Abstract: The present invention concerns heterophasic propylene copolymers, comprising a propylene homopolymer (PPH) and an ethylene-propylene rubber (EPR), having a broad molecular weight distribution and a well-defined total ethylene content and a specific ratio of the intrinsic viscosities of the ethylene-propylene rubber (EPR) and the propylene homopolymer (PPH), ?EPR/?PPH. The invention further concerns the process to produce such heterophasic propylene copolymers. The heterophasic propylene copolymers of the present invention are particularly suited for corrugated sheet and cast film applications.

Abstract: Copolymers of ethylene and ?-olefins are provided having (a) a density (D) in the range 0.900-0.940 g/cm3, (b) a melt index MI2 (2.16 kg, 190° C.) in the range of 0.01-50 g/10 min, (c) a melt index MI2 (2.16 kg, 190° C.) and Dow Rheology Index (DRI) satisfying the equation [DRI/MI2]>2.65, and (d) a Dart Drop Impact (DDI) in g of a blown film having a thickness of 25 ?m produced from the copolymer satisfying the equation DDI?1900×{1?Exp[?750(D?0.908)2]}×{Exp[(0.919?D)/0.0045]}. The copolymers may suitably be prepared by use of metallocene catalysis and are preferably prepared in multistage processes earned out in loop reactors in the slurry phase. The copolymers exhibit long chain branching as defined by Dow Rheology Index (DRI) and exhibit unexpected improvements in mechanical properties, in particular dart drop impact, when extruded into blown films.

Abstract: Process for the preparation of a multimodal polyolefin polymer at temperatures of from 40 to 150° C. and pressures of from 0.

Abstract: A propylene polymerization reaction apparatus and a production method of a propylene-based polymer are capable of producing a continuous multi-stage polymer in low cost, high productivity and stably, and significantly reducing generation amount of an off-specification product accompanying change of polymerization condition, in multi-stage continuous vapor phase polymerization method of a propylene-based polymer using a catalyst for olefin polymerization. A reaction apparatus for producing a propylene-based polymer by a multi-stage continuous vapor phase polymerization method is used. One or more reactor of a horizontal-type reactor having inside a stirring machine which rotates around a horizontal axis, and a continuous stirred tank reactor to be connected to the horizontal-type reactor are provided, and a production method of a propylene-based polymer using the same.

Abstract: A high pressure polymerization process to form an ethylene-based polymer comprises the steps of: A. Injecting a first feed comprising ethylene and optionally a chain transfer agent system (CTA system) into a first autoclave reactor zone operating at polymerization conditions to produce a first zone reaction product, the CTA system of the first reactor zone having a transfer activity Z1; and B. (1) Transferring at least part of the first zone reaction product to a second reactor zone selected from a second autoclave reactor zone or a tubular reactor zone and operating at polymerization conditions, and, optionally, (2) freshly injecting a second feed into the second reactor zone to produce a second zone reaction product, with the proviso that the second reactor zone contains a CTA system having a transfer activity Z2; and with the proviso that the ratio of Z1/Z2 is less than 1.

Abstract: According to one aspect, the present invention relates to a low-density polyethylene having a melt index MFR2 of 2.5 to 10.0 g/10 min, a density of 910 to 935 kg/m3, and a dynamic viscosity ?0.05 at a shear rate of 0.05 rad/s and a dynamic viscosity ?300 at a shear rate of 300 rad/s which satisfy the following relationship: ?300?108 Pa*s+0.0253*?0.05. According to a second aspect, the present invention relates to a low-density polyethylene having a melt index MFR2 of 2.5 to 10.0 g/10 min, a density of 910 to 935 kg/m3, and a phase shift ?0.5 at a frequency of 0.5 rad/s and a phase shift ?300 at a frequency of 300 rad/s, which satisfy the following relationship: tan ?300?0.45+0.164*tan ?0.5.

Abstract: The invention relates to a reactor system for the catalytic polymerization of olefin monomer and optionally comonomer(s), having one or more inlets for olefin monomer, catalyst, optionally for comonomer, chain growth controllers or chain transfer agents, and/or inert gas, an outlet for gas and an outlet for polymerized particles. The reactor system has at least one fluidized bed unit and at least one moving bed unit, wherein the fluidized bed unit has means for maintaining a fluidized bed in the fluidized bed unit and wherein the moving bed unit is provided with an inlet and an outlet which are directly connected to the fluidized bed unit, wherein the outlet of the moving bed unit is provided with means for pneumatically displacing polymer particles from the moving bed unit into the fluidized bed unit.

