Abstract: Catalyst for the polymerization and/or copolymerization of olefins which is obtainable by application to a finely divided inorganic support and concluding calcination at temperatures of from 350 to 1050° C. and has a chromium content of from 0.1 to 5% by weight and a zirconium content of from 0.5 to 10% by weight, in each case based on the element in the finished catalyst, with the molar ratio of zirconium to chromium being from 0.6 to 5.

Abstract: A process for preparing ethylene homopolymers and copolymers in a tubular reactor having two or more polymerization zones at temperatures of between 150° C. and 350° C. and pressures in the range from 500 to 5000 bar, using oxygen as initiator, which comprises using, as molar mass regulator, one or more aliphatic ketones of the formula I, where the variable R1 is a C1-C6-alkyl or C3-C12-cycloalkyl, ethylene homopolymers and copolymers obtainable therefrom and their user for producing injection-molded products in the cosmetics, medical and food sectors are described.

Abstract: Process for preparing a supported catalyst for the polymerization and/or copolymerization of olefins which has a chromium content of from 0.01 to 5% by weight, based on the element, which comprises (a) preparing a homogeneous solution comprising an organic or inorganic chromium compound and at least one further organic or inorganic compound of elements selected from among Mg, Ca, Sr, B, Al, Si, P, Bi, Sc, V, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ru, Rh, Pd, Hf, Ta, W in a protic or aprotic polar solvent, (b) bringing the solution from a) into contact with a finely divided inorganic support to form a catalyst precursor, (c) if appropriate, removing the solvent from the catalyst precursor and (d) calcining the catalyst precursor at temperatures of from 350 to 950° C., preferably 400 to 900° C., under oxidative conditions.

Abstract: The present invention relates to pulverulent solids obtainable by reaction of a metal alkyl compound of a divalent or higher-valent metal and a finely divided support which on its surface bears functional groups which can form a chemical bond between the metal atom of the metal alkyl compound and the surface of the support, wherein the particles of the finely divided support have particle diameters of less than 1000 nm and less than 5% by weight of the metal alkyl compound is extractable in a single extraction of the pulverulent solid with 20 ml of heptane per gram of solid at 50° C. In addition, the invention relates to a process for preparing the pulverulent solids, a catalyst composition for the polymerization of olefins which comprises the pulverulent solids and polymerization processes using the catalyst composition.

Abstract: A process for preparing a broad molecular weight polyethylene carried out in the presence of a catalyst system comprising (i) a solid catalyst component comprising Mg, Ti, halogen, and optionally an internal electron donor compound, and (ii) an Al-alkyl cocatalyst said process comprising at least two step of polymerization (a) and (b), in which: in a first step (a) ethylene is polymerized in the presence of a molecular weight regulator in order to produce a ethylene (co)polymer, and in a further step (b), which is carried out in the presence of an external electron donor compound added to this polymerization step as a fresh reactant, ethylene is copolymerized with an alpha olefin of formula CH2?CHR, in which R is a C1-C20 hydrocarbon group, to produce an ethylene copolymer having a molecular weight higher than that of the copolymer produced in step (b).

Abstract: A fiber for thermal bonding comprising semicrystalline random copolymers of propylene, 1-hexene and optionally another ?-olefin, the amount of 1-hexene being from 0.75 to less 1.52 mol % (i.e. 1.5 to less than 3 wt %) with respect to the total weight of the copolymer. The said copolymers possess a value of melt flow rate (MFR) ranging from 4 to 35 g/10 min and a molecular weight distribution, in terms of the ratio between weight average molecular weight and numeric average molecular weight ( Mw/ Mn), ranging from 4 to 12.

Abstract: The present invention relates to a process for the racemoselective preparation of ansa-metallocene complexes of the formula (I) which comprises reacting a ligand starting compound of the formula (II) with a transition metal compound of the formula (III) (LB)yM1(NR3R4)Xx-1??(III) where R1, R1? are identical or different and are each hydrogen or an organic radical having from 1 to 40 carbon atoms, R2, R2? are identical or different and are each hydrogen or an organic radical having from 1 to 40 carbon atoms, R3 is an organic radical having from 1 to 40 carbon atoms, R4 is hydrogen or an organic radical having from 1 to 40 carbon atoms, T, T? are identical or different and are each a divalent organic group which has from 1 to 40 carbon atoms and together with the cyclopentadienyl ring forms at least one further saturated or unsaturated, substituted or unsubstituted ring system which has a ring size of from 5 to 12 atoms, where T and T? may contain the heteroatoms Si, Ge, N, P, As, Sb, O, S, Se or Te

