Abstract: A process is described for the hydrogenation of olefin double bonds present in polymers and copolymers of conjugated dienes, which comprises putting the above polymer or copolymer of conjugated dienes in contact with hydrogen in an inert solvent, in the presence of a catalytic system, characterized in that the above catalytic system essentially consists of one or more titanium compounds selected from those having general formula (I) wherein: M is selected from Ti(III) and Ti(IV) and their mixtures.

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 process is described for the preparation of elastomeric EP(D)M copolymers and terpolymers, characterized in that it is carried out in the presence of metallocene compounds of general formula (I) having a racemic stereoisomerism.

Abstract: Titanium complex having general formula (1) (RCOO)nTiXp wherein R is a monofunctional hydrocarbyl radical having from 1 to 20 carbon atoms and a number of halogen atoms, selected from fluorine, chlorine and bromine, preferably chlorine, ranging from 1 to 6; X is chlorine, bromine or a beta-dicarbonyl group such as acetylacetone (AcAc), formylacetone, benzoylacetone, dibenzoylmethane; p+n=2, 3, 4, preferably p+n=3; n is greater than or equal to 1. The preparation of the above complex and its use in the co- and ter-polymerization of &agr;-olefins, are also described.

Abstract: A process is described for the hydrogenation of olefin double bonds present in polymers and copolymers of conjugated dienes, which comprises putting the above polymer or copolymer of conjugated dienes in contact with hydrogen in an inert solvent, in the presence of a catalytic system, characterized in that the above catalytic system essentially consists of one or more titanium compounds selected from those having general formula (I) 1

Abstract: Catalytic composition for the (co)polymerization of ethylene and other &agr;-olefins, including a metallocene complex of a metal M of group 4 of the periodic table or the product obtainable from the same combined with a suitable activator, wherein said metallocene complex includes at least one cyclopentadienyl group and at least one unsaturated hydrocarbyl organic group bonded to the metal M, having the following formula (I):

Abstract: A metallocene compound of a metal M of group 4 in the table of elements, comprising a cyclopentadienyl group and at least one oligomeric group R′ bonded to M, having the following formula (II):

Abstract: A description follows of ligands having general formula (I) wherein R1, R2, R3, R4, R5, and R6, the same or different, are selected form hydrogen, halogen, C1-C10 alkyl, C6-C15 aryl optionally halogenated, or adjacent pairs of Ri groups (with i ranging from 1 to 6) are bound to each other to give cyclic hydrocarbon structures condensed with the thiophene or pyridine ring: R7 is selected from H, C1-C10 alkyl, C6-C15 aryl: R8 is selected from C1-C10 alkyl and C6-C15 aryl. The complexes of the above ligands with transition metals are also described.

Abstract: Complex catalysts based on a metal of group VIII complexed with suitable ligands, particularly active in the homopolymerization of ethylene and in its copolymerization with another unsaturated monomer of the vinylic and acrylic type.

Abstract: Allyl polyalkylcyclopentadienyl complex of a metal of group 4 of the periodic table, and its use in the preparation of a catalytic composition for the (co) polymerization of &agr;-olefins. said complex is advantageously stable in solution and rapidly forms catalytic compositions with a high activity without the necessity of effecting alkylating pretreatment.

Abstract: Process for the selective oligomerization of ethylene to give &agr;-olefins essentially consisting of C4 to C8, character in that it is carried out in the presence of a catalytic system comprising the complex having general formula (II): (L)M(Y)n wherein L represents the ligand having general formula (I) M represents a transition metal; Y is selected from groups of an anionic nature bound to the metal as anion in ionic couple or with a covalent bond of the “&sgr;” type.

Abstract: New polycyclic cyclopentadiene compounds having the formula (II) wherein the various substituents and symbols R1, R2, R3, R4, R5, R6, R7, Z1 and Z2 and “n” have the meaning specified in the description. These compounds can form metallocene complexes with transition metals, which have shown unusual properties in the (co)polymerization of ethylene and alpha-olefins in general.