Abstract: An olefin polymerization reactor is provided with a first cylinder extending vertically; a first tapered cylindrical member placed in the first cylinder, having the inner diameter decreasing progressively downward, and having a gas inlet orifice at a bottom end thereof; a first liquid supplying part supplying a liquid so that the liquid may come into contact with an outer surface of the first tapered cylindrical member; and a gas supplying part supplying an olefin-containing gas through the gas inlet orifice into a first reaction region surrounded by an inner surface of the first tapered cylindrical member and an inner surface of the first cylinder above the first tapered cylindrical member, to form a spouted bed in the first reaction region.

Abstract: A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.

Abstract: The present invention relates to superabsorbent polymer comprising the comprising the free radical polymerization product of an aqueous monomer mixture containing at least one ?,?-ethylenically unsaturated monomer; at least one monomer having at least two ?,?-ethylenically unsaturated groups; a crosslinking agent having at least two polymerizable double bonds; iron ions in an amount of from about 0.1 to about 3 wppm based on the total weight of the aqueous monomer mixture; and at least one chelating agent in an amount to provide a molar ratio of chelating agent to iron ion of from about 0.8 to about 4.0.

Abstract: The present invention relates to a method for the continuous production of high-molecular polyesters by esterification of dicarboxylic acids and/or transesterification of dicarboxylic acid esters with diols and/or mixtures thereof in the presence of catalysts with formation of a prepolymer in a tower reactor and polycondensation thereof to form a high-molecular polyester in a polycondensation reactor, a prepolymer with >40 to 70 repeat units (DP) being produced in the tower reactor and this prepolymer being polycondensed in only one further reactor to form a polyester with >150 to 205 DP.

Abstract: The present invention provides a multiple loop reactor suitable for polymerizing olefins comprising at least two interconnected loop reactors, whereby said connection essentially consists of one or more transfer lines suitable for transferring polymer slurry from a reactor to another reactor and whereby said transfer line extends substantially horizontally. The invention further relates to a process for producing olefin polymers in a multiple loop reactor according to the invention. The invention also relates to the use of a transfer line for transferring polymer slurry from a reactor to another reactor in a multiple loop reactor comprising at least two interconnected loop reactors, whereby said transfer line extends substantially horizontally.

Abstract: A process for polymerizing olefins, comprising the steps of: (a) contacting in a dense-fluid-homogeneous-polymerization system (“PS”), >30 wt % C3+ olefins with: catalyst, activator, 0-50 mol % comonomer, and 0-40 wt % diluent/solvent, at a temperature > PS Tc and a pressure no lower than 1 MPa below the PS cloud point pressure and <200 MPa; (b) forming a reactor effluent comprising polymer-monomer mixture; (c) optionally heating the mixture (b); (d) collecting the mixture (b) in a separation vessel; (e) reducing the pressure to form a two-phase mixture where the pressure in the reactor is 7-100 MPa higher than the pressure in the separation vessel and the temperature in the separation vessel is > the polymer or above 80° C., whichever is higher; (f) separating the monomer-rich phase from the polymer-rich phase; (g) recycling the separated monomer-rich phase and recovering polymer from the polymer-rich phase.

Abstract: The present invention deals with a process of producing a polymer of at least one olefin in two consecutive reactors in gas phase in the presence of an olefin polymerisation catalyst where an olefin is polymerised in a first polymerization reactor in the presence of an olefin polymerisation catalyst and a first reaction gas mixture to form a fluidized bed comprising an olefin polymer and said first reaction gas mixture. The first reaction gas mixture together with the olefin polymer is continuously or intermittently withdrawn from the first polymerisation reactor and directed into a separation vessel so that a bed of polymer is formed in said separation vessel. A portion of said first reaction gas mixture is withdrawn from said separation vessel and returned into the first polymerization reactor to a point where the pressure is lower than in the separation vessel.

Abstract: A process for the gas-phase polymerization of one or more alpha-olefins in the presence of a polymerization catalyst, the process comprising: at least a polymerization step wherein the polymer particles flow downward in densified form under the action of gravity so as to form a densified polymer bed; metering an anti-fouling agent in said polymerization step by means of at least N feeding lines placed at different heights of said densified polymer bed, N being the integer number satisfying the equation N?(1+0.08·H), where H is the height (expressed in meters) of the polymer bed.

