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 component (X") obtained by treating an olefin polymerization catalyst (X) formed from (A) a solid titanium catalyst component comprising magnesium, titanium, halogen and an electron donor as essential ingredients, (B) an organoaluminum compound catalyst component, and as required, (C) an electron donor with an alpha-olefin by preliminarily polymerizing the alpha-olefin in an amount of 0.1 to 500 g per gram of the solid titanium catalyst component (A) in the presence of said catalyst (X), and contacting the treated catalyst (X') with at least 0.1 mole, per gram-atom of titanium in the treated catalyst (X'), of oxygen. A process for producing the olefin polymerization catalyst component. A catalyst (Y) for olefin polymerization formed from [I] the above catalyst component (X"), [II] an organoaluminum compound catalyst component and as required [III] an electron donor. Also provided is a process for polymerizing olefins in the presence of the olefin polymerization catalyst (Y).

Abstract: A catalyst mixture is disclosed comprising (1) a particulate chromium-containing catalyst comprising inorganic oxide and chromium and (2) a particular type of particulate titanium-containing catalyst. Also disclosed is the use of this catalyst mixture to produce particularly novel olefin polymers.

Abstract: A method for producing a stereospecific polyolefin in the presence of a catalyst comprising a transition metal compound and an organometallic compound, wherein a catalyst system is used which comprises: (A) a solid catalyst component prepared by reacting a homogeneous solution containing (i-1) magnesium and a hydroxylated organic compound, (i-2) an oxygen-containing organic compound of titanium and/or (i-3) an oxygen-containing organic compound of silicon and an oxygen-containing organic compound of aluminum and/or a boron compound, with (ii) at least one aluminum halide compound to obtain a solid product, and further reacting to this solid product (iii) an electron-donative compound, (iv) a titanium halide compound, and (v) ethylene and/or an .alpha.-olefin having at least 3 carbon atoms, (B) at least one member selected from the group consisting of organometallic compounds of Groups IA, IIA, IIB, IIIB and IVB of the Periodic Table, and (C) an electron-donative compound.

Abstract: A method of producing a polyolefin, which comprises polymerizing at least one olefin in the presence of a catalyst system comprising(A) a catalyst component prepared by bringing ethylene and/or an .alpha.-olefin in contact with a solid composite obtained by reacting a reaction product, which has been produced by reacting a uniform solution containing(i) at least one member selected from the group consisting of metal magnesium and hydroxylated organic compound, and oxygen-containing organic compounds of magnesium and(ii) at least one oxygen-containing organic compound of titanium with(iii) at least one organoaluminum compound and/or(iv) at least one silicon compound, with(v) at least one aluminum halide compound, thereby allowing the ethylene and/or the .alpha.-olefin to be absorbed into the solid composite, and(B) at least one catalyst component selected from the group consisting of organometallic compounds of metals of Groups Ia, IIa, IIb, IIIb and IVb of the Periodic Table.

Abstract: The present invention relates to a process for polymerizing or copolymerizing alpha-olefins comprising, on the one hand, a prepolymerization stage by contacting one or more alpha-olefins with a Ziegler catalyst system consisting of a solid catalyst containing essentially atoms of halogen, magnesium and transition metal, and a co-catalyst consisting of an organometallic compound, and, on the other hand, a polymerization or copolymerization stage in a gas phase process by means of a fluidized bed, by contacting one or more alpha-olefins with the prepolymer produced in the first stage, process characterized in that the alpha-olefin prepolymer and polymer or copolymer are in the form of a powder consisting of particles having specific values for the transition metal content and the mean diameter by mass, and characterized in that the particle size distribution of the prepolymer is narrow and easily controlled.

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 compound with a vanadium compound soluble in the liquid hydrocarbon 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 process elastomeric copolymers of propylene.

