Abstract: Disclosed is a method for the oligomerization of olefins, wherein an olefin is brought into contact with a catalyst system that is obtained from a chromium source, a cycloalkylalkyl-substituted triazacyclohexane, especially a 1,3,5-tris-(cycloalkylalkyl)-1,3,5-triazacyclohexane and an activator such as an alkyl aluminum compound or an alkylalumoxane.

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: 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: A catalyst composition for use in dimerizing, co-dimerizing or oligomerizing olefins results from dissolving a nickel compound, optionally mixed or complexed with a ligand, in a medium resulting from mixing: at least one quaternary ammonium halide and/or at least one quaternary phosphonium halide; at least one aluminum halide; and at least one aluminoxane.

Abstract: A catalyst composition for preparing olefin polymers. The catalyst composition includes a metallocene compound and an activating cocatalyst. In the metallocene compound, two cyclopentadienyl groups are bridged by X (carbon) in a ring structure and the bridge X forms a three-, four-, or five-member ring structure. The bite angle ? formed by the two cyclopentadienyl rings and X is equal to or greater than 100 degrees. The obtained olefin polymer has high cycloolefin conversion and a high glass transition temperature. In addition, the catalyst composition can still maintain relatively high activity at high temperature reaction conditions. The metallocene compound is represented by formula (I) below.

Abstract: The present invention provides a novel process for the preparation of isoolefin copolymers in the presence of zirconium halides or hafnium halides or mixtures thereof and organic nitro compounds, especially for the preparation of butyl rubbers, as well as isoolefin copolymers composed of isobutene, isoprene and, optionally, further monomers.

Abstract: A novel olefin polymerization catalyst comprising: (A) a transition metal compound comprising a transition metal having &eegr;-bonded thereto a cyclic anionic ligand; (B) a mixture of (B-1) an activator compound capable of forming, together with component (A), a metal complex having a catalytic activity and (B-2) an organometal compound, the activator compound (B-1) comprising a cation and a noncoordinating, compatible anion; (C) a solid component; and optionally (D) an organoaluminum compound, wherein the catalyst is obtained by contacting components (A) to (C) and optionally component (D).

Abstract: The invention relates to a process for the in-situ preparation of alkylated single-site transition metal catalysts by contacting a precatalyst with an alkylating agent in the presence of one or more olefin monomers in the polymerization system. The precatalyst, which is produced prior to introducing into the polymerization system, is obtained by contacting a transition metal complex and boron-containing ionizing agent, optionally, with a support.

Abstract: A process for the preparation of a supported catalyst system, an inorganic carrier material being reacted with a metal compound of the formula M1(R1)r(R2)5(R3)t(R4)u  I in the presence of an inert solvent in a first step and, in a subsequent step, the suspension thus obtained being reacted with a metallocene complex and a compound forming metallocenium ions, in which process the solvent is not removed after the first step and the subsequent step is carried out without isolation of the pretreated carrier material thus obtained.

Abstract: A oxygen reduction catalyst includes a coordination complex of a transition metal and a nitrogen-carbon ligand. The catalyst may be formed by preparing a sol-gel with a metal salt such as a cobalt salt in an alcohol and adding the ligand slowly while refluxing. The catalyst may be adsorbed onto carbon powder and heat treated.

Abstract: The present invention provides a novel process for the preparation of isoolefin copolymers in the presence of zirconium halides or hafnium halides or mixtures thereof and organic nitro compounds, especially for the preparation of butyl rubbers, as well as isoolefin copolymers composed of isobutene, isoprene and, optionally, further monomers.

Abstract: The present invention relates to catalyst components for the polymerization of olefins, and to the catalyst obtained therefrom, particularly suitable for the stereospecific polymerization of olefins, comprising Ti, Mg, halogen and an electron donor compound selected from heteroatom containing esters of malonic acids (hereroatom containing malonates). Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: The present invention provides a Ziegler-Natta catalyst useful in solution processes for the polymerization of olefins having a low amount of aluminum and magnesium. The catalysts of the present invention contain an alkyl silanol and have a molar ratio of Si:Ti from 0.25:1 to 4:1. The catalysts are effective for the solution polymerization of olefins at high temperatures.