Abstract: Process for the gas-phase polymerization of one or more alpha-olefins in the presence of a catalyst system, the process comprising: contacting in a continuous way one or more of said alpha-olefins with said catalyst system in a prepolymerization reactor, wherein the reaction is carried out in a liquid medium at a temperature ranging from 23° to 50° C.; feeding in continuous the prepolymer obtained in step a) into a gas-phase reactor having interconnected polymerization zones, where the growing polymer particles flow upward through a first polymerization zone (riser) under fast fluidization or transport conditions, leave said riser and enter a second polymerization zone (downcomer) through which they flow downward under the action of gravity, leave said downcomer and are reintroduced into said riser; wherein the prepolymer obtained from step a) is continuously fed at a section of said riser characterized by an upwardly gas velocity higher than 3.0 m/s.

Abstract: Pulverulent solid which consists essentially of at least one metal alkyl compound bound chemically and/or physically to a finely divided, porous, mechanically stable and chemically inert support, has a proportion by weight of metal alkyl compound of at least 5% by weight, based on the support, and has an angle of repose, determined in accordance with ISO 4324, of up to 48°. The solid allows trouble-free metering as active component into a reactor.

Abstract: A compound of formula (X): wherein R1, R2, equal to or different from each other are hydrogen or a linear or branched saturated or unsaturated C1-C20-alkyl, C3-C20-cycloalkyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radical, optionally containing heteroatoms belonging to groups 13-17 of the Periodic Table of the Elements; or they can form a C4-C7 ring optionally containing O, S, N, P or Si atoms that can bear substituents; R3 is hydrogen or a linear or branched saturated or unsaturated C1-C20-alkyl, C3-C20-cycloalkyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radical, optionally containing heteroatoms belonging to groups 13-17 of the Periodic Table of the Elements; or two adjacent R3 groups can form a C4-C7 ring optionally containing O, S, N, P or Si atoms, wherein said ring can bear substituents; and at least one of R1, R2 or R3 is different from hydrogen.

Abstract: A process for cross-linking an elastomer-containing thermoplastic polyolefin composition comprising the steps of preparing a masterbatch by mixing and/or masticating an elastomeric polyolefin with a cross-linking co-agent, and optionally an additive, in the presence of a thermoplastic polyolefin; then, cooling the masterbatch obtained in the preceding step at least up to the solidification of the thermoplastic polyolefin; and finally mixing and/or masticating the masterbatch, after the cooling step, with a cross-linking agent and optionally an additive.

Abstract: The invention relates to a process for preparing hydrogenated or partially hydrogenated, racemic ansa-metallocene complexes by reacting bridged or unbridged transition metal complexes with alkali metal compounds or alkaline earth metal compounds, heating the resulting reaction mixture to a temperature in the range from ?78 to 250° C. and at least partially hydrogenating the reaction products in the presence of a suitable catalyst, to the corresponding hydrogenated or partially hydrogenated metallocenes and to their use as catalysts or as a constituent of catalysts for the polymerization of olefinically unsaturated compounds or as reagents or catalysts in stereoselective synthesis.

Abstract: Monocyclopentadienyl complexes containing a cyclopentadienyl system comprising at least one fused heterocycle and at least one uncharged donor which can be used in catalyst systems for the polymerization or copolymerization of olefins.

Abstract: A 1-butene/ethylene copolymer having a content of ethylene derived units from 0.1% to 5% by weight in which an ethylene content in the polymer (C2) and a melting point of the polymer (Tm) meet the following relation: Tm<?0.3283C23+4.7184C22?22.454C2+114.

Abstract: A process for producing a polymer of ethylene containing from 0.1 to 99% by mol of one or more derived units of alpha-olefins and optionally from 0 to 5% by mol polyene, comprising contacting ethylene, one or more alpha-olefins and optionally said polyene, in the presence of a catalyst system obtainable by contacting: a) a metallocene compound of formula (I): wherein M is zirconium, hafnium or titanium; X, is a hydrogen atom, a halogen atom, or a hydrocarbon group; R1 is a hydrocarbon group; R2, R3, R4 and R5 are hydrogen atoms, or hydrocarbon groups; R6 is a hydrocarbon group; L is a divalent bridging group, and T is a divalent radical of formula (II) or (III): wherein R8 and R9 are hydrogen or hydrocarbon groups; and b) an alumoxane or a compound capable of forming an alkyl metallocene cation.