Abstract: A polymerization catalyst useful for the polymerization of olefins is prepared by contacting a metal dihalide compound having a metal selected from Group 2 and Group 12 of the Periodic Table and a transition metal compound which is a hydrocarbyloxide of a transition metal selected from Group 4 and Group 5 to thereby form a first catalyst component; contacting the first catalyst component with at least one organoaluminum precipitating agent to form a solid product; and contacting the solid product with an ester and then an activating agent to form a catalyst. Other aspects of the invention include a catalyst produced by the above described process and a polymerization process employing the thus produced catalyst.

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: The polymerization of certain alpha-olefins in a gas phase involves the problem of agglomeration of the product into particles disadvantageous from the viewpoint of its handling. In the present invention this problem has been solved by means of a new type of process for the homo- or copolymerization of alpha-olefins. In the process the catalyst system is pretreated by contacting and reacting a transition-metal compound which is solid or on a solid carrier with an organoaluminum compound, and possibly an electron donor, in a liquid medium, and by drying the thus formed reaction product to produce a solid catalyst system. The thus pretreated solid and active catalyst system is then fed together with an alpha-olefin in the gaseous state into a gas-phase reactor, and polymerization is carried out by contacting them with each other.

Abstract: The present invention relates to an improvement of the known Ziegler catalyst which comprises a combination of a titanium-containing component and an organoaluminum component, and the present invention is characterized by a specific titanium-containing component. Namely, this titanium-containing component is obtained by contacting a known titanium-containing component of the Ziegler type catalyst which comprises Ti, Mg and a halogen, with an alkoxyalkylsilane compound which is characterized in that at least one of the alkyl groups has a branched structure. This catalyst does not require a so-called external electron donor, and no reduction of the polymerization velocity caused by the use of the electron donor is entailed. When this catalyst is used, a propylene/ethylene block copolymer in which the molecular weight of the propylene/ethylene copolymer portion and/or the polyethylene portion is increased, that is, the rigidity and impact strength are increased, can be prepared.

Abstract: The present invention relates to a process for the polymerization of ethylene or copolymerization of ethylene and at least one other alpha-olefin, in the gas phase in a fluidized bed reactor, in the presence of a catalyst comprising chromium compounds associated with a granular support comprising a refractory oxide and activated by thermal treatment, which process is characterized in that the catalyst is used in the form of active particles of prepolymer, obtained by bringing the said catalyst in contact with ethylene, alone, or in a mixture with at least one higher alpha-olefin, in such a way that the prepolymer contains from 4.times.10.sup.-5 to 3 milligram atoms of chromium in the catalyst per gram.

Abstract: A method of manufacturing a polyolefin using a catalyst system of an ingredient (A) and ingredient (B), with ingredient A being obtained through successive reaction steps. Ingredient A is prepared by forming a mixture of (1) the combination of (a) metallic magnesium or an oxygen-containing organic compound of magnesium with (b) a mixture of a monohydroxylated organic compound and a polyhydroxylated organic compound, (2) oxygen-containing organic compounds of titanium and (3) at least one alpha-olefin having at least 4 cargon atoms, such as 1-hexene. The resulting solution is reacted in sequence with (4) at least one first halogenated aluminum compound, (5) at least one silicon compound and (6) at least one second halogenated aluminum compound. Ingredient B is an organometallic compound of metals from Group Ia, IIa, IIIa or IVa of the Periodic Table. The resulting free-flowing polyolefin is characterized by a large average particle size and small amount of fine particles.

Abstract: An olefin is polymerized or copolymerized under the presence of an olefin-polymerizing catalyst prepared from (A) a transition-metal compound or (A') a transition-metal compound loaded on a fine-particle carrier, said transition metal being selected from group IVB in the periodic table; (B) an aluminoxane; and (C) an organoaluminum compound represented by the general formula [I] or [II]:R.sup.1.sub.m Al(OR.sup.2).sub.3-m [I]R.sup.3.sub.n Al(OSiR.sup.4.sub.3).sub.3-n [II]wherein R.sup.1, R.sup.2, and R.sup.3 are selected from hydrocarbon radicals, R.sup.4 is selected from the group consisting of hydrocarbon, alkoxy, and aryloxy radicals, and m and n are positive numbers of 0<m<3 and 0<n<3. This catalyst has a significantly high polymerization activity, and the thus produced olefin polymer or copolymer has a narrow composition distribution, a high bulk density, and uniform grain size with little powdery product.

