Abstract: The present invention relates to an adduct comprising MgCl2, an alcohol (ROH) in which R is a C1-C10 hydrocarbon group, and a compound containing a transition metal M selected from the Groups 3 to 11 or the lanthanide or actinide groups of the Periodic Table of the Elements (new IUPAC version) in an amount such as to give a weight of M atoms lower than 10% based on the total weight of the adduct. The catalyst components that are obtained by reacting the adducts with halogenating agents show very high specific activity.

Abstract: A solid catalyst component for ?-olefin polymerization, which comprises a titanium atom, a magnesium atom, a halogen atom, a phthalic acid ester compound, and a 1,3-diether compound, wherein an amount of the 1,3-diether compound contained in the solid catalyst component is 0.1 to 3 mol per one mol of the phthalic acid ester compound contained therein; a process for producing a catalyst for ?-olefin polymerization, which comprises the step of contacting at least the above solid catalyst component, an organoaluminum compound, and an external electron donor compound with one another; and a process for producing an ?-olefin polymer, which comprises the step of homopolymerizing or copolymerizing an ?-olefin in the presence of a catalyst produced by the above process.

Abstract: The present invention relates to a new solid catalytic component, which can be used in combination with an aluminum compound as co-catalyst and optionally an external electron donor as additional co-catalyst to form a catalytic system of the Ziegler-Natta-catalyst-type. The solid catalytic system comprises titanium or vanadium compound, a compound of magnesium containing at least one halogen, a particulate porous support, and optionally an internal electron donor.

Abstract: An internal electron-donor compound selected from the 1,3-diethers of formula (I) in which R is a C1–C10 alkyl group, R1 is a linear or branched primary alkyl radical having at least three carbon atoms, optionally containing a heteroatom, and R2 is a secondary alkyl or cycloalkyl radicals different from i-propyl, optionally containing a heteroatom.

Abstract: Disclosed is a catalyst for olefin polymerization comprising [I] a solid titanium catalyst component [S] comprising titanium, magnesium, halogen and an electron donor (b), which is obtained by bringing a solid adduct consisting of a magnesium compound and an electron donor (a) into contact with an electron donor (b) and a liquid titanium compound by at least one method selected from (A) a method of contacting the materials in a suspended state in the coexistence of an inert hydrocarbon solvent and (B) a method of contacting the material plural times individed portions and [II] an organometallic compound catalyst component [M] containing a metal selected from the groups I to III in the periodic table.

Abstract: The present invention provides a novel process for preparing a catalyst useful in gas phase polymerization of olefins wherein the physical properties of the polymer and the productivity of the catalyst can be altered depending on the sequence of addition of the catalyst components. The catalyst consists of compounds of Ti, Mg, Al and optionally an electron donor supported on an amorphous support.

Abstract: Catalyst components for the polymerization of olefins CH2?CHR, wherein R is hydrogen or a hydrocarbon radical having 1–12 carbon atoms, comprising Mg, Ti, Cl, OR groups, where R is a C1–C10 alkyl group optionally containing heteroatoms, and an ether having two or more ether groups, characterized by the fact that the Mg/Ti weight ratio is lower than 3 from 2 to 6.5 the Cl/Ti weight ratio is from 1.5 to 6, the OR/Ti weight ratio is from 0.5 to 3.5 and at least 50% of the Titanium atoms are in a valence state lower than 4. The said catalyst components allow the preparation of ethylene copolymers with a low content of xylene soluble fractions.

Abstract: A process for the preparation of an olefin polymerisation catalyst comprising: a) reacting an aluminoxane and a Lewis base in an optionally halogenated hydrocarbon solvent to form a particulate suspension; b) reacting said suspension with a metallocene complex in an optionally halogenated hydrocarbon solvent; and optionally c) isolating the olefin polymerisation catalyst.

