Abstract: A solid titanium catalyst component ?Ia! containing magnesium, halogen, titanium and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a catalyst and a prepolymerized olefin-containing catalyst prepared by using the solid titanium catalyst component ?Ia!; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used. A catalyst and a prepolymerized olefin containing catalyst prepared by using a solid titanium catalyst component ?Ib! containing magnesium, halogen, titanium and a specific electron donor (al), and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used.

Abstract: Disclosed is a process for preparing an ethylene-.alpha.-olefin-nonconjugated polyene random copolymer comprising random copolymerizing (a) ethylene, (b) an .alpha.-olefin of 3 or more carbon atoms and (c) a nonconjugated polyene in the presence of a metallocene catalyst containing a specific metallocene compound. The ethylene-.alpha.-olefin-nonconjugated polyene random copolymer prepared by the process has such properties that (i) the copolymer contains units derived from ethylene (a) and units derived from the .alpha.-olefin of 3 or more carbon atoms (b) in a molar ratio of 40/60 to 95/5 ?(a)/(b)!, (ii) the iodine value is 1 to 50, (iii) the intrinsic viscosity (.eta.) is more than 0.1 dl/g and less than 8.0 10 dl/g, (iv) the intensity ratio D of T.alpha..beta. to T.alpha..alpha. in the .sup.13 C-NMR spectrum, T.alpha..beta./T.alpha..alpha., is not more than 0.5, (v) the B value is 1.00 to 1.50, (vi) the glass transition temperature Tg is not higher than -50.degree. C., and (vii) the ratio g.eta.

Abstract: Process for the in situ polymerization of ethylene with C.sub.3 -C.sub.10 alpha-olefins in suspension of liquid monomer in the presence of a catalyst containing Vanadium obtained by the precipitation, in an atmosphere of ethylene or alpha-olefins, of:a) a compound of Vanadium in the oxidation state of 3 to 5, withb) a basically hydrocarbon solution of a compound selected from those having general formula R.sub.n AlX.sub.m wherein R is a C.sub.1 -C.sub.20 alkyl radical, X is a halogen, m+n=3, n is an integer from 0 to 2.

Abstract: A process for the production of polyolefins is provided which comprises polymerizing or copolymerizing olefins in the presence of a catalyst composition which includes a catalyst component (I) resulting from mutual contact of sub-components (A) and (B), and a catalyst component (II). Sub-component (A) is of the formulaR.sup.1.sub.p Me.sup.1 X.sup.1.sub.4-p and/or R.sup.1.sub.2 Me.sup.1 X.sup.1'and sub-component (B) is a modified organoaluminum compound having Al--O--Al bonds. Catalyst component (II) is an admixture of sub-component (C), which is a transition metal elemental compound of Groups VII-VIII, and one or more of triethylaluminum, triisobutylaluminum, diethyl zinc, n-butyllithium, and butylmagnesiumchloride. The catalyst components (I) and/or (II) are contacted with a carrier during or after the preparation of the components (I) and/or (II).

Abstract: Diene rubbers are produced in the gas phase by first polymerizing the dienes or diene mixtures in the presence of a catalyst system, which is based on rare earth compounds, at temperatures of from 0 to 150.degree. C. and at pressures of from 1 mbar to 50 bar, so that a pourable diene rubber having a Mooney viscosity ML (1+4', 100.degree. C.) of 70 to 180 Mooney units is obtained, and subsequently subjecting the pourable diene rubber obtained to a chemical or thermal decomposition reaction until a Mooney viscosity of 10 to 70 Mooney units is obtained.

Abstract: Catalyst systems which are suitable for polymerizing olefinically unsaturated compounds comprise as active constituentsA) a metallocene complex of the metals of the fourth, fifth or sixth transition group of the Periodic Table of the Elements,B) a compound forming metallocenium ions andC) a sterically hindered, organic Lewis base.

