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POLYMERIZING IN TUBULAR OR LOOP REACTOR

Subclass of:

526 - Synthetic resins or natural rubbers -- part of the class 520 series

526000000 - SYNTHETIC RESINS (CLASS 520, SUBCLASS 1)

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DocumentTitleDate
20080275196POLYESTER PROCESS USING A PIPE REACTOR - The invention is directed to polyester processes that utilizes a pipe reactor in the esterification, polycondensation, or both esterification and polycondensation processes. Pipe reactor processes of the present invention have a multitude of advantages over prior art processes including improved heat transfer, volume control, agitation and disengagement functions.11-06-2008
20110178253HIGH PRESSURE LOW DENSITY POLYETHYLENE RESINS WITH IMPROVED OPTICAL PROPERTIES PRODUCED THROUGH USE OF HIGHLY ACTIVE CHAIN TRANSFER AGENTS - Disclosed is an ethylene-based polymer with a density from about 0.90 to about 0.94 in grams per cubic centimeter, with a molecular weight distribution (M07-21-2011
20110184131Circulating Fluidized Bed Reactor - A continuous gas phase circulating bed reactor, including: a riser for contacting a catalyst and a first gas composition comprising an olefin to form a polyolefin under fast-fluidization regime or a dilute-phase pneumatic conveying regime conditions; a downer for contacting the catalyst and a second gas composition comprising an olefin to form additional polyolefin under fast fluidization regime or a dilute-phase pneumatic conveying regime conditions; and a transport section for conveying at least a portion of the catalyst, polyolefin, and additional polyolefin from the downer to the riser. Also disclosed is a polymerization process using such a circulating bed reactor.07-28-2011
20110184129METHOD FOR PRODUCING ETHYLENE COPOLYMERS - Process for the continuous preparation of ethylene copolymers by free-radical copolymerization of ethylene and at least one comonomer (b) selected from among ethylenically unsaturated carboxylic acids, esters of ethylenically unsaturated carboxylic acids, ethylenically unsaturated phosphonic acids and esters of ethylenically unsaturated phosphonic acids, wherein one or more inhibitors are metered separately from ethylene and the comonomer or comonomers (b) into the reaction mixture.07-28-2011
20130030132PROCESS FOR PREPARING POLYOLEFIN - The invention relates to a process for preparing polyolefin in a loop reactor. The polymer is prepared by polymerizing olefin monomers in the presence of a catalyst to produce a polyolefin slurry while pumping said slurry through said loop reactor by means of a pump. The present process is characterized in that the catalyst is fed in the loop reactor at a distance to the pump. The invention allows production of the polymer with advantageous properties while leading to fewer blockages of the reactor.01-31-2013
20090326171PROCESS FOR THE PREPARATION OF HIGH PERFORMANCE POLYPROPYLENE - The invention discloses a process for preparing high-performance propylene polymers, the process utilizing a high activity, highly stereoselective Ziegler-Natta catalyst and two or more stages of polymerization carried out under different hydrogen concentrations to prepare propylene polymers having broad molecular weight distribution, wherein non-unifomess of isotacticity of molecular chains of the final propylene polymers is improved by adjusting or controlling stereoselectivity of catalytic active sites under different hydrogen concentrations, namely, making the low molecular weight fraction of the polymers having a higher isotacticity and making the high molecular weight fraction of the polymers having a lower isotacticity, thereby overcoming the drawbacks of the propylene polymers having broad molecular weight distribution known in the art. The resulting final polymers have excellent combined properties, in particular, remarkably improved mechanical properties.12-31-2009
20130085241Methods of Improving Crosslinkability of Polyethylene Polymer Comprising Polar Comonomer and Polymer Compositions - Processes for producing high pressure polyethylene and processes for increasing the crosslinkability of high pressure polyethylene are disclosed. The processes comprise controlling particular reaction parameters that have been found to promote crosslinkability in the resulting high pressure polyethylene. High pressure polyethylenes having improved crosslinkability are also disclosed.04-04-2013
20100056734GASEOUS PHASE FLUIDIZED-BED REACTOR - Gas-phase fluidized-bed reactor for polymerizing ethylenically unsaturated monomers, comprising a reactor chamber (03-04-2010
20130035459REACTOR - The present invention relates to a reactor, and in particular to a slurry loop polymerisation reactor which comprises: 02-07-2013
20130035458High Activity Catalyst Compositions Containing Silicon-Bridged Metallocenes with Bulky Substituents - The present invention discloses catalyst compositions employing silicon-bridged metallocene compounds with bulky substituents. Methods for making these silicon-bridged metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins also are provided.02-07-2013
20130041117APPARATUS FOR PRODUCING METHACRYLIC POLYMER AND PRODUCTION METHOD THEREOF - Disclosed is an apparatus for producing a high-quality methacrylic polymer with good productivity, comprising a complete mixing type reactor 02-14-2013
20120264891METHOD FOR PRODUCING A CATALYST SLURRY BLEND - The present invention relates to a method for producing a catalyst slurry blend suitable for polymerizing ethylene in an ethylene polymerization loop reactor for obtaining an at least trimodal polyethylene product, comprising the steps of: 10-18-2012
20100144984Slurry phase polymerisation process - A process comprising polymerising in a loop reactor of a continuous tubular construction an olefin monomer optionally together with an olefin comonomer in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the average internal diameter of at least 50% of the total length of the reactor is at least 650 millimeters, the solids concentration in the reactor is at least 15 volume % and having a particle size distribution such that (D90−D10)/D50 is less than 2.06-10-2010
20100041840METHOD FOR PREPARING AN UNSATURATED ETHYLENE-DIENE COPOLYMER - The present invention relates to a method for preparing an unsaturated ethylene-diene copolymer by high pressure radical-initiated polymerisation, said method providing an improved conversion of added diene into pendant vinyl groups.02-18-2010
20090156758Gas-Phase Process for the Poymerization of Olefins - A process for the gas-phase polymerization of one or more alpha-olefins in the presence of a polymerization catalyst system, the process comprising: a) contacting in a continuous way a gas comprising one or more of said alpha-olefins with said catalyst system in a gas-phase tubular reactor at a temperature from 30° C. to 130° C. in order to obtain a polymerization degree up to 500 grams per gram of catalyst system; b) feeding in continuous the prepolymer from step a) to a successive gas-phase polymerization reactor; wherein said gas-phase tubular reactor has a length/diameter ratio higher than 100.06-18-2009
20100105847PLUG FLOW BULK POLYMERIZATION OF VINYL MONOMERS - A process for continuous bulk polymerization is disclosed that includes providing a plug flow reactor comprising a primary loop reactor including a loop for recirculating a portion of a polymer-in-progress at a polymer flow rate back to a reactor in the primary loop reactor, introducing at least one monomer into the primary recirculation loop reactor at a monomer flow rate, polymerizing the monomer in the primary recirculation loop reactor in the presence of an initiator by way of a free-radical polymerization to form a polymer-in-progress, and recirculating a first portion of the polymer-in-progress through the loop into a reactor in the primary loop reactor to combine with the monomer at a ratio of polymer flow rate to monomer flow rate that is greater than 5.04-29-2010
20090198025Method for seed bed treatment before a polymerization reaction - In some embodiments, a method in which at least one continuity additive (“CA”) and a seed bed are pre-loaded into a reactor, and a polymerization reaction is optionally then performed in the reactor. In other embodiments, at least one flow improver, at least one CA, and a seed bed are pre-loaded into a reactor. Pre-loading of a reactor with a CA can significantly improve continuity of a subsequent polymerization reaction in the reactor during its initial stages, including by reducing sheeting and fouling. The CA can be pre-loaded in dry form (e.g., as a powder), or in liquid or slurry form (e.g., as an oil slurry). To aid delivery of a dry CA to the reactor and combination of the dry CA with a seed bed in the reactor, the dry CA can be combined with a flow improver and the combination of CA and flow improver then loaded into the reactor. Alternatively, the CA and flow improver can be sequentially loaded into the reactor, and then mixed together (and mixed with a seed bed) in the reactor after both the CA and flow improver have been separately loaded into the reactor.08-06-2009
20100331500REDUCED BLOCKAGE WHEN TRANSFERRING POLYMER PRODUCT FROM ONE REACTOR TO ANOTHER - This invention is related to the field of olefin polymerisation in double loop reactors and especially to the polymerisation of olefins with very active catalyst systems. It discloses a method for reducing blockage when transferring polymer product from the first loop to the second loop of a double loop reactor.12-30-2010
20110015353Process for Preparing a Polyethylene Resin in a Double Loop Reactor with a Mixture of Bis-indenyl and Bis-tetrahydroindenyl - 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.01-20-2011
20090270567Olefin Oligomerization - Provided is a method of oligomerizing alpha olefins. In an embodiment, an oligomerization catalyst system is contacted in at least one continuous reactor with a feed comprising olefins; an effluent comprising product olefins having at least four carbon atoms is withdrawn from the reactor; the oligomerization catalyst system comprises iron or cobalt, or combinations thereof; and the single pass conversion of ethylene is at least about 40 weight percent among product olefins having at least four carbon atoms. In another embodiment, the single pass conversion of ethylene comprises at least about 65 weight percent among product olefins having at least four carbon atoms. In another embodiment, product olefins of the effluent having twelve carbon atoms comprise at least about 95 weight percent 1-dodecene. In another embodiment, product olefins comprise at least about 80 weight percent linear 1-alkenes. In another embodiment, product olefins comprise at least about 20 weight percent alpha olefins having from about 8 to about 20 carbon atoms. In another embodiment, the oligomerization catalyst system provided comprises a selective 1-hexene (S1H) catalyst.10-29-2009