Abstract: A polymer comprises units derived from ethylene and polyalkylene, the polymer having at least 0.15 units of amyl groups per 1000 carbon atoms as determined by 13C Nuclear Magnetic Resonance (NMR).

Abstract: Heterophasic polypropylene composition comprising:—a polypropylene matrix (M) and—an elastomeric copolymer (E) being dispersed in the matrix (M), wherein the elastomeric copolymer (E) comprises units derived from—propylene and—ethylene and/or C4 to C20 ?-olefin, and wherein further,—the intrinsic viscosity of the xylene cold soluble fraction (XCS) of the heterophasic polypropylene composition is above 2.1 dl/g measured according to ISO 1628-1 (at 135° C. in decaline) and/or—Mz/Mw of the xylene cold soluble fraction (XCS) of the heterophasic polypropylene composition is more than 2.6, preferably 2.7, wherein the Mz is the z-average molecular weight measured according to ISO 16014-4:2003 and Mw is the weight average molecular weight measured according to ISO 16014-4:2003.

Abstract: Process for producing a multimodal polyethylene in at least two reactors connected in series, in which 20-80 wt % of a first polymer is made in suspension in a first reactor and 80-20 wt % of a second polymer is made in suspension in a second reactor in the presence of the first polymer, and a stream or slurry containing the resulting polymer is withdrawn from the second reactor and transferred to a flash tank operating at a pressure and temperature such that at least 50 mol % of the liquid component of the slurry, or the non-polymer component of the stream entering the flash tank, is withdrawn from the flash tank as a vapour, wherein the concentration in the stream or slurry entering the flash tank of components having a molecular weight below 50 g/mol, Clights (mol %), satisfies the equation Clights<7+0.07(40?Tc)+4.4(Pc?0.8)?7(CH2/CEt) where Tc and Pc are respectively the temperature (in ° C.

Abstract: Process for producing a multimodal polyethylene in at least two loop reactors connected in series. In the process 20-80 wt % of a high molecular weight (HMW) polymer is made in suspension in a first reactor and 20-80 wt % of a low molecular weight (LMW) polymer is made in suspension in a second reactor, one polymer being made in the presence of the other in either order. The ratio of the average activity in the LMW reactor to the average activity in the HMW reactor is from 0.25 and 1.5, where average activity in each reactor is defined as the rate of polyethylene produced in the reactor (kgPE/hr)/[ethylene concentration in the reactor (mol %)×residence time in the reactor (hours)×feed rate of catalyst into the reactor (g/hr)], residence time being defined as the mass of the polymer in the reactor (kg)/the output rate of polymer from the reactor (kg/hr), and the volumes of the two reactors differ by less than 10%.

Abstract: The present invention relates to a process of producing an ethylene polymer composition in multiple stages of which the first stage is a slurry polymerization stage, in the presence of a catalyst system comprising a) a solid catalyst precursor comprising a transition metal selected from titanium and vanadium; magnesium, a halide, optionally an electron donor, and a solid particulate material comprising an inorganic oxide, wherein the median particle diameter of the solid catalyst precursor based upon the total volume of solid catalyst precursor, D50, is from 1 to 13 micrometers; and b) an organoaluminium compound.

Abstract: Catalysts are activated in a dual reactor solution process by adding substoichiometric and superstoichiometric amounts of an ionic activator to an organometallic polymerization catalyst in a first and second reactor respectively. The new activation method allows one to alter process conditions in a favorably way with minimum impact to process economics. The new activation method also provides polymers which give films having improved optical properties.

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.

Abstract: The polymer degassing apparatus includes a barrel-shaped horizontal container 41 having a supply port 42 for supplying a reactant, a discharge port 43 for discharging a reactant, a stirring means 45 for stirring a reactant, and a degassing means for drawing a gas via a degassing port 44 of the horizontal container. The supply port is positioned below the molten liquid level of the reactant. A recovery container 37 that is connected to the degassing port for recovering a volatile substance in the gas and a vacuum pump 36 are provided. The stirring means includes a plurality of stirring rods 46 oriented along the same direction as the axis in the horizontal container and coupling members 47 for coupling the stirring rods along the same direction as the axis, provided that the coupling members are placed at a distance from the virtual rotation center of the stirring means.

