Abstract: A titanium trichloride catalyst component containing a minor amount of prepolymerized alpha-olefin and useful in the polymerization of alpha-olefins is produced by reducing titanium tetrachloride with an organoaluminum compound at low temperatures and then treating the resulting reduced solids product with about 1 to 1,000 wt. % alpha-olefin so as to obtain a prepolymerized titanium trichloride reduced solid. The prepolymerized reduced solid can thereafter be activate to a highly active prepolymerized titanium trichloride by treating the prepolymerized reduced solid with a halogenated hydrocarbon and a Lewis base complexing agent or titanium tetrachloride and a Lewis base complexing agent. The prepolymerized reduced solid and the prepolymerized activated titanium trichloride manifests substantially no evidence of friability upon being subjected to mechanical shearing forces.

Abstract: A process for the preparation of ethylene-propylene impact copolymers at improved catalyst productivity rates involving the formation of a propylene prepolymer by polymerization of propylene in liquid phase in the presence of a catalyst system containing titanium halide supported on magnesium halide and aluminum alkyl complexed with an electron donor. Ethylene and propylene are block polymerized onto the prepolymer in a vapor phase reaction zone in the presence of a second catalyst system comprising a solution of a C.sub.5 -C.sub.9 polyalpha-monoolefin/catalyst/diluent.

Abstract: A process for producing .alpha.-olefin polymers having high crystallinity and good particle form, with a high yield is provided. The polymerization therefor is carried out in the presence of a preactivated catalyst suitable particularly to gas phase polymerization or gas phase polymerization following slurry or bulk polymerization.The catalyst is prepared by reacting a reduction solid prepared by reducing TiCl.sub.4 with an organoaluminum compound, with an electron donor and an electron acceptor to obtain a solid product, andcombining this solid product with an organoaluminum compound, an .alpha.-olefin and a reaction product of an organoaluminum compound with an electron donor.

Abstract: The present invention relates to catalysts which can be used for the polymerization and copolymerization of propylene with other alpha-olefins, characterized in that they comprise a support containing essentially magnesium chloride and possibly a chlorinated aluminium derivative, and occurring in the form of spheroidal particles having a mean diameter by mass comprised between 10 and 100 microns and a particle size distribution such that the ratio of the mean diameter by mass to the mean diameter by number is less than or equal to 3, which support has been treated by an electron donor compound chosen from among the aromatic ethers and aromatic acid esters and which when impregnated with titanium tetrachloride comprises 0.5 to 3% of atoms of titanium per atom of magnesium, and process for utilizing the said catalyst.

Abstract: A process for producing terpolymers of propylene (as a main monomer), ethylene and another .alpha.-olefin having superior and well-balanced physical properties, almost without forming soluble polymer is provided.This process is characterized by preliminarily activating a catalyst consisting of a titanium trichloride composition and a specified organoaluminum halide, with a small amount of an .alpha.-olefin of 2 to 12 carbon atoms, a trialkylaluminum and an aromatic ester, and copolymerizing specified amounts of propylene, ethylene and an .alpha.-olefin of 4 to 12 carbon atoms in the presence of the preliminarily activated catalyst obtained above.

Abstract: Ethylene copolymers having a density of about 0.91 to 0.94 and a melt flow ratio of about .gtoreq.26 to .ltoreq.40 are readily produced in a low pressure gas phase process at a productivity of .gtoreq.500,000 pounds of polymer per pound of Ti with a catalyst formed from selected organo aluminum compounds and a composition prepared by copulverizing magnesium dihalide with a complex obtained by contacting a titanium compound of the structure Ti(OR).sub.a X.sub.b with an ether, ester, ketone or amine,wherein R is a C.sub.1 to C.sub.14 aliphatic or aromatic hydrocarbon radical, or COR' where R' is a C.sub.1 to C.sub.14 aliphatic or aromatic hydrocarbon radical,X is Cl, Br, I or mixtures thereof, a is 0 or 1, b is 2 to 4 inclusive and a+b=3 or 4.

