Abstract: A process for the stereoregular polymerization of alpha olefins which comprises polymerizing an alpha olefin having from 2 to 8 carbon atoms in the presence of a catalyst comprising: (a) a solid supported titanium tetrahalide complex, wherein said complex is prepared by contacting a mechanically pulverized solid support with titanium tetrahalide in the absence of mechanical pulverization, and (b) a cocatalyst comprising a mixture of a dialkyl aluminum halide and a dialkyl magnesium or alkyl lithium compound.

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 the preparation of linear low density polyethylene by the copolymerization of ethylene and 1-butene which comprises contacting ethylene with a feedstock comprising 1-butene in the presence of a catalyst comprising:(a) a solid supported titanium tetrahalide complex, wherein said complex is prepared by contacting a mechanically pulverized solid support with titanium tetrahalide in the absence of mechanical pulverization, and(b) a cocatalyst comprising a mixture of dialkyl aluminum halide and a dialkyl magnesium or alkyl lithium compound.

Abstract: A supported solid catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier with a transition metal compound. The carrier utilized in the synthesis must have such an average pore diameter that the resulting catalyst composition has an average pore diameter of at least about 170 Angstroms. The catalyst composition has higher productivity than similar catalyst compositions of lower average pore diameter, and it produces polymers of lower density and higher melt and high load melt indexes than such similar catalyst compositions of lower average pore diameter. Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst of the invention.

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 invention concerns a process for manufacturing low density linear polyethylene by copolymerizing ethylene and 1-butene, comprising the steps of:(a) dimerizing ethylene to 1-butene in the presence of a soluble catalyst comprising: an alkyl titanate, an aluminum compound of formula AlR.sub.3 or AlR.sub.2 H, wherein R is a hydrocarbyl radical, and an ether;(b) contacting at least a portion of the product obtained in step (a) with an inorganic compound, at least partly insoluble;(c) contacting the insoluble mixture obtained in step (b) with an halogenated aluminum compound of formula Al.sub.2 R'.sub.6-n X.sub.n, wherein R' is a hydrocarbyl radical, X a halogen atom, and n a number from 3 to 6, when an halogenated aluminum compound is not already present in said mixture;(d) using the resultant product, containing at least one inorganic carrier, at least one halogenated aluminum compound and at least one titanium compound, as catalyst in the polymerization reactor.

Abstract: The invention relates to a catalyst system comprising (a) a compound of a rare earth element and, as cocatalyst, a second component (b) comprising an organomagnesium compound. In the polymerization of a conjugated diene this catalyst gives a polymer having a very high content of trans 1,4 isomer. A third component (c) which is a Lewis acid alters the reaction to give a polymer having a very high content of cis 1,4 isomer. If desired reaction can be initiated using components (a) and (b) alone and component (c) then added at the desired conversion to produce a block polymer having a block of high trans content followed by a block of high cis content.

Abstract: A catalyst composition for polymerizing alpha-olefins in a gas phase continuous process is prepared by combining a catalyst precursor with a catalyst activator in such proportions that the polymer product comprises about 9.times.10.sup.-7 to about 18.times.10.sup.-7 gram-moles of the activator per gram of the polymer produced. The use of the activator in these proportions lowers the partial pressure of the monomers used in the process without sacrificing quality of the product. The catalyst precursor is prepared by reacting a carrier having OH groups with a stoichiometric excess, with respect to the OH groups, of an organomagnesium composition, and subsequently reacting the product with a transition metal compound.

Abstract: A catalyst composition for use in polymerizing alpha olefins which comprises (a) a solid supported titanium tetrahalide complex, wherein said complex is prepared by contacting a mechanically pulverized solid support with titanium tetrahalide in the absence of mechanical pulverization, and (b) a cocatalyst comprising a mixture of a dialkyl aluminum halide and a dialkyl magnesium compound.