Abstract: Catalysts consisting ofA) an alcoholate of the rare earths, a carboxylate of the rare earths, a complex compound of the rare earths with diketones and/or an addition compound of the halides of the rare earths with an oxygen or nitrogen donor compound,B) an aluminium trialkyl, a dialkyl aluminium hydride and/or an alumoxane,C) another Lewis acid andD) an inert, particulate inorganic solid with a specific surface of greater than 10 m.sup.2 /g (BET) and a pore volume of 0.3 to 15 ml/gare eminently suitable for the polymerization of conjugated dienes, more particularly butadiene, in the gas phase.

Abstract: A high cis-1,4-polybutadiene is produced, with reduced gel formation, by preparing a catalyst from (A) a cobalt compound, (B) a trialkyl (C.sub.1-10) aluminum compound, (C) a halide compound selected from those of formulae (1) and (2): (1) AlR.sup.2.sub.m X.sub.3-m, and (2) R.sup.3 --X, wherein R.sup.2 =C.sub.1-10 hydrocarbon, X=halogen, m=0 to 2, R.sup.3 =C.sub.1-40 hydrocarbon, and (D) water in an amount of 0.77 to 1.45 moles per mole of total Al in components (B) and (C); and polymerizing 1,3-butadiene in the presence of the resultant catalyst in a polymerization medium including an alkane, cycloalkane and/or olefin hydrocarbon.

Abstract: There is disclosed a process for producing a styrenic polymer which comprises polymerizing at least one styrenic monomer by the use of a polymerization catalyst comprising in combination (A) at least one transition metal compounds, (B) an aluminoxane, (C) a coordination complex compound comprising a cation and an anion in which a plurality of radicals are bonded to a metal and (D) an organoaluminum compound. The above process is capable of producing a styrenic polymer which has high degree of syndiotactic configuration and a wide range of molecular weight distribution and is minimized in residual metallic components at a low production cast with a high efficiency.

Abstract: Catalyst systems comprising, on the one hand, a catalytic solid based on complexed titanium trichloride and, on the other hand, a nonhalogenated organolauminium activator.When employed in gas phase olefin polymerization processes, these catalyst systems make it possible to manufacture a wide range of homopolymers and copolymers (random and block) with an isotacticity index which can be adjusted to very low values and with excellent pourability, even in the case of copolymers of high comonomer content.In the absence of transfer agents they also make it possible to synthesise polymers of very high molecular masses, with an increased activity.These polymerization processes yield particularly advantageous results in the case of propylene.

Abstract: Catalyst systems comprising, on the one hand, a catalytic solid based on complexed titanium trichloride and, on the other hand, a nonhalogenated organoaluminium activator. When employed in gas phase olefin polymerization processes, these catalyst systems make it possible to manufacture a wide range of homopolymers and copolymers (random and block) with an isotacticity index which can be adjusted to very low values and with excellent pourability, even in the case of copolymers of high comonomer content. In the absence of transfer agents they also make it possible to synthesize polymers of very high molecular masses, with an increased activity. These polymerization processes yield particularly advantageous results in the case of propylene.

Abstract: The present invention provides an ethylene copolymer comprising constituent units (a) derived from ethylene and constituent units (b) derived from an .alpha.-olefin having 3 to 20 carbon atoms, the ethylene copolymer being characterized in that(A) the ethylene copolymer has a density (d) of 0.86 to 0.95 g/cm.sup.3 ;(B) the ethylene copolymer has a MFR of 0.001 to 50 g/10 min as measured at a temperature of 190.degree. C. and a load of 2.16 kg;(C) the melt tension (MT) and MFR of the ethylene copolymer satisfy the relationlog MT>-0.66 log MFR+0.6; and(D) the temperature (T) at which the exothermic curve of the ethylene copolymer measured by a differential scanning calorimeter (DSC) shows the highest peak and the density (d) satisfy the relationT<400 d-250.