Abstract: The present invention provides a catalyst component for ethylene polymerization, a process for preparing the same, a catalyst comprising the same, and a process for polymerizing ethylene using the catalyst. The catalyst component comprises a reaction product, supported on an inorganic oxide support, of a magnesium complex, a titanium compound, an alcohol compound, and an organoaluminum compound, wherein said magnesium complex is formed by dissolving a magnesium halide in a solvent system comprising an organic epoxy compound and an organo phosphorus compound. The catalyst according to the invention is especially suitable for slurry phase polymerization of ethylene. The catalyst according to the present invention has high catalytic activity, and a good hydrogen response, with the resultant polymer having a more uniform particle size diameter and a narrow particle size distribution.

Abstract: The present invention relates to a method for preparing a solid titanium catalyst for olefin polymerization. The method for preparing a solid titanium catalyst for olefin polymerization according to the present invention comprises: preparing a magnesium compound solution by dissolving magnesium halide compound in a solvent mixture of cyclic ether and one or more of alcohol; preparing a carrier by adding titanium halide compound to said magnesium compound solution, then elevating the temperature of the solution and aging the solution to precipitate particles, and then adding titanium halide compound thereto for further reaction; preparing a catalyst by reacting said carrier with titanium compound and electron donor; and washing said catalyst with halogenated saturated hydrocarbon.

Abstract: Process for the polymerization of olefins CH2?CHR, in which R is hydrogen or a hydrocarbon radical with 1–12 carbon atoms, carried out in the presence of a catalyst component (A) comprising Mg, Ti and halogen as essential elements and of a catalyst component (B) capable to produce, under the same polymerization conditions, a polymer with an average particle size lower than that obtainable with the said catalyst component A. The said process provides polymers with increased bulk density.

Abstract: There are disclosed a process for producing a solid catalyst component and a catalyst for ?-olefin polymerization, and a process for producing an ?-olefin polymer, wherein the process for producing a solid catalyst component comprises the steps of: (1) reducing a specific titanium compound with an organomagnesium compound in the presence of an organosilicon compound having an Si—O bond (and an ester compound), thereby obtaining a solid product, and (2) contacting the solid product with a halogeno compound of the 14 group element, at least one member selected from the group consisting of an electron donor compound and an organic acid halide, and a compound having a Ti-halogen bond, thereby obtaining the solid catalyst component.

Abstract: The present invention provides a method for producing homo- and co-polymers of ethylene, or more particularly a method for producing homo- and copolymers of ethylene in the presence of (a) a solid titanium catalyst produced by preparing a magnesium solution by contact-reacting a halogenated magnesium compound with an alcohol; reacting thereto an ester compound having at least one hydroxyl group and a silicon compound having at least one alkoxy group; and adding a mixture of a titanium compound and a silicon compound; (b) organometallic compounds of Group II or III of the Periodic Table; and (c) an alkoxysilane compound and a haloalkne compound. The catalyst for homo- and co-polymerization of ethylene, produced according to the present invention, exhibits a high activity and the polymers produced by the method of the present invention using said catalyst have the advantages of exhibiting a high bulk density and a narrow molecular weight distribution.

Abstract: A process for the (co) polymerization of olefins of formula CH2?CHR wherein R is a hydrogen atom, a methyl or an ethyl radical, carried out in the presence of a system comprising (a) solid catalyst component comprising a compound of Ti or V not containing Metal-? bonds, Mg, halogen and optionally an electron donor compound; (b) an Al-alkyl compound; and (c) one or more non-polymerizing olefins in an amount up to 1.2% by mol with respect to the total olefins present in the reactor.

Abstract: The present invention provides a catalyst component used for homopolymerization or co-polymerization of ethylene, comprising at least one suitable electron donor compound supported on a composition containing magnesium and titanium, wherein the electron donor compound is selected from the group consisting of aliphatic ethers, alicyclic ethers, aromatic ethers, aliphatic ketones and alicyclic ketones, and wherein the composition containing magnesium and titanium is prepared by dissolving a magnesium compound into a solvent system to form a homogeneous solution and then contacting the solution with a titanium compound in the presence of a precipitation aid to precipitate the composition. The present invention also relates to a method for the preparation of said catalyst component and a catalyst comprising thereof, and to use of the catalyst in homopolymerization of ethylene or co-polymerization of ethylene with at least one C3–C8 ?-olefin.