Abstract: The present invention relates to a process for polymerizing or copolymerizing alpha-olefins comprising, on the one hand, a prepolymerization stage by contacting one or more alpha-olefins with a Ziegler catalyst system consisting of a solid catalyst containing essentially atoms of halogen, magnesium and transition metal, and a co-catalyst consisting of an organomatellic compound, and, on the other hand, a polymerization or copolymerization stage in a gas phase process by means of a fluidized bed, by contacting one or more alpha-olefins with the prepolymer produced in the first stage, process characterized in that the alpha-olefin prepolymer and polymer or copolymer are in the form of a powder consisting of particules having specific values for the transition metal content and the mean diameter by mass, and characterized in that the particle size distribution of the prepolymer is narrow and easily controlled.

Abstract: The present invention relates to a process for the start up of polymerization or copolymerization in the gas phase by bringing the said alpha-olefins in contact under polymerization or copolymerization conditions in a fluidized bed and/or with mechanical stirring with a charge powder, in the presence of a catalyst system of the Ziegler-Natta type, this process being characterized in that the charge powder used is previously dehydrated and subjected to a treatment by bringing the said charge powder into contact with an organoaluminum compound for a period of at least five minutes, so that the polymerization or copolymerization starts up immediately after the contracting of the alpha-olefins with the charge powder in the presence of the catalyst system.

Abstract: The present invention relates to a process for starting up the polymerization of ethylene or copolymerization of ethylene and at least one other alpha-olefin by bringing ethylene and optionally at least one other alpha-olefin in contact under fluidized-bed polymerization or copolymerization conditions and/or stirred mechanically, with a charge powder in the presence of a catalyst comprising a chromium oxide compound associated with a granular support and activated by thermal treatment, this catalyst being used in the form of a prepolymer, this process being characterized in that the charge powder employed is previously subjected to a treatment by contacting the said charge powder with an organo-aluminium compound, in such a way that the polymerization or copolymerization starts up immediately after the contacting of the ethylene and optionally one other alpha-olefin with the charge powder in the presence of the prepolymer.

Abstract: A process for preparing a transition metal component for a catalyst system wherein a specified aluminosiloxane derivative is reacted with a monohalopenated, alkylated, or alkoxylated compound of magnesium and the reaction product is chlorinated and reacted with a transition metal; a catalyst system comprising such transition metal component and a cocatalyst selected from organometallic compounds of a metal of Groups I through III of the Periodic Table; and the process of synthesizing olefin homopolymers and copolymers utilizing such catalyst system.

Abstract: A process for the manufacture of a linear polyethylene with narrow molecular-weight distribution comprising polymerizing ethylene alone or a mixture of ethylene and an alpha-olefin in which ethylene represents at least about 70% by weight of the total monomers involved, in a gas-phase polymerization medium in the presence of a catalytic component containing at least one transition metal, magnesium, and a halogen, a co-catalyst comprising an alkylaluminum compound, and a monoether, the monoether having the general formula R'OR", wherein R' and R" are the same or different and each is a C.sub.1 to C.sub.8 linear or branched hydrocarbon radical or being a cyclic monoether with the oxygen forming a ring having 4 to 12 carbon atoms.

Abstract: A solid catalyst component for .alpha.-olefin polymerization containing as catalyst components at least titanium, magnesium and chlorine which are impregnated into an organic porous polymer carrier having a mean particle diameter of 5 to 1,000 .mu.m and a pore volume of 0.1 ml/g or above at a pore radius of 100 to 5,000 .ANG., a catalyst system comprising at least said solid catalyst component (A) and an organoaluminum compound (B), as well as a process for producing .alpha.-olefin polymers using said catalyst system.