Abstract: An ethylene-.alpha.-olefin copolymer having: (A) a density d of 0.86 to 0.96 g/cm.sup.3 ; (B) a melt flow rate MFR of 0.01 to 200 g/10 min; (C) a molecular weight distribution Mw/Mn of 1.5 to 4.5; (D) a composition distribution parameter Cb of 1.08 to 2.00; and (E) an orthodichlorobenzene-soluble content X (wt %), at 25.degree. C. a density of d (g/cm.sup.3) and a melt flow rate MFR (g/10 min) satisfying that: (i) when the density (d) and the melt flow rate MFR satisfy relationship (I):d-0.008.times.logMFR.gtoreq.0.93 (I)the orthodichlorobenzene-soluble content X satisfies relationship (II):X<2.0 (II)(ii) when the density d and the melt flow rate MFR satisfy relationship (III):d-0.008.times.logMFR<0.93 (III)the orthodichlorobenzene-soluble content X satisfies relationship (IV):X<9.8.times.10.sup.3 .times.(0.9300-d+0.008.times.logMFR).sup.2 +2.

Abstract: The present invention provides a catalyst and a process for increased catalyst activity and polymer yield. The catalyst system used in the process includes at least two supported metallocene catalyst precursor in combination with an oxyorganoaluminum. The process can be applied to the polymerization of olefins, preferably olefin of three carbon atoms and higher, particularly propylene. The catalyst activity and polymer yield for a dual supported metallocene catalyst are increased over that for a single supported metallocene catalyst. The polymer produced by this dual supported metallocene system has a relatively broad molecular weight distribution.

Abstract: The present invention provides an ethylene copolymer comprising constituent units (a) derived from ethylene and constituent units (b) derived from an .alpha.-olefin having 3 to 20 carbon atoms, the ethylene copolymer being characterized in that(A) the ethylene copolymer has a density (d) of 0.86 to 0.95 g/cm.sup.3 ;(B) the ethylene copolymer has a MFR of 0.001 to 50 g/10 min as measured at a temperature of 190.degree. C. and a load of 2.16 kg;(C) the melt tension (MT) and MFR of the ethylene copolymer satisfy the relationlog MT>-0.66log MFR+0.6; and(D) the temperature (T) at which the exothermic curve of the ethylene copolymer measured by a differential scanning calorimeter (DSC) shows the highest peak and the density (d) satisfy the relationT<400d-250.

Abstract: In accordance with the present invention, there are provided an olefin polymerization catalyst comprising an organoaluminum oxy-compound (A), a transition metal compound (B) and a hydrogenated organoaluminum compound (C); a solid olefin polymerization catalyst comprising the above-mentioned components (A), (B), (C) and a carrier (D); a prepolymerized catalyst formed by prepolymerization of olefin on a catalyst component comprising the above-mentioned components (A), (B), (C) and (D); an olefin polymerization catalyst comprising the above-mentioned solid olefin polymerization catalyst or the above-mentioned prepolymerized catalyst and an organoaluminum compound; and a method for the polymerization of olefin which comprises polymerizing olefin in the presence of the above-mentioned catalysts.

Abstract: Rubbery, amorphous cyclic olefin/.alpha.-olefin copolymers in a molar ratio from 5/95 to 30/70. The copolymers are rubbery and have the general properties of thermoplastic elastomers, e.g. good elastic recovery, toughness, and high elasticity, and have a relatively low glass transition temperature (Tg) to avoid brittleness and hardness under normal use temperature. The copolymers also have a high molecular weight, a narrow molecular weight distribution and a uniform, random comonomer distribution to impart a rubbery loss modulus plateau over the temperature range from Tg to above 100.degree. C., and are optionally lightly crosslinked or plasticized to further extend their useful temperature range.

Abstract: Process for the preparation of crystalline vinylaromatic polymers with a high degree of syndiotacticity which comprises polymerizing vinylaromatic monomers in the presence of a catalytic system essentially consisting of:a) a complex of titanium selected from those having the general formula:(CpR.sub.1 R.sub.2 R.sub.3 R.sub.4 R.sub.5)TiX.sub.3 (I)wherein the groups R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 represent a hydrogen atom or C.sub.1 -C.sub.10 alkyl groups;X represents a hydrogen atom, a halogen such as chlorine, a C.sub.1 -C.sub.10 alkyl or oxyalkyl radical or a C.sub.6 -C.sub.12 oxyaryl radical;b) an alkylaluminoxane; andc) an organic derivative of tin;characterized in that the alkylaluminoxane is methylaluminoxane (MAO) treated at 20.degree.-80.degree. C. under vacuum for 1-100 hours and the organic derivative of tin is tin tetraphenyl.