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 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: Alpha-olefin polymerization catalysts are prepared by heating a solid porous carrier having reactive OH groups in the atmosphere of an oxygen-containing gas. The resulting catalysts exhibit higher productivity and produce ethylene polymers or ethylene/C.sub.3 -C.sub.10 copolymers having higher bulk density than similar catalysts prepared with the carriers heated in an atmosphere of nitrogen.

Abstract: Ethylene and alpha-olefins are homopolymerized or copolymerized with another olefin monomer in the presence of a catalyst system comprising an organo metal cocatalyst and titanium-containing catalyst component, said titanium-containing catalyst component being obtained by reacting together a porous particulate material, an organic magnesium compound, optionally an oxygen containing compound, titanium tetrachloride and a Group IIIa metal hydrocarbyl dihalide.

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 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 or organometallic compound selected from an element of Periodic Groups IA, IIA and IIIA.

Abstract: A catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier containing OH groups with an organomagnesium composition and contacting the thus-formed magnesium-containing carrier with a solution of a titanium (IV) alkoxide and a brominating and/or chlorinating agent. The adjustment of the molar ratio of the brominating and/or chlorinating agent to the titanium alkoxide yields catalysts which produce polymers of varying molecular weight distribution, as measured by the melt flow ratio (MFR) values. Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst composition.

Abstract: A process is provided for the polymerization of olefins in the gas phase wherein olefins are contacted with a catalyst system consisting of an active solid hydrocarbon having been prepared by forming a pulverulent composition by mixing a transition metal component, a porous organic or inorganic solid support and an organometallic compound of the organo-Al, organo-Mg or organo-Zn type, and polymerizing a controlled amount of one or more C.sub.2 to C.sub.12 olefins in the gas phase in contact with the pulverulent composition with a specific hourly conversion of the olefins to produce the active solid hydrocarbon.

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 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: Olefins are polymerized in the presence of catalysts prepared from titanium compounds prepared by reacting a titanium compound such as titanium tetraisopropoxide with a compound containing at least one aliphatic hydroxyl group.

Abstract: A catalyst composition for polymerizing alpha-olefins in a gas phase continuous process is prepared by combining a catalyst precursor with a catalyst activator in such proportions that the polymer product comprises about 9.times.10.sup.-7 to about 18.times.10.sup.-7 gram-moles of the activator per gram of the polymer produced. The use of the activator in these proportions lowers the partial pressure of the monomers used in the process without sacrificing quality of the product. The catalyst precursor is prepared by reacting a carrier having OH groups with a stoichiometric excess, with respect to the OH groups, of an organomagnesium composition, and subsequently reacting the product with a transition metal compound.

Abstract: A catalyst composition for use in polymerizing alpha olefins which comprises a solid supported titanium complex and a cocatalyst comprising a mixture of an alkyl aluminum halide and a dialkyl magnesium or alkyl lithium compound.

Abstract: The invention relates to a process for preparing supported catalysts for the copolymerization of ethylene with higher alpha-olefins, characterized in that a compound of a transition metal of Groups IV, V and VI of the Periodic Table of Elements, used at its maximum valency, is precipitated on to a support of magnesium chloride and possibly aluminum chloride by a reduction reaction in two stages, employing reducing agents selected for the first stage from among alkylaluminum dihalides, and for the second stage from among organo-metallic compounds with a higher reducing power than that of the alkylaluminum dihalides.These catalysts are particularly well suited to the copolymerization in the gas phase of ethylene and higher alpha-olefins.

Abstract: Olefins are polymerized in the presence of catalysts prepared from titanium compounds prepared by reacting a titanium compound such as titanium tetraisopropoxide with a compound containing at least one aliphatic hydroxyl group.

Abstract: The viscosity of hydrocarbon solutions of dialkylmagnesium compounds are reduced by using a reducing agent comprising a defined benzene derivative, a substance produced by reacting such a benzene derivative with magnesium or a dialkylmagnesium compound or a mixture of one of the foregoing with an organoaluminum viscosity reducing agent.

