the preparation protocol used, a hybrid silica is synthesized by condensing an organosilane containing anionic ligands, a halogenated silane and an alkoxysilane. The hybrid silica generated is subsequently subjected to a metallation reaction and the resulting catalyst is active, in the presence of a cocatalyst, in the polymerization of olefins. However, the proposed route does not enable the formation of a hybrid soluble silica in hydrocarbons and, consequently, the morphological control of the supported catalyst. Moreover, the polymers obtained do not display a uniform distribution of the incorporated comonomer.

As can be observed in the art, it is neither described nor expected that the immobilization of a metallocene on a support modified with a hybrid silica endowed with aliphatic groups will result in a catalyst that combines the following characteristics: high catalytic activity, suitable morphology for industrial process and capacity to produce copolymers with homogenous distribution of comonomer.

The present invention provides a metallocene catalyst based on a transition metal of groups <NUM> or <NUM> of the periodic table immobilized on a support modified with hybrid soluble silica, comprising.

There is also described a process of obtaining a supported metallocene catalyst comprising the following steps:.

Lastly, the present invention also pertains to the use of the supported metallocene catalyst used in process of copolymerization of ethylene with alpha-olefins, resulting in polymers with uniform distribution of incorporated comonomer and with high molar mass value in the ultra-high molar mass fraction (Mz).

The supported metallocene catalyst of the present invention has advantages over the state of the art such as high catalytic activity, morphology, besides the fact of producing copolymers of ethylene with alpha-olefins having molecular behavior that will bring benefits in mechanical properties, such as resistance to tearing, piercing and impact, as well as improved optical and weldability properties.

The present invention will next be described in greater detail based on examples of execution represented in the drawings. The drawings show:.

For an improved understanding, below are certain abbreviations and explanations on the terms mentioned in the present specification:.

The present invention pertains to a metallocene catalyst based on a transition metal of groups <NUM> or <NUM> of the periodic table supported on a support modified with hybrid soluble silica, prepared by a non-hydrolytic sol-gel process.

The supported metallocene catalyst on a support modified with hybrid soluble silica of the present invention comprises:.