Abstract: A catalytic composition for the dimerization, the codimerization or the oligomerization of olefins results from the dissolution of at least one nickel complex that contains a heterocyclic carbene in a liquid mixture that comprises at least one ammonium halide or quaternary phosphonium halide, at least one aluminum halide and optionally at least one organometallic aluminum compound. It is used in a process of dimerization, codimerization or oligomerization of olefins.

Abstract: The present invention provides a novel process for the preparation of isoolefin copolymers in the presence of zirconium halides or hafnium halides or mixtures thereof and organic nitro compounds, especially for the preparation of butyl rubbers, as well as isoolefin copolymers composed of isobutene, isoprene and, optionally, further monomers.

Abstract: Catalyst-forming components and catalysts for the polymerization of olefins based on said components are disclosed. The catalysts comprise the reaction product of: (a) an Al alkyl compound; (b) a silicon compound containing at least a Si—OR or Si—OCOR or Si—NR2 bond, R being a hydrocarbyl radical; and (c) a solid comprising, as essential support, a Mg dihalide in active form and, supported thereon, a Ti halide or a halo-Ti-alcoholate or said halogenated Ti compound and a silicon compound as defined in (b) in a molar ratio with the supported Ti compound from 1.0 mole to 5 moles of silicon compound per mole of Ti compound. The present invention refers to new supported components of catalysts for the polymerization of CH2═CHR olefins wherein R is an alkyl radical with 1 to 4 carbon atoms, or an aryl radical, and mixtures of said olefins with ethylene, and to the catalysts obtained from said components.

Abstract: The present invention relates to a novel encapsulated organometallic cluster complex catalyst and to a process for the preparation thereof. The oxo-bridged organometallic cluster complex of the invention has at least one atom of cobalt and manganese encapsulated in micro and mesoporous porous solids like aluminosilicate zeolites, aluminophosphates, carbon molecular sieves, silica and is particularly effective for oxidation of aromatic alkyl groups to the carboxyl groups in high yields.

Abstract: Supported catalysts for the polymerization of olefins comprise the following components: (A) a porous organic support functionalised with groups having active hydrogen atoms; (B) an organo-metallic compound of aluminium containing heteroatoms selected from oxygen, nitrogen and sulphur; and (C) a compound of a transition metal selected from those of groups IVb, Vb or VIb of the Periodic Table of the Elements, containing ligands of the cyclopentadienyl type. These supported catalysts, obtainable in the form of spherical particles, can be used in the polymerization reaction of olefins either in liquid or in gas phase, thus producing polymers endowed with a controlled morphology and with a high bulk density.

Abstract: Unsaturated nitrogenous compounds are used as electron donors in conjunction with catalytic polymerization of addition polymerizable monomers such as olefins, using supported Ziegler-Natta catalysts. The electron donors may be used in the preparation of catalyst systems, thus serving as “internal” electron donors, or they may be added during or just prior to polymerization, as an “external” electron donor.

Abstract: Supported catalysts for the polymerization of olefins comprise the following components: (A) a porous organic support functionalised with groups having active hydrogen atoms; (B) an organo-metallic compound of aluminium containing heteroatoms selected from oxygen, nitrogen and sulphur; and (C) a compound of a transition metal selected from those of groups IVb, Vb or VIb of the Periodic Table of the Elements, containing ligands of the cyclopentadienyl type. These supported catalysts, obtainable in the form of spherical particles, can be used in the polymerization reaction of olefins either in liquid or in gas phase, thus producing polymers endowed with a controlled morphology and with a high bulk density.

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: A catalyst system comprising a Group 4 transition metal cation having bonded thereto (1) a single cyclopentadienyl ligand or polycyclic derivative thereof, (2) a Group 15 or 16 heteroatom ligand, said single cyclopentadienyl ligand or polycyclic derivative and said heteroatom ligand being covalently bound and bridged to each other, and (3) at least one other ligand selected from the group consisting of hydride, hydrocarbyl, substituted hydrocarbyl, and hydrocarbyl substituted organonometalloid radicals; (b) a compatible non-coordinating anion; (c) a Group 13 element, hydrolyzable Lewis acid compound. The catalyst system is useful for polymerizing olefins, diolefins, cyclic olefins or acetylenically unsaturated monomers, either alone or in combination with each other or with other polymerizable monomers.

