Abstract: Catalysts that have been preactivated and/or prepolymerized are disclosed whereby a magnesium and titanium-containing procatalyst component is contacted with a co-catalyst and an external electron donor (and optionally with an olefin monomer to prepare a prepolymerized catalyst) prior to polymerization to form a preactivated and/or prepolymerized catalyst. The preactivated and/or prepolymerized catalyst then is separated from the mixture, and dried to form a solid preactivated and/or prepolymerized catalyst. This dried catalyst then can be stored and subsequently shipped to a polymerization site where it can be used in gas phase polymerization. The preactivated and/or prepolymerized catalyst can be used in gas phase polymerization as extremely high activity catalysts, and do not cause a rapid rise in reaction temperature causing overheating, undesirable formation of agglomerates, coagulation of polymer, and ultimately, reactor failure.

Abstract: Catalyst systems of the Ziegler-Natta type, which are suitable for the polymerization of olefins are prepared by:

Abstract: Isoblock polymers of 1-olefins with a narrow molecular weight distribution are obtained when 1-olefins are polymerized using a catalyst consisting of a chiral metallocene, containing bridges, of formula I: and an aluminoxane. The polymers have rubber-like properties.

Abstract: The present invention is related to diimino compounds of formulae (I) R2—N═C(R1)(R3)nC(R1)═N—R2 and (II) (R1)2C═N—(CR24)m—N═C(R1)2 functionalized with at least one siloxy group. Said diimino compounds are useful for obtaining a solid catalyst component for polymerizing olefins wherein the diimino compound of formulae (I) or (II) is bonded to a porous inorganic support and to a transition metal selected from groups 8, 9 and 10 of the periodic table. This invention also relates to a process for preparing said diimino compounds of formulae (I) or (II), to a process for obtaining said solid catalyst component comprising the combination of the diimino compound and a porous inorganic support. Further, the invention also relates to the use of said solid catalyst in combination with a cocatalyst to polirnenrze olefins.

Abstract: The present invention provides a catalyst system that exhibits unexpected control of desired properties in copolymer product. The catalyst system includes a conventional supported Ziegler-Natta catalyst in combination with an electron donor described by the formula: wherein R1 is a linear alkyl group attached to the silicon atom; R2 and R3 are alkyl or aryl groups and R4 is a linear alkyl attached to the silicon atom, R1 and R4 are the same or different. R1 and R4 are preferably linear carbon groups of 4-13 carbon atoms, more preferably 4-7 carbon atoms; most preferably R1 and R4 are the same and are n-butyl groups. The system exhibits good control over the melt flow index of the copolymer products.

Abstract: The present invention concerns a method for the copolymerization of conjugated diolefins and vinyl-aromatic monomers in the presence of rare-earth catalysts and the use of the copolymers in rubber mixtures for tire applications.

Abstract: The present invention relates to a solid catalyst component for &agr;-olefin polymerization having a narrow particle size distribution of not less than 6.0 in terms of the value of N in a Rosin-Rammler function of particle size distribution and giving a catalytic activity of not less than 10,000 ((g-polymer produced/g-solid catalyst component)/hour) in polymerization. According to the present invention, there can be provided a solid catalyst component for &agr;-olefin polymerization capable of giving a poly-&agr;-olefin having the high bulk density and favorable particle properties with high catalytic activity.

Abstract: The invention relates to high-activity catalysts for olefin polymerization, to efficient methods for producing them, and to efficient methods of using the catalysts for producing high-quality polyolefins. The olefin polymerization with the catalysts does not require a large amount of an organic aluminium compound, and the residual metal in the polyolefins produced is much reduced. The catalysts are characterized by containing a product as prepared by contacting any of clay, a clay mineral and an ion-exchanging layered compound, an organic silane compound, and water with each other, or by containing a silane compound-processed clay.

Abstract: This invention provides catalyst composition for polymerizing at least one monomer to produce a polymer, wherein said catalyst composition comprises as organometal compound, as organoaluminum compound, and a fluorided solid oxide compound.