Representative but non-limitative examples of compounds having formula <NUM> include: Cp<NUM>TiCl<NUM>, Cp<NUM>ZrCl<NUM>, Cp<NUM>HfCl<NUM>, Cp<NUM>VCl<NUM>, Cp<NUM>Ti(Me)<NUM>, Cp<NUM>Zr(Me)<NUM>, Cp<NUM>Hf(Me)<NUM>, Cp<NUM>Ti(OMe)<NUM>, Cp<NUM>Zr(OMe)<NUM>, Cp<NUM>Hf(OMe)<NUM>, Cp<NUM>Ti(OEt)<NUM>, Cp<NUM>Zr(OEt)<NUM>, Cp<NUM>Hf(OEt)<NUM>, Ind<NUM>TiCl<NUM>, Ind<NUM>ZrCl<NUM>, Ind<NUM>HfCl<NUM>, Ind<NUM>VCl<NUM>, Ind<NUM>Ti(Me)<NUM>, Ind<NUM>Zr(Me)<NUM>, Ind<NUM>Hf(Me)<NUM>, Ind<NUM>Ti(Me)<NUM>, Ind<NUM>Zr(OMe)<NUM>, Ind<NUM>Hf(OMe)<NUM>, Ind<NUM>Ti(OEt)<NUM>, Ind<NUM>Zr(OEt)<NUM>, Ind<NUM>Hf(OEt)<NUM>, Flu<NUM>TiCl<NUM>, Flu<NUM>ZrCl<NUM>, Flu<NUM>HfCl<NUM>, Flu<NUM>VCl<NUM>, Flu<NUM>Ti(Me)<NUM>, Flu<NUM>Zr(Me)<NUM>, Flu<NUM>Hf(Me)<NUM>, Flu<NUM>Ti(OMe)<NUM>, Flu<NUM>Zr(OMe)<NUM>, Flu<NUM>Hf(OMe)<NUM>, Flu<NUM>Ti(OEt)<NUM>, Flu<NUM>Zr(OEt)<NUM>, Flu<NUM>Hf(OEt)<NUM>, (MeCp)<NUM>TiCl<NUM>, (MeCp)<NUM>ZrCl<NUM>, (MeCp)<NUM>HfCl<NUM>, (MeCp)<NUM>VCl<NUM>, (MeCp)<NUM>Ti(Me)<NUM>, (MeCp)<NUM>Zr(Me)<NUM>, (MeCp)<NUM>Hf(Me)<NUM>, (MeCp)<NUM>Ti(OMe)<NUM>, (MeCp)<NUM>Zr(OMe)<NUM>, (MeCp)<NUM>Hf(OMe)<NUM>, (MeCp)<NUM>Ti(OEt)<NUM>, (MeCp)<NUM>Zr(OEt)<NUM>, (MeCp)<NUM>Hf(OEt)<NUM>, (nBuCp)<NUM>TiCl<NUM>, (nBuCp)<NUM>ZrCl<NUM>, (nBuCp)<NUM>HfCl<NUM>, (nBuCp)<NUM> VCh, (nBuCp)<NUM>Ti(Me)<NUM>, (nBuCp)<NUM>Zr(Me)<NUM>, (nBuCp)<NUM>Hf(Me)<NUM>, (nBuCp)<NUM>Ti(OCH<NUM>)<NUM>, (nBuCp)<NUM>Zr(OCH<NUM>)<NUM>, (nBuCp)<NUM>Hf(OCH<NUM>)<NUM>, (nBuCp)<NUM>Ti(OEt)<NUM>, (nBuCp)<NUM>Zr(OEt)<NUM>, (nBuCp)<NUM>Hf(OEt)<NUM>, (Me<NUM>Cp)<NUM>TiCl<NUM>, (Me<NUM>Cp)<NUM>ZrCl<NUM>, (Me<NUM>Cp)<NUM>HfCl<NUM>, (Me<NUM>Cp)<NUM>VCl<NUM>, (Me<NUM>Cp)<NUM>Ti(Me)<NUM>, (Me<NUM>Cp)<NUM>Zr(Me)<NUM>, (Me<NUM>Cp)<NUM>Hf(Me)<NUM>, (Me<NUM>Cp)<NUM>Ti(OMe)<NUM>, (Me<NUM>Cp)<NUM>Zr(OMe)<NUM>, (Me<NUM>Cp)<NUM>Hf(OMe)<NUM>, (Me<NUM>Cp)<NUM>Ti(OEt)<NUM>, (Me<NUM>Cp)<NUM>Zr(OEt)<NUM>, (Me<NUM>Cp)<NUM>Hf(OEt)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>TiCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>ZrCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>HfCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>VCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Ti(Me)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Zr(Me)<NUM>, (<NUM>,<NUM>- Me<NUM>Ind)<NUM>Hf(Me)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Ti(OMe)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Zr(OMe)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Hf(OMe)<NUM>, (<NUM>,<NUM>-Me<NUM>lnd)<NUM>Ti(OEt)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Zr(OEt)<NUM>, (<NUM>,<NUM>-Me<NUM>lnd)<NUM>Hf(OCH<NUM>CH<NUM>)<NUM>, (<NUM>-MeInd)<NUM>TiCl<NUM>, (<NUM>-MeInd)<NUM>ZrCl<NUM>, (<NUM>-MeInd)<NUM>HfCl<NUM>, (<NUM>-MeInd)<NUM>VCl<NUM>, (<NUM>-MeInd)<NUM>Ti(Me)<NUM>, (<NUM>-MeInd)<NUM>Zr(Me)<NUM>, (<NUM>-MeInd)<NUM>Hf(Me)<NUM>, (<NUM>-MeInd)<NUM>Ti(OMe)<NUM>, (<NUM>-MeInd)<NUM>Zr(OMe)<NUM>, (<NUM>-MeInd)<NUM>Hf(OMe)<NUM>, (<NUM>-MeInd)<NUM>Ti(OEt)<NUM>, (<NUM>-MeInd)<NUM>Zr(OEt)<NUM>, (<NUM>-MeInd)<NUM>Hf(OEt)<NUM>, (<NUM>-arilInd)<NUM>TiCl<NUM>, (<NUM>-arilInd)<NUM>ZrCl<NUM>, (<NUM>-arilInd)<NUM>HfCl<NUM>, (<NUM>-arilInd)<NUM>VCl<NUM>, (<NUM>-arilInd)<NUM>Ti(Me)<NUM>, (<NUM>-arilInd)<NUM>Zr(Me)<NUM>, (<NUM>-arilInd)<NUM>Hf(Me)<NUM>, (<NUM>-arilInd)<NUM>Ti(OMe)<NUM>, (<NUM>-arilInd)<NUM>Zr(OMe)<NUM>, (<NUM>-arilInd)<NUM>Hf(OMe)<NUM>, (<NUM>-arilInd)<NUM>Ti(OEt)<NUM>, (<NUM>-arilInd)<NUM>Zr(OEt)<NUM>, (<NUM>-arilInd)<NUM>Hf(OEt)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>TiCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>ZrCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>HfCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>VCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Ti(Me)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Zr(Me)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Hf(Me)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Ti(OMe)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Zr(OMe)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Hf(OMe)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Ti(OEt)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Zr(OEt)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Hf(OEt)<NUM>, (<NUM>-MeFlu)<NUM>TiCl<NUM>, (<NUM>-MeFlu)<NUM>ZrCl<NUM>, (<NUM>-MeFlu)<NUM>HfCl<NUM>, (<NUM>-MeFlu)<NUM>VCl<NUM>, (<NUM>-MeFlu)<NUM>Ti(Me)<NUM>, (<NUM>-MeFlu)<NUM>Zr(Me)<NUM>, (<NUM>-MeFlu)<NUM>Hf(Me)<NUM>, (<NUM>-MeFlu)<NUM>Ti(OMe)<NUM>, (<NUM>-MeFlu)<NUM>Zr(OMe)<NUM>, (<NUM>-MeFlu)<NUM>Hf(OMe)<NUM>, (<NUM>-MeFlu)<NUM>Ti(OEt)<NUM>, (<NUM>-MeFlu)<NUM>Zr(OEt)<NUM>, (<NUM>-MeFlu)<NUM>Hf(OEt)<NUM>.

