Abstract: There is disclosed a process for producing a styrenic polymer which comprises polymerizing at least one styrenic monomer by the use of a polymerization catalyst comprising in combination (A) at least one transition metal compounds, (B) an aluminoxane, (C) a coordination complex compound comprising a cation and an anion in which a plurality of radicals are bonded to a metal and (D) an organoaluminum compound. The above process is capable of producing a styrenic polymer which has high degree of syndiotactic configuration and a wide range of molecular weight distribution and is minimized in residual metallic components at a low production cast with a high efficiency.

Abstract: Double bound metallocenes, i.e. metallocenes having a cyclopentadienyl-containing radical that is bound to a transition metal both by a pi bond and by a sigma carbon bond of a substituent of that same cyclopentadienyl-containing radical can be prepared by reducing metallocenes having a cyclopentadienyl-containing radical having at least one an unsaturated substituent. Also a process for producing polymers comprising contacting at least one olefinic monomer under suitable polymerization conditions with such double bound metallocenes.

Abstract: Provided are heterogeneous catalysts for homo- and copolymerization of olefins as well as a method for preparing these catalysts, which comprise at least one metallocene compound of a Group 4A, 5A or 6A (Hubbard) transition metal on a solid inorganic support. The mtehod comprises the steps of vaporizing the metallocene compound, treating the support material with the vaporized metallocene compound at a temperature which is sufficiently high to keep the metallocene compound in the vaporous state, contacting the support material with an amount of the vaporized metallocene compound which is sufficient to allow for a reaction between the metallocene compound and at least a substantial part of the available surface sites capable of reacting therewith, removing the rest of the metallocene compound not bound to the support, and optionally treating the product thus obtained with an activating agent. The catalysts are active even if very low amounts of activator agents, such as alumoxane, are used.

Abstract: This invention relates to a process for making a catalyst in which a metallocene is included in the synthesis of a Ziegler-Natta catalyst and a process for using the catalyst in the polymerization of olefins, specifically, propylene, to produce a polymer product with broad polydisperisty.The catalyst may be synthesized by:1) selecting a solid component comprising a magnesium dialkoxide;2) adding a chlorinating agent;3) adding a titanating agent;4) adding a metallocene prior to step 2), after step 2), prior to step 3) or after step 3) and5) adding an aluminum alkyl cocatalyst.

Abstract: Solid precursor of a catalytic system for the polymerization of olefins, containing at least one neutral halogenated metallocene derived from a transition metal, the latter being linked to at least one halogen atom, and at least one ionizing agent.Process for the preparation of this solid precursor, according to which a compound based on the neutral halogenated metallocene is mixed with a compound based on the ionizing agent in a heterogeneous medium. Catalytic system comprising an organometallic compound derived from a metal chosen from groups IA, IIA, IIB, IIIA and IVA of the Periodic Table, and a solid precursor described above. Process for the polymerization of olefins, in which this catalytic system is used.

Abstract: A novel class of olefin polymerization catalyst system based on specific organo-transition metal compounds and which are effective for controlling in particular the width and mode of the molecular weight distribution of the resulting polyolefins, and processes of olefin polymerization using the novel catalyst systems are disclosed.

Abstract: Ethylene copolymers are disclosed herein which are each derived from ethylene and an olefin of C.sub.3 to C.sub.20 and in which any quaternary carbon atom is not present in a polymeric main chain; the activation energy (Ea) of melt flow is in the range of 8 to 20 kcal/mol; and (1) a ratio between a Huggins coefficient (k.sup.1) of the copolymer and a Huggins coefficient (k.sup.2) of a straight-chain ethylene polymer having the same intrinsic viscosity meets the equation 1.12<k.sup.1 /k.sup.2 .ltoreq.5, or (2) a molar ratio ?CH.sub.3 /CH.sub.2 ! of a methyl group to a methylene group in a molecular chain is in the range of 0.005 to 0.1, and the equation Tm.gtoreq.131-1,340 ?CH.sub.3 /CH.sub.2 ! is met, or (3) Mw and a die swell ratio (DR) meet the equation DR>0.5+0.125.times.log Mw.