Abstract: Catalytic systems particularly suitable for the polymerization of &agr;-olefins containing from two to 20 carbon atoms, as well as for the copolymerization of ethylene with &agr;-olefins containing from three to 20 carbon atoms, dienes, and cycloalkenes in processes wherein the catalyst is suspended in a solvent, in processes in gas phase, as well as in mass polymerization processes at high temperatures and pressures, are disclosed. The catalytic system is a mixture of a catalyst component A and a co-catalyst component B. The catalyst component A is formed by a functionalized inorganic porous oxide, by an organoaluminium compound and by an organometallic compound of a metal of the groups 3, 4, 5, or 6 of the periodic table. Functionalization of the inorganic oxide is by introduction of functional groups to be used to strongly fix the organoaluminium compound and the organometallic compound.

Abstract: A propylene/ethylene/&agr;-olefin terpolymer characterized in that i) there is from 0.01 mol % to less than 15 mol % of a comonomer unit with a molar ratio of ethylene units/C4-C20 &agr;-olefin units being in the range of from 6.5×10−4 to 0.99, and from more than 85 mol % to not more than 99.99 mol % of a propylene unit with 2,1- and 1,3-propylene units being in the range of from 0 to 1 mol %, in a polymer chain determined by 13C-NMR spectroscopy; ii) a weight average molecular weight (Mw) determined by GPC is in the range of from 40,000 to 1,000,000; and iii) the amount of the component eluted in o-dichlorobenzene at a temperature of not higher than 40° C. is not more than 10 % by weight based on the total weight of the terpolymer and the amount of the component eluted in o-dichlorobenzene within the ±10° C. range of an elution peak temperature is not less than 75 % by weight based on the weight of the component eluted at a temperature of higher than 0° C.

Abstract: A method of polymerizing olefins with a catalyst component which comprises 1) the reaction product of a magnesium alkoxide of the formula M(OR)2, wherein M is magnesium, O is oxygen, R is a hydrocarbyl having from 1 to 20 carbons atoms, and a halogenating agent; 2) an electron donor wherein the electron donor is diethyl phthalate or di-isobutyl phthalate; 3) a titanating agent. The catalyst component is activated with an organoaluminum cocatalyst. An external donor, specifically dicyclopentyl dimethoxysilane or cyclohexylmethyldimethoxy silane, can be added as a stereoselectivity control agent. The activated catalyst is used in the polymerization of olefins, particularly propylene, to obtain a polymer product with a broad molecular weight distribution.

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

Abstract: A method for preparing an &agr;-olefin polymer comprising the step of polymerizing or copolymerizing an &agr;-olefin in the presence of a catalyst containing a solid catalyst constituent (A) which contains magnesium, titanium, a halogen element and an electron donor, an organoaluminum compound constituent (B), an organosilicon compound constituent (C) represented by the following general formula (1); and an organosilicon compound constituent (D) represented by the following general formulas (2) or (3) to prepare an &agr;-olefin polymer RnSi(OR)4−n  (1) wherein R is a hydrocarbon group having 1 to 8 carbon atoms, n is integer of 1 or 2; wherein R1 is a hydrocarbon group having 1 to 8 carbon atoms, R2 is a hydrocarbon group having 1 to 8 carbon atoms, a hydrocarbylamino group having 2 to 24 carbon atoms, or a hydrocarbylalkoxy group having 1 to 24 carbon atoms, R3N is a polycyclic amino group having 7 to 40 carbon atoms, wherein the carbon atoms and the nitrogen atom form a c

Abstract: The present invention provides a method for producing a catalyst for the production of an ultra high molecular weight polyethylene and also a method for preparation of an ultra high molecular weight polyethylene with the use of said catalyst. The catalyst of the present invention is prepared by a process comprising: (i) producing a magnesium compound solution by contact-reacting a magnesium compound and an aluminum or boron compound with alcohol; (ii) contact-reacting the said solution with an ester compound containing at least one hydroxy group and a silicon compound containing an alkoxy group; and (iii) producing a solid titanium catalyst by adding a mixture of a titanium compound and a silicon compound thereto. The catalyst prepared by the present invention has excellent catalytic activity, and it helps to produce an ultra-high molecular weight polyethylene with large bulk density and narrow particle distribution without too large and minute particles.

Abstract: The molecular weight of polyolefins produced using selected late transition metal complexes of bidentate ligands may be lowered by carrying out the polymerization in the presence of hydrogen, a selected silane, or CBr4.