Abstract: A polymer-supported constituent for olefin polymerization catalyst obtained by: mixing in organic solution a chlorine-containing organic polymer and a magnesium compound, removing the solvent, and reacting the resulting magnesium-modified polymer with a titanium halide. An olefin polymerization catalyst is formed by mixing such a polymer-supported constituent with an appropriate organo-metallic compound and optionally also an appropriate selectivity control agent.

Abstract: A titanium trichloride catalytic component and a method for homo- or co-polymerization of an .alpha.-olefin. In separating a titanium trichloride catalytic component from a solution prepared by dissolving titanium tetrachloride, an organic ether compound and an organo-aluminum compound in a solvent, the above stated solvent is a mixed solvent prepared by allowing 20.about.70% by volume of an aromatic hydrocarbon halide to be concomitant with a saturated aliphatic hydrocarbon and/or an alicyclic hydrocarbon in the presence of an olefin; the organo-aluminum compound, the titanium tetrachloride and the organic ether compound are added to the mixed solvent at a solvent temperature not exceeding 55.degree. C.; then, the solvent temperature is raised to a temperature between 45.degree. and 150.degree. C.

Abstract: This invention reveals a very useful process for producing polybutadiene composed essentially of syndiotactic 1,2-polybutadiene in tetrahydrofuran comprising polymerizing 1,3-butadiene in said tetrahydrofuran in the presence of (1) a catalyst composition microencapsulated in a polyene product which contains (a) at least one cobalt compound selected from the group consisting of (i) .beta.-diketone complexes of cobalt, (ii) .beta.-keto acid ester complexes of cobalt, (iii) cobalt salts of organic carboxylic acids having 6 to 15 carbon atoms, and (iv) complexes of halogenated cobalt compounds of the formula CoX.sub.n, wherein X represents a halogen atom and n represents 2 or 3, with an organic compound selected from the group consisting of tertiary amines, alcohols, tertiary phosphines, ketones and N,N-dialkylamides, and (b) at least one organoaluminum compound of the formula AlR.sub.3, wherein R represents a hydrocarbon radical of 1 to 6 carbon atoms; and (2) carbon disulfide.

Abstract: A suspension which comprises an inert liquid medium, a solid material, and a transition metal compound 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. The solid material 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 dried solid is obtained as an agglomerate. The agglomerated solid can be mixed with an organic compound of a non-transition metal to give an olefin polymerization catalyst system.

Abstract: A process for producing highly crystalline .alpha.-olefin polymers of good particle form with high yield is provided, which comprises polymerizing .alpha.-olefin in the presence of a preactivated catalyst obtained by reacting a reaction product (I) of organoaluminum compound (A.sub.1) with electron donor (B.sub.1), with TiCl.sub.4 to obtain a solid product (II); further reacting (II) with electron donor (B.sub.2) and electron acceptor to obtain a solid product (III); during or/and after the reaction step for obtaining (II) or/and during or/and after the reaction step for obtaining (III), subjecting (II) or (III), to polymerization treatment with .alpha.-olefin; and combining the resulting final solid product with organo-aluminum compound (A.sub.2) and a reaction product (G) of organo-aluminum compound (A.sub.3) with electron donor (B.sub.3) to obtain a preactivated catalyst; and preferably, in this combination, further subjecting a part or the total of the catalyst to polymerization treatment with .alpha.

Abstract: Poly-.alpha.-olefin, for example, polypropylene, is produced by subjecting a feed containing an .alpha.-olefin having 3 or more carbon atoms, to a preliminary polymerization at 40.degree. C. or less in the presence of a catalyst which comprises (A) a solid catalytic ingredient prepared (a) by reacting a Grignard compound of the formula, R.sup.3 MgX wherein R.sup.3 =C.sub.1-8 alkyl and X=halogen, with a reaction product of an aluminium halide with an organic silicon compound of the formula, R.sub.n.sup.1 Si(OR.sup.2).sub.4-n, wherein R.sup.1 =C.sub.1-8 alkyl or phenyl, R.sup.2 =C.sub.1-8 alkyl, n=0, or 1 to 3, (b) bringing the resultant solid carrier into a first contact with titanium tetrahalide, (c) treating the resultant titanium-containing solid product with an organic acid ester, and, finally, (d) bringing the treated solid product into a second contact with titanium tetrahalide; (B) another catalytic ingredient consisting of a trialkyl aluminium of the formula, AlR.sub.3.sup.4 wherein R.sup.4 =C.sub.