Abstract: Cocatalytic composition resulting from bringing an organoaluminium halide (A) into contact with an electron-donating organic compound (ED) selected from esters, amides and ketones, the organoaluminium halide (A) possessing an atomic ratio halogen (X)/aluminium (Al) of greater than 1 and less than 1.3, the halide (A) and the compound (ED) being employed in a mole ratio halide (A)/compound (ED) of greater than 20. Catalytic systems which are usable for the polymerization of alpha-olefins, comprising such a cocatalytic composition and a solid based on titanium trichloride complexed with an electron-donating compound.

Abstract: A process for producing a styrenic polymer having the syndiotactic configuration which process comprises a plurality of polymerization stages, at least one polymerization stage selected as desired from the plurality of polymerization stages being a polymerization stage in which hydrogen is introduced; in accordance with the present invention, efficient control of molecular weight and molecular weight distribution is enabled. By increasing activity of the polymerization catalyst, the amount of the catalyst and the amount of residual metals can be decreased, and the cost of production can be decreased.

Abstract: (Co)polymerisation process according to which a mixture of a halogenated neutral metallocene as defined above and of an organoaluminium compound is prepared, the olefin is brought into contact with this mixture and an ionising agent is added thereto.

Abstract: Metallocene catalysts and their preparation and use in the polymerization of olefins. Specifically, the catalysts and processes relate to polymerization of olefins in which an aluminum ionizing agent containing a triphenylcarbenium ion is utilized in preparing the catalyst. The preparation of an olefin polymerization catalyst comprising a metallocene-type catalyst and triphenylcarbenium tetrakis(pentafluorophenyl)aluminate is disclosed.

Abstract: The present invention provides a catalyst for polymerization comprising (A) a transition metal compound containing at least one linkage represented by the general formula (I):M.sup.1 --Z--C (I)wherein M.sup.1 represents a metal element of Groups 3 to 6 or the lanthanide series, and Z represents an element of Group 15, in one molecule, (B) (a) a compound which can form an ionic complex by the reaction with the transition metal compound or (b) a specific oxygen-containing compound, and (C) a metal compound containing alkyl group which is optionally used; and a process for producing a styrenic polymer, particularly a styrenic polymer having a highly syndiotactic configuration, comprising using this catalyst for polymerization.

Abstract: In a gas phase olefin polymerization, an olefin is continuously fed to a fluid bed reactor in which a metallocene catalyst is present. At least one compound selected from water, alcohols and ketones is added in a specified amount simultaneously with the feeding of the olefin. Thus, an olefin polymer having a satisfactory drop second count index as defined by the below indicated formula is produced: ##EQU1## wherein t.sub.0 and t respectively represent a flow time measured in the flow test according to ASTM D-1775 of the olefin polymer obtained when none of the water, alcohols and ketones is incorporated in the reactor, and when at least one compound of water, alcohols and ketones is incorporated in the reactor. The flowability of the polymer formed in the reactor is excellent, so that blocking, bridging and the like do not occur during the gas phase polymerization. Thus, it is feasible to stably produce a (co)polymer having excellent particle properties in high yield for a prolonged period of time.

Abstract: Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component being prepared by the reaction of the following components ?I! and ?II!:?I! a reaction product obtained by reacting the following components (1), (2) and (3) with one another:(1) a silicon oxide and/or an aluminum oxide;(2) a reaction product obtained by the reaction of a magnesium halide and compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.z, X is a halogen atom, and R is a hydrocarbon radical having 1 to 20 carbon atoms; and(3) a titanium compound represented by the general formula Ti(OR).sub.n X.sub.4-n wherein R is a hydrocarbon radical having 1 to 20 carbon atoms, X is a halogen atom, and n is 0.ltoreq.n.ltoreq.

