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 solid catalyst component for alkene polymerization comprising a magnesium halide, an electron donor and a phenoxy-titanium halide, the latter being a dihalophenoxy-titanium halide or a dialkoxyphenoxy-titanium halide in which the alkoxy groups each have from 1 to 8 carbon atoms.

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

Abstract: Olefins of the formulaR.sup.11 --CH.dbd.CH--R.sup.12(R.sup.11 and R.sup.12 =H or C.sub.1 -C.sub.14 -alkyl) are polymerized in the presence of a catalyst comprising at least one metallocene of the formula I ##STR1## (M=zirconium or hafnium) and an aluminoxane, giving polymers of high molecular weight in high yield.

Abstract: A vanadium dichloride-ether complex is carried on a porous support. This complex can be produced by either forming VCl.sub.2 and thereafter complexing the material with an ether or forming an ether complex with VCl.sub.4 or VCl.sub.3 and thereafter reducing the vanadium compound to VCl.sub.2. It is also possible to carry out the complexing reaction and the reduction essentially simultaneously. The resulting catalyst in combination with a cocatalyst is capable of giving high activity in olefin polymerization and demonstrates good sensitivity to molecular weight control agents, thus allowing the production of a broad spectrum of polymers so far as molecular weight is concerned.

Abstract: Homopolymerization and copolymerization of ethene is carried out using a Ziegler catalyst system consisting of (1) a transition metal catalyst component, (2) an organoaluminum catalyst component and (3) an organohalogen catalyst component. The component (1) used is the solid-phase product (VI) which has been obtained by a method in which (1.1) first (1.1.1) an inorganic oxidic substance (I) as a carrier and (1.1.2) a solution (II) of (IIa) a certain oxahydrocarbon and (IIb) a mixture of (IIb1) a vanadium trichloride/alcohol complex and (IIb2) a titanium trihalide or titanium trihalide/alcohol complex and (IIc) a silicon or boron compound are combined with formation of a suspension (III) and the latter is evaporated to form a solid-phase intermediate (IV) and (1.2) then (1.2.1) the intermediate (IV) obtained in (1.1) and (1.2.

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: Disclosed is a catalyst composition for use in the polymerization of olefins, which is comprised of (a) a catalyst component containing magnesium, titanium, a halogen, and an ingredient derived from a keto-ester compound, and (b) an organic aluminum compound. The catalyst activity and capability of providing a highly stereoregular polymer are enhanced by preparing the catalyst component (a) by a process wherein, during or after the formation of a solid catalyst component containing magnesium, titanium, and a halogen, the solid catalyst component is treated with a keto-ester of the formula: ##STR1## wherein R.sup.1, R.sup.2 and Z represent a hydrocarbon group.

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

Abstract: Crystalline, isotactic homopolymers of cycloolefins or elastic copolymers made from cycloolefins and linear olefins are obtained, without ring opening of the cycloolefins, at industrially favorable polymerization temperatures by means of a catalyst which comprises a stereorigid, chiral metallocene compound of groups IVb to VIb of the Periodic Table of the Elements and an aluminoxane.

Abstract: The present invention relates to a process for polymerizing olefins.In the process of the present invention, olefins are polymerized using a catalyst composed of a compound of a transition metal (e.g. zirconium) of Group IVB of the periodic table, an aluminoxane produced from trimethylaluminum, and an aluminoxane wherein at least one hydrocarbon group other than n-alkyl groups is bonded to an aluminum atom. The present process can polymerize olefins with excellent polymerization activity and can produce an olefin polymer having a relatively large molecular weight even when the use amount of the aluminoxane produced from trimethylaluminum (which is expensive) is small.

Abstract: If the transition metal component used in an olefin polymerization catalyst is the product of the reaction between a siloxane-substituted metallocene of titanium, zirconium or hafnium and a hydroxyl group-containing support material, for example silicon dioxide, these metallocene catalysts can be employed in existing polymerization plants which are designed for the suspension process.