Abstract: There is provided a process for polymerization of an .alpha.-olefin which comprises polymerizing an .alpha.-olefin in the presence of a catalyst which is a combination of a solid component (A), which is obtained by subjecting a composition (A.sub.O) comprising as the essential ingredients titanium, magnesium and a halogen to preliminary polymerizatoin of the .alpha.-olefin conducted in the presence of said composition in a slurry and an organoaluminum compound, and an organoaluminum compound (B), said preliminary polymerization being conducted in two steps: the first step wherein the concentration of said composition (A.sub.O) in the slurry is adjusted to 10-100 g/lit.-solvent and polymerization of the .alpha.-olefin is conducted at 30.degree. C. or lower so that the amount of a polymer produced is 0.001 to 1 g per gram of said composition and the second step wherein polymerization of the .alpha.-olefin is conducted at 60.degree. C.

Abstract: A catalyst component useful for (co)polymerizing ethylene under high temperatures and pressures comprising the reaction product obtained by treating a magnesium halide supported titanium halide precursor with Lewis acid, thoroughly washing the solid reaction product therefrom and prepolymerizing the washed solid product with an alpha-olefin having from 4-12 carbon atoms.

Abstract: A highly crystalline polypropylene is provided having:(A) (i) a melt flow rate (MFR) in the range of 0.1-200 g/10 minutes 230.degree. C. and (ii) an absorbance ratio determined by infrared absorption spectroscopy, IR-.rho., of wave-number 997 cm.sup.-1, A.sub.997, to wave-number 973 cm.sup.-1, A.sub.973, which satisfies the equation:IR-.tau..gtoreq.0.0203 log MFR+0.950; and(B) (i) an IR-.tau. value of at least 0.97 of a component deposited initially in an amount of 2 to 3% by weight from a dilute, slowly cooled and stirred xylene solution of the polypropylene and (ii) a ratio of the weight average molecular weight of the deposited component (M.sub.w1) to that of the polypropylene (M.sub.w0), M.sub.w1 /M.sub.w0, of at least 3.

Abstract: A process for (co)polymerizing alpha-olefins in the gas phase in a fluidized bed or mechanically stirred bed reactor using a Ziegler-Natta type catalyst or a heat activated chromium oxide/refractory oxide catalyst wherein the (co)polymerization is carried out in the presence of 0.005 to 0.2 weight %, based on the weight of the (co)polymer bed, of an inert pulverulent inorganic substance (e.g. silica) having a mean particle diameter between 0.5 and 20 microns. The process is capable of being operated at temperatures closer to the softening point of the produced polyolefin than in the absence of the pulverulent solid.

Abstract: A solid titanium catalyst component (A) of a catalyst system useful in the polymerization of olefins or copolymerization of two or more olefins or one or more olefins and a diene is prepared by contacting a liquid hydrocarbon solution of (i) a magnesium compound, such as magnesium chloride, with (ii) a liquid titanium compound, such as TiCl.sub.4, or a solution of a titanium compound in a hydrocarbon solvent, to form a solid product. The solid product is formed in the presence of (D) an electron donor, e.g. methyl formate, acetic acid, acetic anhydride, acetone, methyl ether, butyl Cellosolve, dimethyl carbonate, methyl silicate. The solid product is also contacted with a polycarboxylic acid ester, e.g. diethyl methylsuccinate. The polymerization or copolymerization of the olefin is carried out in the presence of the solid titanium catalyst (A) and (B) an organometallic compound of a Group I to III metal and (C) an organic silicon compound having an Si--O--C bond.