Abstract: A process for the polymerization of olefinic hydrocarbons is carried out in the presence of a catalyst comprising a catalyst component derived from reacting a compound of the formula Me.sup.1 R.sup.1.sub.n X.sup.1.sub.4-n, a compound of the formula Me.sup.2 R.sup.2.sub.m X.sup.2.sub.z-m, an organocyclic compound having two or more conjugated double bonds and a carrier of inorganic or polymeric material, and a modified organoaluminum compound having Al--O--Al bonds, the resulting polyolefins having a relatively wide molecular weight distribution, a relatively narrow composition distribution and increased bulk density.

Abstract: The present invention provides a process for control of desired properties in the polymer product. The catalyst system used in the process includes a supported metallocene catalyst precursor in combination with an oxyorganoaluminum. The process can be applied to the co-polymerization of propylene and ethylene. The randomness of the ethylene incorporation of the co-polymer product is increased as the amount of ethylene in the feed is increased. The amount of ethylene in the feed is up to 6 wt. % with a resulting amount of ethylene incorporated into the copolymer product up to 4 mole %.

Abstract: There is disclosed a process for producing a styrenic polymer which comprises polymerizing at least one styrenic monomer by the use of a polymerization catalyst comprising in combination (A) at least one transition metal compounds, (B) an aluminoxane, (C) a coordination complex compound comprising a cation and an anion in which a plurality of radicals are bonded to a metal and (D) an organoaluminum compound. The above process is capable of producing a styrenic polymer which has high degree of syndiotactic configuration and a wide range of molecular weight distribution and is minimized in residual metallic components at a low production cast with a high efficiency.

Abstract: A catalyst component for producing polyolefin, a catalyst for producing polyolefin using the catalyst component, and a process for producing polyolefin in the presence of the catalyst. The catalyst component comprises a metallocene compound represented by formula (1): ##STR1## All the symbols in formula (1) are defined in the description.

Abstract: Substantially random ethylene copolymers containing at least 3.0 mole percent of geminally disubstituted olefin monomers are described. The geminally disubstituted olefin monomers can be represented by the generic formula R.sub.1 =R.sub.2 (R.sub.3)(R.sub.4), where R.sub.1 is CH.sub.2, R.sub.2 is C, and R.sub.3 and R.sub.4 are, independently, essentially linear hydrocarbyl groups having from 1 to 30 carbon atoms, or more, and containing one carbon atom bound directly to R.sub.2. The copolymers can be prepared by coordination polymerization by means of contacting at least one geminally disubstituted olefin monomer and ethylene, optionally with one or more other coordination polymerizable monomers, with a catalyst system comprising a monocyclopentadienyl, heteroatom-containing Group 4 transition metal catalyst component.

Abstract: Metallocene catalysts and their preparation and use in the polymerization of olefins. Specifically, the catalysts and processes relate to polymerization of olefins in which an aluminum ionizing agent containing a triphenylcarbenium ion is utilized in preparing the catalyst. The preparation of an olefin polymerization catalyst comprising a metallocene-type catalyst and triphenylcarbenium tetrakis(pentafluorophenyl)aluminate is disclosed.

Abstract: An olefin homogeneous polymerization catalyst demonstrating increased activity is formed from a cyclopentadienyl metallocene component, a salt of a compatible cation and a non-coordinating anion, and a C.sub.3 -C.sub.6 trialkylaluminum, preferably triisobutylaluminum. A homogeneous polymerization process comprises controlling polymerization activity with such catalyst by controlling the aluminum/metal (Al/M) molar ratio to a minimal level within the effective range of Al/M ratios.

