Abstract: A reactor for carrying out a gas-phase olefin polymerization in the presence of a polymerization catalyst, made from or containing (i) a first polymerization zone adapted and arranged for growing polymer particles to flow upward under fast fluidization or transport conditions, (ii) a second polymerization zone adapted and arranged for the growing polymer particles to flow downward, and (iii) a set of bars for introducing feedstock or a barrier stream into the reactor, wherein each bar has (a) a hollow space along the length of the bar, (b) a particle deviating top, and (c) a multiplicity of openings arranged along the bottom half of the periphery of the bar.

Abstract: A propylene ethylene copolymer having: (i) an ethylene derived units content (C2) ranging from 2.0 wt % to 11.0 wt %, based upon the total weight of the copolymer; (ii)) a fraction soluble in xylene (Xs) at 25° C. (Xs) ranging from 7.1 wt % to 28.5 wt %, based upon the total weight of the copolymer; (iii) an intrinsic viscosity of the fraction soluble in xylene at 25° C. ranging from 3.2 dl/g to 5.6 dl/g; (iv) a melting point (Tm) higher than 140.0° C. and fulfilling the relation (I): Tm>155?1.4×C2??(I); and (v) a flexural modulus (TM) higher than 500 MPa and fulfilling the relation (II) TM>1900?285×C2+50×Xs??(II).

Abstract: Process for the preparation of heterophasic propylene copolymer compositions (RAHECO) made from or containing a random propylene copolymer (RACO) and an elastomeric propylene copolymer (BIPO), the process being carried out in a reactor having two interconnected polymerization zones, a riser and a downcomer, wherein growing polymer particles: (a) flow through the first polymerization zone, the riser, under fast fluidization conditions in the presence of propylene and of ethylene or an alpha-olefin having from 4 to 10 carbon atoms, thereby obtaining the random propylene copolymer (RACO); (b) leave the riser and enter the second polymerization zone, the downcomer, through which the growing polymer particles flow downward in a densified form in the presence of propylene and of ethylene or an alpha-olefin having from 4 to 10 carbon atoms, wherein the concentration of ethylene or of the alpha-olefin in the downcomer is higher than in the riser, thereby obtaining the elastomeric propylene copolymer (BIPO); and (c)

Abstract: A process for the polymerization of olefins in gas phase carried out in a reactor having two interconnected polymerization zones, a first zone (riser) and a second zone (downcomer), wherein growing polymer particles: a) flow through the riser under fast fluidization conditions established by feeding a mixture of gas and liquid; b) leave the riser and enter the downcomer, through which the growing polymer particles flow downward in a densified form; and c) leave the downcomer and are reintroduced into the riser, thereby establishing a circulation of polymer between the riser and the downcomer; the reactor is operated at a temperature between 0° C. and 5° C. above the dew point of the riser gas at the operating pressure, and in the riser, besides the growing polymer particles and gas flow, an amount of liquid is present.

Abstract: A manhole for a polymerization unit having a through-hole formed with a shoulder matching a corresponding shoulder of a plug of a closure member operatively inserted in the through-hole. The through-hole can be closed with a minimum clearance, such that polymer particles do not deposit in the gap between the wall of the unit and the plug of the closure member.

Abstract: A manhole for a polymerization unit having a through-hole formed with a shoulder matching a corresponding shoulder of a plug of a closure member operatively inserted in the through-hole. The through-hole can be closed with a minimum clearance, such that polymer particles do not deposit in the gap between the wall of the unit and the plug of the closure member.

Abstract: 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: d/D>0.002 wherein 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.

Abstract: A process for the polymerization of olefins in gas phase carried out in a reactor having two interconnected polymerization zones, a first zone (riser) and a second zone (downcomer), wherein growing polymer particles: a) flow through the riser under fast fluidization conditions established by feeding a mixture of gas and liquid; b) leave the riser and enter the downcomer, through which the growing polymer particles flow downward in a densified form; and c) leave the downcomer and are reintroduced into the riser, thereby establishing a circulation of polymer between the riser and the downcomer; the reactor is operated at a temperature between 0° C. and 5° C. above the dew point of the riser gas at the operating pressure, and in the riser, besides the growing polymer particles and gas flow, an amount of liquid is present.

Abstract: A process for the preparation of polyolefins carried out in the presence of an antistatic composition made from or containing: a) a compound of formula R—OH wherein R represents hydrogen or a linear or branched, saturated alkyl group having from 1 to 15 carbon atoms; and b) an oligomeric or polymeric organic compound having one or more terminal hydroxyl groups and a viscosity at 40° C. of at least about 20 mm2/sec (DIN 51562).

Abstract: A propylene ethylene copolymer having: (i) an ethylene derived units content (C2) ranging from 2.0 wt % to 11.0 wt %, based upon the total weight of the copolymer; (ii)) a fraction soluble in xylene (Xs) at 25° C. (Xs) ranging from 7.1 wt % to 28.5 wt %, based upon the total weight of the copolymer; (iii) an intrinsic viscosity of the fraction soluble in xylene at 25° C. ranging from 3.2 dl/g to 5.6 dl/g; (iv) a melting point (Tm) higher than 140.0° C. and fulfilling the relation (I): Tm>155?1.4×C2 ??(I); and (v) a flexural modulus (TM) higher than 500 MPa and fulfilling the relation (II) TM>1900?285×C2+50×Xs ??(II).

