Abstract: A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa·s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.

Abstract: A pressure pipe resin is disclosed comprising from 90 to 99.9 wt %, based on the total weight of the resin, of a polyethylene, and from 0.1 to 10 wt %, based on the total weight of the blend, of an ionomer.

Abstract: A polyethylene resin comprising a blend of from 35 to 49 wt % of a first polyethylene fraction of high molecular weight and 51 to 65 wt % of a second polyethylene fraction of low molecular weight, the first polyethylene fraction comprising a linear low density polyethylene having a density of up to 0.928 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3, and an MI2 of greater than 100 g/10 min, and the polyethylene resin, having a density of greater than 0.951 g/cm3 and an HLMI of from 1 to 100 g/10 min.

Abstract: A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa.s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.

Abstract: A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of great 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa.s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.

Abstract: A polyethylene resin comprising a blend of from 35 to 49 wt % of a first polyethylene fraction of high molecular weight and 51 to 65 wt % of a second polyethylene fraction of low molecular weight, the first polyethylene fraction comprising a linear low density polyethylene having a density of up to 0.928 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3, and an MI2 of greater than 100 g/10 min, and the polyethylene resin, having a density of greater than 0.951 g/cm3 and an HLMI of from 1 to 100 g/10 min.

Abstract: A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa.s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.

Abstract: Novel asymmetric silicon-bridged metallocenes useful as catalysts in the polymerization of olefins and process for preparing said metallocenes.

Abstract: Novel silylene or ethylene bis(tetrahydrofluorenyl)metallocenes are synthesized and used as olefin polymerization catalysts.

Abstract: Novel asymmetric silicon-bridged metallocenes useful as catalysts in the polymerization of olefins and process for preparing said metallocenes.

Abstract: Process for the preparation of a catalyst for the polymerization of alpha-olefins involves contacting a porous polyolefin support with a solution containing an activator (ii) to form a suspension. The suspension is evaporated in a reactor fitted with a stirrer comprising a scraping element. The scraping element follows the walls of the reactor at a distance from 2 to 200 times the mean particle diameter of the support. The catalyst includes a compound of a transition metal (i) from Groups 4 to 6 of the Periodic Table and at least one optionally substituted cyclopentadiene ligand and an aluminoxane activator (ii). The aluminoxane activator (ii) and transition metal compound are supported on the porous polyethylene support (iii). The walls of the reactor show no traces of crusting.

Abstract: Disclosed is for the preparation of a catalytic composition for the polymerization of alpha-olefins. The catalyst comprises a compound of a transition metal (i) of Groups 4 to 6 of the Periodic Table, containing at least one possibly substituted cyclopentadiene ligand, and an activator (ii) chosen from aluminoxanes and ionizing agents supported on a support (iii) consisting of porous particles of polyolefin(s). Preparation includes a preliminary polymerization which includes contact with an alpha-olefin, under polymerizing conditions, in a diluent whose kinematic viscosity, measured at 20° C., is from 3 to 3000 cSt (centistokes) from 3 to 3000 mm2/s, such as mineral oil which may be derived from coal tars and petroleum fractions, to form from 0.01 to 50 g of polyolefin per g of catalyst containing compounds (i), (ii) and (iii).

Abstract: Asymmetric silicon-bridged metallocenes represented by the general formula: wherein M represents a transition metal selected from Ti, Zr and Hf. X and X′ represent a halogen atom, R1, R2, R3 represent alkyl groups containing 1 or 2 carbon atoms or hydrogen atoms, providing that at least two of R1, R2, R3 are alkyl groups, and R4 and R5 represent alkyl or aryl group containing from 1 to 10 carbon atoms. A process for their preparation and polymerization of olefins in the presence of the asymmetric silicon-bridged metallocenes are disclosed.

Abstract: Novel asymmetric ethylene-bridged metallocenes useful as catalysts in the polymerization of olefins and process for preparing said metallocenes.The novel metallocenes are represented by the general formula: ##STR1## wherein M represents a transition metal selected from titanium, zirconium and hafnium and X and X' represent a halogen atom. Preferably, the transition metal is Zr and the halogen atoms are both chlorine.

Abstract: Catalytic system which can be used for the polymerisation of .alpha.-olefins comprising:a solid based on complexed titanium trichloride of .delta. crystalline form;an organoaluminium compound;an organic oxygenated silicon compound; characterised in that the organoaluminium compound is a non-halogenated compound.

Abstract: Propylene block copolymer containing per:100 parts by weight of a polymer (a) of propylene chosen from homopolymers and copolymers of propylene not containing more than 6% by weight of ethylene and/or of an alpha-olefin having from 4 to 6 carbon atoms,from 1 to 100 parts by weight of a polymer (b) of ethylene chosen from homopolymers and copolymers of ethylene not containing more than 90% by weight of propylene and/or of another alpha-olefin having from 4 to 6 carbon atoms,the said block copolymer additionally containing from approximately 0.001 to approximately 20% by weight of .alpha.,.omega.-diene-derived monomer units with respect to the total weight of the block copolymer.