Abstract: Process for the preparation of an ethylene copolymer composition having a polydispersity index Mw/Mn of from 3 to 100, comprising a) feeding ethylene to at least one polymerization reactor; b) performing in the at least one polymerization reactor an oligomerization of ethylene in the presence of an oligomerization catalyst component (C) to produce comonomer; c) performing simultaneously in the at least one polymerization reactor polymerization reactions in the presence of catalyst components (A) and (B) producing, respectively, a first and a second polyethylene fraction, wherein the weight average molecular weight Mw of the first polyethylene fraction produced by catalyst component (A) is less than the Mw of the second polyethylene fraction produced by catalyst component (B) and the comonomer incorporation ability of catalyst component (B) is higher than the comonomer incorporation ability of catalyst component (A); and d) withdrawing the ethylene copolymer composition from the polymerization reactor.

Abstract: Process for preparing ethylene homopolymers or copolymers in the presence of free-radical polymerization initiator and at least one chain transfer agent at pressures in the range of from 110 MPa to 350 MPa and temperatures in the range of from 100° C. to 350° C. in a tubular reactor with at least two reaction zones having different concentrations of the chain transfer agent, wherein the concentration of the chain transfer agent in the first reaction zone is less than 70% of the concentration of the chain transfer agent in the reaction zone with the highest concentration of the chain transfer agent, ethylene homopolymers or copolymers obtainable by such a process, the use of the ethylene homopolymers or copolymers for extrusion coating and a process for extrusion coating a substrate selected from the group consisting of paper, paperboard, polymeric film, and metal, with such ethylene homopolymers or copolymers.

Abstract: A novel gas phase polymerisation method is devised, for polymerisation of low and ultralow density polyethylene.

Abstract: Method to improve the barrier properties of composite gas cylinders and high pressure gas cylinder having enhanced barrier properties. The instant invention pertains to a new method for improving the barrier properties of composite gas cylinders for the storage of gas, by wrapping the outer surface of a composite gas cylinder with a plastic film comprising a barrier material in a winding process. The composite gas cylinder comprises an inner liner made of polyolefin and an outer fibre-reinforced, pressure supporting layer. The barrier material may comprise polyamide, polyester, halogen substituted polymer, EVOH or a metallization. The invention pertains also to a high pressure composite gas cylinder having enhanced barrier properties and its use as a fuel tank in gas driven automotive vehicles equipped with a combustion engine.

Abstract: Method to improve the barrier properties of composite gas cylinders and high pressure gas cylinder having enhanced barrier properties The instant invention pertains to a new method for improving the barrier properties of composite gas cylinders for the storage of gas, by sheathing the outer surface of a composite gas cylinder with a tubular plastic film comprising a barrier material and shrinking it by heat treatment to approach a strong connection. The composite gas cylinder comprises an inner liner made of polyolefin and an outer fibre-reinforced, pressure supporting layer. The barrier material may comprise polyamide, polyester, halogen substituted polymer, EVOH or a metallization. The invention pertains also to a high pressure composite gas cylinder having enhanced barrier properties and its use as a fuel tank in gas driven automotive vehicles equipped with a combustion engine.

Abstract: An ethylene copolymer, a catalyst system suitable to prepare the ethylene copolymer, and a process to prepare such ethylene copolymer are described. The use of the ethylene copolymer as impact modifier in polyethylene and as compatibilizer in a polymer blend are also described. The ethylene copolymer has a density from 0.855 g/cm3 to 0.910 g/cm3, a polydispersity Mw/Mn lower than 3.5, comprises at least one first ethylene polymer component and at least one second ethylene polymer component having different comonomer contents so as to show at least two predetermined CRYSTAF peak temperatures.

Abstract: Polyethylene which comprises ethylene homopolymers and copolymers of ethylene with ?-olefins and has a molar mass distribution width Mw/Mn of from 6 to 100, a density of from 0.89 to 0.97 g/cm3, a weight average molar mass Mw of from 5000 g/mol to 700 000 g/mol and has from 0.01 to 20 branches/1000 carbon atoms and at least 0.5 vinyl groups/1000 carbon atoms, wherein the 5-50% by weight of the polyethylene having the lowest molar masses have a degree of branching of less than 10 branches/1000 carbon atoms and the 5-50% by weight of the polyethylene having the highest molar masses have a degree of branching of more than 2 branches/1000 carbon atoms, a process for its preparation, catalysts suitable for its preparation and also fibers, moldings, films or polymer blends in which this polyethylene is present.

Abstract: A propylene polymer composition comprising (percent by weight referring to the sum of A+B): A) 60%-90% of a crystalline propylene copolymer containing from 1.0% to 5.0% of ethylene derived units; B) 10%-40% of a copolymer of propylene with from 18% to 32% of ethylene derived units, said propylene polymer composition having a melt flow rate value according to ISO 1133 (230° C., 2.16 kg) of from 1.0 to 2.0 g/10 min.

Abstract: Process for the preparation of a multimodal polyolefin polymer at temperatures of from 40 to 150° C. and pressures of from 0.