Abstract: A solid catalyst for olefin polymerization, obtained by reacting a least one of a hydropolysiloxane compound, having the formula R1aHbSiO(4−a−b)/2, a silane compound of formula R2cSi(OH)4−c, and condensates of the silane, with a compound of formula (MgR32)p.(R3MgX)q to form a reaction product. The reaction product is reacted with an alcohol, having 1 to 4 carbon atoms, to obtain an intermediate product. The intermediate product, is then reacted with water to obtain reaction product. An organoaluminum oxy compound and a metallocene compound are carried on the solid reaction product. The solid catalyst may be used for olefin polymerization. The catalyst requires no deashing treatment and produces a polymer having high bulk density and narrow particle size distribution. Thus the solid catalystenables control of particle size of the polymer in a simple easy manner, and shows no adhesion of polymer onto the inner wall of autoclave.

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 II or m 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: A process for preparing syndiotactic vinylidene aromatic polymers comprising contacting one or more vinylidene aromatic monomers with a concentrated catalyst premix composition comprising a Group 4 metal complex and an activating cocatalyst.

Abstract: There are provided (i) a catalyst component (C), (ii) an olefin polymerization catalyst, and (iii) a process for producing an olefin polymer. The catalyst being obtained by contacting a solid catalyst component (A), an organoaluminum compound (B) and the catalyst component (C) of an organosilicon compound represented by the following formula (1), wherein n is 1 or 2, R1 to and R6 are independently of one another a hydrogen or halogen atom or a hydrocarbon group, or may be bonded with one another to form a ring, R7 is a hydrocarbon group, and when n is 2, two R1s, R2s, R3s, R4s, R5s and R6s may be the same or different.

Abstract: This invention provides catalyst compositions that are useful for polymerizing at least one monomer to produce a polymer. This invention also provides catalyst compositions that are useful for polymerizing at least one monomer to produce a polymer, wherein said catalyst composition comprises a post-contacted organometal compound, a post-contacted organoaluminum compound, and a post-contacted fluorided silica-alumina.

Abstract: A process for preparing syndiotactic monovinylidene aromatic polymers comprising contacting one or more monovinylidene aromatic monomers with a catalyst composition comprising a Group 4 metal complex and an activating cocatalyst composition comprising an aluminoxane and an electrophilic borane compound.

Abstract: A prepolymerization catalyst for use in a gas phase polymerization of an olefin or combinations of olefins which comprises (A) a solid catalyst component comprising magnesium, halogen, titanium and an electron donor and having a weight-average particle diameter of 15 to 45 &mgr;m, (B) at least one organoaluminum compound and (C) a prepolymer of an ethylene and/or at least one &agr;-olefin, wherein the molar ratio of aluminum to titanium in the prepolymerization catalyst (Al/Ti ratio) is 3 to 11 (mol/mol), the weight ratio of the prepolymerization catalyst to the solid catalyst component (prepolymerization catalyst/solid catalyst component) is 2 to 35 (g/g), the content of volatile materials (VM) in the prepolymerization catalyst is 2.0% by weight or less, and the intrinsic viscosity [&eegr;] measured in tetralin at 135° C. is 2.0 dl/g or less, and a process for a production thereof.

Abstract: One aspect of the present invention relates to a catalyst system for use in olefinic polymerization, containing a solid titanium catalyst component; an organoaluminum compound having at least one aluminum-carbon bond; and an organosilicon compound comprising a (cycloalkyl)methyl group. Another aspect of the present invention relates to a method of making a catalyst for use in olefinic polymerization, involving the steps of reacting a Grignard reagent having a (cycloalkyl)methyl group with an orthosilicate to provide an organosilicon compound having a (cycloalkyl)methyl moiety; and combining the organosilicon compound with an organoaluminum compound having at least one aluminum-carbon bond and a solid titanium catalyst component to form the catalyst.

Abstract: A catalyst system in which the ratio of rac isomer to meso isomer of the metallocene is from 1:10 to 2:1 can be used for the polymerization of olefins.