Abstract: The present invention relates to a gas phase process for the (co-)polymerization of alpha-olefins in a fluidized bed, by means of a catalyst system of the Ziegler-Natta type consisting of a catalyst (a) comprising magnesium, halogen and transition metal atoms and a cocatalyst (b) consisting of an organometallic compound. The catalyst system is (i) prepared in a granular form, either fixed on a granular support or converted into a prepolymer, (ii) then subjected to a treatment by a polymerization inhibiting agent in the absence of alpha-olefins, and then (iii) brought into contact with alpha-olefins under (co-)polymerization conditions in the fluidized bed, in the presence of a cocatalyst (c) consisting of an organometallic compound, identical or different from the cocatalyst (b).

Abstract: The present invention relates to a process for the polymerisation of ethylene or copolymerisation of ethylene and at least one other alpha-olefin, in the gas phase in a fluidised bed reactor, in the presence of a catalyst comprising chromium compounds associated with a granular support comprising a refractory oxide and activated by thermal treatment, which process is characterised in that the catalyst is used in the form of active particles of prepolymer, obtained by bringing the said catalyst in contact with ethylene, alone, or in a mixture with at least one higher alpha-olefin, in such a way that the prepolymer contains from 4.times.10.sup.-5 to 3 milligram atoms of chromium in the catalyst per gram.

Abstract: A method for producing an olefin polymer, which comprises polymerizing or copolymerizing olefins in the presence of a catalyst comprising:(A) a solid catalyst component obtained by thermally reacting (a.sub.1) a magnesium compound of the formula Mg(OR.sup.1).sub.n (OR.sup.2).sub.2-n wherein each of R.sup.1 and R.sup.2 which may be the same or different is an alkyl group, an aryl group or an aralkyl group, and n is 2.gtoreq.n.gtoreq.0, (a.sub.2) a titanium compound of the formula Ti(OR.sup.3).sub.4 wherein R.sup.3 is an alkyl group, an aryl group or an aralkyl group and (a.sub.3) a silicon compound of the formula Si(OR.sup.4).sub.4 wherein R.sup.4 is an alkyl group, an aryl group or an aralkyl group and contacting and treating (a) the resulting thermal reaction product with (b) a halogen-containing titanium compound and (c) an electron donative compound, and(B) an organometallic compound of a metal of Groups I-III of the Periodic Table.

Abstract: Finely divided ethane polymers are prepared using a Ziegler catalyst system consisting of (1) a titanium-containing catalyst component which has been obtained by (1.1) precipitation in an organic liquid comprising (1.1.1) a solution of titanium tetrachloride in a hydrocarbon, (1.1.2) a solution of a certain organoaluminum compound in a hydrocarbon and (1.1.3) an alpha-monoalkene, and (2) an aluminum-containing catalyst component. In this process, the component (1) used is a component where (1.

Abstract: The present invention relates to a process for the polymerisation or copolymerisation of alpha-olefins in the presence of a Ziegler-Natta catalyst system comprising on the one hand a catalyst solid comprising compounds of halogens, transition metals of Groups IV, V, VI of the Periodic Table of Elements, magnesium and optionally aluminum, free from a metal/carbon bond and on the other hand a catalyst consisting of organometallic compounds of metals of Group II or III of the said Table. This process is characterised in that before its use in polymerisation or copolymerisation, the catalyst solid is treated by water in a given quantity, this treatment making it possible to improve the conditions for obtaining polymers, particularly in a process of polymerisation or copolymerisation in the gas phase.

Abstract: Process for polymerising ethylene, or copolymerising ethylene with an alpha-olefin, in the gas phase in the presence of a prepolymer/catalyst composition, the catalyst being an activated chromium oxide supported on a refractory oxide. The prepolymer is treated to an extraction with a solution comprising inert hydrocarbon and an organometallic compound, for example an alkylaluminum, prior to being dried and introduced into the gas phase (co) polymerisation. Prepolymer thus treated has improved properties in the dry state, for example improved flow.

