Abstract: Spherical catalyst components for the polymerization of olefins comprising a titanium compound and optionally an electron-donor supported on anhydrous magnesium chloride, characterized by a surface area between 20 and 250 m.sup.2 /g, porosity between 0.25 and 0.5 cc/g, and an X-ray spectrum where the magnesium chloride reflections are present at 2 .nu. of 35.degree. and 14.95.degree., or where the reflection at 35.degree. is substituted by a halo with the maximum intensity between 33.5.degree. and 35.degree. and the reflection of 2 .nu. at 14.95.degree. is absent.

Abstract: A process for producing an .alpha.-olefin polymer which comprises polymerizing an .alpha.-olefin in the presence of a catalyst system comprising(A) a solid catalyst component containing at least titanium, magnesium, halogen, and electron donor and(B) a sterically hindered aluminum amide compound represented by the general formula ##STR1## wherein, R.sup.1 through R.sup.5 denote each a hydrocarbon group of 1 to 20 carbon atoms, L denotes an alkoxy group of 1 to 20 carbon atoms and/or halogen, l is 2 or 3, x is defined by 0<x<1, y is defined by 0.ltoreq.y<3, and z is defined by 0<z<3 with the proviso that x+y+z=3.

Abstract: Porous particles of MgCl.sub.2 having the form of essentially regular polyhedrons with six or eight faces in which the paired symmetrically opposite faces are essentially parallel, two of which faces are large and elongated and form the top face and the bottom face of a polyhedron such that on each of them the longest diagonal (D) is larger than the shortest distance (d) separating two opposite sides, which large elongated faces are surrounded essentially perpendicularly by the other essentially rectangular faces that form the sides of the said polyhedron, the length of the smaller side (e) of each of the said essentially rectangular faces being less than the shortest distance (d) separating the two opposite sides of the large elongated faces, catalytic components supported on the particles, catalyst systems utilizing the catalytic products, process for making the particles, and polyolefins obtained utilizing the catalytic systems.

Abstract: Catalytic solids based on titanium trichloride complex, usable for the stereospecific polymerization of alpha-olefins, obtained by heat treatment, in the presence of a halogenated activating agent, of the liquid material resulting from bringing TiCl.sub.4, pretreated with an electron-donor compound, into contact with a composition (C) corresponding to the general formulaAlR.sub.p (Y) .sub.q X .sub.3-(p+q)in whichR represents a hydrocarbon radical or a hydrogen atom;Y represents a group chosen from --OR', --SR' and --NR'R", in which R' and R" each represent a hydrocarbon radical or a hydrogen atom;X represents a halogen;p is an arbitrary number such that 0<p<3; andq is an arbitrary number such that 0<q<3; the sum (p+q) being such that 0<(p+q).ltoreq.3.These catalytic solids of controllable porosity permit the production of a wide range of propylene polymers, in particular the propylene and ethylene copolymers known as "block" copolymers.

Abstract: A process for preparing polymers of 1-olefins and a catalyst for such process are provided. The catalyst is comprised of a solid titanium halide-containing compound and an alkylaluminum hydride.

Abstract: The invention relates to a method for the preparation of a supported procatalyst intended for the polymerization of olefines, in which particles are formed of magnesium dihalide and alcohol, the particles are reacted with an organic compound of a metal from the groups I-III, the thus obtained particulate product is activated by means of a titanium and/or vanadium compound and optionally a donor, and optionally a prepolymerization is carried out for the activated particles. A problem of such a method is how to form particles of magnesium dihalogenide and alcohol having a structure advantageous for the polymerization of olefins. The problem has in the present invention been solved so that the particles are formed by spray crystallizing (spray freezing) a mixture of magnesium dihalide and alcohol to complex particles of magnesium dihalide and alcohol. The hydroxyl content of the particles so obtained is much greater than earlier, which results in a much more active procatalyst than the preceding ones.

Abstract: A catalyst, a method of preparing the catalyst, and a method of using the catalyst with a suitable cocatlayst in the polymerization or copolymerization of 1-olefins are disclosed. The catalyst is prepared by: a) contacting a group IIA organometallic compound, like 2-methylpentanoxymagnesium chloride, or a Group III organometallic compound, like triethylaluminum, or a combination thereof, with a porous or nonporous biodegradable substrate having active surface hydroxyl groups, like cellulose, to provide a modified biodegradable substrate; then b) contacting the modified biodegradable substrate with a transition metal compound, such as a transition metal halide or alkoxide, like titanium tetrachloride or vanadium(V)trichloride oxide, to form discrete catalyst particles. The catalyst particles are used in conjunction with a suitable cocatlalyst, like triethylaluminum, in the homopolymerization or copolymerization of 1-olefins.