Abstract: A polypropylene resin composition exibiting a high melt tension and superior moldability, which can be molded efficiently by a high-speed molding into scarcely deformable larger molded articles of better appearance with high stiffness and which comprises polypropylene as a main component and has the following characteristic features 1) to 4), namely, 1) that a melt flow rate (MFR, determined at 230° C. under a load of 2.16 kg) is in the range of 0.01 to 5 g/10 min., 2) that a content of a high molecular weight polypropylene exhibiting an intrinsic viscosity [&eegr;], determined at 135° C. in decalin, of 8-13 dl/g is in the range of 15 to 50% by weight, 3) that a gel areal density in number is 3,000/450 cm2 or less and 4) that a molecular weight distribution determined by gel permeation chromatography (GPC) is 6-20, as expressed by Mw/Mn, and is 3.5 or higher, as expressed by Mz/Mw.

Abstract: The present invention has its object to provide an isobutylene group block copolymer containing a highly reactive alkenyl group with a high rate of introduction of an alkenyl, and process for producing the same. An alkenyl-group-containing isobutylene group block copolymer comprising a polymer block derived from (a) a monomer component containing isobutylene group as a predominant monomer and (b) a monomer component not containing isobutylene group as a predominant monomer, in which said block copolymer has an alkenyl group of the following general formula (1).

Abstract: The present invention relates to the use of at least one acid and at least one base and/or at least one reductant and at least one oxidant that when used with a polymerization catalyst in a polymerization process results in the controllable generation of a catalyst inhibitor that renders the polymerization catalyst substantially or completely inactive.

Abstract: A mixed metal-containing precursor is disclosed whereby the precursor includes: a) MgZrMx where M is selected from one or more metals having a +3 or +4 oxidation state, x is from 0 to about 2, and where the molar ratio of magnesium to the mixture of zirconium and M is within the range of from about 2.5 to 3.6; and b) at least one moiety complexed with component a) selected from the group consisting of alkoxide groups, phenoxide groups, halides, hydroxy groups, carboxylate groups, amide groups, and mixtures thereof A polymerization procatalyst prepared from the mixed metal containing precursor, methods of making the precursor and procatalyst, as well as polymerization methods using the procatalyst also are disclosed.

Abstract: A process for preparing polyolefins by polymerizing or coploymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound is provided.

Abstract: A novel process for producing homopolymers and copolymers of ethylene which involves contacting ethylene and/or ethylene and at least one or more other olefin(s) under polymerization conditions with a Ziegler-Natta type catalyst. at least one halogenated hydrocarbon, at least one compound of the formula XnER3-n as a co-catalyst and at least one compound containing at least one carbon-oxyen-carbon linkage (C—O—C) of the formula R1—O(—R2—O)n—R3 as an external electron donor. Also provided are films and articles produced therefrom.

Abstract: The present invention relates to a process for polymerizing olefin(s) utilizing a cyclic bridged metallocene-type catalyst system to produce enhanced processability polymers.

Abstract: A method to prepare a polyolefin in the presence of a catalyst comprising: (A) a solid catalyst component prepared by reacting a homogenous solution consisting of (i) at least one member selected from the group consisting of metal magnesium and a hydroxylated organic compound, and oxygen-containing organic compounds of magnesium, (ii) at least one oxygen-containing organic compound of titanium and (iii) at least one silicon compound, first with (iv) at least one first organoaluminum halide compound of the formula: AlR5zX3−z  wherein R5 is a hydrocarbon group having from 1 to 20 carbon atoms, X is a halogen atom, and 1≦z≦2, and wherein the atomic ratio of gram atoms of Al in the component (iv) to gram atoms of Mg in the component (i) (Al/Mg) is from 0.1 to 2.

Abstract: A process for producing an olefin polymer using a catalyst in which (A) is a solid catalyst component which includes magnesium, titanium, halogen and an electron donative compound as essential constituents; (B) is an organoaluminum component; and (C) is at least two electron donative compounds (&agr;) and (&bgr;), wherein the pentad stereoregularity of a xylene insoluble fraction of a homopolyproylene is 0<mmrr/mmmm≦0.0068 when electron donative compound (&agr;) is used in combination with (A) and (B), and the pentad stereoregularity of a xylene insoluble fraction homoproplyene of a is 0.0068<mmrr/mmmm ≦0.0320 when electron donative compound (&bgr;) is used in combination with (A) and (B). A polypropylene produced in the process can be used to obtain a biaxially oriented film. (A) and (B). A polypropylene produced in the process can be used to obtain a biaxially oriented film.

