Abstract: A catalytic system with an increased activity for the (co)polymerization of alpha-olefins comprises a catalyst of the metallocene type, which is capable of polymerizing olefins without aluminoxane, and a weak coordinating compound, which, when used in a polymerization process, enables a higher productivity than an analogous process carried out with the metallocene type catalyst per se.

Abstract: The present invention relates to a catalyst system based on fulvene cyclopentadienyl metal complexes, to a method of producing said catalyst system and to the use thereof for the polymerization and copolymerization of olefins and/or dienes.

Abstract: This invention relates to a process to polymerize olefins comprising reacting olefins with a combined catalyst system comprising a hydrogen generating olefin polymerization catalyst and from 10 ppm to 10 weight % of at least one hydrogen consuming olefin polymerization catalyst system, based upon the weight of the total catalyst present, not including any activators or supports.

Abstract: A constrained geometry single-site olefin polymerization catalyst is described. The catalyst comprises an activator and an organometallic compound that includes a Group 3 to 10 transition or lanthanide metal, M, and a multidentate ligand characterized by an indolyl group that is covalently linked to an amido group, wherein the indolyl group is &pgr;-bonded to M and the amido group is &sgr;-bonded to M. The indolyl-amido ligand is formed from readily available organic compounds and allows easy synthesis of a constrained geometry catalyst system.

Abstract: An improved catalyst for polymerizing olefins is disclosed. The catalyst comprises a Group 4 transition metal, at least one quinolinoxy or pyridinoxy ligand, and at least one benzyl ligand. Particularly when used with an activator, the benzyl-containing catalysts have exceptional activities for polymerizing olefins.

Abstract: Supported Ziegler-Natta catalyst component adapted for the polymerization of ethylene is provided. More specifically, certain organomagnesium compounds (e.g., dibutylmagnesium) which do not contain an oxygen linkage between the organo moiety and the magnesium are impregnated into a porous inorganic oxide support (e.g., agglomerated silica particles) to form a first reaction product. The first reaction product is halogenated, e.g., with HCl, to convert the organomagnesium derived component to MgCl2 thereby forming a second reaction product. The second reaction product is then treated with a transition metal compound (e.g., TiCl4), a particular type of electron donor (e.g., 2,6-dimethyl pyridine) and optionally at least one Group 2 or 13 organo metal compound (e.g., diethylaluminum chloride). The combination of the particular organomagnesium compounds and electron donor impart a low melt flow ratio and enhanced activity to resulting catalyst component.

Abstract: The present invention relates to a supported catalyst system which comprises at least one metallocene component and at least one cocatalyst component and at least one modified inorganic oxide of silicon, aluminum or mixtures thereof, wherein the modified oxide contains organic silicon radicals containing at least one of the groups nitrogen, fluorine, phosphorus or sulfur.

Abstract: A process is provided to produce a composition of matter. The process comprises contacting at least one organometal compound, at least one solid mixed oxide compound, and at least one organoaluminum compound to produce the composition.

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

Abstract: Novel catalyst systems which comprise 2-pyridine carboxaldimine nickel dihalide complexes can be used with an organoaluminum cocatalyst in slurry oligomerization or polymerization processes to oligomerize or polymerize mono-1-olefins and, optionally a higher alpha-olefin comonomer, to produce low molecular weight polymers or synthetic oils.

Abstract: Novel catalyst systems which comprise pyridine-2-carboxaldimine nickel complexes can be used with methylaluminoxane in slurry polymerization processes to polymerize mono-1-olefins and, optionally a higher alpha-olefin comonomer, to produce low molecular weight polymers.

Abstract: Catalytic systems particularly suitable for the polymerization of .alpha.-olefins containing from two to 20 carbon atoms, as well as for the copolymerization of ethylene with .alpha.-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: 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: The present invention provides a novel catalyst system which can be preferably used in the trimerization, oligomerization reaction or polymerization reaction of an olefin, and a method for the trimerization, oligomerization or polymerization reaction of an olefin, which comprises using the catalyst system. A catalyst system obtained by contacting the following components (A) to (C):(A) a chromium compound,(B) an imine compound, and(C) a metal alkyl compound, and a method for the trimerization, oligomerization or polymerization reaction of an olefin, which comprises using the catalyst system are disclosed.