Abstract: This invention relates to a two component catalyst system for the polymerization of metathesis polymerizable cycloolefins, comprising(a) a pure tungsten-imido compound (procatalyst) of the formulaW(NR.sup.1)X.sub.4-x (OR.sup.2).sub.x.L.sub.ywherein x=0, 1, 2, 3 or 4; y=0 or 1; R.sup.1 and R.sup.2 are alkyl, phenyl, phenyl-substituted phenyl, phenylalkyl or halogen substituted derivatives of alkyl, phenyl, phenyl-substituted phenyl or phenylalkyl; X=Br or Cl; where alkyl has 1 to 8 carbon atoms, phenyl-substituted phenyl has 12-18 carbon atoms and phenylalkyl has 7 to 20 carbon atoms; L is a donor ligand; and(b) an activator compound selected from organometals and organometal hydrides with tri-n-butyltin hydride and tri-octyltin hydride the most preferred.

Abstract: A cocatalyst for use in association with a catalytic component comprising a titanium compound and an internal electron donor on a magnesium halide support for the polymerization of propylene alone or propylene with ethylene or a C.sub.4 to C.sub.12 alpha-olefin, said cocatalyst consisting essentially of an organic aluminum compound and an external electron donor consisting essentially of a non-aromatic silane with two Si--O--C bonds and a monoether and/or a silane with a single Si--O--C bond and the resultant catalyst wherein such cocatalyst is combined with a catalytic component known for use in polymerizing propylene.

Abstract: A catalyst or catalyst component for the polymerization or copolymerization of alpha-olefins in the slurry phase is formed by a process comprising forming a solution of a magnesium-containing species in a liquid and precipitating solid particles from the solution of the magnesium-containing species by treatment with a transition metal halide in the presence of at least one of a tetrabutoxysilane and a tetrabutoxytitanate.

Abstract: A polymerization catalyst system is formed by combining an organometal compound and a transition metal compound to produce a catalyst A; and combining catalyst A and a catalyst B comprising a rare earth complex having a formula Cp.sub.n MX.sub.4-n.M'L.sub.x, wherein Cp is cyclopentadienyl or cyclopentadienyl substituted with an alkyl or alkyl silyl radical, M is yttrium, scandium or a rare earth metal having an atomic number in the range of 57 to 71, M' is an alkali metal, L is a suitable electron donor ligand, X is a halogen, n is 1 or 2, and x is a number corresponding to the value needed to form a stable complex.Optionally catalyst A is contacted with a rare earth metal halide.Optionally catalyst B is contacted with an alkali or alkaline earth metal alkyl.Optionally a hydrocarbyl aluminum compound can be contacted with catalyst B or with the catalyst system.

Abstract: This invention relates to a catalytic component for the polymerization of .alpha.-olefins and provides a catalytic component of magnesium support type capable of exhibiting a high stereoregularity while maintaining an improved strength as well as a high catalytic activity. The features thereof consist in a catalyst component for the polymerization of .alpha.-olefins obtained by contacting (A) a solid component comprising, as essential components, magnesium, titanium, a halogen and an electron-donating compound with (D) an olefin in the presence of (B) a trialkylaluminum and (C) a dimethoxy group-containing compound represented by the general formula R.sup.1 R.sup.2 Si(OCH.sub.3).sub.2 where R.sup.1 and R.sup.2 are, same or different, aliphatic hydrocarbon groups with 1 to 10 carbon atoms and having a volume, calculated by the quantum chemistry calculation, of 230 to 500 .ANG..sup.3 and an electron density of oxygen atoms in the methoxy group, calculated similarly, ranging from 0.685 to 0.800 A. U.

Abstract: A vanadium-based catalyst system is treated with an ether as a means of enhancing catalyst activity and polymer productivity.