Abstract: Hydroxyaromatic compounds such as phenol are carbonylated with oxygen and carbon monoxide in the presence of a catalyst system comprising a metal from Groups 8-10 of the Periodic Table having an atomic number of at least 44, preferably palladium; an alkali metal or alkaline earth metal halide, preferably sodium bromide; at least one carboxylic acid amide such as N-methylpyrrolidone or dimethylacetamide; and a cocatalyst which is a compound of one or more metals including copper, titanium, zinc, lead, cerium and manganese.

Abstract: A catalyst which is useful in slurry or gas phase olefin polymerizations and which is prepared by depositing a combination of an organometallic complex of a group 4 metal and a so-called ionic activator on a metal oxide support. The organometallic complex is characterized by being unbridged and by having a cyclopentadienyl ligand, a phosphinimine ligand and an activatable ligand. The “ionic activator” (for example, triphenylcarbenium tetrakis (pentafluorophenyl) boron) is co-deposited with the organometallic complex. The metal oxide support is pre-treated with, for example, an aluminum alkyl in an amount which is at least equivalent to the molar concentration of surface hydroxyls on the support.

Abstract: The invention relates to a process for the in-situ preparation of alkylated single-site transition metal catalysts by contacting a precatalyst which comprises halogen, alkoxy or amido group, with an alkylating agent in the polymerization system. The precatalyst, which is produced prior to introducing into the polymerization system, is obtained by contacting a transition metal complex and boron-containing ionizing agent, optionally, with a support.

Abstract: This invention relates to supported and nonsupported catalyst components comprising (a) an ionic compound comprising (a)(1) a cation and (a)(2) an anion having up to 100 nonhydrogen atoms and the anion containing at least one subtituent comprising a moiety having an active hydrogen reacted with (c) an organometal or metalloid compound wherein the metal or metalloid is selected from Groups 2, 12, 13, or 14 of the Periodic Table of the Elements, and, optionally, (b) a transition metal compound, (d) a support material, and/or a diluent. Included are methods for preparation of the catalyst components, catalysts, reaction products and dispersions thereof, as well as polymerization process using the catalyst.

Abstract: A polyolefin elastomer possessing a unique combination of properties, i.e., high molecular weight (Mw), high Mooney viscosity (ML1+4 at 125° C.), low polydispersity index (Mw/Mn) and low glass transition temperature (Tg), is obtained by a polymerization process employing a particular type of a metallocene catalyst. The polyolefin elastomer is useful for manufacturing a variety of products including rubber articles such as hoses, belts and moldings, polymer blends containing one or more other hydrocarbon polymers and lubricating oils in which the elastomer functions as a viscosity modifier. Also disclosed is a cocatalyst for activating the metallocene procatalyst employing a specific molar ratio of the components of the cocatalyst to the transition metal of the procatalyst.

Abstract: A catalyst for the polymerization of vinylaromatic monomers, and particularly styrene, with a high yield and a high syndiotacticity index, comprises the product consisting of the following two components in contact with each other: A) an &eegr;5-cyclopentadienyl complex of titanium; B) an organo-oxygenated compound of aluminum; and contains a sufficient amount of at least one carboxylated product having the following general formula: R—COO—G  (I) wherein R—COO is a carboxylic group comprising the organic radical R having from 1 to 30 carbon atoms, and G represents a hydrogen atom, an aliphatic or aromatic hydrocarbon group having from 1 to 20 carbon atoms or a metal atom, possibly substituted, linked to said carboxylic group.

Abstract: The present invention relates to a process for preparing a metallocene catalyst system, which comprises reacting a metallocene starting compound in a solvent with a compound capable of transferring hydrocarbon radicals and converting the resulting metallocene compound which is &sgr;-substituted by one or more hydrocarbon radicals in solution without isolation into a polymerization-active catalyst system by means of an activator.

Abstract: A method for preparing a silica supported, &agr;-olefin polymerization catalyst includes the steps of treating a silica support with an organosilane compound, contacting the silylated silica support with a transition metal compound to form an intermediate, then contacting the resulting intermediate with an alkylmagnesium alkoxide to form the catalyst. The transition metal compound is either a metal chloride or a metal chloroalkoxide, and the transition metal is selected from titanium, vanadium, and zirconium. The alkylmagnesium alkoxide may be selected from butylethylmagnesium butoxide, butylethylmagnesium 2-ethylhexoxide, butyloctylmagnesium ethoxide, or butylmagnesium propoxide. The process steps may be carried out in the presence of an aliphatic organic solvent, such as heptane, with a slurry of solids in the solvent being formed during the process steps.