Abstract: The present invention relates to a slurry process for preparing an ethylene polymer having a melt flow ratio F/P, according to ASTM 1238, of higher than 25, carried out in two or more stages of polymerization at temperatures in the range from 60 to 120° C., in which at least two of the said two or more polymerization stages are carried out under different concentration of a molecular weight regulator, said process being carried out in the presence of a catalyst system comprising the product obtained by contacting (A) a solid catalyst component comprising Ti, Mg, halogen, and having a porosity (PF), measured by the mercury method and due to pores with radius equal to, or lower than, 1 ?m of at least 0.3 cm3/g and a surface area determined by BET method, of lower than 100 m2/g, and (B) of an organoaluminum compound.

Abstract: Methods of preparing silica-supported catalysts useful for olefin polymerization are described. The catalysts comprise a metallocene complex. An activator mixture made from a boron acid compound and methylalumoxane is combined with either: (i) the metallocenecomplex, followed by calcined or chemically treated silica to give a supported catalyst; or (ii) calcined or chemically treated silica, followed by the metallocenecomplex to give a supported catalyst. The methods provide active supported catalysts.

Abstract: Method for activation of chromium containing catalyst precursor for polymerization and improved polymerization catalyst resulting The instant invention relates to an activation of a polymerization catalyst precursor by heat treatment comprising a support material and a catalyst precursor deposited thereon in a fluidized bed activator and to the use of the activated polymerization catalyst in the manufacture of polyolefins. The Method is performed in a cylindrical activator (1) arranged vertically comprising tubular activator walls, a fluidization gas inlet (2) near the bottom, a fluidization gas outlet (3) near the top and a heat exchange jacket (4) outside the tubular activator walls, wherein the heating jacket covers the complete outer surface of the walls of the activator. The catalyst prepared by that method is improved with respect to its minor content of impurities and causes less interruptions during gas-phase polymerization or slurry polymerization either in stirred vessel or loop.

Abstract: A novel polyethylene formed by Ziegler catalyst is devised, for use in blow moulding.

Abstract: A process for the production of a corona-treated polyolefin film comprising the gas-phase polymerization of one or more ?-olefins in the presence of a polymerization catalyst and an antistatic agent having a molecular weight higher than 500, said antistatic agent being fed at any stage of the polymerization process in an amount from 30 to 500 ppm weight based on the weight of the produced polyolefin.

Abstract: Thermoset polyolefin elastomer obtained by static curing with water a silane-grafted thermoplastic heterophasic polyolefin composition (I) having a flexural modulus equal to or lower than 150 MPa, and comprising: (a) a crystalline propylene homopolymer or copolymer of propylene with up to 15% by weight of ethylene or other alpha-olefin comonomer(s), or their combinations, and (b) a copolymer or a composition of copolymers of ethylene with other alpha-olefins containing from 15% by weight to less then 40% by weight of ethylene; said thermoset polyolefin elastomer having a compression set value of from 30 to 65%, a ratio of elongation at break to compression set values of above 8, and hardness shore A values below 90.

Abstract: The invention relates to a bimodal or multimodal polyethylene which comprises ethylene homopolymers and/or copolymers of ethylene with ?-olefins, has a polydispersity index Mw/Mn of the low molecular weight component of less than 10 and can be prepared using a polymerization catalyst based on a Ziegler component and a late transition metal component having a tridentate ligand which bears at least two ortho,ortho-disubstituted aryl radicals and also a catalyst system and a process for preparing the polyethylene and also fibers, moldings, films and polymer blends comprising this material.

Abstract: A method for feeding an antistatic compound to a polymerization reactor comprising the steps of: a) dispersing, under mixing conditions, a catalyst powder and an antistatic compound in an oil, so as to form a suspension of catalyst powder and antistatic compound in said oil; b) successively adding, under mixing conditions, a molten thickening agent to said suspension from step a), while maintaining said suspension at a temperature such that said thickening agent solidifies on contact with said suspension; c) transferring the product obtained from b) to a polymerization reactor.

Abstract: A method for transitioning from a Ziegler-Natta to a Phillips catalyst system for the olefin polymerization reaction in one reactor, preferably a gas phase reactor, is described. The method comprises the steps of a) discontinuing a first olefin polymerization reaction performed in the presence of the Ziegler-Natta catalyst system; b) performing a second olefin polymerization reaction in the presence of a further catalyst system comprising catalyst components (A) and (B) producing, respectively, a first and a second polyolefin fraction, wherein the Mw of the first polyolefin fraction is less than the Mw of the second polyolefin fraction and the initial activity of catalyst component (A) exceeds the initial activity of catalyst component (B); and c) performing a third olefin polymerization reaction the presence of the Phillips catalyst system.

Abstract: The present invention relates to non-symmetrical organometallic transition metal compounds of the compound of the formula (I) where R8 and R9 are identical or different and each an substituted or unsubstituted organic radical having from 1 to 40 carbon atoms, catalyst systems comprising at least one of the organometallic transition metal compounds of the present invention and a process for preparing polyolefins by polymerization or copolymerization of at least one olefin in the presence of one of the catalyst systems of the present invention.

Abstract: The present invention relates to a new hybrid catalyst system for the polymerization of olefins and to a polymerization process carried out in the presence of said catalyst. The new hybrid catalyst system comprises a tridendate iron compound and a zirconocene having a bridge of at least three carbon atoms connecting two indenyl ligands.