Abstract: An improved high activity olefin polymerization catalyst catalyzes the production of polymeric lower .alpha.-olefin having good properties and a relatively narrow particle size distribution. The catalyst is produced from an organoaluminum cocatalyst, a selectivity control agent and a novel olefin polymerization procatalyst which is prepared by contacting a tetravelent titanium halide, a halohydrocarbon, an electron donor and the solid procatalyst precursor obtained by heating an adduct of a carbonated magnesium ethoxide and a phenolic compound of enhanced acidity.

Abstract: The present invention relates to solid catalyst components for olefin polymerization formed by prepolymerizing at least two types of .alpha.-olefin on an olefin polymerization catalyst comprising a solid titanium catalyst component, an organometallic compound catalyst component, and if necessary, an electron donor, to olefin polymerization catalyst comprising said solid catalyst component for olefin polymerization, an organometallic compound catalyst component, and if necessary, an electron donor, and to processes for olefin polymerization using said olefin polymerization catalyst.According to the present invention, there can be manufactured olefin polymer particles having low adhesive among the polymer particles as well as good particle distribution and excellent granular properties even when they contain a large amount of an amorphous olefin polymer portion.

Abstract: A complex alkoxide compound containing magnesium, titanium and boron species comprises the reaction product of elemental magnesium, titanium tetraalkoxide, an alkyl borate ester and alkanol at elevated temperature in an inert diluent. This complex alkoxide compound is contacted with a tetravalent titanium halide, a halohydrocarbon and an electron donor to form an olefin polymerization procatalyst. Contact of the procatalyst with an organoaluminum cocatalyst and a selectivity control agent produces a high activity catalyst for the polymerization of lower .alpha.-olefins to polymer product of good properties in good catalyst productivity.

Abstract: Ziegler polymerization of .alpha.-olefins is disclosed which is characterized by a solid catalyst component. The solid catalyst component, Component (A), comprises Sub-component (i) which is a solid catalyst component for Ziegler catalysts comprising Ti, Mg and a halogen; Sub-component (ii) which is a silicon compound having a plurality of a bond represented by a formula: Si--OR.sup.1R.sup.1.sub.m X.sub.n Si(OR.sup.2).sub.4-n-mwherein R.sup.1 indicates a hydrocarbyl group of 1 to 8 carbon atoms, Sub-component (iii) which is a vinylsilane compound, and Sub-component (iii) which is an organometal compound of a metal of Groups I to IV of the Periodic Table. No need of an outside electron donor may be required, and the polymer produced is improved in its content of a "tacky" polymer.

Abstract: The invention relates to catalysts for ethylene polymerization or copolymerization to produce film quality product which exhibits improved FDA hexane extractables. The invention also relates to catalysts for ethylene polymerization or copolymerization to produce film quality product which exhibits improved dart impact resistance. The invention relates to catalysts for ethylene polymerization or copolymerization to produce film quality product which exhibits improved MD tear properties.

Abstract: A Zeigler-Natta type catalyst suitable for polymerizing propylene comprising a preactivated support coated with 0.1 to 10 g of homopolymer or copolymer of propylene. The preactivated support which comprises magnesium chloride and 1 to 20% by mol of an electron donor free from labile hydrogen and from ester function, is in the form of spherical particles having a mean diameter by mass of 10 to 100 microns and a ratio of the mean diameter by mass to the mean diameter by number of less than 2.0. The preactivated support is treated with at least one internal electron donor compound and coated by contacting the treated support with an alkyl aluminium halide and propylene, optionally together with ethylene and/or a C.sub.4-8 alpha-olefin, in the absence of an external electron donor compound.

Abstract: The invention relates to a method for the preparation of a supported polymerization catalyst in a multi-function reactor (1) which is equipped with a mixer (2) and at the bottom of which there is fitted a downward substantially conically converging sieve tray (3), possibly detachable, and in which there are carried out, as required for the preparation of the catalyst, an activation stage, i.e. the treatment of the catalyst support with a transition metal compound, washing stages using a suitable solvent, and drying stages using an inert gas, and possibly a prepolymerization of a suitable monomer by means of the obtained activated catalyst and a co-catalyst and possible other compounds, for example a polymerization medium.