Abstract: An organometallic composition which can be used as activating component in a metallocene catalyst for the (co)polymerization of ?-olefins, comprises: (A) a fluorinated di-unsaturated cyclic compound, having a relatively acid hydrogen atom, (B) an organometallic compound sufficiently basic to react with the acid hydrogen of the above compound (A), and (C) a polar aprotic organic compound, not containing metallic atoms, having a dielectric constant, in the pure state, equal to or greater than 2, and a weak coordinating capacity. Said composition allows a metallocene catalytic system of the ionic type to be obtained, with a high activity in the (co)polymerization of olefins and a reduced content of metallic residue in the polymeric product thus obtained.

Abstract: Cyclopolyenic 1,3-diethers wherein the carbon atom in position 2 belongs to a particular cyclic or polycyclic structure containing two or three unsaturations, solid catalyst components and catalysts therefrom, the catalysts comprising the reaction product of: i. a solid catalyst component containing an internal donor; ii. an Al-alkyl compound, and optionally iii. an external donor; the internal donor and/or the external donor being cyclopolyenic 1,3-diethers. The catalysts are useful for the polymerization of alpha-olefins.

Abstract: There are provided a process for producing a catalyst for ?-olefin polymerization, which comprises the step of contacting (1) a solid catalyst component having Ti, Mg and a halogen as essential components, (2) an organoaluminum compound and (3) a compound having a —C—O—C—O—C— bond group in a closed ring structure with one another; and a process for producing an ?-olefin polymer, which comprises the step of homopolymerizing or copolymerizing an ?-olefin in the presence of a catalyst for ?-olefin polymerization produced by the above process.

Abstract: Supported catalysts include a solid support such as silica that is functionalized to have inorganic acid functional groups attached thereto. Active catalyst particles are supported on the functionalized support material. The acid functionalized support material is made by reacting a solid support with an inorganic acid containing agent such as sulfuric acid or para-toluene sulfonic acid. An organic anchoring agent is used to form and anchor catalyst nanoparticles to the acid functionalized support material. The supported catalyst can be sized and shaped for use in any type of reactor, including a fixed bed or fluidized bed reactor. The methods of the present invention also include a process for the direct synthesis of hydrogen peroxide using the supported catalyst.

Abstract: A process for preparing a diether-based catalyst component in which: a) a slurry is obtained by contacting a solid support comprising a magnesium halide or a precursor thereof, one or more 1,3-diethers and a liquid phase containing a titanium compound, and b) the obtained slurry is then subjected to a solid/liquid separation step in order to isolate a diether-based catalyst component; said separation step b) being characterized in that the ratio between the solid/liquid separation velocity and the final amount of separated solid must be higher than 0.5 liter/(min·Kg).

Abstract: A metallocene catalyst may be temporarily and reversibly passivated by contact with an effective amount of a passivating compound selected from the group of oxygen, oxygen-containing compounds, and nitrogen-containing compounds.

Abstract: The present invention relates to a catalyst composition and a method for making the catalyst composition which comprises a polymerization catalyst and at least one gelling agent. The invention is also directed to the use of the catalyst composition in the polymerization of olefin(s). In particular, the polymerization catalyst system is supported on a carrier.

Abstract: The present invention relates to catalyst components for the polymerization of olefins comprising a titanium compound, having at least a Ti-halogen bond, and at least two electron donor compounds supported on a Mg dihalide, said catalyst component being characterized by the fact that at least one of the electron donor compounds is selected from ethers containing two or more ether groups which are further characterized by the formation of complexes with anhydrous magnesium dichloride in an amount less than 60 mmoles per 100 g of MgCl2 and by the failure of entering into substitution reactions with TiCl4 or by reacting in that way for less than 50% by moles, and at least another electron donor compound is selected from esters of mono or polycarboxylic acids. Said catalyst components are able to produce propylene polymers which, for high values of xylene insolubility, show a broad range of isotacticity.