20090270566Olefin Polymerization Processes and Catalysts for Use Therein - Polymerization process and polymers formed therefrom are described herein. The polymerization processes generally include introducing an olefin monomer into a reaction vessel, introducing a single-site transition metal catalyst into the reaction vessel, introducing a multi-functional block copolymer non-ionic surfactant into the reaction vessel, contacting the olefin monomer with the catalyst system in the presence of the non-ionic surfactant within the reaction vessel under polymerization conditions to form a polyolefin and withdrawing the polyolefin from the reaction vessel.10-29-2009
20110021725Production method and production apparatus of particulate water absorbing agent containing water absorbent resin as main component - An apparatus (01-27-2011
20090234082Extrusion Coating Composition - The invention relates to an extrusion coating composition comprising an ethylene copolymer.09-17-2009
20090012245CARBONYL HYDROGENATED KETONE ALDEHYDE RESINS, DEVOID OF FORMALDEHYDE, BASED ON FORMALDEHYDE AND ASSOCIATED PRODUCTION METHOD - The invention relates to formaldehyde-free, carbonyl-hydrogenated ketone-aldehyde resins based on formaldehyde and having a low fraction of crystallizable compounds, low viscosity, very low color number, and very high heat stability and light stability, and also to a process for preparing them.01-08-2009
20100087605PROCESS FOR PRODUCTION OF THERMOPLASTIC COPOLYMER - A process for continuously producing a thermoplastic copolymer, in which a copolymer (A) containing unsaturated carboxylic acid alkyl ester units and unsaturated carboxylic acid units is produced and in succession heat-treated to perform intramolecular cyclization reaction by dehydration and/or dealcoholization reaction, for producing a thermoplastic copolymer (B) containing glutaric anhydride units and the unsaturated carboxylic acid alkyl ester units. The obtained copolymer is excellent in heat resistance and colorless transparency and very small in foreign matter content.04-08-2010
20120238712USE OF HYDROGEN SCAVENGING CATALYSTS TO CONTROL POLYMER MOLECULAR WEIGHT AND HYDROGEN LEVELS IN A POLYMERIZATION REACTOR - The present invention provides dual catalyst systems containing a metallocene catalyst and a hydrogen scavenging catalyst, and polymerization processes employing these dual catalyst systems. Due to a reduction in hydrogen levels in the polymerization processes, olefin polymers produced from these polymerization processes may have a higher molecular weight, a lower melt index, and higher levels of unsaturation.09-20-2012
20120172548POLYOLEFIN AND PREPARATION METHOD THEREOF - A polyolefin has 1) a density in the range of 0.93 to 0.97 g/cm07-05-2012
20120190803HALF-METALLOCENE COMPOUNDS AND CATALYST COMPOSITIONS - The present invention provides polymerization catalyst compositions employing half-metallocene compounds with a heteroatom-containing ligand bound to the transition metal. Methods for making these hybrid metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins also are provided.07-26-2012
20110144290NANO-LINKED HETERONUCLEAR METALLOCENE CATALYST COMPOSITIONS AND THEIR POLYMER PRODUCTS - The present invention provides polymerization catalyst compositions employing novel heterodinuclear metallocene compounds. Methods for making these new dinuclear metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins are also provided.06-16-2011
20090292084Process for alkoxylation with DMC catalysts in a loop reactor with ejector - The invention relates to a process for preparing polyethers of the formula (I)11-26-2009
20100113713STEAM HEATED POLYESTER PRODUCTION PROCESS - Processes for making polyesters in a polyester production facility are disclosed, that include the steps of forming a reaction medium comprising at least one monomer that includes terephthalic acid (TPA) and/or an ester derivative of TPA; subjecting at least a portion of the reaction medium to one or more chemical reactions in the polymer production facility to thereby produce the polyester; and heating the reaction medium at one or more locations in the polyester production facility, wherein at least 50 percent of the total energy input employed for the heating of the reaction medium is provided by indirect heat exchange between the reaction medium and steam.05-06-2010
20110301307Ethylene Polymerization in a High Pressure Reactor with Improved Initiator Feeding - Process for the preparation of ethylene homopolymers or copolymers in a high pressure reactor with at least two spatially separated initiator injection points by polymerizing ethylene and optionally further monomers in the presence of at least two different mixtures of free-radical polymerization initiators at from 100° C. to 350° C. and pressures in the range of from 160 MPa to 350 MPa, wherein the process comprises the following steps: 12-08-2011
20090023872Polypropylene series reactor - Aspects of the invention are directed to a process for producing polypropylene comprising: providing series reactors comprising a first and a second loop allowing flow of polypropylene, catalyst, hydrogen and propylene there between, wherein each loop comprises from six to eight legs, each leg having fluid connections there between; injecting into the first loop an amount of a catalyst, propylene and optionally hydrogen; withdrawing polypropylene, and unreacted propylene and optionally unreacted hydrogen from the first loop and injecting the polypropylene, and unreacted propylene and optionally unreacted hydrogen into the second loop; and providing a propylene/polypropylene separator fluidly connected to the second loop and isolating polypropylene therefrom. In one embodiment a recycle conduit is provided between the propylene/polypropylene separator and the second loop allowing the recycling of unreacted propylene and optionally hydrogen into the second loop.01-22-2009
20110288247Continuous Take Off Technique and Pressure Control of Polymerization Reactors - Techniques and systems for producing a polyolefin using reactors in series are described. Described embodiments include techniques and systems for polymerizing a monomer in a first polymerization reactor to form a first polyolefin, discharging a first slurry continuously from the first polymerization reactor to a second polymerization reactor, and discharging a second slurry continuously from the second polymerization reactor. Using continuous take-off devices disposed on either or both reactors, pressure control may be attained such that the rate of transfer between and withdrawal from both reactors are within a desired range.11-24-2011
20090143546Double Loop Technology - A method for controlling the injection of catalyst slurry in a polymerization reactor is described herein. The method includes the preparation of polyethylene with a solid catalyst and a hydrocarbon diluents. The method includes providing solid catalyst and a hydrocarbon diluent in one or more storage vessels such that a catalyst slurry is obtained in said vessel, transferring said catalyst slurry from said storage vessel to a mixing vessel wherein said catalyst slurry is diluted for obtaining a suitable concentration for use in a polymerization reaction, pumping said diluted catalyst slurry at a controlled flow rate from said mixing vessel to said polymerization reactor through one or more conduits, by means of a membrane pump provided in each of said conduits, and the membrane pump is controllable as a function of reactant concentration within the polymerization reactor.06-04-2009
20110294968METHOD FOR PRODUCING POLYMERS AND REACTOR FOR CARRYING OUT SAID METHOD - The invention relates to a process for preparing polymers from monomers and/or oligomers by adding a liquid comprising the monomers and/or oligomers dropwise to a continuous liquid phase in a reactor, the continuous liquid phase being immiscible with the liquid comprising the monomers and/or oligomers, and the monomers and/or oligomers reacting in the continuous liquid phase to give the polymer. The liquid comprising the monomers and/or oligomers is shaped to droplets outside the continuous liquid phase, which are subsequently introduced into the continuous liquid phase. The invention further relates to a reactor for performing the process, comprising a tube through which a continuous liquid phase flows, and means of generating droplets, the means of generating droplets being arranged such that the droplets are generated outside the continuous liquid phase and then introduced into the continuous liquid phase.12-01-2011
20110294967Method for Ethylene Polymerization in a Tubular Reactor with Reduced Output - Process for the preparation of ethylene homopolymers or copolymers in the presence of free-radical polymerization initiators at from 100° C. to 350° C. and pressures in the range of from 160 MPa to 350 MPa in a tubular reactor with at least two spatially separated initiator injection points, wherein injecting initiator rises the temperature of the reaction mixture in the reaction zone following the injection point, and the first initiator injection point of the tubular reactor is not provided with initiator or is provided with so little initiator that the temperature of the reaction mixture does not rise more than 20° C. in the first reaction zone and method for reducing the output of a high pressure tubular reactor for the homo- or copolymerization of ethylene in the presence of free-radical polymerization initiators with at least two initiator injection points, wherein feeding of free-radical polymerization initiator to the first initiator injection point is discontinued or reduced to a level that the temperature of the reaction mixture in the first reaction zone does not rise more than 20° C.12-01-2011
20080221281CONTINUOUS PROCESS AND SYSTEM OF PRODUCING POLYETHER POLYOLS - A continuous process and system for producing polyether polyols that allows for continuously adding an unreacted oxide to a loop reactor while adding at least one thermally deactivating catalyst capable of thermally deactivating prior to decomposition of polyether polyol which can allow for greater concentrations of unreacted oxides and/or a rate of reaction in the loop reactor is at a rate at least two times faster than a rate of reaction in a loop reactor containing less than 14 weight percent unreacted oxide. In a preferred embodiment, the catalyst is a double metal cyanide catalyst and a plug flow reactor is formed in series with the loop reactor wherein neither reactor contains a vapor space.09-11-2008
