Abstract: A solid catalyst component for the (co)polymerization of ?-olefins having general formula (I): ZrnMAlxClyMgp??(I) wherein: M represents titanium (Ti), vanadium (V), or mixtures thereof; n is a number ranging from 0.01 to 2; x is a number ranging from 0.1 to 4; y is a number ranging from 5 to 53; p is a number ranging from 0 to 15; obtained by means of a process comprising putting at least one zirconium arene in contact with at least one metal compound and, optionally, with at least one compound of magnesium. Said solid catalyst component can be advantageously used as a solid component in a catalyst for the (co)polymerization of ?-olefins. Said catalyst can be advantageously used in a process for the (co)polymerization of ?-olefins.

Abstract: Metal alkyl-arene having general formula (I) or (Ia): M (?6-arene)2AlqXrRs (I) M (?6-arene)AlqXrRs (Ia) wherein: —M represents zirconium (Zr), hafnium (Hf), or mixtures thereof, preferably zirconium; —arene represents a benzene, or a benzene 10 substituted with from 1 to 6 linear or branched C1-C6 alkyl groups, or mixtures thereof; —X represents a halogen atom selected from chlorine, bromine, fluorine, iodine, preferably chlorine; —R represents a linear or branched C1-C15 alkyl group; —q is a number ranging from 2 to 6, preferably 3 for a metal alkyl-arene having general formula (I), 2 for a metal alkyl-arene having general formula (Ia); —r is a number ranging from 1 to 20, preferably 9 for a metal alkyl-arene having general formula (I), 6 for a metal alkyl-arene having general formula (Ia); —s is a number ranging from 1 to 6, preferably 2. Said metal alkyl-arene can be advantageously used for the preparation of solid components of catalysts for the (co)polymerization of ?-olefins.

Abstract: A solid catalyst component for the (co)polymerization of ?-olefins having general formula (I): ZrnMAlxClMgp (I) wherein: M represents titanium (Ti), vanadium (V), or mixtures thereof; n is a number ranging from 0.01 to 2; x is a number ranging from 0.1 to 4; y is a number ranging from 5 to 53; p is a number ranging from 0 to 15; obtained by means of a process comprising putting at least one zirconium arene in contact with at least one metal compound and, optionally, with at least one compound of magnesium. Said solid catalyst component can be advantageously used as a solid component in a catalyst for the (co)polymerization of ?-olefins. Said catalyst can be advantageously used in a process for the (co)polymerization of ?-olefins.

Abstract: Metal alkyl-arene having general formula (I) or (Ia): M (?6-arene)2Al1XrRs (I) M (?6-arene)AlqXrRs (Ia) wherein: —M represents zirconium (Zr), hafnium (Hf), or mixtures thereof, preferably zirconium; —arene represents a benzene, or a benzene 10 substituted with from 1 to 6 linear or branched C1-C6 alkyl groups, or mixtures thereof; —X represents a halogen atom selected from chlorine, bromine, fluorine, iodine, preferably chlorine; —R represents a linear or branched C1-C15 alkyl group; —q is a number ranging from 2 to 6, preferably 3 for a metal alkyl-arene having general formula (I), 2 for a metal alkyl-arene having general formula (Ia); —r is a number ranging from 1 to 20, preferably 9 for a metal alkyl-arene having general formula (I), 6 for a metal alkyl-arene having general formula (Ia); —s is a number ranging from 1 to 6, preferably 2. Said metal alkyl-arene can be advantageously used for the preparation of solid components of catalysts for the (co)polymerization of ?-olefins.

Abstract: An organometallic composition which can be used as activating component in a metallocene catalyst for the (co)polymerization of ?-olefins, comprises: (A) a fluorinated di-unsaturated cyclic compound, having a relatively acid hydrogen atom, (B) an organometallic compound sufficiently basic to react with the acid hydrogen of the above compound (A), and (C) a polar aprotic organic compound, not containing metallic atoms, having a dielectric constant, in the pure state, equal to or greater than 2, and a weak coordinating capacity. Said composition allows a metallocene catalytic system of the ionic type to be obtained, with a high activity in the (co)polymerization of olefins and a reduced content of metallic residue in the polymeric product thus obtained.