Abstract: There are provided; (i) a solid catalyst component obtained by contacting a trivalent titanium atom-containing solid catalyst component precursor (C) with a halogeno compound (A) of the 13 or 14 group of elements in the periodic table of the elements and an electron donor (B), or a solid catalyst component obtained by contacting an intermediate product with a titanium-halogen bond-carrying compound (D), the intermediate product being obtained by contacting the solid catalyst component precursor (C) with a halogeno compound (A?) of the 14 group of elements in the periodic table of the elements and the electron donor (B), or a solid catalyst component comprising a magnesium atom, a titanium atom, a halogen atom and an electron donor and having a relative surface area of not more than 30 m2/g, the catalyst component being superior in a particle form, and (ii) a catalyst comprising the solid catalyst component and an organoaluminum compound, the catalyst being high in polymerization activity.

Abstract: There are disclosed a process for producing a solid catalyst component and a catalyst for ?-olefin polymerization, and a process for producing an ?-olefin polymer, wherein the process for producing a solid catalyst component comprises the steps of: (1) reducing a specific titanium compound with an organomagnesium compound in the presence of an organosilicon compound having an Si—O bond (and an ester compound), thereby obtaining a solid product, and (2) contacting the solid product with a halogeno compound of the 14 group element, at least one member selected from the group consisting of an electron donor compound and an organic acid halide, and a compound having a Ti-halogen bond, thereby obtaining the solid catalyst component.

Abstract: A solid catalyst component for olefin polymerization in which the molar ratio of residual alkoxy groups to supported titanium is 0.60 or less is obtained by reacting the following compound (a1) with the following compound (b1) at a hydroxyl group/magnesium molar ratio of 1.0 or more, reacting the reaction mixture with the following compound (c1) at a halogen/magnesium molar ratio of 0.20 or more, reacting the resultant reaction mixture with the following compounds (d1) and (e) at a temperature of 120° C. or higher but 150° C.

Abstract: A MgCl2.mEtOH.nH2O adducts, where 3.4<m≦4.4, 0≦n≦0.7, characterized by an X-ray diffraction spectrum, taken under the condition set forth above, in which, in the range of 2&thgr; diffraction angles between 5° and 10°, at least two diffraction lines are present at diffraction angles 2&thgr; of 9.3±0.2°, and 9.9±0.2°, the most intense diffraction lines being the one at 2&thgr; of 9.3±0.2°, the intensity of the other diffraction line being less than 0.4 times the intensity of the most intense diffraction line. Catalyst components obtained from the adducts of the present invention are capable to give catalysts for the polymerization of olefins characterized by enhanced activity and/or porosity with respect to the catalysts prepared from the adducts of the prior art.

Abstract: The present invention relates to an adduct comprising MgCl2, an alcohol (ROH) in which R is a C1-C10 hydrocarbon group, and a compound containing a transition metal M selected from the Groups 3 to 11 or the lanthanide or actinide groups of the Periodic Table of the Elements (new IUPAC version) in an amount such as to give a weight of M atoms lower than 10% based on the total weight of the adduct. The catalyst components that are obtained by reacting the adducts with halogenating agents show very high specific activity.

Abstract: A method of making a solid procatalyst composition for use in a Ziegler-Natta olefin polymerization catalyst composition, said method comprising: contacting a solid precursor composition comprising magnesium, titanium, and alkoxide moieties with a titanium halide compound and an internal electron donor in any order, in a suitable reaction medium to prepare a solid procatalyst composition, separating the solid procatalyst from the reaction medium, further exchanging residual alkoxide functionality of the solid procatalyst composition for chloride functionality by contacting the same two or more times with benzoyl chloride halogenating agent under metathesis conditions for a period of time sufficient to prepare a solid procatalyst composition having a decreased alkoxide content compared to the alkoxide content of the solid procatalyst composition before said exchange, and recovering the solid procatalyst composition.