20110201766Method and System to Add High Shear to Improve an Ionic Liquid Catalyzed Chemical Reaction - In an embodiment, a method is disclosed to increase the activity of an ionic liquid catalyst comprising emulsifying the ionic liquid catalyst with one or more liquid components. In an embodiment, a method is disclosed comprising introducing into a reaction zone a monomer feed and a reduced amount of ionic liquid catalyst and controlling an amount of shear present in the reaction zone to maintain a desired conversion reaction of the monomer. In an embodiment, a catalyzed reaction system is disclosed comprising a reactor configured to receive one or more liquid components and ionic liquid catalyst; a device coupled to the reactor for adding high shear to the liquid components and ionic liquid catalyst; and a controller coupled to the device for adding high shear and configured to control the amount of shear added to a catalyzed reaction zone to maintain a conversion reaction.08-18-2011
20090099323Melamine-formaldehyde resin solution and process for producing the same - A melamine-formaldehyde resin solution having a formaldehyde/melamine ratio smaller than or equal to 04-16-2009
20090171041NANO-LINKED METALLOCENE CATALYST COMPOSITIONS AND THEIR POLYMER PRODUCTS - The present invention provides polymerization catalyst compositions employing novel dinuclear metallocene compounds. Methods for making these new dinuclear metallocene compounds and for using such compounds in catalyst compositions for the polymerization and copolymerization of olefins are also provided.07-02-2009
20110263799PROCESS FOR THE CONTINUOUS PRODUCTION OF POLYESTERS - A continuous process for the ring-opening polymerisation of cyclic ester monomers to form aliphatic polyesters at a temperature between 100-240° C. which includes a) continuously providing cyclic ester monomer and polymerisation catalyst to a continuous mixing reactor, the reactor being operated at conditions effective for polymerisation to form a pre-polymerised reaction mixture,10-27-2011
20100113712STEAM HEATED POLYESTER PRODUCTION PROCESS - Processes for making polyesters in a polyester production facility are disclosed, that include the steps of: forming a reaction medium comprising at least one monomer that includes terephthalic acid (TPA) and/or an ester derivative of TPA; subjecting at least a portion of the reaction medium to one or more chemical reactions in the polyester production facility to thereby produce the polyester; generating high-pressure steam having a pressure of at least 5 megapascals; heating one or more process fluid streams of the polyester production facility by indirect heat exchange with the high-pressure steam, wherein the process fluid streams include any stream that is formed predominately of the reaction medium and/or the at least one monomer; heating a heat transfer medium (HTM) via indirect heat exchange with the high-pressure steam to thereby form heated HTM; and heating at least a portion of the process fluid streams by indirect heat exchange with the heated HTM.05-06-2010
20100249343Process for Polymerising or Oligomerising a Hydrocarbon - A process for polymerizing or oligomerising a hydrocarbon includes feeding at a low level a liquid hydrocarbon reactant into a bulk liquid phase comprising polymeric or oligomeric product admixed with a catalyst. The liquid hydrocarbon reactant is allowed to vapourise to form bubbles rising through the bulk liquid phase and to polymerise or oligomerise to form the polymeric or oligomeric product, with the rising bubbles creating turbulence in the bulk liquid phase, thereby mixing the bulk liquid phase. Gaseous components comprising any unreacted vapourised hydrocarbon reactant and any gaseous product that may have formed are withdrawn from a head space above the bulk liquid phase. Liquid phase from the bulk liquid phase is withdrawn to maintain the bulk liquid phase at a desired level.09-30-2010
20090069514PRODUCTION METHOD OF OPTICAL TRANSMISSION MEDIUM - A polymerization initiator, a first polymerizable compound, and a second polymerizable compound are poured into a hollow of a first member (03-12-2009
20100267903Process for the preparation of propylene random copolymers - A process for the preparation of a propylene random copolymer, wherein propylene is polymerised with ethylene and/or a C4-C20 alpha-olefin in the presence of a catalyst system comprising solid catalyst particles, wherein the solid catalyst particles (a) have a specific surface area of less than 20 m10-21-2010
20100144986CONTINUOUS PRODUCTION OF POLYAMIDES - Polyamides, e.g., polyhexamethylene adipamide, are continuously produced via the following stages:06-10-2010
20120088890BRIDGED METALLOCENE CATALYST SYSTEMS WITH SWITCHABLE HYDROGEN AND COMONOMER EFFECTS - The present invention provides polymerization processes utilizing an ansa-metallocene catalyst system for the production of olefin polymers. Polymers produced from the polymerization processes have properties that vary based upon the presence or the absence of hydrogen and/or comonomer in the polymerization process.04-12-2012
20130217841CONTINUOUS FLOW POLYMERISATION PROCESS - The present invention relates to a process for continuously preparing polymer by RAFT solution polymerisation, the process comprising: introducing into a flow reactor a reaction solution comprising one or more ethylenically unsaturated monomers, RAFT agent, non-reactive solvent and free radical initiator; and promoting RAFT polymerisation of the one or more ethylenically unsaturated monomers within the reactor so as to form a polymer solution that flows out of the reactor.08-22-2013
20100120998CATALYST COMPONENT FOR THE POLYMERIZATION OF OLEFINS - A catalyst component for the polymerization of olefins comprises Mg, Ti, halogen, and an alpha-omega-diether represented by the general formula: (RO)—(CR05-13-2010
20100120999Olefin Polymerization Process with Optimized Product Discharge - The present invention relates to a polymerization process for producing olefin polymers in a loop reactor comprising the steps on introducing into the loop reactor one or more olefin reactants, polymerization catalysts and diluents, and while circulating said reactants, catalysts and diluents, polymerizing said one or more olefin reactants to produce a polymer slurry comprising essentially liquid diluent and solid olefin polymer particles, said process further comprising one or more cycles of: (a) allowing said polymer slurry to settle in one or more setting legs connected to said reactor, and (b) discharging from a setting leg a predetermined volume of polymer slurry substantially equal to the volume of polymer slurry settled in said settling leg since its previous discharge.05-13-2010
20120108765POLYMERIZATION CATALYSTS FOR PRODUCING POLYMERS WITH LOW MELT ELASTICITY - The present techniques relate to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene compound comprising bridging η05-03-2012
20120108764HALF-METALLOCENE CATALYST COMPOSITIONS AND THEIR POLYMER PRODUCTS - The present invention provides polymerization catalyst compositions employing half-metallocene compounds with a heteroatom-containing ligand bound to the transition metal. Methods for making these hybrid metallocene compounds and for using such compounds in catalyst compositions for the polymerization and copolymerization of olefins are also provided.05-03-2012
20090088537Polymerization catalysts for producing polymers with high comonomer incorporation - The present techniques relate to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene compound comprising bridged η04-02-2009
20090163678Bulk homogeneous polymerization process for ethylene propylene copolymers - Provided are bulk homogeneous polymerization processes for producing ethylene propylene random copolymers. The process includes contacting in a reactor or in a series of reactors propylene monomer, ethylene comonomer with one or more catalyst systems and optional solvent (present at less than 40 wt %), wherein the reactor train is at a temperature of between 65° C. and 180° C. and at a pressure no lower than 10 MPa below the cloud point pressure of the polymerization system and less than 1500 MPa, and wherein the polymerization system for the reactor train is in its dense fluid state to form a polymer reactor effluent including a homogeneous fluid phase polymer-monomer mixture in the reactor train; and wherein the resultant copolymer product comprises between 10 wt % and 20 wt % randomly distributed ethylene and the concentration of total region defects in the continuous propylene segments of the random EP copolymer is between 40 and 150% greater than in a copolymer of equivalent melt flow rate and wt % ethylene polymerized by a solution polymerization process.06-25-2009
20090292085Polymerization processes for broadened molecular weight distribution - Provided are methods of producing polymers with broadened molecular weight and/or composition distribution in a continuous homogeneous polymerization system utilizing reactor temperature gradients, reactor polymer concentration gradients, monomer concentration gradients, catalyst concentration gradients, and combinations thereof in the polymerization reactor. Such methods are particularly suitable when utilizing metallocene catalysts and other single-site catalysts, which generally produce polymers with narrow molecular weight and composition distribution.11-26-2009
20110269922GAS-PHASE POLYMERIZATION OF ALPHA-OLEFIN - A method for preparing polyolefin from alpha-olefin with high productivity using an internal circulating fluidized bed polymerization reactor is disclosed. The method for gas-phase polymerization of alpha-olefin comprising the steps of: supplying circulation gas including one or more alpha-olefins and inert gas into a polymerization reactor; polymerizing the alpha-olefin to polyolefin in two separated polymerization areas in the polymerization reactor; and discharging produced polyolefin from the polymerization reactor. The polymerization reactor is divided into the two polymerization areas by a draft tube, and an inside of the draft tube forms a riser where growing polyolefin polymers move up in fast fluidization, and an outside of the draft tube forms an annulus where the polyolefin polymers passing the riser move down by gravity, and the polyolefin polymers passing the annulus are introduced to a lower part of the riser again, so that the polyolefin polymers are polymerized during circulating between the riser and the annulus.11-03-2011
20080269431Apparatus and Method for Continuously Carried Out Equilibrium Reactions - The invention relates to an apparatus and a process for carrying out equilibrium reactions continuously.10-30-2008
20080269432Device For Injecting Successive Layers Of Fluid In A Circulating Fluidised Bed And Methods Using Same - Device for injecting fluid in successive layers into a rotating fluidized bed and methods for catalytic polymerization, drying or other treatments of solid particles or for catalytic conversion of fluids, in which a succession of injectors (10-30-2008
20080275195Polymerization Process - The present invention relates to a process for continuously preparing water-absorbing polymers by mixing a monomer solution with at least one crosslinker and polymerizing the resulting mixture, wherein the residence time of the mixture between the addition of the at least one crosslinker and the entry into the polymerization reactor is less than 180 seconds, and also to an apparatus for performing the process.11-06-2008