Abstract: The present invention relates to process for the preparation of a superabsorbent polymer comprising the steps of a) subjecting an aqueous monomer mixture containing at least one ?,?-ethylenically unsaturated monomer; at least one monomer bearing at least two ?,?-ethylenically unsaturated groups; iron ions in an amount of 0.1 to 3 wppm based on the total weight of the aqueous monomer mixture; and at least one chelating agent in an amount to provide a mol ratio of chelating agent to iron ion of 0.8 to 4.0 to free radical polymerization in an reactor to obtain a super-absorbent polymer; and b) recovering the superabsorbent polymer, whereby if the process is continuous and is run in an agitated reactor the upper limit of the mol ratio of chelating agent to iron ion is 4.0 for a throughput of total reaction mixture through the reactor of at most 1.3 kg/h per liter reactor volume.

Abstract: A polyester production system employing a vertically elongated esterification reactor. The esterification reactor of the present invention is an improvement over conventional CSTR esterification reactors because, for example, in one embodiment, the reactor requires little or no mechanical agitation. Further, in one embodiment, the positioning of the inlets and outlets of the reactor provides improved operational performance and flexibility over CSTRs of the prior art.

Abstract: A process for the polymerization of olefins is disclosed. The process may include: feeding a catalyst, a liquid diluent, and an olefin to a polymerization vessel having, from a polymerization vessel bottom to a polymerization vessel top, a vapor introduction zone, a three-phase reaction zone and a vapor disengagement zone; contacting the catalyst and olefin under conditions of temperature and pressure in the presence of the liquid diluent as a continuous phase in the three-phase reaction zone to form a solid phase polyolefin; withdrawing a gas phase composition from an outlet in fluid communication with the vapor disengagement zone; circulating the gas phase composition through a gas circulation loop to an inlet in fluid communication with the vapor distribution zone at a rate sufficient to agitate the solid and liquid phases within the three-phase reaction zone; and withdrawing a reaction mixture comprising polyolefin and diluents from the three-phase reaction zone.

Abstract: This invention discloses caps and closures produced by injection moulding with a bimodal high density polyethylene (HDPE) resin comprising a low molecular weight, high density polyethylene fraction substantially free of comonomer and a high molecular weight, low density polyethylene fraction, having a molecular weight distribution of at least 3.5, preferably greater than 4.0, prepared in two reactors connected in series in the presence of a metallocene-containing catalyst system, wherein the metallocene comprises a bisindenyl or a bis-tetrahydrogenated-indenyl component.

Abstract: The present disclosure provides a polymerization process for the production of a high melt flow propylene impact copolymer. The process includes contacting an active propylene-based polymer having a melt flow rate greater than about 100 g/10 min with one or more olefins in a polymerization reactor to form the propylene impact copolymer with a melt flow rate greater than about 60 g/10 min. The production of the high melt flow propylene impact copolymer may occur in one or more polymerization reactors, utilizing standard hydrogen concentration, and no visbreaking.

Abstract: Process for producing a multimodal polyethylene in at least two reactors connected in series, in which 20-80 wt % of a high molecular weight (HMW) polymer is made in suspension in a first reactor and 20-80 wt % of a low molecular weight (LMW) polymer is made in suspension in a second reactor in the presence of the HMW polymer, wherein the solids concentration in the second LMW reactor, defined as the mass of polymer divided by the total mass of slurry, is at least 35 wt %, most preferably between 45 wt % and 60 wt %, and/or the ratio of solids concentration in the first reactor to that in the second reactor is maintained at less than 1.0, preferably between 0.6 and 0.8, and further wherein the volume of the second reactor is at least 10%, preferably at least 30% and more preferably at least 50% greater than the volume of the first reactor.

Abstract: Polymerisation process in which polyethylene is produced in slurry in a polymerisation reactor in the presence of a Ziegler Natta catalyst and an activator, and a stream or slurry containing the polymer is withdrawn from the reactor and transferred to a flash tank operating at a pressure and temperature such that at least 50 mol % of the liquid or non-polymer component of the stream entering the flash tank or slurry is withdrawn from the flash tank as a vapour and at least 98 mol % of the vapour withdrawn from the flash tank is capable of being condensed at a temperature of between 15 and 50° C., without compression. A by-product suppressor, which reduces the amount of by-product formed per unit of polyethylene produced by at least 10%, compared with an identical polymerisation process where the by-product suppressor is not present, is used in the reactor. The molar ratio of the by-product suppressor added to the reactor to titanium added to the reactor is between 0.2 and 1.