Abstract: There is provided a catalyst containing a transition metal precursor having the formula (C.sub.5 R.sup.1.sub.5)MQ.sub.3, a bulky non-phenolic compound, an aluminoxane, and optionally a Br.phi.nsted acid and/or a support or spray drying material. There is also provided a polymerization process employing the catalyst composition, a polymer produced using the catalyst, and a cable produced therefrom.

Abstract: The present invention relates to MgCl.sub.2.mROH.nH.sub.2 O adducts, where R is a C.sub.1 -C.sub.10 alkyl, 2.ltoreq.m.ltoreq.4.2, 0.ltoreq.n.ltoreq.0.7, characterized by an X-ray diffraction spectrum in which, in the range of 2.theta. diffraction angles between 5.degree. and 15.degree., the three main diffraction lines are present at diffraction angles 2.theta. of 8.8.+-.0.2.degree., 9.4.+-.0.2.degree. and 9.8.+-.0.2.degree., the most intense diffraction lines being the one at 2.theta.=8.8.+-.0.2.degree., the intensity of the other two diffraction lines being at least 0.2 times the intensity of the most intense diffraction line. Catalyst components obtained from the adducts of the present invention are capable to give catalysts for the polymerization of olefins characterized by enhanced activity and stereospecificity with respect to the catalysts prepared from the adducts of the prior art.

Abstract: The invention encompasses late transition metal catalyst systems and their use in polymerization processes, particularly in solution, 2-phase suspension and super-critical phase polymerization of ethylene-containing polymers. Preferred embodiments include the use of a late transition metal catalyst system comprising a Group 8, 9, 10, or 11 metal complex stabilized by a bidentate ligand structure for polymerization under elevated ethylene pressure, or concentration, conditions.

Abstract: The present invention relates to a supported composition, to processes for its preparation and to its use for polymerizing olefins. The supported catalyst composition comprises at least one transition metal compound of subgroup 3, 4 or 5 of the ##STR1## Periodic Table of the Elements and at least one cocatalyst having the formula II in which R.sup.6 independently at each occurrence are a halogen atom or a C.sub.1 -C.sub.40 carbon-containing group, X is independently at each occurrence a C.sub.1 -C.sub.40 carbon containing group, M.sup.

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: Catalysts for olefin polymerization which consist essentially of a transition metal compound, a modified clay compound and an organic aluminum compound, wherein the modified clay compound comprises a reaction product of a clay mineral and a proton acid salt of a specific amine compound, as well as a method of polymerizing olefins using such catalysts. It is possible thereby to obtain olefin polymers with high productivity and low ash content.

Abstract: This invention provides compositions for polymerizing at least one monomer to produce a polymer. The compositions are produced by a process comprising contacting at least one organometal compound, at least one organoaluminum compound, and at least one treated solid oxide compound. The treated solid oxide compound is produced by a process comprising contacting at least one solid oxide compound with at least one electron-withdrawing anion source compound and at least one metal salt compound.

Abstract: Methods for preparing olefin polymers, and catalysts for preparing olefin polymers are disclosed. The polymers can be prepared by contacting the corresponding monomers with a Group 8-10 transition metal catalyst. The polymers are suitable for processing in conventional extrusion processes, and can be formed into high barrier sheets or films, or low molecular weight resins for use in synthetic waxes in wax coatings or as emulsions.

Abstract: Supported catalyst systems are obtainable bya) application of a mixture ofA) at least one metallocene complex andB) at elast one metal compoundto a carrier which, if required, may have been pretreated, andb) subsequent activation by reaction with a solution or suspension of a compound forming metallocenium ions.

Abstract: A process for preparing substantially random olefin copolymers containing geminally disubstituted olefin monomers is described. The geminally disubstituted olefin monomers can be represented by the generic formula R.sub.1 =R.sub.2 (R.sub.3)(R.sub.4), where R.sub.1 is CH.sub.2, R.sub.2 is C, and R.sub.3 and R.sub.4 are, independently, essentially linear hydrocarbyl groups having from 1 to 30 carbon atoms, or more, and containing one carbon atom bound directly to R.sub.2. The copolymers can be prepared by contacting at least one geminally disubstituted olefin monomer and one or more comonomers selected from the group consisting of ethylene and C.sub.3 -C.sub.20 .alpha.-olefins, optionally with one or more other coordination polymerizable monomers, with a active coordination catalyst system comprising a bridged bis(arylamido) Group 4 catalyst component.

