Abstract: A resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid). The invention also covers a process for preparing a resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid) by (i) blending a poly(hydroxy carboxylic acid) with carbon nanotubes to form a composite (ii) blending the composite with a polyolefin. The use of poly(hydroxy carboxylic acids) as a compatibilizer to blend carbon nanotubes into polyolefins is also claimed.

Abstract: A resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid). The invention also covers a process for preparing a resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid) by (i) blending a poly(hydroxy carboxylic acid) with carbon nanotubes to form a composite (ii) blending the composite with a polyolefin. The use of poly(hydroxy carboxylic acids) as a compatibilizer to blend carbon nanotubes into polyolefins is also claimed.

Abstract: A resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid). The invention also covers a process for preparing a resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid) by (i) blending a poly(hydroxy carboxylic acid) with carbon nanotubes to form a composite (ii) blending the composite with a polyolefin. The use of poly(hydroxy carboxylic acids) as a compatibiliser to blend carbon nanotubes into polyolefins is also claimed.

Abstract: The present invention discloses a process for preparing polyethylene resins in a double loop reactor wherein the catalyst system comprises a bis-tetrahydroindenyl and a bis-indenyl catalyst component deposited on the same support. It also discloses the polyethylene resins obtained by the process and their use to prepare films having a good compromise of haze, processing and mechanical properties.

Abstract: A resin composition comprising a polyolefin, a nanoclay and poly(hydroxy carboxylic acid). The invention also covers a process for preparing a resin composition comprising a polyolefin, a nanoclay and poly(hydroxy carboxylic acid) by (i) blending a poly(hydroxy carboxylic acid) with a nanoclay to form a composite (ii) blending the composite with a polyolefin. The use of poly(hydroxy carboxylic acids) as a compatibiliser to blend nanoclays into polyolefins is also claimed.

Abstract: A resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid). The invention also covers a process for preparing a resin composition comprising a polyolefin, carbon nanotubes and poly(hydroxy carboxylic acid) by (i) blending a poly(hydroxy carboxylic acid) with carbon nanotubes to form a composite (ii) blending the composite with a polyolefin. The use of poly(hydroxy carboxylic acids) as a compatibiliser to blend carbon nanotubes into polyolefins is also claimed.

Abstract: The invention relates to a long chain branched medium and low density polyethylene having a combination of the following properties: a) a density of from 0.910 to 0.945 g/cm3; b) an HLMI of from 2 to 150 dg/min and an MI2 of from 0.01 to 2 dg/min; c) a polydispersity index (PDI) Mw/Mn of at least 7, wherein Mw is the weight average molecular weight and Mn is the number average molecular weight of the polyethylene; and d) and a minimum amount of long chain branching measured by a value selected from one of grheo and LCBI. The invention also relates to a process for obtaining said polyethylene comprising the following steps: a) injecting ethylene, one or more alpha-olefinic comonomers comprising 3 to 10 carbon atoms and an activated chromium-based catalyst into a gas phase polymerisation reactor; b) copolymerising said ethylene and comonomer in said reactor in the gas phase; and c) retrieving an ethylene copolymer having a density of from 0.910 to 0.

Abstract: The present invention discloses a process for preparing polyethylene resins in a double loop reactor wherein the catalyst system comprises a bis-tetrahydroindenyl and a bis-indenyl catalyst component deposited on the same support. It also discloses the polyethylene resins obtained by the process and their use to prepare films having a good compromise of haze, processing and mechanical properties.

Abstract: The present invention concerns a catalyst for the production of high density polyethylene, by homopolymerising ethylene or copolymerising ethylene and an alpha-olefinic comonomer comprising 3 to 10 carbon atoms, prepared by the steps of: a) selecting a silica support with a specific surface area larger than 300 m2/g; b) treating the silica support with a titanium compound, in order to introduce titanium into the support, or with an aluminium compound, in order to introduce aluminum into the support; c) either treating the titanated silica support with an aluminum compound, in order to introduce aluminum into the titanated silica support, or treating the aluminated silica support with a titanium compound, in order to introduce titanium into the aluminated silica support; d) depositing a chromium compound on the titanated and aluminated silica support to form a catalyst; e) activating the catalyst of step d) under air in a fluidised bed at a temperature of from 600 to 800° C.

Abstract: The present invention provides a process for preparing a supported chromium-based catalyst for the production of polyethylene comprising the steps of a) providing a silica-based support having a specific surface area of at least 250 m2/g and of less than 400 m2/g and comprising a chromium compound deposited thereon, the ratio of the specific surface area of the support to chromium content being at least 50000 m2/g Cr; b) dehydrating the product of step a); and c) titanating the product of step b) in an atmosphere of dry and inert gas containing at least one vaporised titanium compound of the general formula selected from RnTi(OR?)m and (RO)nTi(OR?)m, wherein R and R? are the same or different hydrocarbyl groups containing from 1 to 12 carbon atoms, and wherein n is 0 to 3, m is 1 to 4 and m+n equals 4, to form a titanated chromium-based catalyst having a ratio of specific surface area of the support to titanium content of the titanated catalyst ranging from 5000 to 20000 m2/g Ti.