Abstract: Process for producing a multimodal polyethylene in at least two reactors connected in series, in which 20-80 wt % of a high molecular weight (HMW) polymer is made in suspension in a first reactor and 20-80 wt % of a low molecular weight (LMW) polymer is made in suspension in a second reactor. The ratio of the average activity in the LMW reactor to the average activity in the HMW reactor is from 0.25 and 1.5, where average activity in each reactor is defined as the rate of polyethylene produced in the reactor (kgPE/hr)/[ethylene concentration in the reactor (mol %)×residence time in the reactor (hours)×feed rate of catalyst into the reactor (g/hr)], residence time being defined as the mass of the polymer in the reactor (kg)/the output rate of polymer from the reactor (kg/hr). The volume of the second reactor is at least 10% greater than the volume of the first reactor, and the ratio of length to diameter of the first reactor, L/D(1), is greater than that of the second reactor, L/D(2).

Abstract: Bimodal polyethylene resins having reduced long-chain branching and suitable for use in pipe resin applications as a result of their improved SCG and RCP resistance are provided. The improved resins of the invention are produced in a two-reactor cascade slurry polymerization process using a Ziegler-Natta catalyst system and wherein an alkoxysilane modifier is present in both reactors.

Abstract: Propylene polymers having specific values of total comonomer content and melting temperature, articles obtained therefrom, in particular extrusion blow molded articles, and gas-phase process for obtaining said propylene polymers.

Abstract: The present invention relates to an improvement for gas phase olefin polymerization process under two or more different flow regimes. The process involves adding a mixed electron donor system to a reactor having two or more different flow regimes, wherein the mixed electron donor system comprises at least one selectivity control agent and at least one activity limiting agent. The invention is particularly well suited for reactor systems which include a regime characterized by having a low-velocity or high-solid holdup, which have been reported to have operational problems such as particle agglomeration and formation of polymer “chunks”.

Abstract: Novel polyethylenes having defined molecular weight distribution and LCB structure are devised, for films or mouldings.

Abstract: An olefin polymerization reactor according to the present invention comprises: a vertically extending cylinder; a decreasing diameter portion on the cylinder, having an inside diameter that decreases progressively downward, and having a gas inlet orifice at a bottom end thereof; and a plurality of through holes passing through from an outside surface towards an inside surface of the decreasing diameter portion. Inside a reaction zone enclosed by an inside surface of the decreasing diameter portion and an inside surface above the decreasing diameter portion of the cylinder, a spouted-fluidized bed or a spouted bed is formed.

Abstract: An olefin polymerization process comprises gas-phase polymerization of at least one olefin monomer in more than one polymerization zones in one or more polymerization reactors using a high activity catalyst injected in the front end of the reactor to give solid polymer particles. According to the process of the invention, different hydrogen to olefin ratios are applied to the reactor leading to the production of very different molecular weights and therefore broadening the molecular weight distribution of the polymer produced.

Abstract: Process for the production of polypropylene random copolymers containing 2.5 to 5.0 wt % of ethylene as comonomer and having an MFR2 in accordance with ISO 1 133 (230° C., 2.16 kg load) of ?25 g/10 min to 100 g/10 min and a hexane-solubles content, determined according to FDA CFR 21 §177.

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 invention provides a process for preparing polymers based on vinyl ester, ethylene and optionally further comonomers in the form of aqueous polymer dispersions thereof or of water-redispersible polymer powders by means of free-radically initiated continuous emulsion polymerization and optionally drying of the resulting polymer dispersions, characterized in that the emulsion polymerization is carried out in a cascade comprising at least one upstream heat exchanger and at least two downstream pressurized stirred tank reactors connected in series, such that the conversion on leaving the heat exchanger is at least 10% of the overall polymerization conversion.

Abstract: Process for transferring a slurry stream containing polymer through a transfer line from a polymerisation reactor to a downstream vessel by, prior to entry into the downstream vessel, separating the slurry stream into two flows, the first flow being recycled upstream of the flow separation and the second flow being passed into the downstream vessel. The flow separation is located more than halfway along the transfer line between the reactor and the downstream vessel.

Abstract: A process for the polymerization of olefins carried out in a gas-phase reactor having interconnected polymerization zones, where the growing polymer particles flow upward through a first polymerization zone (riser) under fast fluidization or transport conditions, leave said riser and enter a second polymerization zone (downcomer) through which they flow downward under the action of gravity, leave said downcomer and are reintroduced into the riser, a gas recycle stream being withdrawn from said first polymerization zone, subjected to cooling below its dew point and then returned to said first polymerization zone, the process being characterized in that said gas recycle stream is cooled at a temperature Tc ranging from 0.05° C. to 3° C. below its dew point.