Abstract: Cyclopolyenic 1,3-diethers wherein the carbon atom in position 2 belongs to a particular cyclic or polycyclic structure containing two or three unsaturations, solid catalyst components and catalysts therefrom, the catalysts comprising the reaction product of:

Abstract: Process for preparing an olefin polymerisation catalyst component in the form of particles having a predetermined size range, said process comprising the steps of a) preparing a solution of a complex of a Group 2 metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid reaction medium; b) adding said solution of said complex to at least one compound of a transition material to produce an emulsion, the dispersed phase of which contains more than 50 mol % of the Group 2 metal in said complex; c) agitating the emulsion, optionally in the presence of an emulsion stabilizer, in order to maintain the droplets of said dispersed phase within the average size range 5 to 200 m; d) solidifying said droplets of the dispersed phase; and e) recovering the solidified particles of the olefin polymerisation catalyst component, wherein a turbulence minimizing agent (TMA) is added to the reaction mixture before solidifying said droplets of the disperse

Abstract: A process for preparing a diether-based catalyst component in which: a) a slurry is obtained by contacting a solid support comprising a magnesium halide or a precursor thereof, one or more 1,3-diethers and a liquid phase containing a titanium compound, and b) the obtained slurry is then subjected to a solid/liquid separation step in order to isolate a diether-based catalyst component; said separation step b) being characterized in that the ratio between the solid/liquid separation velocity and the final amount of separated solid must be higher than 0.5 liter/(min.Kg).

Abstract: The present invention is to provide a composite carrier, which is spheric particles obtainable by contacting magnesium halide with one or more electron donor compounds to form a solution, then mixing the solution with silica material having an average particle size of less than 10 microns to form a mixture, and drying the mixture through spray drying process. The present invention is also to provide a catalyst component comprising said composite carrier. When the catalyst component is used together with a cocatalyst component in propylene polymerization, it exhibits higher polymerization activity and stereospecificity, and can be used to prepare high impact resistant ethylene-propylene copolymer having high ethylene content.

Abstract: A process for polymerizing olefins using a catalyst system comprising a conventional Ziegler-Natta catalyst and an external election donor selected from the group consisting of diethers and combinations thereof. The catalyst system comprises a Ziegler-Natta catalyst having a transition metal compound generally represented by the formula: MR′x where M is a transition metal, R′ is a halogen or a hydrocarboxyl, and x is the valence of the transition metal. The transition metal compound can be TiCl4. The Ziegler-Natta catalyst may comprise an internal electron donor, such as phthalate. The catalyst system further includes an external electron donor selected from the group consisting of diethers and a co-catalyst selected from the group of organoaluminum compounds. In one embodiment, the external electron donor is 2,2-diisobutyl-1,3-dimethoxypropane, and the co-catalyst is triethylaluminum.

Abstract: The present invention relates to a method for producing a polymer and copolymer of ethylene, and more particularly to a method for producing an ethylene polymer and copolymer by reacting a compound of an organic metal of Group 2, 12, or 13 on the periodic table of elements with an alkoxy silane compound in the presence of a titanium catalyst, the said titanium catalyst being produced by a process of preparing a magnesium compound by contact-reacting a halogenated magnesium compound and alcohol, of reacting the said solution with an ester compound which contains at least one hydroxy group and a silicon compound containing an alkoxy group, and also of reacting it with a solid matter obtained by reaction of a mixture of a titanium compound and a silicon compound with a titanium compound.

Abstract: The present invention relates to a solid complex titanium catalyst for homo-polymerization and co-polymerization of &agr;-olefin, obtained by (i) producing a solution of a magnesium compound by dissolving a magnesium compound and a compound of IIIA Group of the Periodic Table in a solvent mixed with cyclic ether, one or more types of alcohol, a phosphorous compound, and an organosilane, (ii) precipitating the solid particles by reacting said magnesium solution with a compound of a transition metal, a silicon compound, or the mixture thereof, and (iii) reacting said precipitated solid particles with a titanium compound and an electron donor. The catalyst of the present invention is of large particle size, narrow particle distribution, and high catalytic activity, while the polymers obtained with the use of this catalyst are of excellent stereoregularity.