Abstract: A polypropylene composition comprising 0.001 to 10 parts by weight of a polyethylene having an intrinsic viscosity [&eegr;E] of 0.01 to less than 15 dl/g s measured in tetralin at 135° C. and 100 parts by weight of a polyolefin comprising at least polypropylene, wherein the polyethylene is finely dispersed as particles with a number average particle diameter of, e.g., 1 to 5000 nm in the polyolefin comprising at least polypropylene. By virtue of the above constitution, the polypropylene composition has excellent transparency and rigidity, is free from the creation of a sweeper roll flow mark in the preparation of a film and substantially free from a neck-in phenomenon of a film, and has high productivity.

Abstract: Solid catalyst components for the polymerization of olefins, comprising titanium, magnesium and a compound of general formula (I), wherein R1 and R2 may be the same or different and each represents a linear or branched hydrocarbon group having 1 to 20 carbon atoms, and n is an integer of 1 to 10, as an electron donor, which are combined with organoaluminum compounds to form polymerization catalysts for the production of olefin polymers. This electron donor has no problems of safety and hygiene, and is inexpensive and easily synthesized. This compound can provide highly active and highly stereoregular solid catalyst components for the polymerization of olefins, catalysts for the polymerization of olefins, and processes for producing olefin polymers.

Abstract: Catalysts that have been preactivated and/or prepolymerized are disclosed whereby a magnesium and titanium-containing procatalyst component is contacted with a co-catalyst and an external electron donor (and optionally with an olefin monomer to prepare a prepolymerized catalyst) prior to polymerization to form a preactivated and/or prepolymerized catalyst. The preactivated and/or prepolymerized catalyst then is separated from the mixture, and dried to form a solid preactivated and/or prepolymerized catalyst. This dried catalyst then can be stored and subsequently shipped to a polymerization site where it can be used in gas phase polymerization. The preactivated and/or prepolymerized catalyst can be used in gas phase polymerization as extremely high activity catalysts, and do not cause a rapid rise in reaction temperature causing overheating, undesirable formation of agglomerates, coagulation of polymer, and ultimately, reactor failure.

Abstract: Olefin polymerization catalysts are formed from:

Abstract: A catalyst composition that is the combination of or the reaction product of ingredients comprising a iron-containing compound, an organomagnesium compound, and a silyl phosphonate.

Abstract: Provided area catalyst for polymerizing olefinic monomers, which comprises (a) a transition metal compound, (b) at least one member selected from clay, clay minerals and ion-exchanging layered compounds, (c) a silane compound, and optionally (d) an alkylating agent; a catalyst for polymerizing olefinic monomers, which comprises (a) a transition metal compound, (b) at least one member selected from clay, clay minerals and ion-exchanging layered compounds, (c) a silane compound, and optionally (e) an organic aluminum compound, and further optionally (d) an alkylating agent; and a method for producing olefinic polymers or styrenic polymers, which comprises homopolymerizing or copolymerizing olefinic or styrenic monomers in the presence of the catalyst for polymerizing olefinic monomers. The method does not require a large amount of aluminoxane, and the catalyst to be used therein has high polymerization activity.

Abstract: In olefin polymer production, for which is used a metallocene-type catalyst having a double-crosslinked indenyl or substituted indenyl group, a small amount of hydrogen is added to the polymerization system. Concretely, hydrogen is added thereto so that the hydrogen concentration in the olefin being polymerized could be from 0.01 to 10 mol % or hydrogen could be in the polymerization system in an amount of from 10 to 20000 mols relative to one mol of the transition metal in the metallocene-type catalyst. Hydrogen added to the olefin polymer production system enhances the polymerization activity of the catalyst used, and the catalyst could exhibit high activity in the presence of hydrogen.

Abstract: Disclosed is propylene copolymers produced by the aid of a specific metallocene catalyst system, wherein a percentage of mis-insertion in the copolymer is highly controlled and the copolymers possess beat-resisting property and a high melt strength and a low MFR and are narrow in molecular weight distribution excellent in particulate properties as well as a process for producing the copolymers possessing high steroregularity at a practical polymerzation temperature. The gist of the present invention resides in production of propylene copolymers wherein copolymerization with &agr;,&ohgr;-diene is carried out by the aid of a supported-type catalyst system comprised predominantly of the following compound (A), (B), (C) and (D) at a temperature above 45° C.: the compound (A): a specific metallocene compound represented by Q(C5H4−mR1m)(C5H4−nR2n) MXY, the compound (B): an aluminoxane, the compound (C): an organoaluminum compound, and the compound (D): a particulate carrier.