Abstract: A catalyst composition comprising A) an aluminoxane-impregnated support prepared by contacting an aluminoxane with an inert carrier material and heating to a temperature of at least about 80.degree. C.; B) a metallocene of the formula:(L).sub.y (L')MY.sub.(x-y-1)wherein M is a metal from groups IIIB to VIII of the Periodic Table; each L and L' is independently a cycloalkadienyl group bonded to M; each Y is independently hydrogen, an aryl, alkyl, alkenyl, alkylaryl, or arylalkyl radical having 1-20 carbon atoms, a hydrocarboxy radical having from 1-20 carbon atoms, a halogen, RCO.sub.2 --, or R.sub.2 N--, wherein R is a hydrocarbyl group containing 1 to about 20 carbon atoms; n and m are each 0, 1, 2, 3, or 4; y is 0, 1, or 2; x is 1, 2, 3, or 4; and x-y.gtoreq.1; C) a bulky aluminum alkyl of the formula:AlR.sup.1.sub.x R.sup.2.sub.(3-x)wherein R.sup.1 is a hydrocarbyl group having 1 to 12 carbon atoms; x is an integer from 0 to 2; R.sup.2 is a hydrocarbyl group of the formula --(CH.sub.2).sub.y -- R.sup.

Abstract: Homopolymers of ethylene or copolymers of ethylene with other olefins or mixtures thereof are prepared by suspension polymerization in the presence of catalyst systems by a process in which the catalyst systems used are those which contain, as active components,A) a finely divided carrier treated with trialkylaluminum,B) a metallocene complex,C) an open-chain or cyclic alumoxane compound andD) an alkali metal alkyl or alkaline earth metal alkyl or a mixture thereof.

Abstract: There is disclosed a process for producing a styrenic polymer, especially, syndiotactic polystyrene, which comprises polymerizing a styrenic monomer by the use of (a) a transition metal compound, (b) a coordination complex compound comprising an anion in which a plurality of radicals are bonded to a metal and a cation or methylaluminoxane, (c) an alkylating agent (alkyl group-containing aluminum, magnesium or zinc compound) and (d) a reaction product between a straight-chain alkylaluminum having at least two carbon atoms and water (alkylaluminoxane). The above process is capable of simplifying the production process and producing high-performance styrenic polymer having a high degree of syndiotactic configuration in high catalytic activity without deteriorating the catalyst activity, increasing the amounts of residual metals in the objective polymer or leaving the decomposition products of the alkylaluminum therein, thereby curtailing the production cost of the objective polymer.

Abstract: A novel titanium (III)-based .beta.-diketonate-coordinated compound is disclosed for catalyzing the polymerization reaction of syndiotactic polystyrenes. The titanium (III)-based compound is represented by the following formula 1: ##STR1## wherein X is a C.sub.1 .about.C.sub.12 alkoxy or amine group, or a halogen atom; R is a C.sub.1 .about.C.sub.12 alkyl, aryl, or alkylsilane group. Preferably, X is N(SiMe.sub.3).sub.2 -- or OMe--, and R is phenyl, methyl, or t-butyl. The titanium (III)-based compounds are prepared by reacting titanium trichloride with diketone and tetrahydrofuran to form an intermediate product, then reacting the intermediate product Ti(AcAc)Cl.sub.2 (THF).sub.2 with either aminosilane or alcohol.

Abstract: Catalyst support containing an .alpha.-olefin polymer which is in the form of particles of mean size from 5 to 350 .mu.m in which the pore volume generated by the pores of radius from 1,000 to 75,000 .ANG. is at least 0.2 cm.sup.3 /g.Catalyst usable for the polymerization of .alpha.-olefins, including a compound containing at least one transition metal belonging to groups IIIb, IVb, IVb and VIb of the Periodic Table, bound in or on this support.

Abstract: A process of polymerizing ethylene with a catalyst using a single metallocene catalyst comprising a bridged metallocene compound having two cyclopentadienyl rings, one substituted with a bulky group in a distal position and one substituted such that a fused ring, substituted or unsubstituted, is formed, which produces a copolymer of ethylene. The metallocene catalyst promotes simultaneous oligomerization of a fraction of ethylene to form a comonomer in situ and copolymerization of the remaining ethylene and the comonomer to form a copolymer.

Abstract: A novel class of olefin polymerization catalyst system based on specific organo-transition metal compounds and which are effective for controlling in particular the width and mode of the molecular weight distribution of the resulting polyolefins, and processes of olefin polymerization using the novel catalyst systems are disclosed.