Abstract: A high activity supported catalytic component obtained by pulverizing together (a) an anhydrous magnesium halide and (b) a titanium compound in the concomitant presence of 0.1 to 20 wt. % of (c) a liquid aromatic hydrocarbon and/or a liquid aromatic hydrocarbon halide, within the supported catalytic component, at temperature between 0.degree. and 100.degree. C. at which the liquid aromatic hydrocarbon and/or the liquid aromatic hydrocarbon halide remains in a liquid state throughout the whole range of temperature during the pulverization; and a method in which .alpha.-olefin is homo- or co-polymerized in the presence of a catalytic system comprising the high activity supported catalytic component, an organo-aluminum compound and an electron donor.

Abstract: A transition metal compound and a metal halide compound are chemically combined to form a composition of matter. The composition of matter is mixed with a precipitating agent to form an active olefin polymerization catalyst. The catalyst can be further treated with a halide ion exchanging source to form an active olefin polymerization catalyst. Prepolymer is deposited on the catalyst(s) in an amount effective to reduce polymer fines when the catalyst(s) are used in polymerization processes.

Abstract: A transition metal compound and a metal halide compound are chemically combined to form a composition of matter. The composition of matter is rapidly mixed with a precipitating agent to form an active olefin polymerization catalyst.

Abstract: The invention relates to a method for preparing polymers of ethylene and propylene, or of copolymers of ethylene and alpha olefins such as propylene 1-butene and 1-hexene or alpha omega dienes such as alpha omega octadiene, respectively, by polymerization within a temperature range from -80.degree. to 150.degree. C. in the presence of a halogen free Ziegler type catalyst system consisting of a cyclopentadienyl compound containing a transition metal and of an aluminum alkyl compound, whereby the polymerization is made in the presence of catalyst system consisting of the following components:(1) a compound containing a transition metal and having the general formula (cyclopentadienyl).sub.n MeY.sub.n, in which n is an integer from 1 to 4, Me is a transition metal, preferably zirconium, and Y being selected from the group of hydrogen, a C.sub.1 -C.sub.5 alkyl group or C.sub.1 -C.sub.5 metal alkyl group or of a compound of the following general formula ##STR1## in which R is a C.sub.1 -C.sub.5 alkyl group or C.

Abstract: A novel method of polymerizing and copolymerizing 1-olefins utilizing a catalyst active in the presence of an organometallic co-catalyst is disclosed. The catalyst is prepared by mixing an alkyl aluminum halide, a dialkyl magnesium compound and a reducible titanium compound of the formula Ti(OR).sub.n X.sub.4-n where R is an alkyl group, preferably of 1-6 carbon atoms, X is a halogen atom, and n is an integer between 0 and 4, inclusive, in the presence of a solvent and a particulate organic polymer whereby a reaction product is formed on the particles, and evaporating the solvent.

Abstract: A propylene polymerization catalyst comprises (a) a titanium-containing component formed by reducing titanium tetrachloride with an aluminum alkyl, optionally contacting the resulting reduced solid with a pretreatment amount of alpha-olefin monomer under polymerization conditions, and reacting the resulting product with a Lewis base complexing agent and additional titanium tetrachloride, and (b) an alkyl aluminum halide having a halogen/aluminum atomic ratio between 0.89 and 0.98 and preferably between 0.92 and 0.98.

Abstract: A supported titanium catalyst component is produced by cogrinding an organo aluminum catalyst component with a supported titanium (IV) halide on a magnesium halide. The resulting supported titanium halide catalyst component, when employed with an organo aluminum catalyst component to form a catalyst system is highly useful for the stereoregular polymerization of .alpha.-olefins as well as the copolymerization of .alpha.-olefins.