Abstract: The present invention relates to a gas fluidized bed process for the production of copolymers having a density between 0.900 and 0.935, which process comprises copolymerization of (a) ethylene, (b) propylene and/or 1-butene, and (c) alpha-olefins comprising from 5 to 8 carbon atoms in the gaseous state, in admixture with an inert gas and optionally with hydrogen, in the presence of a catalytic system comprising a cocatalyst consisting of at least 1 organo-metallic compound of a metal of groups II and III of the Periodic Table of Elements and a special solid catalyst.

Abstract: A process for polymerizing or copolymerizing a member of the group consisting of an alpha olefin or mixtures thereof, consisting of the steps of:polymerizing an alpha olefin in a polymerization reactor using a polymerization catalyst, a cocatalyst, and an amount of hydrogen adjusted for molecular weight control as measured by melt flow;rapidly changing the melt flow of the polymerized alpha olefin from high to low melt flow by reacting a portion of the unreacted hydrogen in the reactor with a quantity of the alpha olefin present therein by interaction with a hydrogenation catalyst; andremoving the hydrogenation catalyst from the reactor through continuous exchange of the reactor contents.

Abstract: Ethylene is polymerized using a Ziegler catalyst system consisting of (1) a titanium catalyst component and (2) an aluminum catalyst component, the component (1) used being the product (VI) which is obtained by a method in which (1.1) first (1.1.1) a carrier (I) and (1.1.2) a solution (II) of (IIa) a solvent, (IIb) a titanium trichloride and (IIc) magnesium chloride are combined with formation of a dispersion (III) and the latter is evaporated down with formation of an intermediate (IV), and (1.2) then (1.2.2) the intermediate (IV) obtained from (1.1), and (1.2.2) an aluminum component (V) consisting of (1.2.2.1) a complex of a certain oxacycloalkane and a certain aluminum compound and (1.2.2.2) if necessary, a certain free aluminum compound are combined, the resulting product (VI) being the catalyst component (1). In this process, a component (1) is employed which has been prepared using, in (1.1) under (1.1.

Abstract: A packaging transparent propylene copolymer film stretched in at least one direction, which consists of a copolymer of propylene and an .alpha.-olefin having 4 or more carbon atoms or a copolymer of propylene, an .alpha.-olefin having 4 or more carbon atoms and ethylene. The copolymer satisfies the following conditions;(1) the content of the .alpha.-olefin having 4 or more carbon atoms in the copolymer is 8-25 mole %,(2) the content of ethylene in the copolymer is 5 mole % or less,(3) the content of a cold xylene-soluble portion in the copolymer is 15-50% by weight, and(4) the flexural modulus of the copolymer is 2,500-7,000 kg/cm.sup.2.

Abstract: An ultra-high molecular weight polyethylene powder easily soluble in organic solvents and suitable for use in the preparation of fibers or films having a high strength and a high elastic modulus, said polyethylene powder having an intrinsic viscosity in the range of 5 to 30 dl/g in decalin at 135.degree. C. and being obtained by at least two-step polymerization reactions which are:a first step of polymerizing ethylene in the absence of hydrogen or at a reduced hydrogen concentration, using a catalyst containing a solid catalyst component and an organometallic compound, said solid catalyst component containing at least magnesium and titanium and/or vanadium, to produce 50-99.5 parts by weight, based on 100 parts by weight of a final polyethylene product, of polyethylene having an intrinsic viscosity of 12 to 32 dl/g in decalin at 135.degree. C.; anda second step of polymerizing ethylene at a higher hydrogen concentration that in said first step to produce 50-0.5 parts by weight of polyethylene.

Abstract: The present invention relates to a process for the polymerization of alpha-olefins in the gas phase in the presence of a Ziegler-Natta catalyst system consisting of a catalyst comprising atoms of halogen, magnesium and a transition metal, and cocatalysts based on an organometallic compound of a metal of Groups II or III of the Periodic Table of Elements, this catalyst system being previously converted into a prepolymer or a catalyst supported on a granular substance. This process is characterized in that the polymerization in the gas phase is carried out by contacting one or more alpha-olefins, on the one hand with the prepolymer or the supported catalyst system comprising an organometallic compound (a) which is only slightly volatile as cocatalyst, and on the other hand another cocatalyst consisting of an organometallic compound (b) which is relatively volatile, in such a way that the total quantity of cocatalyst employed is relatively small.

