Abstract: A process for the preparation of ethylene polymers comprising polymerizing ethylene, optionally with one or more ?-olefin comonomers, in the presence of: (i) a solid catalyst component comprising titanium, magnesium, halogen and optionally an internal electron-donor compound, (ii) an aluminum alkyl compound, and (iii) an antistatic compound selected among the hydroxyesters with at least two free hydroxyl groups, wherein the weight ratio of aluminum alkyl compound to solid catalyst component is higher than 0.80 and the weight ratio of antistatic compound to aluminum alkyl compound is higher than 0.10.

Abstract: A process for preparing a polyolefin, including polymerizing olefins in the presence of an antistatic agent made from or containing an alkylene oxide derived polymer made from or containing in average from about 10 to about 200 repeating units —(CH2—CHR—O)— with R being hydrogen or an alkyl group having from 1 to 6 carbon atoms, wherein the alkylene oxide derived polymer is a random copolymer of ethylene oxide and other alkylene oxides and a ratio of n:m is in the range of from 6:1 to 1:1, wherein (n) is the average number of repeating units —(CH2—CH2—O)— derived from ethylene oxide and (m) is the average number of repeating units —(CH2—CHR?—O)— derived from the other alkylene oxides with R? being an alkyl group having from 1 to 6 carbon atoms, and the end groups of the alkylene oxide derived polymer are —OH groups.

Abstract: A process for preparing a polyolefin, including polymerizing olefins in the presence of an antistatic agent made from or containing an alkylene oxide derived polymer made from or containing in average from about 10 to about 200 repeating units —(CH2—CHR—O)— with R being hydrogen or an alkyl group having from 1 to 6 carbon atoms, wherein the alkylene oxide derived polymer is a random copolymer of ethylene oxide and other alkylene oxides and a ratio of n:m is in the range of from 6:1 to 1:1, wherein (n) is the average number of repeating units —(CH2—CH2—O)— derived from ethylene oxide and (m) is the average number of repeating units —(CH2—CHR?—O)— derived from the other alkylene oxides with R? being an alkyl group having from 1 to 6 carbon atoms, and the end groups of the alkylene oxide derived polymer are —OH groups.

Abstract: A process for the gas-phase polymerization of ethylene or a mixture of ethylene and one or more 1 olefins in the presence of a polymerization catalyst system comprising the steps a) feeding a solid catalyst component, which was obtained by contacting at least a magnesium compound and a titanium compound, to a continuously operated apparatus and contacting the solid catalyst component with an aluminum alkyl compound at a temperature of from 0° C. to 70° C. in a way that the mean residence time of the solid catalyst component in contact with the aluminum alkyl compound is from 5 to 300 minutes; b) transferring the catalyst component formed in step a) into another continuously operated apparatus and prepolymerizing it with ethylene or a mixture of ethylene and one or more 1 olefins in suspension at a temperature of from 10° C. to 80° forming polymer in an amount of from 0.

Abstract: The present disclosure provides a gas-phase polymerization process for preparing polyethylene, wherein halogenated alcohols in combination with a Ti based catalyst component and aluminum alkyls as co-catalyst suppress ethane formation or increase polymerization activity.

Abstract: The present technology relates to a method of introducing a supported antistatic compound that does not comprise a transition-metal-based catalyst component for use in an olefin polymerization reactor. In some embodiments, the methods disclosed herein avoid the formation of polymer agglomerates in the reactor and minimize potentially negative effects on catalyst yield.

Abstract: The present technology relates to a method of introducing a supported antistatic compound that does not comprise a transition-metal-based catalyst component for use in an olefin polymerization reactor. In some embodiments, the methods disclosed herein avoid the formation of polymer agglomerates in the reactor and minimize potentially negative effects on catalyst yield.

Abstract: Process for treating polyolefin particles obtained by gas-phase polymerization of one or more olefins in the presence of a polymerization catalyst system and a C3-C5 alkane as polymerization diluent in a gas-phase polymerization reactor, the process comprising the steps of a) discharging the polyolefin particles continuously or discontinuously from the gas-phase polymerization reactor and transferring the particles to a first degassing vessel; b) contacting therein the polyolefin particles with a gaseous stream comprising at least 85 mol-% of C3-C5 alkane while the polyolefin particles have an average residence time in the first degassing vessel of from 5 minutes to 5 hours; c) transferring the polyolefin particles to a second degassing vessel; d) contacting therein the polyolefin particles with a stream comprising nitrogen and steam while the polyolefin particles have an average residence time in the second degassing vessel of from 5 minutes to 2 hours, wherein the contacting is carried out at conditions un

Abstract: The present technology relates to a method of introducing a supported antistatic compound that does not comprise a transition-metal-based catalyst component for use in an olefin polymerization reactor. In some embodiments, the methods disclosed herein avoid the formation of polymer agglomerates in the reactor and minimize potentially negative effects on catalyst yield.

Abstract: A process for the gas-phase polymerization of ethylene or a mixture of ethylene and one or more 1 olefins in the presence of a polymerization catalyst system comprising the steps a) feeding a solid catalyst component, which was obtained by contacting at least a magnesium compound and a titanium compound, to a continuously operated apparatus and contacting the solid catalyst component with an aluminum alkyl compound at a temperature of from 0° C. to 70° C. in a way that the mean residence time of the solid catalyst component in contact with the aluminum alkyl compound is from 5 to 300 minutes; b) transferring the catalyst component formed in step a) into another continuously operated apparatus and prepolymerizing it with ethylene or a mixture of ethylene and one or more 1 olefins in suspension at a temperature of from 10° C. to 80° forming polymer in an amount of from 0.