Abstract: Disclosed is a preparation method of titanium catalyst for olefin polymerization, the method comprising (1) preparing magnesium compound solution by resolving non-deoxidative magnesium halide and IIIA group atom compound in a solvent mixture of cyclic ether, at least one alcohol, phosphorus compound and organosilane with or without hydrocarbon solvent; (2) reacting said magnesium compound solution with titanium compound, silicon compound, tin compound or mixture thereof to produce a support; and (3) reacting said support with titanium compound and electron donor to produce solid complex titanium catalyst, wherein the particle size and particle size distribution f said catalyst are regulated by controlling solubility of the reactants in said steps (2) and/or (3).

Abstract: A supported catalyst composition comprising the reaction product of i) a magnesium halide, ii) a solvent, iii) an electron donor compound, iv) and a transition metal compound; an inert support; and a cocatalyst composition wherein the supported catalyst is substantially free of other alcohols and wherein the molar ratio of the first alcohol to magnesium is less than or equal to 1.9. Methods of making supported catalyst compositions and methods of making polymers with supported catalysts.

Abstract: A process for polymerizing olefins using a catalyst system comprising a conventional Ziegler-Natta catalyst and an external election donor selected from the group consisting of diethers and combinations thereof. The catalyst system comprises a Ziegler-Natta catalyst having a transition metal compound generally represented by the formula: MR′x where M is a transition metal, R′ is a halogen or a hydrocarboxyl, and x is the valence of the transition metal. The transition metal compound can be TiCl4. The Ziegler-Natta catalyst may comprise an internal electron donor, such as phthalate. The catalyst system further includes an external electron donor selected from the group consisting of diethers and a co-catalyst selected from the group of organoaluminum compounds. In one embodiment, the external electron donor is 2,2-diisobutyl-1,3-dimethoxypropane, and the co-catalyst is triethylaluminum.

Abstract: A new synthesis of a Ziegler-Natta catalyst uses a multi-step preparation that includes treating a magnesium dialkoxide compound with two halogenating/titanating agents, the second stronger than the first, an organoaluminum preactivating agent, and a heat treatment. The catalyst may be used in the polymerization of olefins, particularly ethylene, to control the molecular weight distribution of the resulting polyolefins.

Abstract: Process for the polymerization of olefins CH=CHR, in which R is hydrogen or a hydrocarbon radical with 1-12 carbon atoms, carried out in the presence of a catalyst component (A) comprising Mg, Ti and halogen as essential elements and of a catalyst component (B) capable to produce, under the same polymerization conditions, a polymer with an average particle size lower than that obtainable with the said catalyst component A. The said process provides polymers with increased bulk density.

Abstract: This process for preparing a catalyst support for the homopolymerization or copolymerization of ethylene and &agr;-olefins is characterized in that at least one organochlorine compound and a premix of at least one alkylmagnesium and of at least one organoaluminum compound chosen from aluminoxanes, aluminosiloxanes and alkylaluminums are reacted together, in the presence of at least one aliphatic diether as electron donor.

Abstract: Catalyst component for the polymerization of olefins obtainable by contacting: (i) a magnesium halide, or a suitable precursor; (ii) a monofunctional electron donor compound (MD) selected from ethers, esters, amines or ketones, used in such amounts to have Mg/MD molar ratios of at least 50; (iii) a titanium compound of formula Ti(ORI)n-yXy, where n is the valence of titanium, y is a number between 1 and n, X is halogen, and RI is a C1-C15 hydrocarbon group and, optionally, (iv) an electron donor compound (ED). The said catalyst component shows improved activity in the polymerization of olefins.