20090005520Fouling prevention in polymerization reactors - Reactor designs and processes for operating such reactor designs to minimize or eliminate fouling in homogeneous polymerization processes (solution and supercritical). The process includes providing a reactor with one or more feed entry ports, wherein the reactor feed components are fed through each of the one or more feed entry ports at a linear velocity of greater than or equal to 0.3 m/min. The one or more feed entry ports may also be optionally extended beyond the interior reactor wall by greater than or equal to 2% of the internal radius of the reactor to further decrease the propensity for fouling. A stirred reactor may also include a stirrer feed port for purging the stirrer with a stirrer purge stream at a linear velocity of greater than or equal to 0.3 m/min to decrease stirrer fouling.01-01-2009
20080207851Method for the Production of Polymers - The present invention relates to a process for preparing polymers by polycondensation catalysed by transition metals. These polymers are of great importance in, in particular, the fast-growing field of organic semiconductors. The polymers obtained by the process of the invention can be prepared with greater reproducibility and in higher purity than polymers obtained according to the prior art.08-28-2008
20110207898Method for Transitioning Between Ziegler-Natta and Metallocene Catalysts in a Bulk Loop Reactor for the Production of Polypropylene - Polymerization processes in a bulk loop reactor are described herein. In particular, a method of contacting a flow of metallocene with a flow of propylene is provided. This method includes directing the flow of metallocene towards a junction, directing the flow of propylene towards the junction and maintaining a portion of the flow of metallocene separate from a portion of the flow propylene within a portion of the junction downstream of the flow of propylene into the junction. In another embodiment, a method of introducing a quantity of antifouling agent into a catalyst mixing system is provided. In this embodiment a portion of the antifouling agent is introduced at or downstream of a point of contact of a stream of propylene with a stream of catalyst. The antifouling agent may be a member, alone or in combination with other members, selected from Stadis 450 Conductivity Improver, Synperonic antifouling agent, and Pluronic antifouling agent.08-25-2011
20100267904Method and Device for Optimising Catalyst Supply to a Polymerisation Reactor - Methods for supplying a catalyst to an ethylene slurry loop polymerization reactor and polymers formed therefrom are described herein. The method generally includes preparing a catalyst slurry in a preparation vessel wherein the slurry includes a hydrocarbon diluent liquid which contains a Ziegler-Natta catalyst; supplying the catalyst slurry from the preparation vessel to a buffer vessel; withdrawing the catalyst slurry from the buffer vessel and supplying the catalyst slurry to a slurry loop polymerization reactor in which ethylene is polymerized; mixing a co-catalyst with the Ziegler Natta catalyst in the slurry prior to the supplying of the catalyst slurry to the slurry loop polymerization reactor; and controlling the transfer of catalyst slurry from the preparation vessel to the buffer vessel and the withdrawal of catalyst slurry from the buffer vessel to maintain the level of catalyst slurry in the buffer vessel substantially constant relative to the level of catalyst slurry in the preparation vessel.10-21-2010
20110224387PREPARATION OF PROPYLENE COPOLYMER WITH DYNAMICALLY OPERATED REACTOR - The present invention relates to a process for the preparation of a propylene copolymer P1 having ethylene-derived comonomer units, which comprises the following steps: (i) introducing propylene, ethylene, and hydrogen into a polymerisation reactor R1, wherein the ethylene is fed to the polymerisation reactor R1 in a periodically varying amount, (ii) preparing the propylene copolymer in the polymerisation reactor R1 in the presence of a catalyst.09-15-2011
20100004407Process for the Production of Polyethylene and Ethylene Copolymers - The invention provides a process and an apparatus for the high pressure polymerization of ethylene in which a jet pump is used to pump a fluid into a polymer/monomer product mixture leaving a bumped tubular reactor. The fluid may be recycled monomer or another fluid such as a modifier.01-07-2010
20090326169Process for the Preparation of Ethylene Polymers using a Number of Reactors Arranged in Series - The present invention relates to a process for the preparation of ethylene polymers using a number of reactors arranged in series comprising the steps in which 12-31-2009
20090326170Process for Improving the Polymerization of Ethylene and One or More Optional Comonomer(s) in a Polymerization Loop Reactor - The present invention relates to a process for improving the polymerization of ethylene and one or more optional co-monomer(s) in a polymerization loop reactor characterized in that said process comprises the step of controlling the hydrogen/monomer ratio along the path of the reactor by multiple, spatially separated, feeding of hydrogen along the path of the loop reactor. In particular, the invention provides a process for controlling, and preferably narrowing, the molecular weight distribution of the produced polymer particles. In another aspect, the invention relates to a polymerization loop reactor suitable for the polymerization process of ethylene and an optional olefin co-monomer, wherein the molecular weight distribution of the produced ethylene polymer can be controlled.12-31-2009
20090198023Polyethylene Materials Prepared Using Mixed Ziegler-Natta Catalysts Systems - A polyethylene may be prepared using a mixture of a silica supported catalyst and a magnesium chloride supported catalyst. By changing the ratio of the two catalysts, the polyethylene produced may have a varying bulk density and shear response. The method allows for the tuning or targeting of properties to fit a specific application, such as a blow molding or vapor barrier film.08-06-2009
20110144289Multi reactor process - This invention relates to the polymerization of ethylene polymers using a continuously stirred tank reactor (CSTR) that is connected in series to a tubular reactor. The tubular reactor receives a polymer solution from the CSTR. Further polymerization in the tubular reactor improves production efficiencies, particularly with respect to lowering the amount of energy required to recover the polymer and residual comonomer from the solution. The use of tempered i.e. (heated) ethylene in the tubular reactor has been discovered to mitigate gel problems and lower/reduce levels of hexane extractables.06-16-2011
20090054605Apparatus and Method for Polymer Synthesis Using Arrays - A polymer synthesis apparatus (02-26-2009
20110230628SPOUTED BED DEVICE, POLYOLEFIN PRODUCTION SYSTEM WITH SPOUTED BED DEVICE, AND POLYOLEFIN PRODUCTION PROCESS - A spouted bed device according to the present invention includes a vertically extending cylinder; a decreasing diameter member which is formed on the cylinder, has an inside diameter that decreases progressively downward, and has a gas inlet orifice at a bottom end thereof; and a tubular portion which extends downward from an edge of the gas inlet orifice. A spouted bed is formed in a treatment zone enclosed by a top surface of the decreasing diameter member and an inner wall of the cylinder above the decreasing diameter member.09-22-2011
20090018284REACTOR SYSTEM WITH OPTIMIZED HEATING AND PHASE SEPARATION - A reactor system operable to facilitate a chemical reaction in a reaction medium flowing therethrough. The reactor system includes a heat exchanger for heating the reaction medium and a disengagement vessel for disengaging vapor from the heated reaction medium.01-15-2009
20100273961Slurry Loop Reactors - Reactor systems suitable for the polymerization of an olefin monomer including first and second loop reactors effective for the polymerization of an olefin monomer and polymers formed therefrom are described herein. Each of said reactors generally include at least one settling leg connected to said reactor for receiving polymer slurry from said reactor and sequentially discharging settled polymer from said at least one settling leg to withdraw said polymer slurry from said reactor; a transfer line extending from the outlet at least one first reactor settling leg to an inlet for said second loop reactor; a flash line extending from said transfer line at a valve location intermediate said first reactor settling leg and said inlet for said second reactor; and a multiway valve located in said transfer line at said valve location intermediate said first reactor settling leg and the inlet to said second reactor and having one position in which said multiway valve provides for the flow of polymer slurry through said transfer line to said second reactor and another position in which said first reactor settling leg is connected to said flash line for the discharge of polymer slurry from said first reactor settling leg to said flash line and removal of said polymer from said polymer system.10-28-2010
20100273960SLURRY PHASE POLYMERISATION PROCESS - Process for producing a multimodal polyethylene in at least two loop 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, one polymer being made in the presence of the other in either order, wherein 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%.10-28-2010
20090281255CONTINUOUS PROCESS FOR THE PRODUCTION OF VINYL CHLORIDE (CO)POLYMERS - Polymerization process comprising the steps of: (a) reacting an aqueous suspension comprising initiator, vinyl chloride, and optionally one or more co-monomers in a continuous stirred tank reactor; and (b) further reacting the resulting suspension in at least one second reactor; wherein the conversion level of vinyl chloride in the continuous stirred tank reactor of step (a) is from 10 to 60 wt %.11-12-2009
20100261855Method of Operating a High Pressure Ethylene Polymerisation Unit - The invention relates to a method of operating a high pressure ethylene polymerisation unit comprising a tubular reactor, the method characterised in that the electrical conductivity of the aqueous cooling medium is monitored in at least one location. Furthermore, the invention also covers a high pressure ethylene polymerisation unit comprising a tubular reactor, the unit characterised in that one or more cooling circuits comprise an electrical conductivity metre. The use of such a polymerisation unit is also disclosed.10-14-2010
20100152395PROCESS FOR PREPARING A POLYMER - The present invention relates to a process which comprises preparing polymers. The process uses an appropriate installation, and may comprise determining at least one parameter of a physical and/or chemical conversion. The invention also relates to a corresponding screening process. According to this process, a polymerization reaction medium is made to flow in a tubular flow member (06-17-2010