The content of transition metal of the metallocene complex defined in (I) in the catalyst of the present invention is in the range of <NUM> to <NUM>%. (II) a hybrid soluble silica, prepared by the non-hydrolytic sol-gel process;.

A hybrid soluble silica present in the catalyst of the present invention has a structure consisting of siloxane groups (SiOSi), alkoxy groups and aliphatic organic groups. In this structure, the aliphatic organic groups are covalently bonded to the silicon atoms. (III) an inorganic catalyst support;.

The inorganic catalyst support of the catalyst of the present invention is a compound belonging to the group of oxides. Examples of supports used are selected from silica, alumina, magnesia, mixed oxides of silica-alumina, silica-magnesia, alumina-magnesia and silica-magnesium chloride, modified or not with electroceptor groups such as fluorine, chloride, phosphate and sulfate.

In the catalyst of the present invention, a hybrid soluble silica is physically or chemically adsorbed on the surface of the inorganic catalyst support. The content of C, from the aliphatic organic groups of the hybrid soluble silica, in the catalyst is comprised between <NUM>% and <NUM>% relative to the mass of inorganic support. (IV) at least one aluminum-containing organometallic reagent.

The organometallic reagent containing aluminum is an aluminoxane compound of the metylaluminoxane (MAO) type, etylaluminoxane (EAO) or a compound of formula <NUM>.

Examples of organometallic reagents containing aluminum of formula <NUM> present in the catalyst of the present invention are: trimethylaluminum, triethylaluminum, tri-isobutylaluminum, tri-n-hexylaluminum and diethylaluminum chloride. The catalyst of the present invention exhibits contents of Al, from the organometallic reagent, in the range of <NUM> to <NUM>%.

Additionally, the present invention pertains to a process for obtaining supported metallocene catalysts based on a transition metal of groups <NUM> or <NUM>, comprising:.

In step (a) of the process for obtaining supported metallocene catalysts based on a transition metal of groups <NUM> or <NUM> of the present invention, a hybrid soluble silica is prepared.

A hybrid soluble silica of the present invention is obtained by a non-hydrolytic sol-gel route, where a metal halide acts as catalyst of the sol-gel reaction. This catalyst accelerates the condensation reactions of the reagents present in said reaction.

In a preferred embodiment, a hybrid soluble silica is prepared according to the following steps:.

In step (i) of the process for preparing the hybrid soluble silica, a suspension of a metal halide in an organic solvent is prepared. The concentration of metal halide in this suspension should be in the range of <NUM> to <NUM> per mL of organic solvent.

Examples of metal halides that can be used in step (i) of the process for preparing the hybrid soluble silica are selected from the group that comprises iron chloride III, aluminum chloride, titanium chloride IV and zirconium chloride IV. Iron chloride III is preferably used.

Non-limitative examples of solvents that can be used for the suspension of the metal halide are selected from the group that comprises toluene, cyclo-hexane, n-hexane, n-heptane, n-octane and/or mixtures thereof.

In step (ii) of the process for preparing the hybrid soluble silica, silicon tetrachloride is added to the suspension prepared in (i). The molar ratio of silicon tetrachloride/metal halide is in the range between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

In step (iii) of the process for preparing the hybrid soluble silica, a mixture is made containing an alkoxysilane, an organo-alkoxysilane and an organic solvent. The concentration of total silane (alkoxysilane + organo-alkoxysilane) in this mixture should be in the range of <NUM> mmol to <NUM> mmol per mL of organic solvent.

Non-limitative examples of the alkoxysilanes used in the present invention are selected from the group that comprises tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane. Tetraethoxysilane should preferably be used.

The organo-alkoxysilane has a carbon chain from <NUM> to <NUM> carbon atoms. An organo-alkoxysilane having <NUM> to <NUM> carbon atoms is preferably used.

The alkoxide grouping of said reagent should have from <NUM> to <NUM> carbon atoms. Alkoxide grouping having <NUM> carbon atom is preferably used.