Abstract: A process (I) for producing an &agr;-olefin polymerization catalyst whereby (1) a titanium compound is reduced by an organomagnesium compound in the presence of an organosilicon compound to produce a reduction solid, (2) the reduction solid is aged to produce a solid product, (3) the solid product is contacted with an ether compound, titanium tetrachloride and an organic acid halide compound, to produce an organic acid halide-treated solid, (4) the organic acid halide-treated solid is contacted with a mixture of an ether compound, titanium tetrachloride and an ester compound, or with a mixture of an ether compound and titanium tetrachloride to produce a solid catalyst component containing a titanium compound, and (5) the solid catalyst component is contacted with an aluminum compound and an electron donor compound to produce a catalyst for &agr;-olefin polymerization. A process (II) for producing an &agr;-olefin polymer using a catalyst produced by process (I).

Abstract: An olefin polymerization catalyst is described which includes: (A) a solid catalyst component being prepared by copulverizing a magnesium compound, an aluminum compound, an electron donor and a titanium compound, and (B) an organoaluminum compound. The present invention is also directed to a process for preparing polyolefins using the aforesaid catalyst system to polymerize olefins.

Abstract: A method for making a solid catalyst component for use in a Ziegler-Natta catalyst includes combining a porous particulate support with a magnesium source in a hydrocarbon solvent to form a mixture, the magnesium source including a hydrocarbon soluble organomagnesium compound and a hydrocarbon insoluble anhydrous inorganic magnesium-halogen compound. The organomagnesium compound is halogenated and the mixture is reacted with a titanium compound or vanadium compound to form the solid catalyst component. The solid catalyst component is then recovered and combined with an organoaluminum cocatalyst to form a Ziegler-Natta catalyst which is advantageously used for the polymerization of olefins, particularly alk-1-enes such as ethylene, propylene, 1-butene, and the like. The catalyst can optionally include internal and external electron donors.

Abstract: The present invention provides a catalyst component used for homopolymerization or co-polymerization of ethylene, comprising at least one suitable electron donor compound supported on a composition containing magnesium and titanium, wherein the electron donor compound is selected from the group consisting of aliphatic ethers, alicyclic ethers, aromatic ethers, aliphatic ketones and alicyclic ketones, and wherein the composition containing magnesium and titanium is prepared by dissolving a magnesium compound into a solvent system to form a homogeneous solution and then contacting the solution with a titanium compound in the presence of a precipitation aid to precipitate the composition. The present invention also relates to a method for the preparation of said catalyst component and a catalyst comprising thereof, and to use of the catalyst in homopolymerization of ethylene or co-polymerization of ethylene with at least one C3-C8 &agr;-olefln.

Abstract: There are provided (I) a process for producing a catalyst for &agr;-olefin polymerization, which comprises the steps of:

Abstract: A catalyst system for the (co)polymerization of propylene contains (A) a solid catalyst component comprising titanium, magnesium, halogen and a 1,3-diether; (B) an organic aluminum compound; and optionally (C) an organic silicon compound. In comparison with the prior art, stereospecificity of the polymer prepared by using the catalyst system of this invention evenl containing no external electron-donor is greater than 99%. Also, the activity of the catalyst system and hydrogen gas adjustability on the molecular weight of the polymer do not significantly decrease.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a complexing agent, hypophosphorous acid or its metal salt, water and optionally a solvent. The complexing agent can be hydroxycarboxylic acid, alkanolamines, aminocarboxylic acids, or combinations of two or more thereof. The solvent can be water, ethanol, propanol, isopropanol, butanol, ethylene glycol, propylene glycol, isopropylene glycol, butylene glycol, 1-methyl propylene glycol, pentylene glycol, or combinations of two or more thereof. The titanium compound can be combined with a zirconium compound. Also disclosed is a process for using the composition for producing an ester or a polyester. The process comprises contacting a carbonyl compound, in the presence of the compositions, with an alcohol under a condition suitable for esterification, transesterification, polymerization, or combinations of two or more thereof.