20130123442PUMP FOR LOOP REACTOR - The present invention relates the use of a pump in a loop reactor for the production of polyethylene, as well as a reactor comprising such pump and methods for producing polyolefin by means of such reactor. The pump according to the invention is characterized in that it is an axial flow impeller circulation pump, wherein the impeller comprises 6 blades and wherein the pump is fixed on a spring supported frame. Use of the pump according to the present invention allows for preparation of homogeneous polyethylene products that meet high quality standards from the complicated ethylene polymerization mixtures while at the same time being produced with low energy consumption.05-16-2013
20130123443Process for preparing polyolefins and use of antifouling agents therein - The present invention relates to a process of preparing a polyethylene in a loop reactor in the presence of antifouling agent comprising the steps of: 05-16-2013
20100227986Methods of Catalyst Activation - A method comprising preparing a multi-component catalyst system comprising a catalyst and a cocatalyst, and adjusting the level of at least one component of the catalyst system to maintain a user-desired level of catalyst activity throughout a process, wherein the component comprises a catalyst activator and wherein the catalyst activator comprises the catalyst or the cocatalyst. A method comprising contacting a polymerization catalyst system comprising a Ziegler-Natta catalyst and a cocatalyst with a catalyst activator at least twice during a polymerization process, wherein the polymerization process is carried out in a reactor system comprising multiple reactor types.09-09-2010
20100234541 Process to Reduce Polyolefins with Extra Low Impurity Content - A process for producing polyolefins, which includes polymerizing at least one olefin monomer, separating at least a part of the reaction mixture, dividing the separated reaction mixture into a polymer-lean fraction and a polymer-rich fraction, and subjecting at least a part of the polymer-lean fraction to a purification step prior to recycling back to the polymerization of at least one olefin monomer. The obtained polyolefins particularly have a low content of volatile low molecular weight compounds, a low content of low-molecular weight polyolefin waxes and a low content of residues derived from the catalyst employed.09-16-2010
20120130026MITIGATION OF ELASTOMER REACTOR FOULING USING MECHANICAL VIBRATION - Method of reducing fouling in an elastomer polymerization process that includes providing a reactor capable of housing an industrial-scale elastomer polymerization reaction, and applying a mechanical force to the reactor so as to create a vibration in at least one wall of the reactor, in which fouling is reduced in the reactor. In one embodiment the reaction is an industrial scale butyl polymerization reaction and the reactor is a butyl polymerization reactor.05-24-2012
20090076231Production of polymers in a conical reactor - The present invention provides a process for the preparation of polymer which comprises the steps of i) feeding an aqueous mixture comprising a monoethylenically unsaturated monomer or a mixture of monoethylenically unsaturated monomers and an initiator into the top of a reactor ii) polymerizing the monoethylenically unsaturated monomer to form a gel-like aqueous mixture comprising the polymer, iii) squeezing the gel-like aqueous mixture comprising the polymer out of the bottom of the reactor using inert gas, wherein the reactor is either a vertical fully conical reactor having an angle (alpha) between top diameter (d03-19-2009
20100144985Slurry phase polymerisation process - Process comprising polymerising in a loop reactor of a continuous tubular construction an olefin monomer optionally together with an olefin comonomer in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent, wherein the average internal diameter of at least 50% of the total length of the continuous tubular loop reactor is at least 700 mm wherein the HMW polymer is produced in a reactor upstream of the LMW polymer reactor and the ratio of the average internal diameter of the HMW reactor to the average internal diameter of the LMW reactor is between 0.8 and 1.4.06-10-2010
20130217842High Activity Catalyst Compositions Containing Silicon-Bridged Metallocenes With Bulky Substituents - The present invention discloses catalyst compositions employing silicon-bridged metallocene compounds with bulky substituents. Methods for making these silicon-bridged metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins also are provided.08-22-2013
20100125124Methods of catalyst activation - A method comprising preparing a multi-component catalyst system comprising a catalyst and a cocatalyst, and adjusting the level of at least one component of the catalyst system to maintain a user-desired level of catalyst activity throughout a process, wherein the component comprises a catalyst activator and wherein the catalyst activator comprises the catalyst or the cocatalyst. A method comprising contacting a polymerization catalyst system comprising a Ziegler-Natta catalyst and a cocatalyst with a catalyst activator at least twice during a polymerization process, wherein the polymerization process is carried out in a reactor system comprising multiple reactor types.05-20-2010
20110028663STIRRED-TANK REACTOR AND METHOD FOR CARRYING OUT A POLYMERISATION REACTION USING SAID TYPE OF STIRRED-TANK REACTOR - The invention relates to a stirred-tank reactor and to a method for carrying out a polymerisation reaction of unsaturated monomers using a stirred-tank reactor. According to the invention, said stirred-tank reactor is characterised in that the product discharge point is designed as the central base outlet that is at least partially traversed by the agitator shaft. Said polymerisation is performed continuously under positive pressure, so that the stirred-tank reactor is operated hydrodynamically.02-03-2011
20120245308PROCESS FOR PREPARING POLYAMIDES - The present invention relates to a process for preparing a polyamide based on dicarboxylic acids and diamines, comprising the following stages: 09-27-2012
20090105428ANTISTATIC FOR OLEFIN POLYMERIZATION AND PROCESS FOR PREPARING IT - Process for preparing an antistatic for olefin polymerization by contacting an antistatically acting compound comprising at least one hydrogen atom bound to a nonmetallic heteroatom with at least one metal alkyl in an amount which is sufficient to react completely with the at least one hydrogen atom bound to a heteroatom, wherein the antistatically acting compound and the metal alkyl are each present in a concentration of at least 0.01% by weight during contacting.04-23-2009
20090036616Slurry loop reactors - An apparatus defined as a set of loop reactors suitable for the polymerization process of a monomer, preferably ethylene and optionally an olefin comonomer, comprising for each of said reactors: a plurality of interconnected pipes P defining a flow path for a polymer slurry, said slurry consisting essentially of ethylene, optionally a comonomer, a polymerization catalyst, liquid diluent and solid olefin polymer particles, means for feeding monomer, optionally a co-monomer, diluent and optionally hydrogen in the reactor, means for feeding a polymerization catalyst in the reactor, a pump suitable for maintaining the polymer slurry in circulation in such reactor, one or more settling legs connected to the pipes P of such reactor for settling of polymer slurry, one or more control valves connected to the outlet of such settling legs, and one or more flash lines for discharging settled polymer slurry out of the reactor characterized in that each of said loop reactors comprises a three-or-more-way valve defining three-or-more ends, one end A being positioned at the outlet of said one or more control valves. A method to switch from series to parallel configuration a set of loop reactors. The use of the apparatus to switch polymerization reactors from parallel to series configuration and vice-versa.02-05-2009
20130144016MODIFIED CATALYST SUPPORTS - A process for preparing a supported catalyst system comprising the following steps: 06-06-2013
20100331501USE OF HYDROGEN SCAVENGING CATALYSTS TO CONTROL POLYMER MOLECULAR WEIGHT AND HYDROGEN LEVELS IN A POLYMERIZATION REACTOR - The present invention provides dual catalyst systems containing a metallocene catalyst and a hydrogen scavenging catalyst, and polymerization processes employing these dual catalyst systems. Due to a reduction in hydrogen levels in the polymerization processes, olefin polymers produced from these polymerization processes may have a higher molecular weight, a lower melt index, and higher levels of unsaturation.12-30-2010
20100190934METHOD FOR PRODUCING POLYAMIDES - The process for preparing a polyamide based on dicarboxylic acids and diamines has the following stages: 07-29-2010
20110034644POLYESTER PROCESS USING A PIPE REACTOR - The invention is directed to polyester processes that utilizes a pipe reactor in the esterification, polycondensation, or both esterification and polycondensation processes. Pipe reactor processes of the present invention have a multitude of advantages over prior art processes including improved heat transfer, volume control, agitation and disengagement functions.02-10-2011
20110040049TUBULAR FLOW REACTOR AND METHOD OF MANUFACTURING POLYMERIC RESIN FINE PARTICLE - In the present invention, a tubular flow reactor can maintain a plug flow property even though the tubular flow reactor is downsized, and provided is the tubular flow reactor with which uniform resin fine particles exhibiting a narrow particle size distribution and a narrow molecular weight distribution can be prepared when the tubular flow reactor is used for preparation of the resin fine particle via emulsion polymerization or the like. Disclosed is a tubular flow reactor possessing a stirring blade and a cylindrical channel, wherein a ratio d/D is 0.3-0.9 when a diameter of the stirring blade is represented by d and an inner diameter of the cylindrical channel is represented by D, and a ratio Lb/La is 0.80-0.99 when a length of the stirring blade is represented by Lb and a length of the cylindrical channel is represented by La.02-17-2011
20110118424METHOD FOR PRODUCING THERMOPLASTIC COPOLYME - A thermoplastic copolymer having an excellent balance among properties such as coating resistance, color stability and fluidity and having high operability and productivity can be obtained by a method for producing a thermoplastic copolymer, comprising step (I) of supplying a monomer mixture (a) containing an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) to a complete mixing type reactor continuously to produce a copolymer (A) and step (II) of supplying the copolymer (A) continuously to a tubular reactor with a static mixing structure therein, which is placed in series with the complete mixing type reactor, and reacting the copolymer (A) to produce a copolymer (B).05-19-2011