Abstract: The invention relates to solid catalyst components for the polymerization of olefins CH.sub.2 .dbd.CHR, in which R is hydrogen or a hydrocarbyl radical with 1-12 carbon atoms, comprising Ti, Mg, halogen and an electron donor compound selected from cyanoesters of formula (1): ##STR1## wherein R.sub.1 is a C.sub.1 -C.sub.20 linear or branched alkyl, alkenyl, cycloalkyl, cycloalkylalkyl, alkylcycloalkyl, aryl, arylalkyl or alkylaryl group; n is 0, 1, 2 or 3; R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are independently selected from hydrogen or C.sub.1 -C.sub.20 linear or branched alkyl, alkenyl, cycloalkyl, cycloalkylalkyl, alkylcycloalkyl, aryl, arylalkyl or alkylaryl groups; two or more of R.sub.2 and R.sub.3, and R.sub.4 and R.sub.5, can be joined to form a cycle. Said catalyst components when used in the polymerization of olefins are characterized by an excellent response to hydrogen and capability to produce polymers with broad Molecular Weight Distribution.

Abstract: This invention is generally directed toward a supported catalyst system useful for polymerizing olefins. The method for supporting the catalyst of the invention provides for a supported metallocene catalyst which when utilized in a polymerization process substantially reduces reactor fouling and sheeting in a gas or slurry polymerization process.

Abstract: A catalyst comprising a cocatalyst and a catalyst component obtained by contacting a silicon-containing metallocene compound with an inorganic support to chemically bond the metallocene compound to the inorganic support, wherein the silicon-containing metallocene compound has a formula (I): ##STR1## wherein: M is a metal selected from [the group consisting of] group 4, 5, or 6 of the periodic table;each X is independently selected from the group consisting of hydrogen, halogen, C.sub.1 -C.sub.10 alkyl, C.sub.1 -C.sub.10 alkoxy, C.sub.6 -C.sub.10 aryl, C.sub.6 -C.sub.10 aryloxy, C.sub.2 -C.sub.10 alkenyl, C.sub.7 -C.sub.40 arylalkyl, C.sub.7 -C.sub.40 alkylaryl, and C.sub.8 -C.sub.40 arylalkenyl;A.sub.1 and A.sub.2 are independently selected from the group consisting of cyclopentadienyl, substituted cyclopentadienyl, indenyl, fluorenyl, substituted indenyl, and substituted fluorenyl, wherein the substituents are independently C.sub.1 -C.sub.10 linear or branched alkyl, C.sub.5 -C.sub.

Abstract: An aminosilane of the formula: ##STR1## where R.sub.1 is a linear or branched C.sub.1-22 alkyl or C.sub.3-22 cycloalkyl, which may be substituted with at least one halogen atom; R.sub.2 is a bis(linear or branched C.sub.1-22 alkyl or C.sub.3-22 cycloalkyl)amino, a substituted piperidinyl, a substituted pyrrolidinyl, decahydroquinolinyl, 1,2,3,4-tetrahydroquinolinyl or 1,2,3,4-tetrahydroisoquinolinyl, with the substituent selected from the group consisting of C.sub.1-8 alkyl, pheny. C.sub.1-8 linear or branched alkylsubstituted phenyl and trimethylsilyl, with the proviso that when the substituent is C.sub.1-8 alkyl, there must be at least two such substituent groups present and R.sub.1 must contain halogen; and R.sub.3 is a linear or branched C.sub.1-8 alkyl or C.sub.3-8 cycloalkyl.

Abstract: This invention is generally directed toward a supported catalyst system useful for polymerizing olefins. The method for supporting the catalyst of the invention provides for a supported bulky ligand transition metal catalyst which when utilized in a polymerization process substantially reduces the reactor fouling and sheeting in a gas, slurry or liquid pool polymerization process.

Abstract: A heterogeneous catalyst system comprising a novel titanium catalyst component, the product of a sequential reaction of titanium halide with carbodiimide compound and an organometallic aluminum compound, supported on such an inorganic carrier as magnesium halide and an organometallic aluminum cocatalyst component which is not methylaluminoxane, and a process for polymerization of olefin using the said catalyst system. The catalyst system has an excellent (co)polymerization properties and produces copolymers having a narrow compositional distribution, a broad molecular weight distribution and excellent morphological properties such as spherical shape and a high bulk density.