Abstract: An organometallic composition which can be used as activating component in a metallocene catalyst for the (co)polymerization of &agr;-olefins, comprises: (A) a fluorinated di-unsaturated cyclic compound, having a relatively acid hydrogen atom, (B) an organometallic compound sufficiently basic to react with the acid hydrogen of the above compound (A), and (C) a polar aprotic organic compound, not containing metallic atoms, having a dielectric constant, in the pure state, equal to or greater than 2, and a weak coordinating capacity. Said composition allows a metallocene catalytic system of the ionic type to be obtained, with a high activity in the (co)polymerization of olefins and a reduced content of metallic residue in the polymeric product thus obtained.

Abstract: A catalyst for the (co)polymerization of ethylene is obtained by a process comprising the contact of the following components (A), (B), (C) and (D) in the respective molar ratios (1):(0.5-2):(0-25):(0-15):(A): a bivalent arene of titanium having the formulaTi (.eta..sup.6 -arene)(AlR.sub.x X.sub.4-x).sub.2 ;wherein: "arene" indicates benzene, or benzene substituted with from 1 to 6 C.sub.1 -C.sub.10 alkyl groups;each X independently represents a chlorine, bromine or fluorine atom;R is a C.sub.1 C.sub.10 alkyl group, linear or branched; "x" is a number varying from 0.5 to 2.

Abstract: A procedure is described for the preparation of a vanadium bis-arene, [V(arene).sub.2 ], starting from vanadium oxychloride, aluminium metal, aluminium trichloride and an arene, wherein:(a) vanadium oxychloride (VOCl.sub.3), active aluminium metal, and aluminium trichloride are put in contact with each other, in a liquid arene, to transform the vanadium oxychloride into the complex compound [V(arene).sub.2 ].sup.+ [AlCl.sub.4 ].sup.- ;(b) a liquid cyclic or acyclic or acyclic ether is added to the reaction product of step (a) to reduce [V(arene).sub.2 ].sup.+ to [V(arene).sub.2 ]; and(c) the vanadium bis-arene [V(arene).sub.2 ] is recovered from the reacton product of step (b).The vanadium bis-arenes thus obtained are use in the preparation of catalysts for the polymerization of olefins.

Abstract: Vanadium-arenes[V(arene).sub.2 ]wherein "arene" means benzene or mono-, di- or poly-(C.sub.1 -C.sub.5)-alkyl-substituted benzene, are prepared by means of a process which comprises:(a) forming a complex:[V(arene).sub.2 ](+).AlCl.sub.4 (-)by reacting vanadium trichloride, aluminum metal and aluminum trichloride with one another, by operating in the presence of the selected arene;(b) treating the so obtained complex with an either cyclic or acyclic, liquid aliphatic ether to obtain the reduction of [V(arene).sub.2 ](+) to [V(arene).sub.2 ]; and(c) recovering the so separated vanadium-arene.The vanadium-arenes are useful in the preparation of catalysts for olefin polymerization.

Abstract: A solid catalyst component for the polymerization of ethylene and the copolymerization of ethylene with C.sub.3 -C.sub.10 alpha-olefins, contains titanium, vanadium and chlorine, is substantially definable by the formula (in atomic proportions):V (1), Ti (n), Cl (4n)where n varies from 1 to 3, and is prepared by reacting titanium tetrachloride with a vanadium arene [V.degree.(arene).sub.2 ] (arene=benzene or mono-, di- or tri-alkyl substituted benzene) in accordance with the equation:V.degree.(arene).sub.2 +nTiCl.sub.4 .fwdarw.VTi.sub.n Cl.sub.4n +2 arenepossibly followed by treatment with an alkyl aluminum chloride. This catalyst component, when associated with a trialkyl aluminium, is highly active in the production of ethylene polymers and copolymers by low temperature, low pressure methods in suspension, or by high temperature, high pressure methods conducted in a tubular reactor or pressure vessel, or by high temperature methods conducted in solution.

Abstract: Vanadium-arenes [V(arene).sub.2 ] (arene=benzene or mono-, di-, or poly-alkyl-substituted benzene) are obtained, with a high yield, by means of the reduction of a vanadium-arene iodide with zinc, manganese or iron in metal form, or with cobalt di-(cyclopentadienyl).Vanadium-arenes are useful in the preparation of catalyst components active in ethylene polymerization, or in the copolymerization of ethylene in an alpha-olefin.