Abstract: Catalyst compositions comprising both metallocene complexes having polymerisable groups and polymerization catalysts eg Ziegler-Natta may be used for the preparation of polyolefins. The catalyst compositions may comprise the metallocene complex in the form of a polymer and may suitably be supported on inorganic supports. Polymers having a wide range of molecular weights and comonomer distributions may be prepared by use of the catalyst compositions. Preferred metallocene complexes are zirconium complexes in which the polymerisable group is vinyl.

Abstract: The preparation and use of organometallic complexes of Group III metals having the formula:Me(Ar)(AlX.sub.3 R).sub.3 (I)wherein Me, Ar, X and R are as defined herein, to stereospecifically polymerize unsaturated monomers is provided.

Abstract: An ethylenic polymerization catalyst comprising (A) a chromium compound, (B) a carrier, (C) aluminoxane, and (D) a transition metal compound comprising a group having conjugated .pi. electron as a ligand, wherein said chromium compound (A) is not calcined; and a process for producing an ethylenic polymer comprising a step of polymerizing a monomer comprising ethylene in the presence of the ethylenic polymerization catalyst.

Abstract: Catalyst system comprising an ionic metallocene derived from a transition metal, a catalytic solid containing an element of group IVB, magnesium and a halogen, and an aluminium derivative. Process for preparing this catalyst system, according to which a mixture of a neutral metallocene and of the catalytic solid is prepared, the mixture thus obtained is placed in contact with an aluminium derivative and an ionizing agent is added to it. Process for (co)polymerization of an olefin, according to which a mixture of the neutral metallocene and of the catalytic solid is prepared, the mixture thus obtained is placed in contact with an aluminium derivative and the olefin, and the ionizing agent is added to it.

Abstract: Disclosed are a catalyst for olefin polymerization comprising (A) a compound of a transition metal in Group IVB of the periodic table which contains a ligand having a cyclopentadienyl skeleton, (B) an organoaluminum compound and any one of (C1) a Br.o slashed.nsted acid; (C2) a material obtained by contacting (c-1) a magnesium compound with (c-2) an electron donor; and (C3) a material obtained by contacting (c-1) a magnesium compound, (c-2) an electron donor and (c-3) an organometallic compound with each other. Also disclosed are processes for polymerizing an olefin in the presence of the above-mentioned catalysts for olefin polymerization. Such catalysts and processes for olefin polymerization as described above are excellent in olefin polymerization activity and economical efficiency.

Abstract: A process for producing an alpha-olefin polymer, which comprises polymerizing an alpha-olefin in the presence of a catalyst formed from (A) a transition metal compound comprising (A-1) a transition metal atom, (A-2) a hetero atom-containing ligand containing a heteroatom selected from oxygen, sulfur, nitrogen and phosphorus capable of forming a bond with the transition metal atom, and (A-3) a ligand having a conjugated .pi. electron through which the ligand can be bonded to the transition metal atom (A-1), and (B) an aluminoxane. The transition metal compound may be pre-treated with (C) an organometallic compound, or (D) a halogen-containing inorganic compound of an element of Group III, IV or V of the periodic table.

Abstract: A process for effectively producing a cyclic olefin polymer and a cyclic olefin/alpha-olefin copolymer without opening the cyclic olefin, is disclosed. Further, a novel cyclic olefin/alpha-olefin copolymer prepared by the above-mentioned process, compositions and molded articles comprising the novel copolymer, are also disclosed. In the process for producing a cylcic olefin based polymer according to the present invention, homopolymerization of a cyclic olefin or copolymerization of a cyclic olefin and an alpha-olefin is effected in the presence of a catalyst comprising, as main ingredients, the following Compounds (A) and (B), and optionally Compound (C):(A) a transition metal compound;(B) a compound capable of forming an ionic complex when reacted with a transition metal compound; and(C) an organoaluminum compound.

Abstract: There are disclosed a catalyst for producing an aromatic vinyl compound-based polymer composition which catalyst comprises (A) at least two different transition metal compounds each having one .pi.-ligand and (B) an ionic compound comprising a noncoordinate anion and a cation and/or an aluminoxane, and (C) a Lewis acid to be used as the case may be; and a process for producing an aromatic vinyl compound-based polymer composition having a high degree of syndiotactic configuration in its aromatic vinyl chains which process comprises polymerizing an (a) aromatic vinyl compound and (b) an olefinic compound and/or a diolefinic compound in the presence of the above catalyst.