Abstract: The present invention relates to a catalyst for the polymerization of olefins, and provides a catalyst component of magnesium support type which has a high catalytic activity as well as improved catalytic grain strength sufficient for practical use and which hardly deteriorates even after storage for a long time. The catalyst component is obtained by contacting(a) metallic magnesium with(b) a hydrocarbon represented by the general formula RX wherein R is a hydrocarbon group of 1 to 20 carbon atoms and X is a halogen atom, then contacting the resulting composition with(c) a compound represented by the general formula X.sup.1 nM(OR.sup.1).sub.m-n wherein X.sup.1 is a hydrogen atom, halogen atom or a hydrocarbon group of 1 to 20 carbon atoms, M is a boron, carbon, aluminum, silicon or phosphorus atom, R.sup.1 is a hydrocarbon group of 1 to 20 carbon atoms, m is the atomic valence of M and m>n.gtoreq.0, and(d) a titanium alkoxide represented by the general formula Ti(OR.sup.2).sub.4 wherein R.sup.

Abstract: A complex, magnesium-containing, titanium-containing solid olefin polymerization procatalyst precursor is produced by reaction of magnesium alkoxide, titanium tetraalkoxide and a phenolic compound followed by removal of alkanol. Conversion of this solid to an olefin polymerization procatalyst and the procatalyst to an olefin polymerization catalyst results in a catalyst which is used to polymerize lower .alpha.-olefin monomers. The polymer product is obtained in good yield and has good properties including a relatively high bulk density and a relatively narrow particle size distribution.

Abstract: A solid catalyst for polymerizing an olefin is prepared from an organometallic compound, a fine-particle carrier, an aluminoxane, a compound of group IVB transition metal in periodic table, and an olefin polymer produced in a preliminary polymerization. The catalyst has a high polymerization activity and is capable of producing an olefin polymer having a narrow molecular- weight distribution. When the catalyst is used for producing an olefin copolymer, the resulting copolymer has both narrow molecular-weight distribution and composition distribution.

Abstract: A process for producing an ethylene copolymer, which comprises contacting ethylene and an .alpha.-olefin having 3-20 carbon atoms such as hexene with a catalyst comprising the following components (A) and (B):Component (A)a solid catalyst component for a Ziegler type catalyst which is obtained by contacting a magnesium halide such as MgCl.sub.2, a titanium halide such as TiCl.sub.3 and tetrahydrofuran and has a molar ratio of tetrahydrofuran/titanium in the range of 3-20; andComponent (B)an alumoxane having a structure of ##STR1## with an average polymerization degree m in the range of 3-50 and having a hydrocarbyl group R.sup.3 of 1-10 carbon atoms such as hexaisobutyltetraalumoxane where R.sup.3 is isobutyl and m is 4.

Abstract: Catalyst components for the polymerization of olefins and catalysts obtained therefrom, said components comprising a porous metal oxide on which a magnesium dihalide, and a titanium halide or titanium halogen alcoholate and a compound containing two or more ether groups having specific reactivity properties towards MgCl.sub.2 and TiCl.sub.4 are supported.

Abstract: A catalyst component for olefin polymerization composed of a solid component (IV) and capable of affording a supported type catalyst composed of large particles and having a sharp particle size distribution is provided,which solid component (IV) is obtained bystep A of reacting an organic Mg compound of a specified formula with a 1-20C saturated or unsaturated mono- or polyhydric alcohol C in the presence of CO.sub.

Abstract: Supported olefin, e.g., alpha-olefin, polymerization catalyst compositions, such as Ziegler-Natta catalysts, are modified by using porous, polymer particles having an average pore diameter of at least about 10 .ANG. as the catalyst support. The resulting catalyst composition is more active than refractory oxide-supported catalysts and it is not susceptible to deactivation by catalyst poisons, such as oxygen or water. Additionally, the polymer particles need not be calcined prior to the catalyst synthesis.

Abstract: A method for producing a stereoregular polyolefin in the presence of a catalyst comprising a transition metal compound and an organometallic compound, wherein a catalyst system is employed which comprises (i), (ii) and (iii): (A) a solid catalyst component obtained by reacting to a uniform solution containing (i) at least one member selected from the group consisting of metallic magnesium and an organic hydroxide compound and an oxygen-containing organic magnesium compound, (ii) a compound of Group IIIB of the Periodic Table, and (iii) an oxygen-containing organic silicon compound, (iv) at least one aluminum halide, to obtain a solid product, and reacting to the solid product, (v) an electron donative compound, and (vi) a titanium halide compound; (B) at least one member selected from the group consisting of organometallic compounds of metals of Groups IA, IIA, IIB, IIIB and IVB of the Periodic Table; and (C) an electron donative compound.