Abstract: A process for preparation of a transition metal component of a catalytic system for the polymerization of olefins, wherein an organo-magnesium-aluminum reaction product is formed by bringing into contact, a halogenated, alkylated or alkoxylated magnesium compound with an organo-aluminum compound, then subjecting the reaction product to a chlorination and to a treatment by a compound of a transition metal such as Ti, V, Zr and Cr.As an organo-aluminum compound there is used one or several aluminoxane compounds of the formula ##STR1## wherein R' is an alkyl or from C.sub.1 to C.sub.16, the R"s form together a radical --O-- or designate each a radical R' and n is an integer of from 0 to 20.The transition metal component obtained can be used in combination with a co-catalyst and eventually an electron donor to form a catalytic system apt to polymerize the alpha-olefins.

Abstract: A catalyst system for the polymerization of olefins which comprises;(A) a hydrocarbyloxy group-containing solid catalyst component prepared by (i) reducing a titanium compound represented by the general formula Ti(OR.sup.1).sub.n X.sub.4-n wherein, R.sup.1 represents a hydrocarbon radical of 1-20 carbon atoms, X represents a halogen atom, and n represents a number satisfying 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 represents a hydrocarbon radical of 1-20 carbon atoms, Y represents a halogen atom, and m represents a number satisfying 1.ltoreq.m.ltoreq.3, and (ii) treating the resulting, hydrocarbon solvent-insoluble, hydrocarbyloxy group-containing solid product in a slurry state with an ether compound and titanium tetrachloride at a temperature of 30.degree.-120.degree. C., and(B) an organoaluminum compound.

Abstract: A process for the polymerization of ethylene using as the catalyst a novel solid catalytic complex comprising Mg, Si, and either Ti or V. An organoaluminum co-catalyst is also employed. The novel catalytic complex is prepared by a process which comprises:(a) reacting a silanol having the formula ##STR1## where R, R' and R" can be the same or different and are selected from the group consisting of aliphatic hydrocarbons having from 2 to 12 carbon atoms or phenyl or substituted phenyl where such substituents have from one to three alkyl groups, and alkyl group having from one to four carbon atoms and where R" can additionally be selected from --OH, with a magnesium dialkyl where each alkyl group can have from one to 12 carbon atoms to form a first reaction product;(b) reacting said first reaction product with trichlorosilane to form a second reaction product; and(c) reacting said second reaction product with a metal compound having the formula:MeX.sub.

Abstract: A Ziegler type supported catalytic component for polymerization of an .alpha.-olefin is prepared by allowing an organo-magnesium compound expressed by a generic formula of R'MgX' (wherein R' represents a hydrocarbon group having 1 to 20 carbon atoms and X' either a halogen atom chosen out of chlorine, bromine and iodine or a hydrocarbon group having 1 to 20 carbon atoms) to react with carbon tetrahalide in the presence of an electron donor compound to obtain a solid product through a solid-liquid separation process; by heat treating the separated solid product with a carbon halide; by treating the heat treated solid product with phenols at 90.degree. to 180.degree. C.; and by treating this phenol treated product further with a halogenated titanium compound. Homo- or co-polymerization of an .alpha.-olefin is carried out in the presence of a catalyst composition consisting of the above catalytic component and an organo-aluminum compound. With this catalytic component, stereospecific polymerization of an .alpha.

Abstract: The invention relates to a method of polymerizing one or more conjugated diene monomers to a polymer having an exceptionally high cis content employing a three component catalyst comprising (a) a rare earth compound, (b) an organo magnesium compound and (c) a Lewis acid in which a particular order of component addition is used. Under optimum conditions it is possible to obtain nearly 100% conversion to polymers of 98% or more cis content at very low concentrations of rare earth compound with respect to monomer.