20110124828Loop Reactor Suitable for Olefin Polymerization with Improved Product Removal Means - The present invention relates to a loop reactor suitable for olefin polymerization process comprising: 05-26-2011
20110245435PROCESS FOR CONTINUOUSLY PREPARING COPOLYAMIDES FROM LACTAMS AND SALTS OF DIAMINES AND DICARBOXYLIC ACIDS - A process for continuously preparing copolyamides from lactams and salts of diamines and dicarboxylic acids, in which lactams together with salts of diamines and dicarboxylic acids are passed from the top downward through a vertical polymerization tube at polyamide-forming temperatures, which comprises 10-06-2011
20110124827Oligomerisation of Olefins - In the oligomerisation of olefins in a tubular reactor employing a molecular sieve catalyst, the temperature of the reaction is monitored and the space velocity of the olefin feed to the reactor is reduced as the temperature increases. This has been found to increase catalyst life and lead to extended production runs. Further extensions of the production run are achieved by improving reactor operating stability as the end of the production run approaches.05-26-2011
20090048407RECIRCULATION LOOP REACTOR BULK POLYMERIZATION PROCESS - A process for producing polymer and more particularly adhesive using a recirculating loop reactor. In one embodiment the reactor includes one or more mixers to mix feed stock with the polymerized material recirculating in the reactor. In another embodiment a planetary roller extruder (PRE) may be used for this purpose. In still another embodiment, a combination of one or more static mixers and one or more PREs may be used.02-19-2009
20100056733METHOD OF RAPIDLY DETERMINING THE MFR IN THE HIGH-PRESSURE POLYMERIZATION ETHYLENE - Method of determining the melt mass flow rate of an ethylene polymer in the polymerization of ethylene or of ethylene with further comonomers, which is carried out at temperatures of from 140° C. to 350° C. and pressures of from 40 MPa to 350 MPa in a reactor to form the ethylene polymer and the ethylene polymer is subsequently cooled in a heat exchanger, which comprises: a) establishment of a correlation between the thermal conductivity of the ethylene polymer in the heat exchanger and the melt mass flow rate of the ethylene polymer, with the individual measurements each being carried out at an essentially constant melt mass flow rate, b) measurement of the thermal conductivity of an ethylene polymer in the heat exchanger c) calculation of the melt mass flow rate from the thermal conductivity measured in b) and the correlation established in a).03-04-2010
20120245307PROCESS FOR THE PREPARATION OF A PARTICULATE BIMODAL POLYETHYLENE PRODUCT - The invention relates to a process for the preparation of a particulate bimodal polyethylene product having a median particle diameter of less than 300 μm in a serially connected double loop reactor, wherein said polymerization catalyst applied in the polymerization process comprises a particulate metallocene-alumoxane catalyst immobilized on a porous silica support, wherein said polymerization catalyst has a median particle diameter of less than 50 μm; and whereby the ratio of the median particle diameter of the obtained bimodal polyethylene product to the median particle diameter of the applied polymerization catalyst is less than 30.09-27-2012
20100048837System and method for reducing fouling in a reactor - The techniques disclosed provide a treatment method for passivating the interior surface of a polymerization reactor to minimize the formation of a polymer coating on the surface. The passivation is performed using a passivating agent that reacts with adsorbed water to form labile passivation products. Both the passivating agent and passivation products may be easily removed from the reactor prior to polymerization. Other embodiments provide a reactor system with a tank configured to automatically add a passivating agent to the reactor and processes for making polymers using a treated reactor.02-25-2010
20100069581SPOUTED BED DEVICE, POLYOLEFIN PRODUCTION SYSTEM WITH SPOUTED BED DEVICE, AND POLYOLEFIN PRODUCTION PROCESS - A spouted bed device according to the present invention includes a vertically extending cylinder; a decreasing diameter member which is formed on the cylinder, has an inside diameter that decreases progressively downward, and has a gas inlet orifice at a bottom end thereof; and a tubular portion which extends downward from an edge of the gas inlet orifice. A spouted bed is formed in a treatment zone enclosed by a top surface of the decreasing diameter member and an inner wall of the cylinder above the decreasing diameter member.03-18-2010
20100069582POLYMERIZATION CATALYSTS FOR PRODUCING HIGH MOLECULAR WEIGHT POLYMERS WITH LOW LEVELS OF LONG CHAIN BRANCHING - This invention relates to catalyst compositions, methods, and polymers encompassing at least one Group 4 metallocene compound comprising bridging η03-18-2010
20100056732System and Method for Measuring Pressure and Flow in a Loop Reactor - A system and method for measuring pressure and flow rate of polymer slurry circulating in a loop reactor. For flow rate measurement, the loop reactor has a pressure tap on an outside radius of an elbow of the loop and a pressure tap on an inside radius of the elbow. The pressure taps incorporate diaphragms. Sensing legs couple the pressure taps with a differential pressure meter configured to provide a signal indicative of the flow rate of the polymer slurry. For pressure measurement, pressure taps without diaphragms at the loop reactor wall may be disposed at various points along the loop reactor, the pressure taps coupled to pressure sensing lines. A diluent flush line having a screen disposed therein may provide diluent to the pressure taps. The screen may reduce fouling of the pressure tap and sensing line with solids from the reactor.03-04-2010
20110098421Process for Improving the Devolatilization of Polymer Slurry Produced in a Polymerization Reactor - The present invention relates to a process for improving the devolatilization of polymer slurry produced in an olefin polymerization reactor. The process is characterized in that it involves an adjustment of the temperature of the interior surface of the flash line for periodically transferring polymer slurry from the polymerization reactor to a downstream processing unit. In particular, in accordance with the present process, the temperature of the interior surface of the flash line is adjusted to a temperature which is equal to or higher than the softening temperature of the polymer passing through said flash line whereby said temperature is higher in a first half of the length of the flash line than in the remaining length of the flash line.04-28-2011
20100069580CATALYST COMPOSITION FOR THE (CO) POLYMERIZATION OF PROPYLENE - The present invention relates to a process for the production of propylene polymers in the presence of a blend of a first Ziegler-Natta catalyst, which comprises a titanium compound having at least one titanium-halogen bond and a diether compound as internal electron donor, and a second Ziegler-Natta catalyst, which comprises a titanium compound having at least one titanium-halogen bond and a succinate compound as internal electron donor.03-18-2010
20110251359Polyisobutylene production process with improved efficiencies and/or for forming products having improved characteristics and polyisobutylene products produced thereby - A process for production of polyisobutylene includes subjecting a reaction admixture comprising isobutylene, a diluent for the isobutylene, which may be isobutane, and a catalyst composition, that may include a BF10-13-2011
20100130704Methods and Systems for Controlling Polymer Particle Size - Techniques are provided for producing polymer particles of a size just slightly larger than the size of polymer fines. The technique may prevent or limit the occurrence of reactor fouls associated with large polymer particles. The technique also may provide a greater weight percentage of solids in the reactor. The desired polymer particle size may be achieved by employing a catalyst having particles of a size determined based on the expected catalyst productivity. In certain embodiments, the catalyst particle size may be determined based on the expected catalyst productivity, the polymer particle density, the catalyst particle density, and/or the polymer particle size.05-27-2010
20110152473PROCESS FOR THE INTRODUCTION OF A POLYMERISATION CATALYST INTO A GAS-PHASE FLUIDISED BED - The present invention relates to a process for polymerisation in a gas-phase fluidised bed, and in particular to a process for the introduction of a polymerisation catalyst in solid form into a gas-phase fluidised bed, which process comprises using an injection device having an inner tube of internal cross-sectional area of 10 to 100 mm06-23-2011
20100113714INTEGRATED STEAM HEATING IN POLYESTER PRODUCTION PROCESS - Processes for making polyesters in a polyester production facility are disclosed, that include the steps of: forming a reaction medium comprising at least one monomer that includes terephthalic acid (TPA) and/or an ester derivative of TPA; subjecting at least a portion of the reaction medium to one or more chemical reactions in the polyester production facility to thereby produce the polyester; heating at least a portion of the reaction medium via indirect heat exchange with high-pressure steam, wherein the heating causes at least a portion of the high-pressure steam to condense and thereby provide pressurized condensed water; flashing at least a portion of the pressurized condensed water to thereby produce lower-pressure steam; and heating one or more process fluid streams of the polyester production facility via indirect heat exchange with at least a portion of the lower-pressure steam, wherein the process fluid streams include any stream that is formed predominately of the reaction medium and/or the at least one monomer.05-06-2010
20080242809Process for the Preparation of an Ethylene Copolymer in a Tubular Reactor - The invention relates to a process for the preparation of a copolymer of ethylene and a monomer copolymerisable therewith.10-02-2008
20080242808Interconnected Loop Reactors - The present invention describes a reactor comprising two interconnected loops wherein the growing polymer flows continuously in circuit from the first loop to the second loop through a First pipe and back to the first loop through a second pipe. It also discloses process for polymerising olefins in two interconnected loop reactors.10-02-2008
20120277384PREPARATION OF POLYPROPYLENE IN THE PRESENCE OF A SINGLE-SITE CATALYST - Process for the preparation of a polypropylene, wherein propylene is polymerised optionally with a comonomer selected from the group consisting of ethylene, a C4-C20 α-olefin and mixtures thereof, in the presence of a catalyst system comprising solid catalyst particles, wherein the solid catalyst particles (a) comprise a transition metal compound of formula (I) L11-01-2012