Abstract: A process for preparing a catalyst component, comprising a Mg compound a Ti compound and an electron donor compound (ED) selected from alcohol, glycols, esters, ketones, amines, amides, nitrites, alkoxysilanes and aliphatic ethers as essential compounds, comprising two or more steps of reaction involving the use of at least one of said essential compounds as fresh reactant alone or in a mixture in which it constitutes the main component, said process being characterized by the fact that in the last of said one or more reaction steps the essential compound used as a fresh reactant is the ED compound.

Abstract: A process for obtaining 1-butene polymers comprising the step of contacting under polymerization conditions 1-butene and optionally ethylene, propylene or said alpha-olefin, in the presence of a catalyst system obtainable by contacting: a) a metallocene compound of formula (I): wherein: M is an atom of a transition metal belonging to group 3, 4, 5, 6 or to the lanthanide or actinide groups in the Periodic Table of the Elements; p is an integer from 0 to 3; X, is a hydrogen atom, a halogen atom, or a hydrocarbon group; R1 is a hydrocarbon group; R2, R3 and R6 are hydrogen atoms or hydrocarbon groups; R4 and R5 join to form a condensed saturated or unsaturaded 4–7 membered ring; and L is a divalent bridging group; and b) an alumoxane or a compound able to form an alkylmetallocene cation.

Abstract: The present invention relates to a catalyst system for olefin polymerization comprising an organic transition metal compound and, as cocatalyst, an ionic compound made up of anions of the formula (Ia), [Al(OR1)4]???(Ia) where the radicals R1 are identical or different and are each, independently of one another, a radical R2R3(CF3)2, R2 is a carbon or silicon atom and R3 is hydrogen, C1-C20-alkyl, C1-C20-fluoroalkyl, C6-C20-aryl, C6-C20-fluoroaryl, C7-C40-arylalkyl, C7-C40-fluoroarylalkyl, C7-C40-alkylaryl, C7-C40-fluoroalkylaryl or an SiR43 group, where R4 may be identical or different and is each C1-C20-alkyl, C1-C20-fluoroalkyl, C6-C20-aryl, C6-C20-fluoroaryl, C7-C40-arylalkyl, C7-C40-fluoroarylalkyl, C7-C40-alkylaryl or C7-C40-fluoroalkylaryl, and Lewis-acid cations or Brönsted acids as cations. In addition, the invention relates to the process for preparing such a catalyst system and to a process for the polymerization of olefins in which this catalyst system is used.

Abstract: Articles, in particular non-pressure mono- or multi-layer pipes, prepared by extrusion, molding and combination thereof, comprising a heterophasic polyolefin composition comprising (1) 65-95% of a crystalline propylene polymer insoluble in xylene at ambient temperature in an amount over 85% and having a polydispersity index ranging from 4 to 13 and an intrinsic viscosity value ([?]1) of over 2.2 dl/g, and (2) 5-35% of an elastomeric olefin polymer of ethylene with a C3-C10 ?-olefin having an ethylene content ranging from 15 to 85% and an intrinsic viscosity value ([?]2) of at least 1.4 g/ml. The [?]1/[?]2 ratio ranging from 0.45 to 1.6. The articles typically have modulus of elasticity in tension higher than 2000 MPa. The invention also relates to the said heterophasic polyolefin composition and an extrusion process for producing the said articles.

Abstract: Polyolefin compositions comprising (percent by weight): 1) 55-90% of a crystalline propylene homopolymer or copolymer containing up to 15% of ethylene and/or C4-C10 ?-olefin(s) and having values of MFR equal to or higher than 25 g/10 min; 2) 10-45% of a copolymer of ethylene with one or more C4-C10 ?-olefin(s) containing from 10 to 40% of said C4-C10 ?-olefin(s); said compositions having values of MFR equal to or higher than 20 g/10 min, a total content of ethylene of 20% or more, a total content of C4-C10 ?-olefin(s) of 4.5% or more, a ratio of the total content of ethylene to the total content of C4-C10 ?-olefin(s) of 2.3 or more, a total fraction soluble in xylene at room temperature of less than 18 wt % and an intrinsic viscosity value of the fraction soluble in xylene at room temperature of 1.7 dl/g or less.