Abstract: Improved lower .alpha.-olefin polymerization catalysts are produced from an organoaluminum cocatalyst, a selectivity control agent and a specified magnesium-containing, titanium-containing, halide-containing procatalyst. The procatalyst is produced from an electron donor, tetravalent titanium halide and a complex alkoxide compound formed from magnesium alkoxide, titanium alkoxide and a phenolic compound. The catalyst is utilized produce poly-.alpha.-olefin in good yield, which polymer is characterized by a relatively low xylene solubles content and a relatively high bulk density.

Abstract: A process for producing a catalyst component for olefin polymerization is provided, which process comprises spraying a solution of a magnesium compound e.g. MgCl.sub.2 and an alcohol such as MgCl.sub.2. nROH (wherein R is 1-10 C alkyl and n is 3-6) into a cooled spray column to obtain a spherical solid component (carrier) without any substantial vaporization of the alcohol, followed by partly drying the component for a time till a specified ratio of the alcohol/MgCl.sub.2 is attained, and then subjecting the resulting component to treatment with a titanium halide and an electron-donating component, the resulting component having a large particle diameter, without any dispersion of the solvent content in the component particles and also without any breakage of the particles when subjected to treatment with the titanium halides.

Abstract: The present invention relates to a process for preparing a Ziegler-Natta type catalyst based on a vanadium compound. The process comprises sequentially contacting within a liquid hydrocarbon a spheroidal support comprising (i) MgCl.sub.2 free from any Mg-C bond and (ii) an electron-donor D1 free from labile hydrogen, an electron-donor D2 containing labile hydrogen and an organometallic compound capable of reducing a vanadium compound, (2) washing the solid product with a liquid hydrocarbon resulting from the contacting, and (3) contacting the washed solid product with one or more vanadium compounds soluble in the liquid hydrocarbon, comprising halogen atoms and alkoxy radical, both being bonded to the same or different vanadium atoms. The catalyst which consists of spheroidal particles without fines, is very active in olefin polymerization and is particularly suitable for producing elastomeric copolymers of propylene.

Abstract: A catalyst system for the polymerization of alpha-olefins comprising:(a) a solid precursor comprising the reaction product of (i) a halogenated vanadium compound wherein the vanadium has a valence of 2 to 5; (ii) a magnesium compound; and (iii) an inside electron donor wherein the molar ratio of inside electron donor to vanadium compound is in the range of about 0.2:1 to about 2:1; the atomic ratio of magnesium to vanadium is in the range of about 3:1 to about 40:1; and the reaction product (A) is a solid having a surface area greater than about 10 square meters per gram or (B) is adsorbed on the surface of an inorganic support having a surface area greater than about 10 square meters per gram;(b) a hydrocarbyl aluminum cocatalyst wherein the atomic ratio of aluminum to vanadium is in the range of about 2:1 to about 300:1; and(c) an outside electron donor wherein the molar ratio of outside electron donor to aluminum is in the range of about 0.02:1 to about 1:1.

Abstract: A catalyst for use in polymerization of olefins which comprises a carrier mainly composed of a magnesium compound precipitated from a solution and a catalytic component supported on the carrier and selected from titanium halides, vanadyl halides and vanadium halides is described. The catalyst is obtained by a process which comprises: (A) mixing (a) at least one magnesium compound with (c) a saturated or unsaturated monohydric or polyhydric alcohol for reaction in dissolved state in the presence of (b) carbon dioxide in an inert hydrocarbon solvent to obtain component (A); (B) subjecting the component (A) to mixing and reaction with (d) a titanium and/or a vanadyl halide and/or a vanadium halide of the general formula, VX.sub.r (OR.sup.8).sub.4-r, and also with (e) at least one boron compound, Si compound and/or Siloxane compound thereby obtaining solid product (I); (C) reacting the solid product (I) with (f) a cyclic ether with or without R.sup.

Abstract: Ziegler-Natta-type catalyst systems contain as active constituentsa) atitanium-containing solid component which contains titanium, magnesium, halogen and a norbornadienedicarboxylate of the formula I ##STR1## as electron donor, where R.sup.1 and R.sup.2 are each C.sub.1 -C.sub.8 -alkyl or 5- to 7-membered cycloalkyl which in turn can carry C.sub.1 -C.sub.10 -alkyl groups,b) an aluminum component andc) another electron donor component,and are particularly suitable for preparing polypropylene and copolymers of propylene with minor amounts of other .alpha.-olefins with 2 to 8 carbon atoms.