Abstract: An organometallic composition of a reaction product of a fluorinated organic compound of formula (I): wherein R1 to R8 are as described in the specification, m is 0 or 1; and an organometallic compound of formula (II): M′RnX(p−n)  (II) wherein M′, R, X, n and p are as described in the specification; a polymerization catalyst composition using the above organometallic composition and a metallocene complex a method of making the catalyst composition and using the catalyst composition to polymerize &agr;-olefins.

Abstract: Vanadium complex having general formula (I) (RCOO)nVXpLm  (I) wherein R is a monofunctional hydrocarbon radical having from 1 to 20 carbon atoms and from 1 to 6 halogen atoms, selected from chlorine and bromine, preferably chlorine; X is chlorine or bromine, preferably chlorine; L is an electron donor; p+n=3, 4 or 5, preferably=3; n is greater than or equal to 1; m is between 0 and 3. The preparation of the above complex is also described together with its use in the (co)polymerization of &agr;-olefins.

Abstract: A process is described for the preparation of compounds having the formula (I) C6F4HX, wherein X is Br or Cl, which comprises reacting tetrafluorobenzene with a halogen in the presence of a Lewis acid catalyst.

Abstract: Process for the preparation of 1-hexane consisting in effecting the oligomerization of ethylene in the presence of a catalyst comprising a vanaduim complex having the formula: (arene)2 VX wherein the term arene represents benzene or mono-, di-, or tri-alkylsubstituted benzene, V is a vanaduim ion with a low wxidation state, and X is an anion selected from non-coordinated anions such as B(Ar)4—, AlCl4—, carboxylates and sulfonates.

Abstract: A “bridged” bis-cyclopentadienyl complex which can be advantageously used for the formation of a catalytic system active in the (co)polymerization of ethylene and other &agr;-olefins is represented by means of the following formula (II): wherein: M represents a metal selected from titanium, zirconium or hafnium; A′ and A″ each independently represent an anion containing an &eegr;5-cyclopentadienyl ring coordinated to M; R′ or R″ each independently represents a group of an anionic nature &sgr;-bound to the metal M; B represents an unsaturated bivalent organic residue having from 1 to 30 carbon atoms, bound, respectively, to the ring of group A′ and to the —CH2-methylene group by means of carbon atoms.

Abstract: A “bridged” bis-cyclopentadienyl complex which can be advantageously used for the formation of a catalytic system active in the (co)polymerization of ethylene and other a-olefins is represented by means of the following formula (II): 1

Abstract: A catalytic composition effective in the selective hydrogenation of olefinic double bonds, comprising the reaction product between: (A) at least one complex of a transition metal having the following general formula (I): M(R1)(R2)(R3)(R4)  (I)  wherein: M is selected from titanium and zirconium, preferably titanium; each of the radicals R1, R2, R3 or R4, independently, represents an organic or inorganic group of an anionic nature &sgr;-bound to M, on the condition that at least one, and preferablyat at least two, of these radicals is an organic group; and (B) at least one organometallic compound of magnesium having the following formula (II): Mg(R5)n(R6)(2−n)  (II)  wherein: R5 or R6 each independently represent an aliphatic or aromatic hydrocarbon group having from 1 to 20 carbon atoms, and “n” is a decimal number between 0 and 2.0.

Abstract: A “bridged” bis-cyclopentadienyl complex which can be advantageously used for the formation of a catalytic system active in the (co)polymerization of ethylene and other &agr;-olefins is represented by means of the following formula (II): wherein: M represents a metal selected from titanium, zirconium or hafnium; A′ and A″ each independently represent an anion containing an &eegr;5-cyclopentadienyl ring coordinated to M; R′ or R″ each independently represents a group of an anionic nature a-bound to the metal M; B represents an unsaturated bivalent organic residue having from 1 to 30 carbon atoms, bound, respectively, to the ring of group A′ and to the —CH2— methylene group by means of carbon atoms.