20120302706REACTOR AND METHOD FOR CONTINUOUS POLYMERIZATION - The present invention relates to a reactor (11-29-2012
20110021724Optimisation of the Ethylene Polymerisation Process - A method for ethylene slurry polymerisations in a loop reactor in the presence of ethylene monomer, diluent and catalyst and optionally co-monomer and hydrogen, wherein the polymerisation temperature is maintained below the swelling temperature, characterised in that the swelling temperature is calculated as a function of co-monomer concentration and the number average molecular weight of the polyethylene end-product.01-27-2011
20120149854NANO-LINKED HETERONUCLEAR METALLOCENE CATALYST COMPOSITIONS AND THEIR POLYMER PRODUCTS - The present invention provides polymerization catalyst compositions employing novel heterodinuclear metallocene compounds. Methods for making these new dinuclear metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins are also provided.06-14-2012
20100305284POLYMERIZATION CATALYSTS FOR PRODUCING POLYMERS WITH HIGH COMONOMER INCORPORATION - The present techniques relate to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene compound comprising bridged η12-02-2010
20100305283MULTISTAGE PROCESSF FOR THE POLYMERIZATION OF OLEFINS - A process for the multistage polymerization of olefins in a sequence of an upstream slurry reactor and a downstream gas-phase reactor, the transfer of polymer from the upstream reactor to the downstream reactor comprising the following steps: 12-02-2010
20090326172CATALYST COMPOSITION FOR THE COPOLYMERIZATION OF PROPYLENE - The present invention relates to a process for the production of propylene polymers in the presence of a Ziegler-Natta catalyst comprising a titanium compound having at least one titanium-halogen bond, and a blend of a diether compound and a succinate compound as internal electron donor, all supported on a magnesium halide in active form, an organoaluminium compound and an optional external donor.12-31-2009
20110178254APPARATUS FOR MANUFACTURING POLYMER RESIN, POLYMERIZATION VESSEL, AND METHOD FOR MANUFACTURING POLYMER RESIN - An apparatus for manufacturing a polymer resin comprises a polymerization vessel, a bearing part, a protection part, a circulating cooling means, a raw material-injecting nozzle and a flow path-constituting part. The protection part forms a first flow path between the protection part and the side face of the agitation axis. The circulating cooling means includes a circulating inlet nozzle provided on a side face of the protruding part so as to be opposite to the protection part. The flow path-constituting part is provided between the bearing part and the protection part so as to cover the side face of the agitation axis, to fix the bearing part and the protection part. This flow path-constituting part forms a second flow path between the side face of the agitation axis and the flow path-constituting part and a third flow path for coupling the second flow path with the raw material-injecting nozzle. The first to third flow paths constitute a continuous flow path and an uppermost end of the first flow path is opened to the inside of the protruding part. The gap, part of the first flow path other than the uppermost end, the second flow path and the third flow path are isolated from the inside of the protruding part.07-21-2011
20110263800METHOD AND APPARATUS FOR MANUFACTURING POLYMER PARTICLE10-27-2011
20110190460POLYMERIZATION PROCESS FOR PRODUCING BIMODAL POLYMERS - Catalyst compositions comprising a first metallocene compound, a second metallocene compound, an activator-support, and an organoaluminum compound are provided. An improved method for preparing cyclopentadienyl complexes used to produce polyolefins is also provided.08-04-2011
20110190459Process to Kill a Catalyzed Olefin Polymerization - Process to kill a continuous catalyzed olefin liquid phase polymerization in which the catalyst is a Ziegler-Natta or a metallocene catalyst, wherein, a predetermined amount of killing agent is injected into the reactor during at least twice the cycle time of the reactor.08-04-2011
20100029866Regulation of a Process for Producing Water-Absorbing Polymer Particles in a Heated Gas Phase - In a process for producing water-absorbing polymeric particles which comprises generating droplets comprising monomers, polymerizing the monomers in a heated gas phase surrounding the droplets and flowing the gas through the polymerization reactor, the temperature of the gas leaving the polymerization reactor is closed-loop controlled.02-04-2010
20100016523Method for Making a Transition between Polymer Grades - The present invention relates to a method of transition between polymer grades in a polymerisation process comprising polymerising at least one monomer in at least a first reactor and a second reactor connected to each other in series, wherein the monomer feed in the first reactor is maintained essentially constant during the transition.01-21-2010
20100324231PROCESS FOR PRODUCTION OF THERMOPLASTIC COPOLYMER - Disclosed is a process for producing a thermoplastic copolymer, which comprises step of supplying a monomer mixture (a) to a loop reactor continuously to produce a copolymer (A), the monomer mixture (a) comprising an aromatic vinyl monomer (a1), a vinyl cyanide monomer (a2) and an N-substituted maleimide monomer (a3). The process enables the production of a thermoplastic copolymer which has an excellent balance among physical properties such as heat resistance, color and flow property, reduces the amount of bleeding that may cause mold staining during molding processing and has excellent handleability and productivity.12-23-2010
20120232230PROCESS FOR MAKING ETHYLENE HOMOPOLYMERS - A process for making an ethylene homopolymer in the presence of an oxide-supported chromium catalyst is disclosed. A small amount of an α-olefin contacted with the catalyst before polymerizing ethylene or introduced into an ethylene homopolymerization unexpectedly boosts process productivity. When used at part per million levels, the α-olefin improves productivity while maintaining desirable polymer properties. The invention is particularly valuable for making HDPE resins useful for blow molding applications.09-13-2012
20110306736Slurry Loop Reactors - An apparatus defined as a set of loop reactors suitable for the polymerization process of a monomer, preferably ethylene and optionally an olefin co-monomer, comprising for each of said reactors:12-15-2011
20090318637METHOD AND SYSTEM FOR DETERMINING CATALYST ACTIVITY - The present invention relates to a method for determining activity of a catalyst in a polymerisation process, said polymerisation process comprising the steps of feeding a catalyst and a diluent into a storage vessel, to form a concentrated settled catalyst, feeding said concentrated settled catalyst into a mixing vessel equipped with mixing means and feeding hydrocarbon diluent into said mixing vessel, to form a diluted catalyst slurry, feeding said diluted catalyst slurry into a polymerisation reactor via a volumetric pump, and feeding at least one monomer into said polymerisation reactor to form a polymer. The method is characterised in that density of the diluted catalyst slurry is measured between an outlet of the mixing vessel and the volumetric pump, the amount of catalyst fed into the polymerisation reactor is determined based on the measured density of the diluted catalyst slurry, and the amount of catalyst fed into the polymerisation reactor is compared to the amount of the polymer formed to determine the activity of the catalyst. The invention also relates to a system suitable for carrying out the method.12-24-2009
20080262171Slurry Phase Polymerisation Process - A process comprising polymerising an olefin monomer optionally together with an olefin comonomer in the presence of a polymerisation catalyst in a diluent in a loop reactor which comprises at least 2 horizontal sections and at least 2 vertical sections to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the Froude number in at least 20% of the length of the vertical sections of the reactor loop is less than 85% of the Froude number in at least 20% of the length of the horizontal sections of the loop is disclosed.10-23-2008
20120010374Multistage Process for the Polymerization of Ethylene - The present invention relates to a slurry process for preparing an ethylene polymer having a melt flow ratio F/P, according to ASTM 1238, of higher than 25, carried out in two or more stages of polymerization at temperatures in the range from 60 to 120° C., in which at least two of the said two or more polymerization stages are carried out under different concentration of a molecular weight regulator, said process being carried out in the presence of a catalyst system comprising the product obtained by contacting (A) a solid catalyst component comprising Ti, Mg, halogen, and having a porosity (P01-12-2012
20090163677Loop Type Reactor for Polymerization - A process which comprises polymerising an olefin monomer in at least one continuous tubular loop reactor of a multiple reactor system, optionally together with an olefin comonomer, in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and diluent, wherein the average internal diameter of at least 50% of the total length of the continuous tubular loop reactor is at least 700 mm.06-25-2009
20090137753PROCESS FOR POLYMERIZING OLEFINS IN THE PRESENCE OF AN OLEFIN POLYMERIZATION CATALYST - The present invention relates to a process for the preparation of multimodal ethylene homo- or copolymers in at least two stages, the process comprising preparation of a first ethylene homo- or copolymer fraction in a loop reactor in slurry phase, preparation of a second ethylene homo- or copolymer fraction in a gas phase reactor, by using a catalyst not containing an inorganic oxide support, and operating the gas phase reactor in such conditions that at least part of the gas is recycled, and that at least a part of the recycled gas is condensed and the (partially) condensed gas is re-introduced into the gas phase reactor.05-28-2009
20090018280HORIZONTAL TRAYED REACTOR - A horizontal trayed reactor operable to facilitate a chemical reaction in a reaction medium flowing therethrough. The reactor can include a plurality of vertically spaced trays disposed within the horizontally elongated vessel shell. The reaction medium can flow in generally opposite directions on vertically adjacent trays so that the reaction medium flows generally back-and-forth through the reactor.01-15-2009
20120157638POLYMERIZATION PROCESS WITH IMPROVED POLYMER HOMOGENEITY - The present invention relates to a process for the polymerization of an olefin monomer. In particular, the present invention relates to a process for the polymerization of an olefin monomer and one or more optional comonomers in presence of a polymerization catalyst and hydrogen, said process being characterized by an improved control of the hydrogen concentration in the polymerization reactor. In addition, the present invention provides for an improved hydrogen feeding system to a polymerization reactor. Furthermore, the present invention provides for a polymerization reactor comprising such an improved hydrogen feeding system.06-21-2012