Abstract: A catalyst component for polymerizing ethylene alone or with another alpha-olefin having from 3 to 18 carbon atoms at temperatures greater than about 150.degree. C. which catalyst component is the product obtained by treating at least one dehydrated particulate support material, such as silica, having an average particle size from about 0.05 to about 20 microns, preferably 1.0 to 10.0 microns, with(a) at least one dihydrocarbyl magnesium compound wherein the hydrocarbyl groups can be the same or different, such as butyl ethyl magnesium,(b) a transistion metal compound of Groups IVa, Va, or VIa of the Periodic Table, such as, for example, titanium tetrachloride, and (c) ethyl aluminum dichloride. In a preferred embodiment the particulate support material is treated with a halogenating agent prior to treatment with the transition metal compound.

Abstract: A catalyst system for the polymerization of olefins comprising:(A) a solid catalyst component containing hydrocarbyloxy groups obtained by reacting a titanium compound represented by the general formula Ti(OR.sup.1).sub.n X.sub.3-n (wherein R.sup.1 is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen atom, and n is a number defined by 0<n.ltoreq.3) with an ether compound and titanium tetrachloride in a slurry state in the presence of a magnesium halide, and(B) an organoaluminum compound.

Abstract: A method for polymerization of ethylene and copolymerization of ethylene with other 1-olefins at high temperatures in the presence of a transition metal catalyst and a tetra alkyl-.mu.-oxodialuminum compound.

Abstract: A catalyst comprising the product obtained by bringing into contact (a) a compound of magnesium comprising at least one species selected from the group consisting of magnesium monohalides (MgX), halo-magnesium hydrides (HMgX) and magnesium hydride (MgH.sub.2), X being a halogen and the said species MgX or HMgX being obtained by thermal decomposition of a powdery organo-magnesium halide R.sub.1 MgX wherein R.sub.1 is an organic radical; and (b) at least one halide of a transistion metal selected from the group consisting of titanium and vanadium, the valency of said metal in said halide being lower than or equal to 3, the quantities of (a) and (b) being such that the atomic ratio of magnesium to said transistion metal is between 1 and 25, and a catalyst system including the catalyst that is suitable for use in the polymerization of olefins and particularly ethylene.

Abstract: A catalyst component is a transition metal composition which is obtained by reacting together an inert particulate material, an organic magnesium compound, a halogen-containing compound such as carbon tetrachloride or silicon tetrachloride and a specified transition metal compound. The catalyst component obtained can be used, together with an organic metal compound, to give an olefin polymerization catalyst. The catalyst can be used to effect the polymerization of olefin monomers, for example, the copolymerization of ethylene with an alpha-olefin monomer such as butene-1 in a fluidized bed reactor.

Abstract: The invention is addressed to solid catalysts comprising essentially compounds of magnesium and of transition metals selected from the sub-groups IVa, Va and VIa of the periodic table, applicable to the polymerization of olefins and particularly ethylene, in which the catalyst is obtained by first preparing a solid compound of magnesium, monohalogenated hydrocarbon and halogen and/or organic derivatives of the transition metal in a state of valency of at least 4 and then reacting the solid compound of magnesium and transition metal with an oxidizing compound.

Abstract: This invention discloses a process of preparing a catalyst component for the polymerization of .alpha.-olefins. An organomagnesium compound is deposited on an inert inorganic support, such as silica, and the product obtained is heated at a temperature of 300.degree.-1000.degree. C. in a non-reducing atmosphere. The support is then combined with one or more compounds of titanium and/or vanadium. The process of polymerizing .alpha.-olefins with the catalysts of this invention is also disclosed.