Abstract: Olefin polymerization catalysts the procatalyst component of which comprises a transition-metal compound on a magnesium chloride support material are known to all. Now the procatalyst component has been improved by incorporating a manganese (II) halide into it at a rate of at minimum approx. 0.1% and at maximum approx. 50% of the total molar amount of magnesium chloride and manganese (II) halide. The new polymerization catalyst has, among other things, the excellent special property that it yields a polyolefin with a broad molecular weight distribution.

Abstract: The present invention is a process for producing a polymer blend in a single reactor, specifically a polymer blend of isotactic polyolefins and syndiotactic polyolefins. The catalyst system is a combination of at least one metallocene catalyst and at least one conventional supported Ziegler-Natta catalyst. The multi-catalyst system is obtained by mixing the components of at least one metallocene catalyst and at least one conventional supported Ziegler-Natta catalyst. The metallocene catalyst comprises a metallocene compound and an ionizing agent. The conventional supported Ziegler-Natta catalyst comprises an aluminum alkyl and a transition metal compound with, optionally, an electron donor.

Abstract: Olefin is polymerized using a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being prepared by reacting 1 a reaction product obtained by reacting the reaction product of Si oxide and/or Al oxide and Ti compound or both Ti compound and V compound (Ti.V component) with organic Al compound, with 2 a reaction product obtained by the reaction of Mg halide, a compound of the general formula Me(OR).sub.n X.sub.z-n and Ti.V component (optional component), and further reacting the reaction product of the above 1 and 2 with 3 a compound of the general formula R.sub.p Si(OR).sub.q X.sub.4-p-q.

Abstract: The present invention is a process for producing a catalyst system to produce polymer blends in a single reactor, polymer blends of isotactic polyolefins and syndiotactic polyolefins. The catalyst system is a combination of at least one metallocene catalyst and at least one conventional supported Ziegler-Natta catalyst. The multi-catalyst system is obtained by mixing the components of at least one metallocene catalyst and at least one conventional supported Ziegler-Natta catalyst. The metallocene catalyst comprises a metallocene compound and an ionizing agent. The conventional supported Ziegler-Natta catalyst comprises an aluminum alkyl and a transition metal compound with, optionally, an electron donor.

Abstract: Catalytic solid for the (co)polymerisation of at least one olefin, comprising a coprecipitate of magnesium and of at least one transition metal, obtained by means of a process comprising the preparation of a mixture of a magnesium compound, such as the chloride or a magnesium alcoholate, and of a compound denoted by one of the formulae MY.sub.x (O--R').sub.t-x and M'O.sub.y (O--R").sub.s-2y and the treatment of the resulting mixture with a complex of formula M"(A)Al.sub.2 (X',X").sub.8 where X' and X" denote halogens, M and M' transition metals of groups IVB and VB, M" a transition metal of group IVB, A an aromatic hydrocarbon, Y a halogen or a group (O--R'"), and R', R" and R'" an alkyl, aryl or cycloalkyl group.

Abstract: A method for producing a polyolefin in the presence of a catalyst comprising a transition metal compound and an organometallic compound, wherein a catalyst system is used which comprises: (A) a solid catalyst component prepared by reacting a uniform solution containing (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) an electron donative compound and (III) an oxygen-containing organic compound of titanium, with (IV) at least one aluminum halide compound to obtain a solid product, adding to this solid product (V) at least one compound selected from the group consisting of oxygen-containing organic compounds of one or more transition metals of Group IVa of the Periodic Table, and then treating the mixture with (VI) an aluminum halide compound, and (B) at least one catalyst component selected from the group consisting of organoaluminum compounds.

Abstract: Disclosed in an olefin polymerization catalyst comprising a transition metal compound having at least two transition metals in which at least one of said metals is bonded to a ligand having a cyclopentadienyl skeleton, at least one of said metals is selected from Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and lanthanoid metals and at least on of the others is selected from the specific transition metals; and an organoaluminum oxy-compound or an organoboron compound. Corresponding to the kind of the metal combined with said metal selected from Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and lanthanoid metals, the olefin polymerization catalyst exhibit a property to give polymers having a wide molecular weight distribution in spite of the catalyst system using one kind of a transition metal compound, or to give polymers having high molecular weight and be excellent in the polymerization activity at low polymerization temperature.