Non-limitative examples of the organo-alkoxysilanes used in the present invention are selected from the group that comprises methyltriethoxysilane, propyltrimethoxysilane, octyltrimethoxysilane, hexadecyltrimethoxysilane and octadecyltrimethoxysilane.

Non-limitative examples of solvents used in step (iii) of the process for preparing the hybrid soluble silica are selected from the group that comprises toluene, cyclo-hexane, n-hexane, n-heptane, n-octane and/or mixtures thereof.

The molar ratio of organo-alkoxysilane/alkoxysilane in the mixture prepared in step (iii) may range from <NUM> to <NUM>, preferably between <NUM> and <NUM>.

In step (iv) of the process for preparing the hybrid soluble silica, the mixture prepared in (iii) is added to the suspension obtained in (ii);.

The molar ratio total silane/silicon tetrachloride used in preparing the hybrid soluble silica may range from <NUM> to <NUM>.

The temperature during the addition in step (iv) may range between the limits of <NUM> to <NUM>.

In step (v) of the process for preparing the hybrid soluble silica, the chemical reaction occurs between the reagents present in the mixture prepared in (iv).

The temperature of the reaction of step (v) may range between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

The reaction time of step (v) may range from <NUM> to <NUM>, preferably from <NUM> to <NUM>.

In step (b) of the process for obtaining supported metallocene catalysts based on a transition metal of groups <NUM> or <NUM> of the present invention, the hybrid soluble silica is reacted with an inorganic support. The inorganic support may be used in its form in natura or calcined up to a temperature limit of <NUM>. The content of hybrid soluble silica added to the inorganic support may range from <NUM>% to <NUM>% by mass of carbon per mass of inorganic support.

Non-limitative examples of solvents that can be used in step (b) of the process for preparing of the catalyst of the present invention are selected from the group that comprises toluene, cyclo-hexane, n-hexane, n-heptane and/or mixtures thereof.

The temperature of the reaction of step (b) may range between <NUM> and <NUM>, preferably between <NUM> and <NUM>. The stirring velocity is kept between <NUM> and <NUM> rpm. The temperature in step (b) may range from <NUM> to <NUM>, preferably between <NUM> and <NUM>. The reaction of step (b) is kept for a time between <NUM> and <NUM>.

In step (c) of the process for obtaining the metallocene catalysts of the present invention, the solvent is removed from the reaction product obtained in step (b) preferably by techniques of nitrogen gas flow evaporation, settling/siphoning, evaporation by reduced pressure or evaporation by heating, used in isolation or in combination.

In step (d), the product obtained in step (c) is reacted with one aluminum-containing organometallic reagent.

The content of organometallic reagent containing aluminum added to the product of step (c) may range from <NUM>% to <NUM>% by mass of aluminum per mass of product of step (c).

Examples of organometallic reagents used in step (d) are preferably selected from among metylaluminoxane, etylaluminoxane, trimethylaluminum, triethylaluminum, tri-isobutylaluminum, tri-n-hexilaluminum and diethylaluminum chloride.

Non-limitative examples of solvents that can be used in step (d) are preferably selected from among toluene, cyclo-hexane, n-hexane, n-heptane, n-octane and/or mixtures thereof.

The temperature of the reaction of step (d) may range between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

The stirring velocity in step (d) of the process is kept between <NUM> and <NUM> rpm.

The reaction of step (d) is kept for a time between <NUM> and <NUM>, specifically between <NUM> and <NUM>.

In step (e) of the process for obtaining metallocene catalysts, the solvent is removed from the reaction product obtained in step (d) preferably by techniques of nitrogen gas flow evaporation, settling/siphoning, evaporation by reduced pressure or evaporation by heating, used in isolation or in combination.

In step (f) of the process for obtaining metallocene catalysts, the product obtained in step (e) is reacted with a metallocene complex.

The metallocene used in step (f) of the process comprises a derivative compound of the following formula:.