Abstract: A catalyst active in the (co)polymerization of .alpha.-olefins is obtained by putting the following components in contact with each other:(i) a "bridged" bis-metallocene derivative of a metal M selected from titanium, zirconium or hafnium, wherein the divalent "bridge" has a rigid structure linked to two .eta..sup.5 -cyclopentadienyl ring with two methylene groups having a distance from each other of less than 3.5 .ANG.;(ii) a co-catalyst consisting of an organic derivative of a metal M' selected from boron, aluminium, gallium and tin.Such a catalyst allows high polymerization rates to be reached and is particularly suitable for high temperature polymerization process and co-polymerization of ethylene with other .alpha.-olefins.

Abstract: A process for the preparation of a polyolefin wax by polymerization or copolymerization of olefins or diolefins in suspension and in the presence of a catalyst. The process utilizes a metallocene and a cocatalyst, wherein the metallocene is a compound of the formula I ##STR1## in which M.sup.1 is a metal of group IVb, Vb or VIb of the Periodic Table of Elements, R.sup.1 and R.sup.2 are identical or different and are a hydrogen atom, a C.sub.1 -C.sub.10 -alkyl group, a C.sub.1 -C.sub.10 -alkoxy group, a C.sub.6 -C.sub.10 -aryl group, a C.sub.6 -C.sub.10 -aryloxy group, a C.sub.2 -C.sub.10 -alkenyl group, a C.sub.7 -C.sub.40 -arylalkyl group, a C.sub.7 -C.sub.40 -alkylaryl group, a C.sub.8 -C.sub.40 -arylalkenyl group or a halogen atom and R.sup.3 and R.sup.4 are identical or different and are a mononuclear or polynuclear hydrocarbon radical which may form a sandwich structure with the central atom M.sup.

Abstract: A catalyst comprises a composition resulting from mutual contact of the following Components (A), (B), (C) and (D):said Component (A) being a reaction product resulting from mutual contact of components (a), (b) and (c);said component (a) being represented by the formulaMe.sup.1 R.sup.1.sub.p (OR.sup.2).sub.q X.sup.1.sub.4-p-q Iwherein R.sup.1 and R.sup.2 each are a C.sub.1 -C.sub.24 hydrocarbon moieties, X.sup.1 is a hydrogen atom or a halogen atom, Me.sup.1 is titanium, zirconium or hafnium, p and q are 0.ltoreq.p.ltoreq.4, 0.ltoreq.q.ltoreq.4 and 0.ltoreq.p+q.ltoreq.4,said component (b) being represented by the formulaMe.sup.2 R.sup.3.sub.m(OR.sup.4).sub.n X.sup.2.sub.z-m-n IIwherein R.sup.3 and R.sup.4 each are a C.sub.1 -C.sub.24 hydrocarbon moieties, X.sup.2 is a hydrogen atom or a halogen atom, Me.sup.2 is an element of Groups I to III in the Periodic Table, z is a valence of Me.sup.2, and m and n are 0.ltoreq.m.ltoreq.z, 0.ltoreq.n.ltoreq.z and 0<m+n.ltoreq.

Abstract: Fractionable, reactor blend polypropylenes, directly obtainable from the polymerization reaction of propylene, having:(a) content of isotactic pentads (mmmm) comprised between 25 and 85%;(b) ratio M.sub.w,/M.sub.n <5;containing from 10 to 70% by weight of a fraction soluble in boiling diethyl ether, said fraction having a content of isotactic pentads (mmmm) comprised between 5 and 25%, and from 30 to 90% by weight of a boiling n-heptane-insoluble fraction, soluble in xylene at 135.degree. C., said fraction having a content of isotactic pentads (mmmm) comprised between 50 and 99%, are disclosed. These polymers are suitable as thermoplastic-elastomeric materials. A process for the preparation of these polymers and a process for the preparation of 2-aryl-substituted indenyl metallocene ligands is also disclosed.

Abstract: The present invention relates to a process for controlling molecular weight of a styrenic polymer by adding an organometallic compound such as triethylaluminum when a crystalline styrenic polymer having a highly syndiotactic configuration is produced by using a catalyst for producing a styrenic polymer having the syndiotactic configuration. A styrenic polymer having a highly syndiotactic configuration can efficiently be obtained by homopolymerizing or copolymerizing a styrenic compound in accordance with the process of the present invention. Therefore, the process of the present invention is expected to be advantageously used for producing the styrenic polymer.