Abstract: A process for producing .alpha.-olefin polymers is provided, which comprises: reacting an organoaluminum compound with an electron donor in a specified ratio in a solvent at a specified temperature to obtain a solid product (I); reacting solid product (I) with TiCl.sub.4 at a specified temperature in a specified ratio of Al/Ti and then removing a liquid portion from the resulting material followed by washing to obtain a solid product (II) having no free TiCl.sub.4 ; reacting solid product (II) with an electron donor and an electron acceptor in a specified ratio at a specified temperature to obtain a solid product (III); and polymerizing .alpha.-olefin(s) in the presence of a catalyst comprising a combination of solid product (III) with an organoaluminum compound. This process provides a catalyst having a high storing and thermal stability and a polymer having a uniform particle size.

Abstract: A process for producing .alpha.-olefin polymers is provided which comprises:reacting an organoaluminum compound (A.sub.1) with an electron donor (B.sub.1) to obtain a reaction product (I);reacting (I) with TiCl.sub.4 to obtain a solid product (II);reacting (II) with an electron donor (B.sub.2) and an electron acceptor to obtain a solid product (III);combining (III) with an organoaluminum compound (A.sub.2) and a reaction product (G) of an organoaluminum (A.sub.3) with an electron donor (B.sub.3) ((III), (A.sub.2) and (G) being referred to as catalyst components), and in this combination, subjecting a part or the whole of the catalyst components to polymerization treatment with an .alpha.-olefin at least in the presence of (III) and said (A.sub.2) to obtain a preliminarily activated catalyst;andpolymerizing an .alpha.-olefin in the presence of the catalyst.

Abstract: A method for producing crystalline copolymers of propylene (major component), ethylene and an .alpha.-olefin having 4 to 12 carbon atoms, superior in any of various practical physical properties such as cold-resistance, transparency, heat-seal temperature, percentage shrinkage, etc. is provided, wherein a catalyst solution obtained by mixing together a titanium trichloride composition (obtained by mixing and milling a titanium trichloride with a mixed reaction product of TiCl.sub.4 with an ether), a dialkylaluminum halide, an electron-donor compound and an inert solvent, is activated in advance of copolymerization, by feeding propylene into the solution under specified feeding conditions, and copolymerization is carried out by feeding propylene and said .alpha.-olefin simultaneously and continuously, while feeding ethylene intermittently into the gas phase part of the polymerization zone containing the solution.

Abstract: A process for producing .alpha.-olefins is provided which comprises:milling (A) a trivalent metal halide together with (B) a divalent metal compound, in a specified ratio of (A) to (B), and reacting them to obtain a solid product (I);reacting with this product (I), (C) an electron donor and (D) an electron acceptor, (C) and (D) being respectively reacted once or more up to ten times, and TiCl.sub.4 being employed as the electron acceptor at least once, to obtain a solid product (II);combining with this product (II), (E) a trialkylaluminum and (G) a reaction product of an electron donor with an electron acceptor, and in this combination, subjecting a part or the whole of the catalyst components (product (II), (E) and (G)) to polymerization treatment by reacting (F) an .alpha.-olefin at least in the presence of the product (II) and trialkylaluminum, to obtain a preliminarily activated catalyst; andpolymerizing an .alpha.-olefin in the presence of this catalyst.

Abstract: A catalyst formed from selected organo aluminum compounds and a precursor composition of the formulaMg.sub.m Ti.sub.l (OR).sub.n X.sub.p [ED].sub.qwherein ED is a selected electron donor compoundm is .gtoreq.0.5 to .ltoreq.56n is 0, 1 or 2p is .ltoreq.2 to .gtoreq.116q is .gtoreq.2 to .ltoreq.85R is a C.sub.1 to C.sub.14 aliphatic or aromatic hydrocarbon radical, or COR' wherein R' is a C.sub.1 to C.sub.14 aliphatic or aromatic hydrocarbon radical, andX is selected from the group consisting of Cl, Br, I or mixtures thereof,which catalyst is in particulate form and impregnated in a porous inert carrier material.A process for preparing such catalyst.A process for using said catalyst to readily prepare ethylene copolymers having a density of about .gtoreq.0.91 to .ltoreq.0.94 and a melt flow ratio of .gtoreq.22 to .ltoreq.32 in a low pressure gas phase process at a productivity of .gtoreq.50,000 pounds of polymer per pound of Ti.Novel polymers and molded articles are prepared.