Abstract: Catalyst compositions that are highly tolerant of catalyst poisons comprising a cationic or zwitterionic Group 4 metal complex of the constrained geometry type and an organoaluminum hydrocarbyloxide compound according to the formula R.sup.1.sub.2 Al(OR.sup.2),wherein R.sup.1 and R.sup.2 independently each ocurrence are C.sub.1-30 hydrocarbyl,the molar ratio of complex to organoaluminum hydrocarbyloxide compound being from 1:0.1 to 1:100.

Abstract: A transition metal complex represented by the formula [1] ##STR1## wherein M is a transition metal atom of the group 4 of the periodic table of elements; Cp is a group having a cyclopentadiene type anionic skeleton; A and G are each a divalent residue containing an atom of the group 15 or 16 of the periodic table of elements and may be the same with or different from each other; X.sup.1, X.sup.2, R.sup.1, R.sup.2, R.sup.3 and R.sup.

Abstract: A solid, hydrocarbon-insoluble, catalyst component useful in polymerizing olefins containing magnesium, titanium, and halogen further contains an internal electron donor comprising ##STR1## wherein R is selected from C.sub.1 -C.sub.8 alkyl, C.sub.6 -C.sub.9 aryl or C.sub.1 -C.sub.8 alkoxy groups; and wherein X and Y are N-R', O, P(O)(OR'), P(O)R', or S, and R' is selected from hydrogen, C.sub.1 -C.sub.8 alkyl and alkoxy, and C.sub.6 -C.sub.9 aryl groups, provided that up to two Y groups may be CR'.sub.2 groups.

Abstract: A catalyst containing the combination which comprises:(a) an aluminoxane, a compound of the formula R.sub.x NH.sub.4-x, BR'.sub.4, R.sub.x PH.sub.4-x, BR'.sub.4, R.sub.3 CBR'.sub.4 or BR'.sub.3, or a mixture thereof wherein X is an integer from 1 to 4 and the radicals R are identical or different and are a C.sub.1 -C.sub.10 -alkyl or a C.sub.6 -C.sub.18 -aryl or 2 radicals R together with the atom joining them form a ring, and the radicals R' are identical or different and are a C.sub.6 -C.sub.18 -aryl which optionally are substituted by alkyl, haloalkyl or fluorine, and(b) a metallocene of the formula VI ##STR1## in which M.sup.1 is titanium, zirconium, hafnium, vanadium, niobium or tantalum,R.sup.1 is (C.sub.3 -C.sub.20)alkyl, (C.sub.6 -C.sub.14)aryl, (C.sub.4 -C.sub.10)alkoxy, (C.sub.2 -C.sub.10)alkenyl, (C.sub.7 -C.sub.20)arylalkyl, (C.sub.7 -C.sub.20)alkylaryl, (C.sub.6 -C.sub.10)aryloxy, (C.sub.1 -C.sub.10)fluoroalkyl, (C.sub.6 -C.sub.10)halogenoaryl, (C.sub.2 -C.sub.10)alkynyl; a radical --SiR.sup.6.

Abstract: Catalyst compositions that are highly tolerant of catalyst poisons comprising a catalytic derivative of a Group 4 metallocene metal complex and an Group 13 metal compound according to the formula R.sup.1.sub.2 M"(NR.sup.2.sub.2),wherein R.sup.1 and R.sup.2 independently each occurrence is a hydrocarbyl, silyl, halocarbyl, halohydrocarbyl, hydrocarbyl-substituted silyl, halocarbyl-substituted silyl, or halohydrocarbyl-substituted silyl group, said R.sup.1 and R.sup.2 having from 1 to 30 carbon, silicon, or mixtures of carbon and silicon atoms, andM" is a Group 13 metal,the molar ratio of complex to Group 13 compound being from 1:0.1 to 1:100.

Abstract: Catalysts for polymerizing olefins, diolefins and/or acetylenically unsaturated monomers comprising biscyclopentadienyl, Group 4 transition metal complexes formed with conjugated dienes wherein the diene is bound to the transition metal either in the form of a .sigma.-complex or a .pi.-complex in combination with a cocatalyst or subjected to bulk electrolysis in the presence of compatible, inert non-coordinating anions.