Representative but non-limitative examples of compounds having formula <NUM> include: Cp<NUM>TiCl<NUM>, Cp<NUM>ZrCl<NUM>, Cp<NUM>HfCl<NUM>, Cp<NUM>VCl<NUM>, Cp<NUM>Ti(Me)<NUM>, Cp<NUM>Zr(Me)<NUM>, Cp<NUM>Hf(Me)<NUM>, Cp<NUM>Ti(OMe)<NUM>, Cp<NUM>Zr(OMe)<NUM>, Cp<NUM>Hf(OMe)<NUM>, Cp<NUM>Ti(OEt)<NUM>, Cp<NUM>Zr(OEt)<NUM>, Cp<NUM>Hf(OEt)<NUM>, Ind<NUM>TiCl<NUM>, Ind<NUM>ZrCl<NUM>, Ind<NUM>HfCl<NUM>, Ind<NUM>VCl<NUM>, Ind<NUM>Ti(Me)<NUM>, Ind<NUM>Zr(Me)<NUM>, Ind<NUM>Hf(Me)<NUM>, Ind<NUM>Ti(Me)<NUM>, Ind<NUM>Zr(OMe)<NUM>, Ind<NUM>Hf(OMe)<NUM>, Ind<NUM>Ti(OEt)<NUM>, Ind<NUM>Zr(OEt)<NUM>, Ind<NUM>Hf(OEt)<NUM>, Flu<NUM>TiCl<NUM>, Flu<NUM>ZrCl<NUM>, Flu<NUM>HfCl<NUM>, Flu<NUM>VCl<NUM>, Flu<NUM>Ti(Me)<NUM>, Flu<NUM>Zr(Me)<NUM>, Flu<NUM>Hf(Me)<NUM>, Flu<NUM>Ti(OMe)<NUM>, Flu<NUM>Zr(OMe)<NUM>, Flu<NUM>Hf(OMe)<NUM>, Flu<NUM>Ti(OEt)<NUM>, Flu<NUM>Zr(OEt)<NUM>, Flu<NUM>Hf(OEt)<NUM>, (MeCp)<NUM>TiCl<NUM>, (MeCp)<NUM>ZrCl<NUM>, (MeCp)<NUM>HfCl<NUM>, (MeCp)<NUM>VCl<NUM>, (MeCp)<NUM>Ti(Me)<NUM>, (MeCp)<NUM>Zr(Me)<NUM>, (MeCp)<NUM>Hf(Me)<NUM>, (MeCp)<NUM>Ti(OMe)<NUM>, (MeCp)<NUM>Zr(OMe)<NUM>, (MeCp)<NUM>Hf(OMe)<NUM>, (MeCp)<NUM>Ti(OEt)<NUM>, (MeCp)<NUM>Zr(OEt)<NUM>, (MeCp)<NUM>Hf(OEt)<NUM>, (nBuCp)<NUM>TiCl<NUM>, (nBuCp)<NUM>ZrCl<NUM>, (nBuCp)<NUM>HfCl<NUM>, (nBuCp)<NUM>VCl<NUM>, (nBuCp)<NUM>Ti(Me)<NUM>, (nBuCp)<NUM>Zr(Me)<NUM>, (nBuCp)<NUM>Hf(Me)<NUM>, (nBuCp)<NUM>Ti(OCH<NUM>)<NUM>, (nBuCp)<NUM>Zr(OCH<NUM>)<NUM>, (nBuCp)<NUM>Hf(OCH<NUM>)<NUM>, (nBuCp)<NUM>Ti(OEt)<NUM>, (nBuCp)<NUM>Zr(OEt)<NUM>, (nBuCp)<NUM>Hf(OEt)<NUM>, (Me<NUM>Cp)<NUM>TiCl<NUM>, (Me<NUM>Cp)<NUM>ZrCl<NUM>, (Me<NUM>Cp)<NUM>HfCl<NUM>, (Me<NUM>Cp)<NUM>VCl<NUM>, (Me<NUM>Cp)<NUM>Ti(Me)<NUM>, (Me<NUM>Cp)<NUM>Zr(Me)<NUM>, (Me<NUM>Cp)<NUM>Hf(Me)<NUM>, (Me<NUM>Cp)<NUM>Ti(OMe)<NUM>, (Me<NUM>Cp)<NUM>Zr(OMe)<NUM>, (Me<NUM>Cp)<NUM>Hf(OMe)<NUM>, (Me<NUM>Cp)<NUM>Ti(OEt)<NUM>, (Me<NUM>Cp)<NUM>Zr(OEt)<NUM>, (Me<NUM>Cp)<NUM>Hf(OEt)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>TiCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>ZrCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>HfCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>VCl<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Ti(Me)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Zr(Me)<NUM>, (<NUM>,<NUM>- Me<NUM>Ind)<NUM>Hf(Me)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Ti(OMe)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Zr(OMe)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Hf(OMe)<NUM>, (<NUM>,<NUM>-Me<NUM>lnd)<NUM>Ti(OEt)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Zr(OEt)<NUM>, (<NUM>,<NUM>-Me<NUM>Ind)<NUM>Hf(OCH<NUM>CH<NUM>)<NUM>, (<NUM>-MeInd)<NUM>TiCl<NUM>, (<NUM>-MeInd)<NUM>ZrCl<NUM>, (<NUM>-MeInd)<NUM>HfCl<NUM>, (<NUM>-MeInd)<NUM>VCl<NUM>, (<NUM>-MeInd)<NUM>Ti(Me)<NUM>, (<NUM>-MeInd)<NUM>Zr(Me)<NUM>, (<NUM>-MeInd)<NUM>Hf(Me)<NUM>, (<NUM>-MeInd)<NUM>Ti(OMe)<NUM>, (<NUM>-MeInd)<NUM>Zr(OMe)<NUM>, (<NUM>-MeInd)<NUM>Hf(OMe)<NUM>, (<NUM>-MeInd)<NUM>Ti(OEt)<NUM>, (<NUM>-MeInd)<NUM>Zr(OEt)<NUM>, (<NUM>-MeInd)<NUM>Hf(OEt)<NUM>, (<NUM>-arilInd)<NUM>TiCl<NUM>, (<NUM>-arilInd)<NUM>ZrCl<NUM>, (<NUM>-arilInd)<NUM>HfCl<NUM>, (<NUM>-arilInd)<NUM>VCl<NUM>, (<NUM>-arilInd)<NUM>Ti(Me)<NUM>, (<NUM>-arilInd)<NUM>Zr(Me)<NUM>, (<NUM>-arilInd)<NUM>Hf(Me)<NUM>, (<NUM>-arilInd)<NUM>Ti(OMe)<NUM>, (<NUM>-arilInd)<NUM>Zr(OMe)<NUM>, (<NUM>-arilInd)<NUM>Hf(OMe)<NUM>, (<NUM>-arilInd)<NUM>Ti(OEt)<NUM>, (<NUM>-arilInd)<NUM>Zr(OEt)<NUM>, (<NUM>-arilInd)<NUM>Hf(OEt)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>TiCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>ZrC1<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>HfCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>VCl<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Ti(Me)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Zr(Me)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Hf(Me)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Ti(OMe)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Zr(OMe)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Hf(OMe)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Ti(OEt)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Zr(OEt)<NUM>, (<NUM>,<NUM>,<NUM>,<NUM>-H<NUM>Ind)<NUM>Hf(OEt)<NUM>, (<NUM>-MeFlu)<NUM>TiCl<NUM>, (<NUM>-MeFlu)<NUM>ZrCl<NUM>, (<NUM>-MeFlu)<NUM>HfCl<NUM>, (<NUM>-MeFlu)<NUM>VCl<NUM>, (<NUM>-MeFlu)<NUM>Ti(Me)<NUM>, (<NUM>-MeFlu)<NUM>Zr(Me)<NUM>, (<NUM>-MeFlu)<NUM>Hf(Me)<NUM>, (<NUM>-MeFlu)<NUM>Ti(OMe)<NUM>, (<NUM>-MeFlu)<NUM>Zr(OMe)<NUM>, (<NUM>-MeFlu)<NUM>Hf(OMe)<NUM>, (<NUM>-MeFlu)<NUM>Ti(OEt)<NUM>, (<NUM>-MeFlu)<NUM>Zr(OEt)<NUM>, (<NUM>-MeFlu)<NUM>Hf(OEt)<NUM>.