Abstract: A catalyst composition formed from selected organoaluminum compounds and a precursor composition of the formulaMg.sub.m Ti.sub.1 (OR).sub.n X.sub.p [ED].sub.q [Filler].sub.rwhereinED is a selected electron donor compoundR is a C.sub.1 to C.sub.14, aliphatic or aromatic hydrocarbon radical, or COR' wherein R' is a C.sub.1 to C.sub.14 aliphatic or aromatic hydrocarbon radical, X is Cl, Br, I, or mixtures thereof, Filler is an inert organic or inorganic compound, and, based on the total weight of such compositionm is .gtoreq.0.5 to .ltoreq.56n is 0 or 1p is .gtoreq.6 to .ltoreq.116q is .gtoreq.2 to .ltoreq.5r has a value such that the percent filler is from about 10 to about 95 weight percent based on the total weight of the precursor composition. A process for preparing such precursor composition by spray drying it from a slurry or solution in said electron donor compound, using atomization. A process for using said catalyst to readily prepare ethylene polymers having a density of about .gtoreq.0.91 to .ltoreq.

Abstract: Process for polymerizing alpha-olefins employing a pretreated catalyst comprising an organopolylithiumaluminum compound prepared by reacting lithium compounds selected from the group consisting of lithium hydride and lithium alkyl with at least one aluminum compound selected from the group consisting of aluminum trialkyl and dialkyl aluminum hydride, an alkyl compound selected from the group consisting of lithium alkyl, aluminum trialkyl and dialkyl aluminum hydride and the alpha form of TiCl.sub.3. This catalyst is pretreated by initially polymerizing alpha-olefins with the catalyst under slurry polymerization conditions to form a small amount of prepolymer. The catalyst and small amount of prepolymer is then used to polymerize alpha-olefins subsequently under solution conditions in solution commercial polymerization processes operated at temperatures above 140.degree. C. over extended periods of time.

Abstract: Storage stability of Ziegler-type catalysts for .alpha.-olefin polymerization and having a specific surface greater than 75 m.sup.2 /g is improved by treating the catalysts with a preactivator which is an organic compound of a metal of one of Groups Ia, IIa, IIb and IIIa of the Periodic Table.CROSS-REFERENCE TO RELATED APPLICATIONThe invention described herein is directly related to that described in copending Application Ser. No. 236,407, filed Mar. 21st, 1972. The entire text of that application is incorporated herein by reference.BACKGROUND OF THE INVENTIONZiegler-type microporous catalytic complexes having a specific surface area greater than 75 m.sup.2 /g and useful for the polymerization of .alpha.-olefins are prepared by (a) reducing TiCl.sub.4 by means of an aluminum alkyl; (a') optionally isolating the reduced solid, based on TiCl.sub.

Abstract: A solid titanium trichloride, produced by precipitation from a homogeneous solution or mixture with an ether, is treated by prepolymerization with propylene at a partial pressure of less than 1 kg/cm.sup.2. The pretreated titanium trichloride containing a propylene polymer is then admixed with an organoaluminum compound and the admixture is used as a catalyst in the polymerization of propylene.

Abstract: In producing a low density polyethylene by a slurry copolymerization of ethylene and an .alpha.-olefin with use of a catalyst consisting of a magnesium compound-supported titanium and/or vanadium compound and an organoaluminum compound, a certain amount of ethylene is subject to a pre-polymerization in the presence of said catalyst prior to the copolymerization. Successively, the slurry copolymerization of ethylene and an .alpha.-olefin is effected in a low-boiling diluent to obtain a low density polyethylene of 0.925-0.950 in density, covering various grades in a wide range.

Abstract: Ethylene is polymerized in a gaseous phase and in contact with a Ziegler/Natta type solid catalyst capable of producing polyethylene in the form of granules having an easily controllable and homogeneous granulometric size, the polymerization being conducted in a tubular reactor in which the catalyst and the polymer granules which are formed are carried along the reactor by the flow of the gas.