Abstract: A process of producing polyethylene, the process comprising copolymerizing ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms in the presence of a chromium-based catalyst in a main polymerization reactor and, in a gas-phase preliminary reactor upstream of the main polymerization reactor, chemically treating the chromium-based catalyst with at least one treatment agent prior to introduction of the catalyst into the main polymerization reactor and releasing from the preliminary reactor waste gases produced during the chemical treatment.

Abstract: The present invention discloses the use of a supercritical fluid to improve the homogeneity of heterogeneous bi- or multi-modal resins resulting from a physical or a chemical blend of two or more fractions of the same type of polymer resin, said fractions having different molecular weights or of two or more polymer resins having different chemical compositions, or both. It also discloses the use of a supercritical fluid to improve the dispersion of additives or fillers into a polymer resin. It further discloses the process for preparing the homogeneous resin.

Abstract: The present invention concerns a catalyst for the production of high density polyethylene, by homopolymerising ethylene or copolymerising ethylene and an alpha-olefinic comonomer comprising 3 to 10 carbon atoms, prepared by the steps of: a) selecting a silica support with a specific surface area larger than 300 m2/g; b) treating the silica support with a titanium compound, in order to introduce titanium into the support, or with an aluminium compound, in order to introduce aluminium into the support; c) either treating the titanated silica support with an aluminum compound, in order to introduce aluminum into the titanated silica support, or treating the aluminated silica support with a titanium compound, in order to introduce titanium into the aluminated silica support; d) depositing a chromium compound on the titanated and aluminated silica support to form a catalyst; e) activating the catalyst of step d) under air in a fluidised bed at a temperature of from 600 to 800° C.

Abstract: The present invention concerns a catalyst for the production of high density polyethylene, by homopolymerising ethylene or copolymerising ethylene and an alpha-olefinic comonomer comprising 3 to 10 carbon atoms, prepared by the steps of: a) selecting a silica support with a specific surface area larger than 300 m2/g; b) treating the silica support with a titanium compound, in order to introduce titanium into the support, or with an aluminium compound, in order to introduce aluminium into the support; c) either treating the titanated silica support with an aluminum compound, in order to introduce aluminum into the titanated silica support, or treating the aluminated silica support with a titanium compound, in order to introduce titanium into the aluminated silica support; d) depositing a chromium compound on the titanated and aluminated silica support to form a catalyst; e) activating the catalyst of step d) under air in a fluidised bed at a temperature of from 600 to 800° C.

Abstract: A process for producing polypropylene having increased melt strength, the process comprising irradiating polypropylene which has been polymerised using a Ziegler-Natta catalyst with an electron beam having an energy of at least 5 MeV and a radiation dose of at least 10 kGray and mechanically processing the irradiated polypropylene to form long chain branches on the polypropylene molecules, whereby the polypropylene has a melt flow index (MFI) of at least 25 dg/min.

Abstract: The present invention discloses the use of a supercritical fluid to improve the homogeneity of heterogeneous bi- or multi-modal resins resulting from a physical or a chemical blend of two or more fractions of the same type of polymer resin, said fractions having different molecular weights or of two or more polymer resins having different chemical compositions, or both. It also discloses the use of a supercritical fluid to improve the dispersion of additives or fillers into a polymer resin. It further discloses the process for preparing the homogeneous resin.

Abstract: A process for producing polypropylene having increased melt strength, the process comprising (i) homopolymerising polypropylene or copolymerising propylene with one or more comonomers selected from ethylene and C4 to C101-olefins to produce a polypropylene homopolymer or copolymer respectively having a double bond concentration of at least 0.1 per 10,000 carbon atoms, (11) irradiating the polypropylene with an electron beam having an energy of at least 5 MeV and at radiation dose of at least 5 kGray, and (iii) melting and mechanically processing the melt of polypropylene to form long chain branches on the polypropylene molecules.

Abstract: A process for producing polypropylene having increased melt strength, the process comprising irradiating polypropylene which has been polymerised using a Ziegler-Natta catalyst with an electron beam having an energy of at least 5 MeV and a radiation dose of at least 10 kGray and mechanically processing the irradiated polypropylene to form long chain branches on the polypropylene molecules, whereby the polypropylene has a melt flow index (MFI) of at least 25 dg/min.

Abstract: A process of producing polyethylene, the process comprising copolymerizing ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms in the presence of a chromium-based catalyst in a main polymerization reactor and, in a gas-phase preliminary reactor upstream of the main polymerization reactor, chemically treating the chromium-based catalyst with at least one treatment agent prior to introduction of the catalyst into the main polymerization reactor and releasing from the preliminary reactor waste gases produced during the chemical treatment.

Abstract: A process of producing polyethylene, the process comprising copolymerizing ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms in the presence of a chromium-based catalyst in a main polymerization reactor and, in a gas-phase preliminary reactor upstream of the main polymerization reactor, chemically treating the chromium-based catalyst with at least one treatment agent prior to introduction of the catalyst into the main polymerization reactor and releasing from the preliminary reactor waste gases produced during the chemical treatment.