Abstract: A composition, which can be used as catalyst for producing an olefin polymer having a multimodal molecular weight distribution, is provided that comprises a transition metal-containing catalyst, a metallocene, and a boron-containing organoaluminoxane, wherein each component of the composition is present in an effective amount so that an olefin polymer having a multimodal molecular weight distribution can be produced using the composition as catalyst, preferably in the presence of a cocatalyst. Also provided is a process for preparing the composition which comprises: (1) contacting a transition metal-containing catalyst with an organoaluminoxane dispersed in a solvent to form a slurry; (2) combining the slurry with a boroxine to prepare a combination of a transition metal-containing catalyst and boron-containing organoaluminoxane; and (3) contacting the combination with a metallocene. Further provided is a process for polymerizing an olefin to prepare an olefin polymer using the composition.

Abstract: Disclosed is a novel transition metal compound represented by the following formula: ##STR1## wherein M is a transition metal, X is halogen or the like, R.sup.1 is a hydrocarbon group or the like, R.sup.2 is an aryl group substituted with a halogenated hydrocarbon group, and Y is a divalent silicon-containing group or the like.Also disclosed are an olefin polymerization catalyst component comprising the transition metal compound, an olefin polymerization catalyst comprising the olefin polymerization catalyst component, and a process for olefin polymerization using the olefin polymerization catalyst.An olefin polymerization catalyst component having high polymerization activity can be formed from the transition metal compound. By the use of the olefin polymerization catalyst or the process for olefin polymerization, polyolefins having a high melting point and a high molecular weight can be prepared with high polymerization activity.

Abstract: A support containing methylalumoxane and derivatives thereof is described which is formed by an incipient impregnation technique. The most preferred support is silica. Incipient impregnation in accordance with the invention provides a supported alumoxane, methylalumoxane, which substantially eliminates the problem of fluidized bed reactor fouling when methylalumoxane is introduced into the reactor during its operation. In accordance with the invention, the process comprises providing methylalumoxane activated metallocene compound in particulate form as catalysts in fluidized bed gas phase operation.

Abstract: There is disclosed a process for producing a styrenic polymer, especially, syndiotactic polystyrene, which comprises polymerizing a styrenic monomer by the use of a (a) transition metal compound, a (b) coordination complex compound comprising an anion in which a plurality of racicals are bonded to a metal and a cation or a Lewis acid, a (c) alkylating agent (alkyl group-containing aluminum, magnesium or zinc compound) and a (d) reaction product between a straight-chain alkylaluminum having at least two carbon atoms and water (alkylaluminoxane). The above process is capable of simplifying the production process and producing high-performance styrenic polymer having a high degree of syndiotactic configuration in high catalytic activity without deteriorating the catalyst activity, increasing the amounts of residual metals in the objective polymer or leaving the decomposition products of the alkylaluminum therein, thereby curtailing the production cost of the objective polymer.

Abstract: There are disclosed a transition metal compound of the general formula RMX.sub.a-1 L.sub.b (R is as a .pi. ligand, a fused polycyclic cyclopentadienyl group in which at least one of many-membered rings to which cyclopentadienyl groups are fusedly bonded is a saturated ring, M is a transition metal, X is a .sigma. ligand, L is a Lewis base, a is the valency of M, and b is 0, 1 or 2); a polymerization catalyst for styrene, etc. comprising the above transition metal, preferably further comprising an oxygen atom containing compound ionic compound or organoboron compound and optionally a Lewis base; and a process for producing a polymer of a compound containing an ethylenically unsaturated double bond or an acetylenic polymer, especially a syndiotactic polystyrene by using the above polymerization catalyst. The catalyst is particularly effectivive for producing highly syndiotactic polystyrene minimized in residual metals amounts at a low cost in enhanced efficiency.