Abstract: Polymerization of ethylene or .alpha.-olefins using a catalyst comprising a titanium component obtained by copulverizing the starting titanium component of Ziegler catalysts and organoaluminum compound with a small amount of ethylene or .alpha.-olefins, and an organoaluminum component. The titanium catalyst component can be modified by subjecting the copulverized titanium component to a contact with an inert organic solvent or its mixture with a modifier (1) an oxygen-, sulphur-, phosphor-, nitrogen- or silicon- containing organic compound, (2) a combination of such an organic compound and an aluminum halide, (3) an organoaluminum compound or (4) a Lewis acid.

Abstract: A novel method is disclosed for the preparation of polyphenylene oxides by the oxidative coupling of phenolic monomers which is based on the use of a manganese-vinyl resin complex as a catalyst.

Abstract: A catalyst for the (co)polymerization of ethylene, .alpha.-olefines, conjugated and non-conjugated dienes, a method of preparation, and a mode of using same. The catalyst contains from 0.1 to 50 wt.% of a compound of a transition metal of the IV-VIII Groups chemically combined and distributed over the surface and within the volume of a rubber-like polymeric carrier containing from 1 to 50 wt.% of electron-donor and/or electron-acceptor groups and is in the form of a gel which is swellable, but insoluble in the reaction medium.A co-catalyst comprising an organic compound of a metal of Groups I-III is employed chemically combined and/or non-combined with the catalyst.The catalyst is prepared by mixing the metal compound with said carrier swollen or dissolved in a solvent, and by extracting the resulting compound with a solvent.(Co)polymerization is effected in a solvent such as a hydrocarbon or a hologenated hydrocarbon derivative at a temperature not exceeding 200.degree. C.

Abstract: A random copolymer consisting essentially of 40 to 90 mole% of propylene and 60 to 10 mole% of 1-butene, and having (A) a boiling n-heptane-insoluble content of not more than 5% by weight based on the weight of the copolymer, (B) a boiling methyl acetate-soluble content of not more than 2% by weight based on the weight of the copolymer, (C) a melting point, determined by differential thermal analysis, of 40 to 140.degree. C., (D) an intrinsic viscosity, determined in decalin at 135.degree. C., of 0.5 to 6 dl/g, (E) an elongation at break, measured by JIS K6301, of at least 300%, (F) a tensile strength at break, measured by JIS K6301, of at least 50 kg/cm.sup.2, and (G) a haze, measured by JIS K6714, of not more than 40%.

Abstract: Gas-phase polymerization of an .alpha.-olefin, especially propylene, in a stirred or fluidized bed of substantially uniform and approximately spherical carrier particles of an .alpha.-olefin polymer of diameter 100-500 .mu.m, using a catalyst comprising an organo-metallic compound and a solid transition metal compound which has a particle size of less than 5 .mu.m, produces a propylene polymer having unexpectedly good powder flow characteristics. The transition metal compound is conveniently a titanium trichloride-containing material which has been treated with a dialkyl ether solution.

Abstract: A process for the polymerization of vinyl halides and/or vinylidene halides which comprising contacting the vinyl halide and/or vinylidene halide in gaseous form with a catalyst composition comprising(a) at least one compound of a transition metal of Groups IVA to VIA of the Periodic Table of the Elements, as hereinbefore defined, and(b) at least one compound having the structure ##STR1## WHERE M is aluminum or zinc, n and m each is an integer not greater than one less than the valency of M, at least one of the groups R is a hydrocarbon group, R.sup.1 is hydrogen or a hydrocarbon group, and X is hydrogen or a monovalent organic group.

Abstract: A novel method is disclosed for the preparation of polyphenylene oxides by the oxidative coupling of phenolic monomers which is based on the use of a manganese-vinyl resin complex as a catalyst.

Abstract: Alpha-olefins C.sub.3 -C.sub.6 are polymerized stereospecifically with the aid of catalysts obtained by mixing(a) a catalyst-forming component which is an addition and/or substitution product of an electron-donor compound (or a Lewis base) with an aluminum trialkyl, or an addition product of an electron-donor compound with an alkyl aluminum compound containing two or more Al - atoms bound to each other through an oxygen or nitrogen atom with(b) a supported catalyst-forming component which is the product obtained by contacting a titanium compound, preferably in the form of an addition product with an electron donor, with a carrier which is a mixture of an active anhydrous Mg or Mn dihalide and a solid organic material which is inert to all other components of the catalyst including the Mg or Mn dihalide carrier.