Abstract: Improved process for preparing an ethylene polymer wax which comprises polymerizing ethylene or copolymerizing ethylene with up to 10 mole % of an alpha-olefin having 3 to 20 carbon atoms in the presence of (A) a highly active titanium catalyst component activated by a magnesium compound and (B) an organoaluminum catalyst component composed of (B-1) an organoaluminum compound free from halogen bonded directly to the aluminum atom and (B-2) a halogen compound of an element selected from the group consisting of elements other than titanium of Groups III and IV of the Mendelejeff's periodic table, the atomic ratio of halogen to aluminum in the organoaluminum catalyst component (B) being from about 1:6 to about 9:10, provided that when said halogen compound is a halogen compound of carbon, this atomic ratio is from about 1:6 to about 10:1, and said polymerization or copolymerization being carried out under such conditions that the concentration of ethylene polymer wax in the polymerization or copolymerization sys

Abstract: Olefins are polymerized in the presence of a catalyst prepared by reacting a mixture of a tetrahydrocarbyloxy titanium compound such as tetraisopropyl titanate and a hydrocarbyloxy titanium oxide such as di(isopropoxy) titanium oxide, an organomagnesium component such as a hydrocarbon soluble complex of dialkyl magnesium and an organoaluminum compound such as triethyl aluminum and a halide source such as ethyl aluminum dichloride. The catalysts employed in this process provide higher efficiencies than these catalysts employing either of the titanium compounds alone.

Abstract: According to this invention, there is provided a process for preparing a low-crystalline soft or semi-hard copolymer, characterized in that 90 to 98 mole % of propylene, 0.2 to 9 mole % of ethylene and 0.2 to 9 mole % of a straight-chained (.alpha.-olefin having not less than four carbon atoms are copolymerized using a catalyst, said catalyst comprising (1) a solid substance containing magnesium and titanium, (2) an organometallic compound and (3) an electron donor.

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 polymerization activator for polymerizing ethylene comprising a dialkylaluminum monofluoride mixed with minor amounts of at least one of dialkylaluminum hydride or halide and a trialkylaluminum. The activator preferably corresponds to the general formula (AlR.sub.2 F)(AlR.sub.2 H).sub.b (AlR.sub.3).sub.c or the general formula (AlR.sub.2 F)(AlR.sub.2 X).sub.a wherein R is an alkyl group having 1 to 12 carbon atoms, 0.1.ltoreq.b.ltoreq.0.4, 0.05.ltoreq.c.ltoreq.0.2, X is a halogen other than fluorine, and 0.1.ltoreq.a.ltoreq.0.4. The activator is used in a catalytic system including at least one halide of a transition metal of Group IVB to VIB, the valency of the metal in the halide being not more than 3 and the atomic ratio of aluminum in the activator to transition metal in the catalyst lying between 0.1 and 10. The catalytic system is used in a high pressure and temperature process for polymerizing or copolymerizing ethylene.

Abstract: A new improved catalyst system for alpha-olefin type polymerizations includes a metal alkyl compound selected from the group consisting of R.sub.2 WY or R.sub.3 W and an organomagnesium compound R'MgX in combination with a Group IVB-VIII transition metal compound. The improved catalyst system provides both increased polymerization activity and polymers having a high degree of isotactic stereoregularity.

Abstract: This invention relates to a supported catalyst and to the use of this catalyst in a process for the polymerization of alpha-olefins. The catalyst comprises a transition metal complex supported on an interpolymer comprising an alpha, beta-unsaturated dicarboxylic acid, anhydride or lower alkyl ester thereof, and one or more monomers copolymerizable therewith which has been treated with a Group IIA halide or alkyl halide. Preferred supports comprise maleic anhydride copolymers which have been treated with a magnesium compound.

Abstract: A process for polymerizing olefins employing as a catalyst therefor, the reaction product of (A) the reaction product of (1) the reaction product of (a) an alkyl magnesium compound such as dibutylmagnesium, with (b) an oxygen-containing and/or nitrogen-containing compound such as n-propyl alcohol, or isopropylamine, with (2) a halide source such as titanium tetrachloride or silicon tetrachloride; and (B) a transition metal compound such as titanium tetrachloride and (C) a reducing agent such as triisobutylaluminum. The polymers which are produced in the presence of this catalyst and a cocatalyst such as triethylaluminum have a low catalyst support to transition metal ratio and therefore, the catalyst efficiency based on quantity of polymer per quantity of total catalyst is very high resulting in a polymer having good color and very little, if any, corrosion.

