Basell Poliolefine Italia S.r.l.

Basell Polyolefine Gmbh

Basell Poliolefine Italia, S.p.a.

Montell Technology Company Bv

Himont Incorporated

Basell Technology Company B.v.

Equistar Chemicals, LP

Montell North America Inc.

Montech USA Inc.

Massimo Covezzi

Gabriele Mei

Pietro Baita

Gabriele Govoni

Roberto Rinaldi

Gerhardus Meier

Roberta Pica

Paolo Galli

Lorella Marturano

Gianni Collina

Ulf Schueller

Giuliano Cecchin

Anna Fait

Giuseppe Penzo

Antonio Mazzucco

Maria Di Diego

Daniele Bigiavi

Giampiero Morini

Shahram Mihan

Claudio Cavalieri

Marco Ciarafoni

Gianni Vitale

Enrico Balestra

Maria Silvia Tonti

Gerben Meier

Piero Gessi

Remo Anibaldi

Paola Massari

Tiziano Dall'Occo

Fabrizio Piemontesi

Dario Liguori

Tiziana Caputo

Harilaos Mavridis

Michele Grazzi

Fabiana Fantinel

Joachim T M Pater

Roberta Marzolla

Giulia Mei

Riccardo Rinaldi

Antonio Ciarrocchi

Maurizio Dorini

Claudio Cometto

Gianpiero Ferraro

Stefano Bertolini

Nicolò Arich De Finetti

Antonio De Lucia

Bodo Richter

Guiseppe Penzo

Nicolo' Arich De Finetti

Almerinda Di Benedetto

Jean News

Ricardo Rinaldi

Tiziano Dall'occo

Joachim T Pater

A process for preparing an ethylene polymer including the step of homopolymerizing ethylene or copolymerizing ethylene with one or more comonomers in a gas-phase polymerization reactor including a riser unit wherein growing polymer particles flow upwards under fluidization, fast fluidization or transport conditions and a downcomer wherein growing polymer particles flow downward in a densified form, wherein the hold-up of polymer particles in the downcomer is from 55 wt. % to 80 wt. % of the total hold-up of polymer particles in the gas-phase polymerization reactor.

Olefin polymerization process in a gas-phase reactor comprising a riser unit and a downcomer

A fluid is fed into a polymer bed of a fluidized bed gas phase polymerization reactor by introducing the fluid into the polymer bed through a distributor protruding into the fluidized bed zone of the reactor and terminating with a discharge end positioned so that the following equation is fulfilled:&#x3e;0.002wherein d is the distance of the distributor's discharge end from the wall of the reactor, and D is the diameter of the reactor in the fluidized bed zone.

Method for feeding a fluid to a gas phase polymerization reactor

A gas-phase process for the homopolymerization or copolymerization of propylene with other olefins, including carrying out the polymerization in the presence of a catalyst system made from or containing: (a) a solid catalyst component made from or containing Mg, Ti, halogen, an electron donor selected from 1.3-diethers and an olefin polymer in a specific amount; (b) an aluminum alkyl compound and (c) an external electron donor (ED) compound, wherein components (b) and (c) being employed in amounts such that the Al/(ED) molar ratio ranges from about 2 to about 200.

Gas-phase process for the polymerization of propylene

The present disclosure generally relates to ethylene alpha-olefin copolymers and methods of making ethylene alpha-olefin copolymers. The ethylene alpha-olefin copolymers may have a density of about 0.915 g/mL to about 0.918 g/mL, a rheological polydispersity index greater than 0.8, a melt index of about 0.4 dg/10 min to about 2.0 dg/10 min, and/or a CEF Tof 84&#xb0; C. or less. The ethylene alpha-olefin copolymers may be made by combining an ethylene monomer and one or more alpha-olefin monomers in the presence of a catalyst, such as a Ziegler-Natta catalyst.

Ethylene alpha-olefin copolymers and methods

A propylene polymer composition made from or containing:

Propylene based polymer composition

A gas-phase process for the homopolymerization or copolymerization of olefins carried out in the presence of a catalyst system formed by a contacting, in a liquid hydrocarbon and in the presence of hydrogen, (a) a solid catalyst component comprising Ti, Mg, and Cl, and optionally an internal electron donor compound, (b) an aluminum alkyl compound and optionally (c) an external donor compound.

Process for the polymerization of olefins

A process for starting a multizone circulating reactor containing no polyolefin particles, comprising the steps of conveying gas through the reactor and the gas recycle line, feeding a particulate material comprising a polymerization catalyst and optionally polyolefin into the reactor, controlling the gas flow in a vertical reactor zone equipped with a throttling valve at the bottom so that the upwards gas velocity in the bottom part of this reaction zone is lower than the terminal free-fall velocity of the particulate material fed into the reactor, and, after the weight of the particulate polyolefin in this reactor zone is higher than the drag force of the upward moving gas, controlling the circulation rate of the polymer particles within the multizone circulating reactor by adjusting the opening of the throttling valve and adjusting the flow rate of a dosing gas.

Process for start-up of a multizone circulating reactor

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.

Method for improving the operability of an olefin polymerization reactor

A process for the preparation of ethylene polymers comprising polymerizing ethylene, optionally with one or more &#x3b1;-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.

Process for the preparation of ethylene polymers

A two steps polymerization process for obtaining a polyolefin composition comprising:

Process for the obtainment of a polyolefin composition

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 ofintroducing 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; andtransferring the withdrawn polyolefin particles into the second gas-phase polymerization reactor,process for polymerizing olefins comprising such a process for transferring polyolefin particles, reactor suitable as first gas-phase polymerization reactor in the process for polymerizing olefins and process for discharging polyolefin particles from a fluidized-bed reactor.

Multistage process for the polymerization of olefins

A method for transitioning from a first to a second catalyst system for the olefin polymerization reaction in one reactor, wherein the first catalyst system is incompatible with the second catalyst system, is described. The method comprises the steps of a) discontinuing a first olefin polymerization reaction performed in the presence of the first catalyst system; and b) performing a second olefin polymerization reaction in the presence of the second catalyst system comprising catalyst components (A) and (B) producing, respectively, a first and a second polyolefin fraction, wherein the Mof the first polyolefin fraction is less than the Mof the second polyolefin fraction and the initial activity of catalyst component (A) exceeds the initial activity of catalyst component (B). Thanks to this method, there is no need to empty the reactor after the first olefin polymerization reaction, and the transitioning time needed to attain the desired quality of the polyolefin obtained in the second olefin polymerization reaction is sufficiently short to permit a quick and reliable change of production.

Method for transitioning between incompatible olefin polymerization catalyst systems

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:

Process for the (co)polymerization of ethylene

Process for the gas-phase polymerization of one or more alpha-olefins in the presence of a catalyst system, the process comprising:

Process for the gas-phase polymerization olefins

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Ferrara, Italy

Massimo Covezzi