Abstract: A catalyst precursor having the formula: ##STR1## wherein M is a Group IVB metal; each L is a monovalent, bivalent, or trivalent anion;X and Y are each heteroatoms;each Cyclo is a cyclic moiety;each R.sup.1 is a group containing 1 to 50 atoms selected from the group consisting of hydrogen and Group IIIA to Group VIIA elements, and two or more adjacent R.sup.1 groups may be joined to form a cyclic moiety;each R.sup.2 is a group containing 1 to 50 atoms selected from the group consisting of hydrogen and Group IIIA to Group VIIA elements, and two or more adjacent R.sup.2 groups may be joined to form a cyclic moiety;W is a bridging group; andeach m is independently an integer from 0 to 5.

Abstract: The invention relates to olefin polymerization using an organosilicon compound from the pyrazolyl family as an external adjuvant.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a complexing agent, a solvent, and optionally a cocatalyst. The cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a complexing agent, a solvent, and optionally a cocatalyst. Further disclosed is a process for using the composition which comprises contacting a carbonyl compound, in the presence of the composition, with an alcohol under a condition suitable for esterification, transesterification, polymerization, or combinations thereof.

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 catalyst composition is disclosed. The composition comprises a titanium compound, a phosphorus compound, an amine, a solvent and optionally a cocatalyst in which the phosphorus compound has a formula selected from the group consisting of (R.sup.1 O).sub.x (PO)(OH).sub.3-x, (R.sup.1 O).sub.y (P.sub.2 O.sub.3)(OH).sub.4-y, and combinations thereof; the amine is a tertiary amine; each R.sup.1 is independently a linear or branched alkyl radical containing from 1 to about 20 carbon atoms per radical; x is 1 or 2; and y is 1, 2, or 3; and the cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a phosphorus compound, a solvent, an amine, a solvent, and optionally a cocatalyst. The phosphorus compound, amie, and solvent are the same as those disclosed above.

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: 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: A solid titanium catalyst component ?Ia! containing magnesium, halogen, titanium and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a catalyst and a prepolymerized olefin-containing catalyst prepared by using the solid titanium catalyst component ?Ia!; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used. A catalyst and a prepolymerized olefin containing catalyst prepared by using a solid titanium catalyst component ?Ib! containing magnesium, halogen, titanium and a specific electron donor (al), and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used.

Abstract: A catalyst for use in the production of flexible polyolefins using a pro-catalyst of (a) a magnesium halide, (b) an aluminum halide, (c) a tetravalent titanium halide, (d) an electron donor comprising at least one of 2,6-lutidine, 6-chloro-2-picoline, or 2,6-dichloropyridine; and (e) a silane having the formula R.sub.1 R.sub.2 Si(OR.sub.3)(OR.sub.4), wherein R.sub.1 and R.sub.2 are each an H, C.sub.1-6 alkyl, C.sub.1-6 aryl, C.sub.5-12 cycloalkane, each of which may be unsubstituted, mono- or di-substituted, and R.sub.3 and R.sub.4 are H, C.sub.1-6 alkane, or a mono- or di-substituted C.sub.1-6 alkane, and a co-catalyst of an organometallic compound, as well as an optional external modifier that may be combined to form a catalyst. Methods for preparing the catalyst, for using the same to produce flexible polyolefin compositions having reduced stickiness and tacticity, and the flexible polyolefin compositions produced thereby are also part of the invention.

Abstract: Disclosed is a process for preparing an anhydrous magnesium halide solution, comprising a step of distilling water off from an oxygen-containing organic solvent solution of hydrous magnesium halide containing at least calcium as an impurity, to prepare an oxygen-containing organic solvent solution of anhydrous magnesium halide, wherein a potassium compound is added in said step to precipitate calcium and potassium, followed by removing the calcium and potassium. According to this process, an anhydrous magnesium halide solution scarcely containing calcium can be prepared from hydrous magnesium halide containing calcium as an impurity. Also disclosed is a process for preparing a solid titanium catalyst component for olefin polymerization, comprising contacting the anhydrous magnesium halide solution obtained by the above process with a liquid titanium compound to precipitate a solid titanium catalyst component.