Abstract: Process for the preparation of heterophasic propylene copolymer compositions (RAHECO) made from or containing a random propylene copolymer (RACO) and an elastomeric propylene copolymer (BIPO), the process being carried out in a reactor having two interconnected polymerization zones, a riser and a downcomer, wherein growing polymer particles: (a) flow through the first polymerization zone, the riser, under fast fluidization conditions in the presence of propylene and of ethylene or an alpha-olefin having from 4 to 10 carbon atoms, thereby obtaining the random propylene copolymer (RACO); (b) leave the riser and enter the second polymerization zone, the downcomer, through which the growing polymer particles flow downward in a densified form in the presence of propylene and of ethylene or an alpha-olefin having from 4 to 10 carbon atoms, wherein the concentration of ethylene or of the alpha-olefin in the downcomer is higher than in the riser, thereby obtaining the elastomeric propylene copolymer (BIPO); and (c)

Abstract: 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.

Abstract: 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: d/D>0.002 wherein 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.

Abstract: A process for the preparation of polyolefins carried out in the presence of an antistatic composition made from or containing: a) a compound of formula R—OH wherein R represents hydrogen or a linear or branched, saturated alkyl group having from 1 to 15 carbon atoms; and b) an oligomeric or polymeric organic compound having one or more terminal hydroxyl groups and a viscosity at 40° C. of at least about 20 mm2/sec (DIN 51562).

Abstract: 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.

Abstract: A process and apparatus for producing olefin polymers are disclosed, comprising: a. polymerizing one or more olefins in the gas phase, in the presence of an olefin polymerization catalyst, whereby growing polymer particles flow along a cylindrically-shaped downward path in densified form under the action of gravity so as to form a densified bed of downward-flowing polymer particles b. allowing said polymer particles to flow through a restriction of the densified bed, such restriction being positioned in a restriction zone extending from the bed upward to a distance of 15% of the total height of the densified bed; and c. metering an antistatic agent through a feed line connected to the densified bed at a feed point being located in a feed zone extending from the top of the restriction upward, to a distance five times the diameter of the section of the densified bed above the restriction.

Abstract: A process and apparatus for producing olefin polymers are disclosed, comprising: a. polymerizing one or more olefins in the gas phase, in the presence of an olefin polymerization catalyst, whereby growing polymer particles flow along a cylindrically-shaped downward path in densified form under the action of gravity so as to form a densified bed of downward-flowing polymer particles b. allowing said polymer particles to flow through a restriction of the densified bed, such restriction being positioned in a restriction zone extending from the bed upward to a distance of 15% of the total height of the densified bed; and c. metering an antistatic agent through a feed line connected to the densified bed at a feed point being located in a feed zone extending from the top of the restriction upward, to a distance five times the diameter of the section of the densified bed above the restriction.

Abstract: A process for the gas-phase copolymerization of: (a) propylene, (b) at least one C4-C8 ?-olefin, and (c) optionally ethylene, the process being carried out in a reactor having two interconnected polymerization zones, wherein the growing polymer particles flow through the first of said polymerization zones (riser) under fast fluidization conditions, leave said riser and enter the second of said polymerization zones (downcomer) through which they flow downward in a densified form, leave said downcomer and are reintroduced into said riser, thus establishing a circulation of polymer between the riser and the downcomer, the gas mixture present in the riser being at least partially prevented from entering the downcomer by introducing into the upper part of said downcomer a liquid barrier having a composition different from the gaseous mixture present in the riser and comprising at least one C4-C8 ?-olefin in a total amount of from 0.1% to 35% by mol.

Abstract: A process for the gas-phase copolymerization of: (a) propylene, (b) at least one C4-C8 ?-olefin, and (c) optionally ethylene, the process being carried out in a reactor having two interconnected polymerization zones, wherein the growing polymer particles flow through the first of said polymerization zones (riser) under fast fluidization conditions, leave said riser and enter the second of said polymerization zones (downcomer) through which they flow downward in a densified form, leave said downcomer and are reintroduced into said riser, thus establishing a circulation of polymer between the riser and the downcomer, the gas mixture present in the riser being at least partially prevented from entering the downcomer by introducing into the upper part of said downcomer a liquid barrier having a composition different from the gaseous mixture present in the riser and comprising at least one C4-C8 ?-olefin in a total amount of from 0.1% to 35% by mol.

Abstract: A process for the gas-phase polymerization of ?-olefins carried out in two interconnected polymerization zones, wherein the growing polymer particles flow through the first of said polymerization zones (riser) under fast fluidization conditions, leave said riser and enter the second of said polymerization zones (downcomer) through which they flow downward in a densified form, the process being characterized in that: (a) the gas mixture present in the riser is totally or partially prevented from entering the downcomer by introducing into the upper part of said downcomer a liquid stream LB having a composition different from the gaseous mixture present in the riser; (b) the ratio R between the flow rate Fp of polymer circulated between said downcomer and said riser and the flow rate LB of said liquid being adjusted in a range from 10 to 50.