Abstract: A solid hydrocarbon-insoluble, alpha-olefin polymerization catalyst component with superior activity, stereospecificity and morphology characteristics comprising the product formed by A) forming a solution of a magnesium-containing species from a magnesium alkyl (or hydrocarbyl) carbonate or a magnesium carboxylate; B) precipitating solid particles from such solution by treatment with a transition metal halide; C) reprecipitating such solid particles from a mixture containing a cyclic ether; D) treating the reprecipitated particles with a transition metal compound and an electron donor; and E) drying the resulting solid particles such that the residual volatile hydrocarbon content is between 0.1 and 0.9 weight percent.

Abstract: An olefin polymerization catalyst comprising:(A) a solid catalyst component containing a trivalent titanium, which is represented by the composition formulaMg.sub.m Ti(OR).sub.n X.sub.p [ED].sub.q(wherein R is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen, ED is a electron donative compound, and m, n, p and q are each a number satisfying 1.ltoreq.m.ltoreq.51, 0<n.ltoreq.5, 5.ltoreq.p.ltoreq.106 and 0.2.ltoreq.q.ltoreq.2) obtained by reducing a titanium compound represented by the general formula Ti(OR.sup.1).sub.a X.sub.4-a (wherein R.sup.1 is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen atom and a is a number satisfying 0<a.ltoreq.

Abstract: An improved support vanadium catalyst, especially an improved Beran et al. catalyst system and ethylene polymerization process in which the improvement derives from fixing the promoter to a component of the catalyst composition such that it is a molecularly structural component of the catalyst and thus is not separately fed to the polymerization reaction, but instead is part of the catalyst composition fed to the reaction.

Abstract: The present invention relates to a process for preparing a Ziegler-Natta type catalyst based on a vanadium compound precipitated on a MgCl.sub.2 spherical support. The catalyst preparation consists of contacting within a liquid hydrocarbon a vanadium-reducing agent chosen from organometallic compounds with a vanadium compound soluble in the liquid hydrocarbon containing at least one halogen and one alkoxy group, and with a support containing (i) MgCl.sub.2 free from Mg-C bond and (ii) an organic electron donor compound free from labile hydrogen. The support consists of spherical particles having a well-defined diameter and a narrow particle size distribution. The catalyst is particularly suitable for manufacturing in a gas phase process elastomeric copolymers of propylene.

Abstract: Catalyst components for the polymerization of olefins comprising a titanium halide or alkoxyhalide and an electron-donor compound selected from ethers having two or more ether groups and containing at least one heteroatom selected from the group consisting of N, S, P, Si, non-ether O and halogen atoms or at least one double bond, or both at least one heteroatom and at least one double bond, supported on a magnesium halide in active form.Catalysts obtained from said catalyst components and an Al-alkyl compound, as well as catalysts obtained by the reaction of an Al-alkyl compound and an ether having the above defined characteristics with a solid catalyst component comprising a titanium halide or alkoxyhalide and an electron-donor compound having particular characteristics of extractability with Al-triethyl, supported on activated magnesium halide.

Abstract: A vanadium catalyst component for the polymerization of 1-olefins and a process for making said catalyst component are disclosed. The catalyst component is prepared by fluoriding a support comprising silica. Use of the catalyst component provides a catalyst with increased activity, increased response to hydrogen for chain termination, increased response to comonomer for resin density reduction, and allows the molecular weight distribution of the polymers to be independently controlled by controlling the amount of fluorination and the fluorination temperature.

Abstract: Disclosed are catalyst components for the polymerization of olefins comprising the product of the reaction of a tetravalent titanium halide or alkoxy titanium halide and an electron-donor compound with a solid obtained by the reaction of a metal oxide containing surface hydroxyls, preferably together with chemically uncombined water, with an organometallic magnesium compound used in a quantity which does not cause reduction of the titanium in the subsequent reaction with the tetravalent titanium compound.

Abstract: A vanadium-based catalyst is treated with a polysiloxane oil as a means of enhancing catalyst activity and polymer productivity.