Abstract: The present invention relates to a process for polymerizing or copolymerizing alpha-olefins comprising, on the one hand, a prepolymerization stage by contacting one or more alpha-olefins with a Ziegler catalyst system consisting of a solid catalyst containing essentially atoms of halogen, magnesium and transition metal, and a co-catalyst consisting of an organomatellic compound, and, on the other hand, a polymerization or copolymerization stage in a gas phase process by means of a fluidized bed, by contacting one or more alpha-olefins with the prepolymer produced in the first stage, process characterized in that the alpha-olefin prepolymer and polymer or copolymer are in the form of a powder consisting of particles having specific values for the transition metal content and the mean diameter by mass, and characterized in that the particle size distribution of the prepolymer is narrow and easily controlled.

Abstract: A catalyst, a process of forming the catalyst, and polymerizing at least one alpha-olefin with the catalyst, said catalyst produced by precipitating a composition from a solution of a metal halide, for example, magnesium dihalide, and a transition metal compound, for example, titanium tetraalkoxide, in the presence of a particulate diluent, for example, polymeric fibrils, with an agent selected from among specified organometallic compounds, metal halides and oxygen-containing metal halides, hydrogen halides and organic acid halides. The composition is preferably further treated with a halide ion exchanging source, for example, titanium tetrahalide to form a particularly active catalyst. The catalyst is preferably used in combination with a cocatalyst comprising a metal hydride of organometallic compound selected from an element of Periodic Groups IA, IIA and IIIA.

Abstract: Finely divided ethene polymers are prepared by means of a Ziegler catalyst system composed of (1) a titanium-containing catalyst component obtained by precipitation in an organic liquid from (1.1) a solution of titanium tetrachloride in a hydrocarbon, (1.2) a solution of a certain organoaluminum compound in a hydrocarbon, and a catalyst component which contains (1.

Abstract: Ethylene is homopolymerized or copolymerized with another olefin monomer in the presence of a catalyst system comprising organo metal cocatalyst and a titanium-containing catalyst component, said titanium-containing catalyst component being obtained by reacting together a porous particulate material, an organic magnesium compound, a halogen or interhalogen compound and titanium tetrachloride.

Abstract: Copolymerization of ethylene and a C.sub.3 -C.sub.20 alpha-monoolefin at high temperature gives a low density polyethylene having a density of between 0.91 and 0.93 g/cc. The copolymerizations are accomplished with a catalyst made by co-comminuting an anhydrous magnesium halide, an anhydrous aluminum halide, a titanium compound, and at least one electron donor, and a cocatalyst comprising a synergistic mixture of an alkyl aluminum chloride and an oxygen-containing aluminum compound having oxygen attached to at least one aluminum valence.

Abstract: A first reactant selected from arylsilanol, hydrocarbyl amine, hydrocarbylphosphine oxide, and hydrocarbyloxyphosphite is combined with a second reactant selected from halogenated transition metal compound and an organometal compound to form a product which is catalytically active for olefin polymerization after optionally first having been deposited on a particulate diluent.

Abstract: A vanadium-containing catalyst component useful for the polymerization of olefins to polyolefins having a high molecular weight and a broad molecular weight distribution comprising polymerizing the polyolefins in the presence of a catalyst comprising (A) a vanadium-containing catalyst component obtained by contacting an inert support material with a dihydrocarbyl magnesium compound, optionally an oxygen-containing compound, a vanadium compound, a Group III metal halide, and (B) an aluminum alkyl cocatalyst.