The content of metallocene added in step (f) of the process may range from <NUM> to <NUM>% by mass of transition metal per mass of supported catalyst.

Non-limitative examples of solvents that can be used in step (f) of the process are selected from among toluene, cyclo-hexane, n-hexane, n-heptane, n-octane and/or mixtures thereof.

In a preferred embodiment, the metallocene complex can be reacted with an organometallic compound containing aluminum and subsequently added to the product obtained in step (e). The organometallic compounds that can be used are selected from among metylaluminoxane, etylaluminoxane, trimethylaluminum, triethylaluminum, tri-isobutylaluminum, tri-n-hexilaluminum and diethylaluminum chloride. The Al/M molar ratio that can be used is in the range of <NUM> to <NUM>.

The temperature of the reaction of step (f) of the process may range between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

The stirring velocity in step (f) of the process is kept between <NUM> and <NUM> rpm.

The reaction of step (f) of the process is kept for a time in the range of <NUM> to <NUM>, specifically between <NUM> and <NUM>.

In step (g) of the process for obtaining metallocene catalysts, the solvent is removed from the reaction product obtained in step (f) preferably by techniques of nitrogen gas flow evaporation, settling/siphoning, evaporation by reduced pressure or evaporation by heating, used in isolation or in combination.

The supported metallocene catalysts of the present invention are suitable for being used in a process of copolymerization of the ethylene with alpha-olefins in suspension or gas phase processes. The alpha-olefins are selected from among: propene, <NUM>-butene, <NUM>-octene and <NUM>-decene.

The supported metallocene catalysts of the present invention exhibit catalytic activity of <NUM> to <NUM> pol /g cat.

During the process of copolymerization of the ethylene with alpha-olefins, besides the supported catalyst of the present invention, a cocatalyst alkylaluminum can be used, and the preferred forms are selected from among metylaluminoxane, trimethylaluminum, triethylaluminum, tri-isobutylaluminum.

The Al/M molar ratio in the process of copolymerization of ethylene with alpha-olefins is from <NUM> to <NUM>.