Abstract: Disclosed is a catalyst system for the homopolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a mixed-valent dimeric Group 6b metal compound catalyst precursor wherein one atom of said Group 6b metal is a cyclopentadienyl Group 6b metal hydrocarbyl complex in which the Group 6b metal has an oxidation state +3 and wherein one atom of said Group 6b metal is a cyclopentadienyl alkaryl complex in which the Group 6b metal has an oxidation state +1, said dimeric Group 6b metal compound being supported on an inorganic support. The catalyst system can contain, in addition, a Group 2 or Group 3 metal-alkyl compound.

Abstract: A catalyst system comprising a bridged fluorenyl-containing metallocene, an unbridged metallocene, and a suitable cocatalyst and the use of such catalyst systems to produce olefin polymers. Also novel olefin polymers produced by those processes.

Abstract: The invention disclosed herein includes a process for producing highly amorphous polypropylene and a highly amorphous polypropylene produced by this process comprising contacting propylene with (1) a catalyst comprising a titanium compound supported on a rare earth halide and (2) a metal alkyl cocatalyst wherein the metal is selected from the group consisting of groups II and III of the Periodic Table under conditions for producing a highly stereo- and regio-irregular amorphous propylene polymer.

Abstract: A catalytic component having controlled structure for use in combination with a cocatalyst for the polymerization of ethylene, and being the product of the process of subjecting a component consisting essentially of titanium, magnesium, and chlorine to a reduction treatment and after such treatment contacting the component with a transition metal chlorine-containing compound and process of polymerizing ethylene using such catalytic component to produce polymers having a broad molecular weight distribution.

Abstract: Resins which are in situ catalytically produced blends of broad bimodal molecular weight distribution ethylene resin are produced. The resins of the invention are characterized by a blend of low molecular weight component and high molecular weight component with HMW component weight fraction which is greater than 0 (zero). Generally, the LMW/HMW weight fraction can be controlled within a very broad range. The resin has a molecular weight distribution, which is characterized as MFR or Mw/Mn. The bimodal molecular weight resins can be processed into films on existing equipment, and exhibit good processability in blown film production and provide film product of excellent FQR. The resin of the invention exhibits reduced tendency towards die-lip buildup and smoking in on-line operations.

Abstract: A bimetallic catalyst produces broad or bimodal molecular weight distribution polyolefin resin whose composition depends on the ratio of the concentration of the two metals of the catalyst producing the HMW and LMW components. The bimetallic catalyst produces a broad/bimodal MWD resin whose HMW and LMW components depend on the relative productivity of each of the transition metal sites of the catalyst. Water and/or carbon dioxide are cofed to the polymerization reactor at levels necessary to modify the weight fractions of the HMW and LMW components, thus achieving a target molecular weight distribution, MWD. The invention allows the resin MWD to be adjusted in the reactor. The weight fraction of the high molecular weight component decreases with the addition of the water and or the carbon dioxide and the FI of the overall product increases with a decrease in the HMW component weight fraction in the product.

Abstract: There are disclosed a catalyst for producing an aromatic vinyl compound polymer which catalyst comprises a contact product between an (A) trivalent titanium compound and a (B) compound represented by the general formula (II) or (III)R.sup.1.sub.k M.sup.1 L.sup.2.sub.m (II)R.sup.1.sub.k M.sup.1 X.sup.2.sub.l L.sup.2.sub.m (III)a (C) an ionic compound comprising a noncoordinate anion and a cation, an aluminoxane or an organoboron compound; and optionally a (D) Lewis acid, and a process for producing an aromatic vinyl compound polymer having a high degree of syndiotactic configuration which process comprises polymerizing (a) an aromatic vinyl compound or (b) an aromatic vinyl compound together with an olefin or a diolefin in the presence of the above catalyst.

Abstract: Polyolefins having better particle properties are obtained by polymerizing olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, the said solid catalyst component being prepared by reacting the following components [I] and [II] and further reacting the resulting reaction product with the following component [III]:[I] a reaction product obtained by reacting:(1) a silicon oxide and/or an aluminum oxide, and(2) a titanium compound, or a titanium compound and a vanadium compound, and further reacting the resulting reaction product with:(3) an organoaluminum compound;[II] a reaction product obtained by the reaction of:(1) a magnesium halide, and(2) a compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.