Abstract: A Zeigler-Natta type catalyst suitable for polmerizing propylene comprising a preactivated support coated with 0.1 to 10 g of homopolymer or copolymer of propylene. The preactivated support which comprises magnesium chloride and 1 to 20% by mol of an electron donor free from labile hydrogen and from ester function, is in the form of spherical particles having a mean diameter by mass of 10 to 100 microns and a ratio of the means diameter by mass to the mean diameter by number of less than 2.0. The preactivated support is treated with at least one internal electron donor compound and coated by contacting the treated support with an alkyl aluminium halide and propylene, optionally together with ethylene and/or a C.sub.4-8 alpha-olefin, in the absence of an external electron donor compound.

Abstract: A vanadium-based catalyst is treated with certain alkylaluminum alkoxide compounds as a means of narrowing and effectively regulating the molecular weight distribution of the polymers produced with the catalyst.

Abstract: A catalyst and method is provided for the production of ultra-high molecular weight polymers characterized as having an inherent viscosity of above 12.0 by contacting ethylenically unsaturated monomers with a dual electron donor catalyst under polymerization conditions.

Abstract: A catalyst system comprising(A) a halogen compound of trivalent titanium,(B) an organo-aluminum compound of the formula,R.sub.3-(m+n) AlY.sub.m X.sub.nwhereinY is a group having at least one of oxygen, nitrogen, sulfur and phosphorus atoms linked to the aluminum atom, R is a hydrogen atom, an alkyl having 1 to 18 carbon atoms, an alkenyl having 2 to 18 carbon atoms, a cycloalkyl having 3 to 18 carbon atoms, an aryl having 6 to 18 carbon atoms, or an aralkyl having 7 to 18 carbon atoms,X is a halogen atom, and m and n are numbers satisfying the equations, 0<m<1, 0.ltoreq.n<2, 0<m+n.ltoreq.2, and(C) an electron-donor, and a method for producing an olefin polymer which comprises polymerizing olefins using said catalyst system. According to this method, highly crystalline olefin polymers having a broad melecular weight distribution can be produced.

Abstract: An olefin polymerization catalyst component subjected to successive preliminary polymerization treatment using each of a straight chain alpha-olefin having 2 to 5 carbon atoms and 3-methyl-1-butene; an olefin polymerization catalyst using the olefin polymerization catalyst component; a process for polymerizing olefin(s) which comprises polymerizing or copolymerizing olefin(s) in the presence of the olefin polymerization catalyst; and a film and an injection-molded article of polypropylene which is prepared by the process are also provided.

Abstract: A process for the preparation of a solid catalyst of the Ziegler-Natta type comprises precipitating the solid catalyst in a liquid hydrocarbon medium by reacting (A) a solution of a soluble magnesium alkoxide and (B) a transition metal halide which is a halide of Ti (IV), a halide of V (IV) or a halide of VO (III) in the presence of (C) at least one transition metal alkoxide which is free from halogen and soluble in liquid hydrocarbon. The precipitated solid catalyst consists of spheroidal particles having a mean diameter by mass of from 10 to 70 microns and a narrow particle size distribution such that the ratio of mean diameter by mass to the mean diameter by number is greater than 1.2 and smaller than 2.0.

Abstract: Supported catalysts component for producing ethylene-propylene elastomers comprising a compound represented by the formula:(1) [V.sub.3 O(RCO.sub.2) (ED).sub.3 ].sub.2. V.sub.2 O.sub.2 X.sub.6, or(2) V.sub.3 O(RCO.sub.2).sub.6 (ED).sub.3wherein R is alkyl, cycloalkyl, aryl and haloalkyl,wherein R is alkyl, cycloalkyl, aryl and haloalkyl,ED is an electron donor selected from alkyl esters of aliphatic and aromatic carboxylic acid, aliphatic ketones, aliphatic amines, aliphatic alcohols, alkyl and cycloalkyl ethers, and mixtures thereof; andX is selected from Cl--, Br--, Fl-- or RCO.sub.2.sup.--.

Abstract: A catalyst composition for polymerizing alpha-olefins is prepared by reacting a transition metal compound, e.g., titanium, with trimethylaluminum catalyst activator. In a preferred embodiment, the catalyst is supported on a porous refractory support and is prepared by additionally reacting a magnesium compound or an organomagnesium composition with the support.Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst of the invention. The polymer products have higher bulk density and produce films of greater strength than polymers prepared with similar catalysts utilizing different alkyl-aluminum activators, e.g., triethylaluminum and triisobutylaluminum.