The copolymers of ethylene with α-olefins, obtained with the supported metallocene catalysts of the present invention, exhibit uniform distribution of incorporated comonomer and high molar mass value in the ultra-high molar mass fraction, combined characteristics that lead to the formation of a mechanically more resistant material, with improved optical and weldability properties.

For a better understanding of the invention and of the improvements obtained, below are some comparative and realization examples, which should not be considered as limitative on the scope of the invention.

In the examples of the present invention, iron chloride (Sigma-Aldrich, <NUM>% purity), silicon tetrachloride (Merck, <NUM>% purity), tetraethoxysilane (Merck, <NUM>% purity), octadecyltrimethoxysilane (Sigma-Aldrich, <NUM>% purity), trimethylaluminum (Akzo Nobel, <NUM>% in Al in hexane), triethylaluminum (Akzo Nobel, <NUM>% in Al in hexane), tri-isobutylaluminum (Akzo Nobel, <NUM>% in Al in hexane) and metylaluminoxane (Sigma-Aldrich, <NUM>% in Al in toluene), (n-BuCp)<NUM>ZrCl<NUM> (Boulder, <NUM>% purity), silica Sylopol <NUM> (Grace) are used without prior purification.

The hexane (Merck, <NUM>% purity), the octane (Sigma-Aldrich, <NUM>%) and the <NUM>-hexene, used in the preparation of the supported metallocene catalyst and in the copolymerization of the ethylene with alpha-olefins, are dried according to conventional techniques.

All the manipulation carried out using inert nitrogen atmosphere with a maximum limit of <NUM> ppm of humidity.

<NUM> of iron chloride were suspended in <NUM> of octane. Two (<NUM>) mL (<NUM> mmol) of silicon tetrachloride was added to this suspension. A mixture containing <NUM> TEOS (<NUM> mmol) and <NUM> of ODS (<NUM> mmol) in <NUM> of octane was prepared separately. This mixture was added to the suspension of silicon tetrachloride and iron chloride in octane, under magnetic stirring and temperature of <NUM>. After the addition, the recipient was sealed and the reaction mixture was kept under magnetic stirring at <NUM> for a period of <NUM>. The FT-IR spectrum of the hybrid soluble silica prepared under the conditions of Example <NUM> (<FIG>) exhibits a centered band at <NUM>-<NUM>, which can be attributed to the asymmetrical stretching νas(Si-O) of the groups Si-O-Si. This result proves the formation of the soluble silica.

The RMN spectrum of <NUM>Si of the hybrid soluble silica, prepared under the conditions of Example <NUM> (<FIG>), exhibits two centered peaks at -<NUM> and -<NUM> ppm, which may be attributed, respectively, to the silicon types T<NUM> and T<NUM>. This result proves the link of the octadecylsilane groups in the silica structure.

<NUM> of silica Sylopol <NUM> activated at <NUM> were suspended in <NUM> of octane. To this suspension, there was added <NUM> of the solution of hybrid soluble silica (<NUM> of CC18) under mechanical stirring at <NUM> rpm and temperature of <NUM>. The suspension was left under mechanical stirring of <NUM> rpm at a temperature of <NUM> for <NUM>. After this period, the product was dried under vacuum for <NUM>.

The FTIR spectrum of the support modified of Example <NUM> (<FIG>) exhibits a centered band at, approximately, <NUM>-<NUM>, which can be attributed to asymmetrical stretching νas(CH<NUM>) of the octadecylsilane groups. This result proves the recoating of the surface of the support by the hybrid soluble silica. The elementary analysis by CHN showed a content of carbon of <NUM>% on this support modified, from the aliphatic organic groups of the hybrid soluble silica.

<FIG> exhibits the SEM images for the support modified and for the support in natura. According to <FIG>, the support modified exhibited the same morphology as the start commercial support.

Five (<NUM>) g of the support modified were suspended in <NUM> of hexane. To this suspension, there was added, drop by drop, <NUM> of a solution containing <NUM> of solution in metylaluminoxane (MAO) (<NUM>% in Al) in <NUM> of hexane (<NUM> mmol in Al), under mechanical stirring of <NUM> rpm and temperature of <NUM>. This suspension was kept under mechanical stirring of <NUM> rpm and at a temperature of <NUM> for <NUM>. After this period, the solvent was removed by evaporation with nitrogen flow. The resulting solid was then suspended in <NUM> of hexane. A catalytic solution was prepared separately by reacting <NUM> of n-BuCp<NUM>ZrCl<NUM> (<NUM> mmol) with <NUM> of solution of TMA <NUM>% (<NUM> mmol) in <NUM> of hexane. This solution was added to the suspension containing the support impregnated with MAO under stirring of <NUM> rpm and temperature of <NUM>. After mechanical stirring for <NUM>, the solvent was removed by evaporation with nitrogen flow.