Abstract: Easily pourable polyolefin granules are obtained by polymerizing an olefin in the presence of a polymerization catalyst system comprising a compound having a main catalyst component supported on a spheroidal particle, 1 to 1,000 .mu. in diameter, of a high molecular compound used as a carrier, and an organometallic compound under a pressure of 100 kg/cm.sup.2 or less and at a temperature lower than both of the melting points of the resulting polymer and the said high molecular compound used as a carrier. The granule diameter of the said polyolefin can be controlled very easily by changing the particle size of the high molecular compound used as a carrier, the loading rate of the main catalyst component on the high molecular compound used as a carrier, or the catalyst efficiency. The granule size distrubution can be controlled by controlling the particle size distribution of the high molecular compound used as a carrier. The polyolefin granules obtained have a bulk density of 0.4 to 0.

Abstract: Polymerization of a mono-.alpha.-olefine monomer is effected by contacting the gaseous monomer with a solid phase comprising polymer and catalyst at a pressure and temperature which are such that the temperature is in the range from tp + 0.1.degree. C up to tp + 5.0.degree. C, where tp is the temperature at which the monomer condenses at a pressure which is equal to the monomer partial pressure within the polymerization vessel.

Abstract: The polymerization of olefins to form polymers having a molecular weight greater than 50,000 wherein the polymerization is carried out in the presence of a catalyst component formed of a compound of a transition metal of the sub-groups IVa, Va and VIa, and a co-catalyst component of at least one organo-metallic compound of a metal from groups II and III of the periodic table, in which the co-catalyst is in the form of a liquid which is separately introduced into the reaction vessel on a carrier formed of an inert porous powder which is impregnated with the co-catalyst.

Abstract: Ziegler-type catalysts of enhanced activity are produced by (1) suspending a finely divided polymeric support such as polyethylene in an alkanol solution of a magnesium compound such as magnesium chloride, (2) vaporizing the alkanol to deposit the magnesium compound on the support, (3) treating the magnesium compound impregnated support with a transition metal halide such as titanium tetrachloride in a hydrocarbon medium, and (4) reacting the product of (3) with an organometallic compound such as triethyl aluminum. The catalysts are particularly useful in polymerizing mono-1 olefins such as ethylene.

Abstract: The method of polymerizing olefins which includes the preparation of a pre-activated compound of a transition metal of IVa, Va and VIa of the periodic table of elements, in which the transition metal is at least partially in a reduced valency state, in which the pre-activation is carried out by contacting the transition metal compound with an organomagnesium compound and then polymerizing the olefins in the presence of the pre-activated transition metal compound and an organo-aluminum compound.

Abstract: A catalyst for the preparation of low-pressure polyethylene comprising the reaction product, at a temperature of from 0.degree. to 100.degree. C, of(A) a reaction product of a dialkyl aluminum hydride with a polysiloxane having a viscosity of from 5 to 100 cSt (25.degree. C) and siloxane units having the formula ##EQU1## in a molar ratio of from 0.8 to 2 mols of said siloxane units per mol of said dialkyl aluminum hydride, withB. a compound of the formulaeTiX.sub.4.sub.-n (OR").sub.n , VX.sub.4.sub.-n (OR").sub.n, and VOX.sub.3.sub.-n (OR").sub.nWhere X is halogen, R" is an aliphatic hydrocarbon, and n is an integer from 0 to 2; as well as a method of producing low-pressure polyethylene utilizing said catalyst.

Abstract: This invention provides a method for the preparation of polyolefins by polymerizing or copolymerizing an olefin or olefins in the presence of a catalyst composed of a titanium compound and/or vanadium compound component supported on a solid carrier and an organometallic compound component, said solid carrier comprising a reaction product obtained by reacting (1) an aluminum compound represented by the general formula Al(OOCR)(OR').sub.2 wherein R and R' being the same or different each represent alkyl, aryl or aralkyl and (2) a magnesium compound represented by the general formula Mg(OR').sub.2 where R" being the same as or different from R and/or R' is alkyl, aryl or aralkyl at a molar ratio of (1):(2) of substantially at least 2:1.