Abstract: A process for the preparation of ethylene polymers comprising polymerizing ethylene, optionally with one or more ?-olefin comonomers, in the presence of: (i) a solid catalyst component comprising titanium, magnesium, halogen and optionally an internal electron-donor compound, (ii) an aluminum alkyl compound, and (iii) an antistatic compound selected among the hydroxyesters with at least two free hydroxyl groups, wherein the weight ratio of aluminum alkyl compound to solid catalyst component is higher than 0.80 and the weight ratio of antistatic compound to aluminum alkyl compound is higher than 0.10.

Abstract: Process for treating polyolefin particles obtained by gas-phase polymerization of one or more olefins in the presence of a polymerization catalyst system and a C3-C5 alkane as polymerization diluent in a gas-phase polymerization reactor, the process comprising the steps of a) discharging the polyolefin particles continuously or discontinuously from the gas-phase polymerization reactor and transferring the particles to a first degassing vessel; b) contacting therein the polyolefin particles with a gaseous stream comprising at least 85 mol-% of C3-C5 alkane while the polyolefin particles have an average residence time in the first degassing vessel of from 5 minutes to 5 hours; c) transferring the polyolefin particles to a second degassing vessel; d) contacting therein the polyolefin particles with a stream comprising nitrogen and steam while the polyolefin particles have an average residence time in the second degassing vessel of from 5 minutes to 2 hours, wherein the contacting is carried out at conditions un

Abstract: Process for preparing a polyolefin polymer comprising the steps of a) forming a particulate polyolefin polymer by polymerizing one or more olefins in the presence of a polymerization catalyst system in a polymerization reactor; b) discharging the formed polyolefin particles from the polymerization reactor; c) degassing the polyolefin particles by a process comprising at least a final step of contacting the polyolefin particles with a nitrogen stream in a degassing vessel; and d) transferring the polyolefin particles from the vessel, in which the contacting of the polyolefin particles with the nitrogen stream is carried out, to a melt mixing device, in which the polyolefin particles are melted, mixed and thereafter pelletized, without passing the particles through a buffering device, wherein the degassing vessel is only partly filled with polyolefin particles and the empty volume within the degassing vessel is sufficient to take up additional polyolefin particles for at least 3 hours if the transfer of pol

Abstract: Process for transferring polyolefin particles from a first gas-phase polymerization reactor to a second gas-phase polymerization reactor in a multistage polymerization of olefins carried out in at least two serially connected gas-phase polymerization reactors, wherein the first gas-phase reactor is a fluidized-bed reactor comprising a gas distribution grid and a settling pipe, which is integrated with its upper opening into the distribution grid and contains a bed of polyolefin particles which moves from top to bottom of the settling pipe, the process comprising the steps of introducing a fluid into the settling pipe in an amount that an upward stream of the fluid is induced in the bed of polyolefin particles above the fluid introduction point; withdrawing polyolefin particles from the lower end of the settling pipe; and transferring the withdrawn polyolefin particles into the second gas-phase polymerization reactor, process for polymerizing olefins comprising such a process for transferring polyolefin p

Abstract: Catalyst component comprising Mg, Ti, and halogen atoms, and is characterized in that (a) the Ti atoms are present in an amount higher than 4% based on the total weight of the said catalyst component, (b) the amount of Mg and Ti atoms is such that the Mg/Ti molar ratio is higher than 2 and (c) by a X-ray diffraction spectrum, in which, in the range of 2? diffraction angles between 47° and 52°, at least two diffraction lines are present at diffraction angles 2? of 48.3±0.2°, and 50.0±0.2°, the most intense diffraction lines being the one at 2? of 50.0±0.2°, the intensity of the other diffraction line being equal to or lower than the intensity of the most intense diffraction line.

Abstract: Process for transferring polyolefin particles from a first gas-phase polymerization reactor to a second gas-phase polymerization reactor in a multistage polymerization of olefins carried out in at least two serially connected gas-phase polymerization reactors, wherein the first gas-phase reactor is a fluidized-bed reactor comprising a gas distribution grid and a settling pipe, which is integrated with its upper opening into the distribution grid and contains a bed of polyolefin particles which moves from top to bottom of the settling pipe, the process comprising the steps of introducing a fluid into the settling pipe in an amount that an upward stream of the fluid is induced in the bed of polyolefin particles above the fluid introduction point; withdrawing polyolefin particles from the lower end of the settling pipe; and transferring the withdrawn polyolefin particles into the second gas-phase polymerization reactor, process for polymerizing olefins comprising such a process for transferring polyolefin partic

Abstract: A method for feeding an antistatic compound to a polymerization reactor, the method comprising the steps of: a) dispersing, under mixing conditions, a catalyst powder and an antistatic compound in a liquid medium, so as to form a suspension of the catalyst powder and of the antistatic compound in the liquid medium; b) transferring the obtained suspension to a polymerization reactor.

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 feeding an antistatic compound to a polymerization reactor, the method comprising the steps of: a) dispersing, under mixing conditions, a catalyst powder and an antistatic compound in a liquid medium, so as to form a suspension of the catalyst powder and of the antistatic compound in the liquid medium; b) transferring the obtained suspension to a polymerization reactor.

Abstract: Extruded articles, particularly films, comprising an ethylene polymer obtained by a polymerization process carried out in the presence the products obtained by contacting the following components: (a) a solid catalyst component comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and optionally one or more internal electron donor compounds, (b) an aluminum hydrocarbyl compound, (c) optionally an external electron donor compound, and (d) a polyalcohol partially esterified with carboxylic acids with alkyl groups having at least 10 carbon atoms.