Abstract: A new improved catalyst system for alpha-olefin type polymerizations includes a metal di- or tri-halide compound of Al, Ga, or In and a diorganomagnesium compound in combination with a Group IVB-VIII transition metal compound. The improved catalyst system provides increased polymerization activity and polymers having a high degree of isotactic stereoregularity.

Abstract: An olefin polymerization and copolymerization catalyst active in the presence of an alkyl aluminum cocatalyst is prepared by mixing, in the presence of a solvent, particles of a silica or alumina material having reactive surface groups, and a complex of the general formula (MgR.sub.2).sub.m (AlR'.sub.3).sub.n where R and R' are alkyl groups and m/n is between about 0.5 and 10, inclusive, to form a hydrocarbon insoluble reaction product which is then mixed, in the presence of a solvent, with a titanium, vanadium or zirconium halide, oxyhalide or alkoxyhalide, followed by evaporation of the solvent.

Abstract: A catalyst suitable for polymerizing an .alpha.-olefin, comprising a solid catalyst component [A] and an organometal compound [B], the solid catalyst component [A] being prepared by reacting an organomagnesium compound (1) soluble in a hydrocarbon medium and represented by the general formula,MgR.sub.p.sup.1 R.sub.q.sup.2 X.sub.r.Z.sub.swhereinR.sup.1 is a hydrocarbon group having 2 to 3 carbon atoms;R.sup.2 is a hydrocarbon group having 4 to 20 carbon atoms and the difference in number of carbon atoms between R.sup.1 and R.sup.2 is at least 2;X is an electronegative group having an oxygen atom, a nitrogen atom or a sulfur atom;Z is an organometal compound of aluminum, boron, beryllium, zinc, silicon or lithium;p and q each is a number above 0 to 1;r is a number from 0 to 1;p+q+r=2; ands is a number from 0.02 to 0.09,with a titanium and/or vanadium compound (2) having at least one halogen atom; and a process for polymerizing an .alpha.-olefin employing the same catalyst.

Abstract: In a slurry polymerization for producing an ethylene homopolymer or ethylene-.alpha.-olefin copolymer in multiple stages, in which the gas phase hydrogen concentration in each stage is different, using a catalyst system comprising a transition metal compound component and an organoaluminum compound component, the improvement which comprises conducting the polymerization by the use of a solid catalyst component comprising a titanium compound and/or vanadium compound supported on a specified magnesium compound, as the transition metal compound component, in a molar ratio of gas phase hydrogen to ethylene of 0.5 to 15 in the first stage thereby obtaining 30 to 95% by weight, of the total polymer, and in the second stage in a molar ratio of gas phase hydrogen to ethylene, not exceeding 0.2. By this process, it is possible to produce polyethylene having high melt flow and good homogeneity to give molded articles having fewer fish-eyes and less unevenness.

Abstract: Solid catalyst components produced by reacting an organomagnesium compound with an alkoxy compound of the formula,R.sup.1.sub.a Al(OR.sup.2).sub.b X.sub.cwherein R.sup.1 and R.sup.2 are each a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen atom and a, b and c are numbers satisfying the equations at the same time,0.ltoreq.a<3, 0<b.ltoreq.3, 0.ltoreq.c<3, and a+b+c=3 and/or of the formula,R.sup.3.sub.d P(OR.sup.4).sub.e X.sub.fwherein R.sup.3 and R.sup.4 are each a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen atom, and d, e and f are numbers satisfying the equations at the same time,0.ltoreq.d<3, 0<e.ltoreq.3, 0.ltoreq.f<3, and d+e+f=3to produce a solid product, and allowing the solid product to support a titanium compound and/or a vanadium compound, and a method for producing polyolefins which comprises polymerizing olefin in the presence of a catalyst system comprising said solid catalyst component and an organoaluminum compound.