Abstract: The subject invention relates to a technique for synthesizing rubbery non-tapered, random, copolymers of 1,3-butadiene and isoprene. These rubbery copolymers exhibit an excellent combination of properties for utilization in tire sidewall rubber compounds for truck tires. By utilizing these isoprene-butadiene rubbers in tire sidewalls, tires having improved cut growth resistance can be built without sacrificing rolling resistance. Such rubbers can also be employed in tire tread compounds to improve tread wear characteristics and decrease rolling resistance without sacrificing traction characteristics.

Abstract: A process for the preparation of an ethylenic polymer composition having excellent physical properties such as high impact properties, environmental stress cracking resistance, pinch-off fusing characteristics and having an intrinsic viscosity ranging from 3.2 to 4.5 dl/g and a density ranging from 0.943 g/cm.sup.3 to 0.958 g/cm.sup.3.

Abstract: A transition metal containing catalyst useful for the polymerization of .alpha.-olefins is prepared by (A) forming in an inert atmosphere which excludes oxygen and moisture a slurry of (1) a porous inorganic oxide support material selected from the group consisting of silica, alumina, or a combination of silica and alumina, said support material containing not greater than about 5 millimoles of hydroxyl groups per gram of support material and a particle size not greater than about 10 microns and a surface area of from about 50 to about 800 m.sup.2 /g in an inert organic liquid medium; (B) mixing said slurry with (2) an alkoxide and stirring the resultant mixture at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to saturate the surface of the support material; (C) mixing the product form (B) with (3) a titanium compound or a combination of a titanium compound and (4) a vanadium compound and stirring the resultant mixture at a temperature of from about -20.degree. C.

Abstract: A process for the polymerization of ethylene or the copolymerization of ethylene with an alpha-olefin, in suspension or in gas phase, in the presence of a catalyst consisting essentially of a cocatalyst and a catalytic component based on at least Mg, Ti and Cl, with the catalytic component being constituted of at least one derivative of magnesium and one chlorinated derivative of titanium in its form III and/or IV, which was subjected, prior to its use, to a reduction treatment and then to treatment with a chlorinated transition metal compound, with the said catalytic component being characterized in that the magnesium derivative is in the form MgCl.sub.2.MgO.

Abstract: A support containing methylalumoxane and derivatives thereof is described which is formed by an incipient impregnation technique. The most preferred support is silica. Incipient impregnation in accordance with the invention provides a supported alumoxane, methylalumoxane, which substantially eliminates the problem of fluid bed reactor fouling when methylalumoxane is introduced into the reactor during its operation. The process comprises providing methylaluminoxane in particulate form for use as a catalytic component in the fluidized bed gas phase polymerization process.In accordance with the invention, the process comprises providing methylalumoxane activated metallocene compound in particulate form as catalysts in fluid bed gas phase.

Abstract: Ethylene is homopolymerized in the presence of a catalyst consisting essentially of a Group 3 metal complex, preferably a scandium complex, having a bridged ligand structure. Optionally polymer blends are prepared by combining the process with another polymerization process, either in series or in parallel.

Abstract: A catalyst system for the polymerization of alpha-olefins comprising a chromium-containing catalyst and an yttrium-containing catalyst wherein the yttrium-containing catalyst is represented by the formula (Cp.sub.2 YX.sub.x).sub.y .multidot.M.sub.z L.sub.n, wherein Cp is cyclopentadienyl or cyclopentadienyl substituted with an alkyl or alkyl silyl radical, X is a halogen, M is an alkali metal, L is a suitable electron donor ligand, x is 1 or 2, y is 1 or 2, z is 0 or 1, and n is a number corresponding to the value needed to form a stable complex, with the proviso that when y is 2, z and n are 0 is provided. Also disclosed is a polymerization process employing such a catalyst system, and novel olefin polymers. Polymers thus produced exhibit high bulk density and a broad molecular weight distribution.