Abstract: This invention is directed to a process for the preparation of a supported metallocene catalyst, said process comprising preparing a precursor catalyst material by dissolving a magnesium halide in an electron donor solvent in which the magnesium halide is completely soluble, heating the solution to a temperature in the range of 20.degree. C. to the boiling point of the respective electron donor for a period ranging between 10 to 60 minutes, separately preparing a solution of the metallocene compound into the same electron donor solvent, heating the solution to a temperature in the range of 25.degree. C. to 70.degree. C. for a period ranging between 0.1 to 0.5 hrs., mixing the two solutions to obtain a homogenous solution of catalyst precursor compound, stirring and maintaining this resulting homogenous solution at a temperature in the range of 50.degree. C. to 70.degree. C. for a period of 0.5 to 2 hrs.

Abstract: The present invention is directed to a process for the preparation of a solid magnesium halide supported metallocene catalyst having a transition metal selected from the group consisting of IIIB, IVB, VB and VIB of the periodic table, which comprises preparing a slurry of magnesium metal in an electron donor solvent; heating the slurry of magnesium metal to 0.degree. C. to 50.degree. C. for a period of 10 minutes to 4 hr.; adding a dihaloalkane compound to said slurry to obtain a homogeneous solution of a support (solution A); separately preparing a solution of a metallocene compound in the same electron donor solvent as solution A (solution B); heating the solution B to 0.degree. C. to 50.degree. C. for a period ranging between 10 minutes and 1 hr., adding solution B to solution A over a period ranging between 10 minutes to 2 hrs. while maintaining the temperature in the range of 0 to 50.degree. C.

Abstract: A method of making a solid, substantially dry olefin polymerization procatalyst precursor is disclosed whereby a solid precursor containing magnesium and titanium is formed in a slurry or solution, the solid then is separated from the solution and then dried at a temperature above 50.degree. C. for over an hour. Solid, substantially dry olefin polymerization procatalyst precursors made by the method also are disclosed, whereby the precursors are easier to handle, have better flowability, reduced clumpness and provide catalysts that can be used to produce polymers having improved extrudability, less filter clogging, less "talc"-like polymer particles of <10 micron in size and reduced polymer product segregation in storage.

Abstract: Olefin polymerization catalysts are described that comprise the reaction product of (a) a metallocene and/or a Ziegler-Natta catalyst compound (TICl.sub.4, etc.,) and (b) a liquid clathrate composition formed from (i) an aluminoxane, (ii) an organic, inorganic or organometallic compound, and (iii) an aromatic solvent. These liquid clathrates are obtained by the reaction, in aromatic solvents, of aluminoxanes such as, methylaluminoxane, with organic, inorganic or organometallic compounds that form stable clathrates with the aluminoxane and the solvent.

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: A catalyst for the production of a vinyl polymer, which comprises: in combination, (A) a transition metal complex of the formula: ##STR1## wherein each of T.sup.1, T.sup.2, T.sup.3 and T.sup.4, independently of each other, is C.sub.1-20 -alkyl or C.sub.6-20 -aryl, M is a Group IV-VI transition metal and Q is C.sub.1-20 -alkoxy, (B) an aluminoxane or ionic compound having a non-coordinating anion and a cation and (C) a Lewis acid.Component (B) can be a combination of an aluminoxane and an ionic compound having a non-coordinating anion and a cation.

Abstract: The invention addresses Group 5 metal compounds suitable as polymerization catalysts characterized by comprising one Group 15 element polyanionic ancillary ligand and three single or multidentate univalent ligands comprising Group 14-16 elements bound to the Group 5 metal, but excluding cyclopentadienyl ligands. The invention Group 5 metal compounds can be generically represented by the chemical symbols(1) ?RJ!MR'.sub.3, and(2) ?(RJ)Zn(Q)!MR'.sub.2where M is a Group 5 transition metal, preferably vanadium; J is a Group 15 heteroatom ligand covalently bound to M, preferably nitrogen; R is a substituted or unsubstituted aryl, hydrocarbyl or organometalloid group covalently bound to J; each R' is, independently, a uninegative ligand, e.g.

Abstract: There are disclosed a transition metal compound of the general formula RMX.sub.a-1 L.sub.b (R is 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 effective for producing highly syndiotactic polystyrene minimized in residual metals amounts at a low cost in enhanced efficiency.