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: A process is provided to modify an olefin production catalyst system which comprises contacting an olefin production catalyst system with ethylene prior to use. A process also is provided to trimerize and/or oligomerize olefins with the novel, modified olefin catalyst production system. The modified olefin production catalyst system produces less solids, such as, for example, polymer.

Abstract: A solid catalyst component (A) for olefin polymerization comprising Mg, Ti, a halogen and a cyclic organic nitrogen compound (C), a solid catalyst comprising the solid catalyst component and an organoaluminum compound, and a process for producing an olefin polymer with the catalyst.According to the present invention, there can be provided an olefin polymerization catalyst having a high catalyst activity per titanium enough to make the removal of catalyst residues unnecessary and a process for producing an olefin polymer having a low content of low molecular weight component with the catalyst.

Abstract: A catalyst for olefin polymerization is provided which comprises, as the components, a) a metallocene compound, b) an ionizing ionic compound, c) an organoaluminum compound, and d) a Lewis base compound. This catalyst has a stable active species and improves productivity of an olefin polymer without deterioration of the catalytic activity the metallocene is represented by General Formula (1) or (2) where Cp-containing ligands may be Cp, fluorenyl, indenyl or tetrahydroindenyl and where the metal is a group 4 metal of the periodic table.

Abstract: Process for the polymerization of alpha-olefins, which is carried out in the presence of a catalyst system comprising:(1) a solid based on completed titanium trichloride;(2) an organometallic compound of metals of groups IA, IIA, IIB and IIIB of the Periodic Table, and(3) an electron-donor organic compound, the solid (1) based on complexed titanium trichloride having been preactivated by being brought into contact with a preactivator comprising the product of reaction of a trialkylaluminum or alkylaluminum chloride compound (a) and of a compound (b) chosen from hydroxyaromatic compounds whose hydroxyl group is sterically hindered, then isolating the predetermined solid (1) from the medium in which it was found.This process enables propylene to be polymerized with an improved stereospecificity without any significant decrease in catalyst activity.

Abstract: A catalyst for producing a styrenic polymer which comprises an (A) transition metal compound having one and only one .pi.-ligand comprising only one indenyl group, said indenyl group bearing a substituent group at at least the 1-, 2-, or 3-positions of the indenyl ring, and wherein the transition metal is preferably at least one metal selected from the group consisting of titanium, zirconium, hafnium, niobium and tantalum, and optionally (B) at least one compound selected from the group consisting of 1 an aluminoxane and 2 an ionic compound comprising an anion that does not coordinate to the transition metal compound of component (A) in its cationic form, and a cation, and further optionally (C) a Lewis acid; and a process for producing a styrenic polymer using the catalyst.

Abstract: A catalyst composition comprising: a) (i) a catalyst containing at least one cycloalkadienyl ligand substituted with at least one electron donor residue and coordinated with a metal selected from the group consisting of scandium, yttrium, and lanthanide metals; or (ii) a catalyst containing two cycloalkadienyl ligands coordinated with a metal selected from the group consisting of scandium, yttrium, and lanthanide metals, said cycloalkadienyl ligands connected by a bridging group comprising at least one Group IVA element and at least one electron donor residue; and b) an activating cocatalyst of the formula R.sub.x M', wherein R is alkyl, aryl, or hydride; M' is a Group I, II, or IIIA metal or a Group I, II, or IIIA metal complexed with oxygen, nitrogen, or a halide; and x is equal to the valence of M'.

Abstract: A solid titanium catalyst component ?Ia! containing magnesium, halogen, titanium and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a catalyst and a prepolymerized olefin-containing catalyst prepared by using the solid titanium catalyst component ?Ia!; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used. A catalyst and a prepolymerized olefin containing catalyst prepared by using a solid titanium catalyst component ?Ib! containing magnesium, halogen, titanium and a specific electron donor (a1), and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used.

Abstract: Compositions of matter useful as addition polymerization catalysts comprising a Group 4 metal complex and an adduct of tris(organyl)borane compound with a non-tertiary amine or non-tertiary phosphine compound.

Abstract: Disclosed herein is a process for the polymerization of ethylene, norbornenes and styrenes, by contacting in solution a selected nickel compound and a selected compound which is or can coordinated to the nickel with the olefin(s). The polymers produced are useful for films and molding resins.

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.