Abstract: The present invention relates to a solid catalyst composed of a specific solid catalyst component [A-1], the catalyst containing the solid catalyst and the olefin polymerization process using the solid catalyst, in which the solid catalyst component [A-1] comprises; (a-1) a particulate carrier composed of a specific oxide of a metal; (a-2) an organoaluminum oxy compound; and (a-3) a specific transition metal compound containing a specific ligand, wherein the organoaluminum oxy compound (a-2) and the transition metal compound (a-3) are supported on the particulate carrier (a-1).The catalysts are applicable to a suspension polymerization and a vapor phase polymerization, and capable of preparing spherical olefin polymers excellent in particle characteristics at high polymerization activity.

Abstract: A process for preparing syndiotactic vinylidene aromatic polymers comprising contacting one or more vinylidene aromatic monomers with a catalyst comprising a cationic Group 4 metal complex wherein the metal is in the +3 oxidation state formed from the corresponding metal hydrocarbyloxy containing complex in the presence of a hydrocarbylation agent.

Abstract: Novel chromium-containing compounds are prepared by forming a mixture of a chromium salt, a metal amide, and an ether. These novel chromium-containing, or chromium pyrrolide, compounds, with a metal alkyl and an unsaturated hydrocarbon, can be used as a cocatalyst system in the presence of an olefin polymerization catalyst system to produce a comonomer in-situ. The resultant polymer, although produced from predominately one monomer, has characteristics of a copolymer.

Abstract: Disclosed is a method of making polyethylene wherein ethylene, a catalyst, a cocatalyst and a solvent are added to a reactor. A first mixture is formed of the ethylene and either the catalyst or the cocatalyst and a second mixture is separately formed of the solvent and the other of the catalyst or cocatalyst. These two mixtures are then combined in a reactor to produce the polyethylene.

Abstract: A novel transition metal compound represented by the formula ##STR1## (wherein each of A.sup.1, A.sup.2, A.sup.3 and A.sup.4 is a cyclopentadienyl group, an indenyl group, a fluorenyl group or their derivative; A.sup.5 is a hydrocarbondiylidene group having 4 to 30 carbon atoms; a pair of A.sup.1 and A.sup.2 as well as a pair of A.sup.3 and A.sup.4 is respectively bonded to the identical carbon atom in A.sup.5 to form a crosslinking structure; each of R.sup.1 and R.sup.2 is a halogen atom, a hydrogen atom, an alkyl group or a silicon-containing alkyl group having 1 to 10 carbon atoms, an aryl group, an alkylaryl group, an arylalkyl group or a halogenated aryl group having 6 to 20 carbon atoms; R.sup.1 and R.sup.2 may be identical or different; each of M.sup.1 and M.sup.2 is titanium, zirconium or hafnium; and M.sup.1 and M.sup.2 may be mutually identical or different), and a method for polymerizing an olefin in the presence of this compound and a co-catalyst.

Abstract: A polymerization catalyst system is provided comprising a catalyst and a cocatalyst, wherein the catalyst comprises a chromium compound and a transition metal compound, wherein said chromium compound is a cyclopentadienyl compound, wherein the transition metal compound is a titanium hydrocarbyloxide, and wherein said cocatalyst is an organoaluminum-halide compound. Other aspects of the invention provide a process for preparing the catalyst described above, a polymerization process employing the catalyst, and the polymer produced.

Abstract: A catalyst system for the polymerization of alpha-olefins comprising a chromium-containing catalyst and an yttrium-containing catalyst wherein the yttrium-containing catalyst is represented by the formula (Cp.sub.2 YX.sub.x).sub.y.M.sub.z L.sub.n, wherein Cp is cyclopentadienyl or cyclopentadienyl substituted with alkyl or alkyl silyl radical or radicals, X is a halogen, M is an alkali metal, L is a suitable electron donor ligand, x is 1 or 2, y is 1 or 2, z is 0 or 1, and n is a number corresponding to the value needed to form a stable complex, with the proviso that when y is 2, z and n are 0 is provided. Also disclosed is a polymerization process employing such a catalyst system, and novel olefin polymers. Polymers thus produced exhibit high bulk density and a broad molecular weight distribution.

Abstract: Disclosed is a catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b metal compound having at least one oxo, thio, imido or phosphido group bonded directly to the Group 6b metal, and at least one organic radical bonded to the Group 6b metal through a carbon atom, said Group 6b metal compound being supported on an inorganic support. The catalyst system may also contain a Group 2 or Group 3 metal alkyl compound cocatalyst.