Abstract: The invention relates to a continuous process for preparing polyolefins having a bimodal or multimodal molar mass distribution in suspension in at least two reactors R1, R2.x, R3.y which are connected in series and in which different reaction conditions are set. In this process, the offgases A1, A2.x, A3.y, A4 and A5 leaving all the reactors connected in series are firstly collected, the collected offgases are then compressed in a compression stage 10, the compressed offgases are subsequently cooled and the cooled material is separated into a gaseous fraction and a liquid fraction. The separated fractions are then recirculated to the polymerization process at different points. The process of the invention allows the total conversion of the polymerization, based on monomer and comonomer used, to be increased to a surprising extent.

Abstract: A process for fluid phase in-line blending of polymers.

Abstract: Installation for the gas-phase polymerization of at least one olefinic monomer, comprising a horizontal stirred reactor (1) consisting of an undivided space, provided with a number of gas feeds (13a-13) in the bottom section of the reactor (1) and a number of liquid feeds (7a-7) in the top section of the reactor (1) and at least two gas outlets (9, 11) at the top of the reactor (1), the installation being provided with means (43, 45) to regulate the discharge capacities of the gas outlets.

Abstract: The present invention relates to a loop reactor suitable for olefin polymerization process comprising: a plurality of interconnected pipes defining a flow path for a polymer slurry, said slurry consisting essentially of an olefin reactant, a polymerization catalyst, liquid diluent and solid olefin polymer particles, means for introducing olefin reactant, polymerization catalyst and diluent into said reactor, a pump suitable for maintaining the polymer slurry in circulation in said reactor, and single settling leg connected to said loop reactor through (a) a take off line extending from said reactor to said settling leg and configured to remove said polymer slurry from said reactor, and (b) a return line extending from said settling leg to said reactor, characterized in that said take off line is radially connected to said single settling leg.

Abstract: A bimodal polyethylene having a high density ranging from about 0.955 to about 0.959 g/cc, an improved environmental stress cracking resistance (ESCR) of from about 400 to about 2500 hours, and an improved 0.4% flexural modulus of from about 180,000 to about 260,000 psi (1,200 MPa to about 1,800 MPa) may be formed using a Ziegler-Natta polymerization catalyst using two reactors in series. The bimodal polyethylene may have a high load melt index (HLMI) of from about 2 and about 30 dg/min and may be optionally made with a small amount of alpha-olefinic comonomer in the second reactor. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: Disclosed herein are various processes, including continuous fluidized-bed gas-phase polymerization processes for making a high strength, high density polyethylene copolymer, comprising (including): contacting monomers that include ethylene and optionally at least one non-ethylene monomer with fluidized catalyst particles in a gas phase in the presence of hydrogen gas at an ethylene partial pressure of 100 psi or more and a polymerization temperature of 120° C. or less to produce a polyethylene copolymer having a density of 0.945 g/cc or more and an ESCR Index of 1.0 or more wherein the catalyst particles are prepared at an activation temperature of 700° C. or less, and include silica, chromium, and titanium.

Abstract: A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The discharge system includes a fluidized bed pressure vessel, a settling vessel, a transfer vessel, discharge line, primary discharge valve, and primary exit valve. Also in included is a method to operate the discharge system. The method includes transferring a solid/gas mixture from a fluidized bed pressure vessel to a settling vessel, transferring the solids to a transfer vessel, and then emptying the transfer vessel.

Abstract: Embodiments of the invention provide a class of mesophase separated ethylene/?-olefin block interpolymers with controlled block sequences. The ethylene/?-olefin interpolymers are characterized by an average block index, ABI, which is greater than zero and up to about 1.0 and a molecular weight distribution, Mw/Mn, greater than about 1.4. Preferably, the block index is from about 0.2 to about 1. In addition or alternatively, the block ethylene/?-olefin interpolymer is characterized by having at least one fraction obtained by Temperature Rising Elution Fractionation (‘TREF’), wherein the fraction has a block index greater than about 0.3 and up to about 1.0 and the ethylene/?-olefin interpolymer has a molecular weight distribution, Mw/Mn, greater than about 1.4.