Abstract: An ethylene polymer having small values of Mw/Mn and Mz/Mw, a small proportion of long-chain branches and a high swell ratio and a process for preparing the polymer are disclosed. A solid titanium catalyst component obtained by initially contacting a solid titanium composite containing titanium, magnesium, halogen and a compound having at least two ether linkages present through plural atoms with an organometallic compound and then contacting the resulting product with oxygen is further disclosed. An ethylene polymerization catalyst comprising the above catalyst component and an organometallic compound catalyst component is furthermore disclosed. The ethylene polymer is excellent in moldability, and from this polymer, a molded article which is excellent in rigidity and impact resistance and free from poor appearance can be obtained. By the use of the ethylene polymerization catalyst, an ethylene polymer having excellent properties as mentioned above can be obtained.

Abstract: A solid titanium catalyst component ?Ia! containing magnesium, halogen, titanium and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a catalyst and a prepolymerized olefin-containing catalyst prepared by using the solid titanium catalyst component ?Ia!; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used. A catalyst and a prepolymerized olefin containing catalyst prepared by using a solid titanium catalyst component ?Ib! containing magnesium, halogen, titanium and a specific electron donor (a1), and a compound having at least two ether linkags with a plurality of intermediately existing bonding atoms; a method for preparing a polyolefin wherein said catalyst or prepolymerized olefin containing catayst is used.

Abstract: Process for the preparation of crystalline vinylaromatic polymers with a predominant syndiotactic structure which involves polymerizing vinylaromatic monomers in the presence of a catalytic system comprising: a titanium complex having general formula (I): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4, the same or different, represent a hydrogen atom or a C.sub.1 -C.sub.20 alkyl radical or a C.sub.6 -C.sub.20 arylalkyl or aryl radical, on the condition that at least one of these is different from hydrogen.

Abstract: In accordance with the present invention, there are provided ethylene copolymers composed of structural units (a) derived from ethylene and structural units (b) derived from .alpha.-olefin of 3.about.20 carbon atoms, said ethylene copolymers having?A! a density of 0.85.about.0.92 g/cm.sup.3,?B! an intrinsic viscosity ?.eta.! as measured in decalin at 135.degree. C. of 0.1.about.10 dl/g,?C! a ratio (Mw/Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) as measured by GPC of 1.2.about.4, and?D! a ratio (MFR.sub.10 /MFR.sub.2) of MFR.sub.10 under a load of 10 kg to MFR.sub.2 under a load of 2.16 kg at 190.degree. C. of 8.about.50, and being narrow in molecular weight distribution and excellent in flowability.

Abstract: A process for polymerizing propylene utilizes a metallocene catalyst component of the formula (I) ##STR1## wherein M is a transition metal, R.sup.1 is a C.sub.2-6 hydrocarbon, R.sup.2 is a C.sub.6-16 aryl group, X.sup.1 and X.sup.2 are each a halogen atom and Y is a divalent hydrocarbon or a divalent silicon-containing group. Propylene polymers produced thereby have such properties that the triad tacticity of propylene units is high, the proportion of inversely inserted units based on the 2,1-insertion of propylene monomer is in a specific range and the intrinsic viscosity (.eta.), as measured in decahydronaphthalene at 135.degree. C., is in a specific range.

Abstract: A process for the polymerization of olefinic hydrocarbons is carried out in the presence of a catalyst comprising a catalyst component derived from reacting a compound of the formula Me.sup.1 R.sup.1.sub.n X.sup.1.sub.4-n, a compound of the formula Me.sup.2 R.sup.2.sub.m X.sup.2.sub.z-m, an organocyclic compound having two or more conjugated double bonds and a carrier of inorganic or polymeric material, and a modified organoaluminum compound having Al--O--Al bonds, the resulting polyolefins having a relatively wide molecular weight distribution, a relatively narrow composition distribution and increased bulk density.