Abstract: The present invention relates to a method of polymerization or co-polymerization of olefin under the catalyst system which comprises (a) a solid complex titanium catalyst comprising of a magnesium compound, a titanium compound, and an internal electron donor; (b) an organometallic compound of metal of Group I or Group III on the Periodic Table; and (c) two of external electron donors comprising an external electron donor (1) and an external electron donor (2), wherein the ratio of the MFR (1) to the MFR (2) is 2˜10, the MFR (1) being that of the homopolymer (1) obtained by using said external electron donor (1) with said solid complex titanium catalyst (a) and the organometallic compound (b), and the MFR (2) being that of the homopolymer (2) obtained by using said external electron donor (2) under the identical polymerization reaction conditions of said external electron donor (1), and wherein the NMR pentads of the homopolymer (1) and the homopolymer (2), respectively, are 95.5% or more.

Abstract: The invention is directed to olefin polymerization processes using bridged hafnocene catalyst complexes that are surprisingly stable under high temperature olefin polymerization processes such that olefin copolymers can be prepared with high molecular weights and catalyst activities. More specifically, the invention is a polymerization process for ethylene copolymers having a melt index of about 0.850 to about 0.930 comprising contacting, under homogeneous polymerization conditions at a reaction temperature at or above 60° C. to 250° C.

Abstract: A modified diene elastomer prepared by a process comprising the steps of polymerizing a diolefin compound containing a conjugated double bond in a liquid phase in the presence of a cobalt compound, an organic aluminum compound containing a halogen atom, and water, to give a solution containing a diene elastomer, and reacting the diene elastomer with an elastomer-modifying compound is favorably employed for the manufacture of tire tread, particularly when it is employed in combination with silica as a filler.

Abstract: Disclosed are a propylene polymer having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain (continuous propylene units wherein directions of &agr;-methyl carbons are the same as each other), and a process for preparing said polymer. Further disclosed is a propylene polymer composition comprising the above propylene polymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid. The propylene polymer of the invention is excellent in rigidity, heat resistance and moisture resistance, and can be favorably used for sheet, film, filament, injection molded product, blow molded product, etc.

Abstract: There are disclosed a process for producing a solid catalyst component and a catalyst for &agr;-olefin polymerization, and a process for producing an &agr;-olefin polymer, wherein the process for producing a solid catalyst component comprises the steps of:

Abstract: Disclosed are a catalyst for polymerizing olefins containing a solid catalyst component containing titanium, magnesium and halogen as essential components (component (A)); an organic aluminum compound (component (B)); and a silane compound (component (C)) represented by general formula (1) wherein R1 and R2 independently represent a straight, branched or cyclic saturated aliphatic hydrocarbon group or a silyl group, a method of preparing polyolefins using the catalyst as well as novel trimethoxysilane compounds represented by the general formula (1) in which R1 is a straight saturated aliphatic hydrocarbon group having 2 to 10 carbon atoms, and R2 represents a methyl group. Use of the catalyst enables efficient production of polyolefins having a low molecular weight (MFR>20 (g/10 minutes)), a broad molecular weight distribution (MLMFR/MFR>22) and a high stereoregularity when applied to polymerization of olefins having 3 or more carbon atoms.

Abstract: The present invention relates to mixed catalyst compositions of a Group 15 containing hafnium catalyst compound and a bulky ligand metallocene-type catalyst compound, a unsupported and supported catalyst systems thereof and to a process for polymerizing olefin(s) utilizing them.

Abstract: A novel process for producing homopolymers and copolymers of ethylene which involves contacting ethylene and/or ethylene and at least one or more other olefin(s) under polymerization conditions with a Ziegler-Natta type catalyst containing at least one or more internal electron donors, trimethylaluminum and at least one or more external electron donors containing at least one carbon-oxygen-carbon linkage (C—O—C) selected from the group consisting of Formula 1, R1—CH2—O—CH2—R2, Formula 2, Formula 3, R5—O—R6, and Formula 4, R7—O(—R8—O)n—R9. Also provided are films and articles produced therefrom.