The content of Zr in the supported catalyst metallocene of Example <NUM> is <NUM>% (p/p).

Five (<NUM>) g of silica Sylopol <NUM> activated at <NUM> were suspended in <NUM> of hexane. To this suspension, under mechanical stirring of <NUM> rpm and temperature of <NUM>, there was added, drop by drop, <NUM> of a solution containing <NUM> of solution of MAO (<NUM>% in Al) in <NUM> of hexane (<NUM> mmol in Al). This suspension was kept under mechanical stirring of <NUM> rpm and at a temperature of <NUM> for <NUM>. After this period, the solvent was removed by evaporation with nitrogen flow. The resulting solid when then suspended in <NUM> of hexane. A catalytic solution was prepared separately by reacting <NUM> of n-BuCp<NUM>ZrCl<NUM> (<NUM> mmol) with <NUM> of solution of TMA <NUM>% (<NUM> mmol) in <NUM> of hexane. This solution was added to the suspension containing the support impregnated with MAO under stirring of <NUM> rpm and a temperature of <NUM>. After mechanical stirring for <NUM>, the solvent was removed by evaporation with nitrogen flow.

The content of Zr in the supported catalyst metallocene of the comparative example is <NUM>% (p/p).

In a steel reactor with <NUM> of capacity, and with mechanical stirring, <NUM> of hexane was added in a nitrogen atmosphere. The temperature is adjusted to <NUM> with the assistance of a thermostatically-controlled bath. A quantity of <NUM>µL of TEA is added for washing the reactor. The wash time is at least thirty minutes and the wash temperature is <NUM>. The wash liquid is removed from the reactor by siphoning. After the wash, the reactor receives <NUM> of hexane, TIBA, supported catalyst and <NUM> of <NUM>-hexene. The concentration of Zr is <NUM> ×<NUM>-<NUM> mol/L and the ratio Al/Zr (external) of <NUM>. The ethylene pressure is adjusted to <NUM> bar and the polymerization is carried out for <NUM>.

The polymers obtained with the catalyst of the present invention and with the catalyst of the comparative example were characterized by gel permeation chromatography (GPC) and fractionation by crystallization temperature (Crystal), exhibiting the following characteristics:.

Table <NUM> shows the displacement of the curve profile to high molar masses, but a narrow distribution of the molar mass being maintained. The increase of the molar mass is more significant in the ultra-high molar mass fraction (Mz). <FIG> shows this displacement of the curve (b) to the right more evidently.

This molecular behavior will likely bring benefits in mechanical properties, with resistance to tear, piercing and impact. Maintaining the narrow distribution of molar mass may keep the level of oligomers or amorphs low in the soluble fraction, contributing to a low blockage level.

<FIG> shows the Crystaf profile for the example of this patent and the comparative polymer. The curve also showed an important displacement to lower crystallization temperatures. This means that the material has a differentiated comonomer distribution, taking it to a better level of product. The short ramifications (comonomer) were much better distributed along the chains, leading to a lower temperature of crystallinity, that is, a greater number of faults in the ethane sequence. Therefore, the formation of the crystalline structure is hindered, leading to the formation of smaller and finer crystals, and, therefore, having lower crystallization temperature.

The Crystaf revealed the trend of a material to crystallize with the reduction of the temperature in solution. The polymer produced with the catalyst of the present invention has more homogenous distribution than the polymer obtained with the comparative system.

Claim 1:
A metallocene catalyst based on a transition metal of groups <NUM> or <NUM> of the periodic table immobilized on a support modified with soluble hybrid silica, comprising:
(I)- at least one metallocene derived from a compound of formula <NUM>:

        [L]<NUM> - MQ<NUM>     formula <NUM>

wherein,
M is a transition metal of groups <NUM> or <NUM>;
Q, which may be the same or different, comprises: halogen radical, aryl radical, alkyl radical containing from <NUM> to <NUM> carbon atoms or alkoxy radical containing from <NUM> to <NUM> carbon atoms; and
L is a bulky ligand of the cyclopentadienyl, indenyl or fluorenyl type, substituted or not by hydrogen, alkyl, cycloalkyl, aryl, alkenyl, alkylaryl, arylalkyl or arylalkenyl, linked to the transition metal by bonding;
(II)- a hybrid soluble silica, prepared by a non-hydrolytic sol-gel process wherein a metal halide acts as catalyst of the sol-gel reaction;
(III)- an inorganic catalyst support modified with the hybrid soluble silica, wherein the hybrid soluble silica is obtained by means of the non-hydrolytic sol-gel route and has a structure consisting of siloxane groups (SiOSi), alkoxy groups and aliphatic organic groups, covalently bonded to the silicon atoms; and which is reacted with
(IV)- at least one aluminum-containing organometallic reagent.