Abstract: A highly active catalyst for olefin polymerization, which is resistant to catalyst poisons contained in olefins as polymerization raw material and according to which the percentage of amorphous polymer formed is small, is provided, which catalyst is obtained byreacting a reaction product (I) of an organoaluminum compound with an electron donor, with TiCl.sub.4,further reacting the resulting solid product (II) with an electron donor and an electron acceptor,mixing the resulting solid product (III) with an organoaluminum compound in an inert solvent,keeping the resulting catalyst dispersion at 0.degree. to 70.degree. C., andhaving a small amount of an .alpha.-olefin and an extremely small amount of carbonyl sulfide slowly absorbed in the dispersion kept as above, to thereby subject the dispersion to a preliminary polymerization.

Abstract: A process for producing an olefin polymer which comprises the homopolymerizing or copolymerizing an olefin in the presence of a catalyst system composed of an organoaluminum compound and a hydrocarbyloxy group-containing solid catalyst component which is prepared byreducing a titanium compound represented by the general formula Ti(OR.sup.1).sub.n X.sub.4-n, wherein R.sup.1 is a C.sub.1 -C.sub.20 hydrocarbon radical, X is halogen, and n is a number defined as 0<n.ltoreq.4, with an organoaluminum compound represented by the general formula AlR.sup.2.sub.m Y.sub.3-m, wherein R.sup.2 is a C.sub.1 -C.sub.20 hydrocarbon radical, Y is halogen, and m is a number defined as 1.ltoreq.m.ltoreq.3,subjecting the reduction product, which is a hydrocarbyloxy group-containing solid insoluble in hydrocarbon solvents, to a prelimary ethylene polymerization treatment, andtreating the resultant solid in a state of slurry in a hydrocarbon solvent with an ether compound and titanium tetrachloride at a temperature of 30.degree.

Abstract: A suspension which comprises an inert liquid medium, a solid material, a transition metal compound and an agglomeration aid is dried using a spray-drying technique. The spray-drying is effected under conditions of temperature and pressure which are such as to cause evaporation of the liquid medium. The solid material is preferably in a finely-divided form and may consist essentially of a transition metal compound or may be a transition metal compound which is supported on a suitable solid inert matrix material. Alternatively, a suspension of a solid support material in a solution of a transition metal compound may be used. The agglomeration aid may be polystyrene dissolved in the inert liquid medium. The dried solid is obtained as an agglomerated solid which can be mixed with an organic compound of a non-transition metal to give an olefin polymerization catalyst system.

Abstract: .alpha.-Olefins are polymerized in the presence of Ziegler-Natta catalysts which are polymer supported compounds or complexes of elements of the d-block transition metals, lanthanide or actinide series. An example of the polymer support is chloromethylated polystyrene-divinyl benzene copolymer covalently bonded to catechol. An example of the compound or complex of an element of the transition metal, lanthanide or actinide series is that which results when catechol which is covalently bonded to the polymer is contacted with titanium tetraisopropoxide.

Abstract: A catalyst system for use in the polymerization of ethylene under high pressure and temperature containing an alkyl-aluminum or alkylsiloxalane activator and a compound of the formula:(TiCla) (MgCL.sub.2).sub.y (AlCl.sub.3)z (RMgCl).sub.bin whicha is from 2 to 3;y is 2 or more;z is from 0 to 1/3;b is from 0 to 1; andR is an aliphatic or aromatic hydrocarbon radical.

Abstract: A process for producing .alpha.-olefin polymers is proposed wherein the catalyst prepared and used therein is superior in the shelf stability and heat stability. The process comprises reacting TiCl.sub.4 with a reaction product (I) of an organoaluminum compound with an electron donor to obtain a solid product (II), which is then subjected to polymerization treatment with an .alpha.-olefin, and further reacted with an electron donor and an electron acceptor to obtain a solid product (III), which is then combined with an organoaluminum compound, to obtain a catalyst, in the presence of which .alpha.-olefin(s) are polymerized. The catalyst can be further preactivated with an .alpha.-olefin in advance of its use for the polymerization.