Abstract: A method for activating supported chromium oxide catalysts in which a chromium-containing catalyst on a silica-containing base is first heated in an oxidizing atmosphere at temperatures up to about 850.degree. C. and then cooled down. During the cooling step of the catalyst, the oxidizing atmosphere is replaced by a non oxidizing one, leading to an activated catalyst.A process for the polymerization of alpha-olefins, especially ethylene, in which at least one alpha-olefin is contacted, under polymerization conditions, with the catalyst activated by the method described above.

Abstract: Ethylene 1,3 Butadiene copolymers having in their structure cyclopentane rings connected in a trans 1,2 position. The ethylene copolymers of the invention may be formed from polymerization of ethylene and 1,3 butadiene and preferably have a predominance of the copolymer units formed as trans 1,2-cyclopentane, the remainder of the 1,3 butadiene comonomer being incorporated as the noncyclic.

Abstract: An inert hydrocarbon solvent-soluble catalyst for polymerization of olefinic hydrocarbons and a process for producing an olefinic polymer using the same are disclosed, the catalyst being composed of (A) a reaction product obtained by reacting (a) at least one vanadium compound represented by formula:VO(OR).sub.m X.sub.3-mwherein R represents a hydrocarbon group; X represents a halogen atom; and m represents a real number of from 0 to 3, and (b) a dihydroxy hydrocarbon compound constituted of a straight chain hydrocarbon skeleton containing from 2 to 12 carbon atoms and having a hydroxyl group at each of both terminals thereof and at least one hydrocarbon branch bonded to said hydrocarbon skeleton in an inert hydrocarbon solvent at an (a) to (b) molar ratio of from 1:0.5 to 1:1.4 and (B) at least one organoaluminum compound represented by formula:R'.sub.n AlX'.sub.3-nwherein R' represents a hydrocarbon group; X' represents a halogen atom; and n represents a real number more than 0 and less than 3.

Abstract: A process for producing an .alpha.-olefin polymer which comprises homopolymerizing or copolymerizing an .alpha.-olefin by the use of a catalyst system comprising:(A) a solid catalyst component (A) containing at least magnesium, titanium, halogen and ester compound as indispensable components, and(B) a catalyst component (B) produced by reacting an organoaluminum compound represented by general formula R.sup.1.sub.m AlY.sub.3-m (R.sup.1 represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms, Y represents halogen, hydrogen or alkoxy group having 1 to 20 carbon atoms, and m represents a number satisfying 2.ltoreq.m.ltoreq.3) with an organic silicon compound represented by general formula R.sup.2.sub.n Si(OR.sup.3).sub.4-n (R.sup.2 represents alicyclic hydrocarbon group or aromatic hydrocarbon group having 5 to 20 carbon atoms, R.sup.3 represents a hydrocarbon group having 1 to 20 carbon atoms, and n represents a number satisfying 0.ltoreq.n.ltoreq.

Abstract: An olefin polymerization supported catalyst comprising the supported reaction product of at least one metallocene of a metal of Group IVB, VB, and VIB of the Periodic Table, a non-metallocene transition metal containing compound of a Group IVB, VB, or VIB metal and an alumoxane, said reaction product formed in the presence of the support. The supported product is highly useful for the polymerization of olefins especially ethylene and especially for the copolymerization of ethylene and other mono and diolefins.

Abstract: Herein is disclosed a vulcanizable rubber composition comprising a copolymer rubber constituted of ethylene, propylene and nonconjugated polyene, wherein ethylene/propylene molar ratio is 78/22 to 97/3 and the total content of propylene and nonconjugated polyene is 6 to 30% by mole in said copolymer rubber. By the use of the rubber composition of the present invention, a vulcanized product excellent in tensile strength, heat resistance, oil resistance, compression set resistance and flex behavior can be obtained. The vulcanized product can be used as automobile parts and other innumerable articles such as socket cover, heat resistant hose, electric wire, condenser cap, heat resistant belt, vibration-proof rubber, hoses, weather strip, seal sponge, black side wall of tire, etc.

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.