20120309910METHOD FOR REPLACING INCOMPATIBLE ETHYLENE POLYMERIZATION CATALYSTS - The present invention relates to a method for optimizing the sequential use of at least two ethylene polymerization catalysts to an ethylene polymerization loop reactor, comprising: 12-06-2012
20090198024FORMALDEHYDE-FREE, CARBONYL- AND RING-HYDROGENATED KETONE-ALDEHYDE RESINS BASED ON ALKYL ARYL KETONES AND FORMALDEHYDE WHICH HAVE A LOW OH FUNCTIONALITY AND A PROCESS FOR PREPARING THEM - The invention relates to formaldehyde-free, carbonyl- and ring-hydrogenated ketone-aldehyde resins based on alkyl aryl ketones and formaldehyde and having a low OH-functionality, a low fraction of crystallisable compounds, low viscosity, very low colour number, and very high heat stability and light stability, and also to a process for preparing them.08-06-2009
20110105701Dynamic Pressure Control in Double Loop Reactor - The present invention discloses a slurry loop reactor comprising at least two loop reactors connected in series and wherein the line connecting the two loops is subject to a dynamic pressure difference.05-05-2011
20110184130POLYESTER PRODUCTION SYSTEM EMPLOYING HORIZONTALLY ELONGATED ESTERIFICATION VESSEL - A polyester production process employing an esterification system that utilizes a horizontally elongated esterification vessel as an esterification reactor and/or a vapor-liquid disengagement vessel.07-28-2011
20120130027CAPS AND CLOSURES - 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.05-24-2012
20120252990Polymerization Process to Make Low Density Polyethylene - 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 1.10-04-2012
20120252989METHOD FOR REPLACING COMPATIBLE ETHYLENE POLYMERIZATION CATALYSTS - The present invention relates to a method for optimizing the sequential feeding of at least two ethylene polymerization catalysts to an ethylene polymerization reactor, comprising: 10-04-2012
20100298507Polyisobutylene Production Process With Improved Efficiencies And/Or For Forming Products Having Improved Characteristics And Polyisobutylene Products Produced Thereby - A process for production of polyisobutylene includes subjecting a reaction admixture comprising isobutylene, a diluent for the isobutylene, which may be isobutane, and a catalyst composition, that may include a BF11-25-2010
20100010174HALF-METALLOCENE CATALYST COMPOSITIONS AND THEIR POLYMER PRODUCTS - The present invention provides polymerization catalyst compositions employing half-metallocene compounds with a heteroatom-containing ligand bound to the transition metal. Methods for making these hybrid metallocene compounds and for using such compounds in catalyst compositions for the polymerization and copolymerization of olefins are also provided.01-14-2010
20100087606HIGH PRESSURE LOW DENSITY POLYETHYLENE RESINS WITH IMPROVED OPTICAL PROPERTIES PRODUCED THROUGH USE OF HIGHLY ACTIVE CHAIN TRANSFER AGENTS - Disclosed is an ethylene-based polymer with a density from about 0.90 to about 0.94 in grams per cubic centimeter, with a molecular weight distribution (M04-08-2010
20120220738HIGH PRESSURE LDPE FOR MEDICAL APPLICATIONS - A novel LDPE from radical, high pressure polymerization is devised.08-30-2012
20120252988PROCESS FOR PREPARING A BIMODAL POLYETHYLENE PRODUCT IN A SINGLE LOOP REACTOR - The present invention relates to a process for preparing a bimodal polyethylene product in a single loop reactor, comprising polymerizing ethylene monomer and optionally one or more olefin co-monomers in the presence of a single heterogeneous polymerization catalyst consisting of a metallocene-alumoxane catalyst immobilized on a porous support wherein said metallocene comprises only one transition metal. Said polymerization catalyst consists of two physically different fractions of support particles onto which said metallocene-alumoxane catalyst is immobilized.10-04-2012
20120190804DUAL METALLOCENE CATALYSTS FOR POLYMERIZATION OF BIMODAL POLYMERS - This invention relates to catalyst compositions, methods, and polymers encompassing at least one first Group 4 metallocene compound comprising bridging η07-26-2012
20090018285Method for Thermally Treating Polyester Pellets to Obtain a Partial Crystallization - The invention relates to a method for thermally treating polyester pellets to obtain a partial crystallization, whereby the polyester melt is delivered to an underwater granulating system and granulated; the thus obtained granulates are carried from the underwater granulating system through a water-solids separator over a short conveying distance; the dried granulates are then delivered to a treatment device at a granulate temperature higher than 100 degrees C. without external energy or heat being supplied. The heat treatment leading to partial crystallization results from the intrinsic heat of the granulates, whereby the treatment device is embodied as an at least lightly inclined reactor, into which the granulates are delivered at a temperature higher than 100 degrees C., the granulates passing through said reactor from the loading point to the discharge point under their own weight and leaving the same at a temperature higher than 130 degrees C.01-15-2009
20090018283MULTI-LEVEL TUBULAR REACTOR WITH DUAL HEADERS - A multi-level tubular reactor operable to facilitate a chemical reaction in a reaction medium flowing therethrough. The tubular reactor can include a plurality of horizontally elongated and vertically spaced tubular members coupled to and extending between a pair of horizontally spaced and vertically elongated headers.01-15-2009
20090018282MULTI-LEVEL TUBULAR REACTOR WITH OPPOSITELY EXTENDING SEGMENTS - A multi-level tubular reactor operable to facilitate a chemical reaction in a reaction medium flowing therethrough. The tubular reactor can include a plurality of horizontally elongated and vertically spaced reactor segments coupled to and extending outwardly from a common header. One or more of the reactor segments can contain a tray that divides the internal volume of the reactor segment into upper and lower chambers. The reaction medium can flow away from the header in the upper chambers and back to the header in the lower chambers.01-15-2009
20090018281MULTI-LEVEL TUBULAR REACTOR WITH INTERNAL TRAY - A multi-level tubular reactor operable to facilitate a chemical reaction in a reaction medium flowing therethrough. The tubular reactor can include a horizontally elongated reactor segment containing a tray that divides the internal volume of the reactor segment into upper and lower chambers. The reaction medium can flow through the upper and lower in generally opposite directions.01-15-2009
20120232229CATALYST SYSTEMS CONTAINING A BRIDGED METALLOCENE - The present invention provides polymerization processes utilizing a catalyst system containing an ansa-metallocene and a second metallocene compound for the production of olefin polymers.09-13-2012
20120264892METHOD FOR IMPROVING ETHYLENE POLYMERIZATION REACTION - The present invention relates to a method for initiating an ethylene polymerization reaction in an ethylene polymerization loop reactor. More particularly, the invention relates to the timing upon which hydrogen is introduced into the ethylene polymerization loop reactor. The catalysts used in the ethylene polymerization reaction according to present invention are preferably metallocene catalysts.10-18-2012
20110046322Clog-Resistant Pump Assembly For Slurry Loop Reactor - The pump assembly includes an impeller rotatably mounted in a pipe of the reactor having blades that generate a flow of fluid slurry through the pipe, a nosecone protruding in an upstream direction in front of the impeller blades that rotates along with the blades, and a plurality of stationary guide vanes connected to the housing upstream of the impeller blades and having free ends that are radially spaced apart from the nosecone. The leading edges of the stationary vanes are shaped to direct any stringy material into the radial gaps between the free ends of the stationary vanes and the rotating nose cone to be shredded and thus prevent fouling and clogging of the pump assembly when such stringy material is generated during the polymerization process.02-24-2011
20120271012METHOD FOR NEUTRALIZING POLYMERIZATION CATALYST - The present invention relates to a process for cleaning a catalyst slurry preparation system and/or a catalyst preparation system. More particularly, the invention relates to a cleaning process for a catalyst preparation system and/or for a catalyst slurry preparation system, wherein an aqueous catalyst inactivation agent is used to rinse the systems, or any parts thereof. The catalysts used in the present invention may be chromium, Ziegler-Natta or metallocene catalysts.10-25-2012
20120271011PROCESS FOR THE PREPARATION OF A PARTICULATE POLYETHYLENE PRODUCT - The invention relates to a process for the preparation of a particulate polyethylene product in a loop reactor, wherein the polymerization catalyst applied in the polymerization process comprises a particulate metallocene-alumoxane catalyst immobilized on a porous silica support; and whereby said metallocene-alumoxane catalyst is heterogeneously distributed on said porous silica support.10-25-2012
20120289665NOVEL POLYMERS - Copolymers of ethylene and α-olefins are provided having (a) a density (D) in the range 0.900-0.940 g/cm3, (b) a melt index MI11-15-2012
20120149855Nano-Linked Metallocene Catalyst Compositions and Their Polymer Products - The present invention provides polymerization catalyst compositions employing novel dinuclear metallocene compounds. Methods for making these new dinuclear metallocene compounds and for using such compounds in catalyst compositions for the polymerization and copolymerization of olefins are also provided.06-14-2012
20080255323Low Gel Chromium Catalysis - The present invention discloses the use of a chromium-based catalyst system in two serially connected loop reactors for copolymerising ethylene and a comonomer, at reduced productivity, the final polyethylene having a reduced amount of gel.10-16-2008
20130172497CATALYST COMPOSITIONS FOR THE POLYMERIZATION OF OLEFINS - Catalyst compositions containing N,N-bis[2-hydroxidebenzyl]amine transition metal compounds are disclosed. Methods for making these transition metal compounds and for using such compounds in catalyst compositions for the polymerization of olefins also are provided.07-04-2013
20080249261Method of preparing polymethylene-polyphenyl-polyamine - The present invention provides a method of preparing polymethylene-polyphenyl-polyamine (briefly referred to as polyamine, DAM), in which a high gravity rotating bed is used as the mixing reactor of formaldehyde and aniline hydrochloride, the mixing solution of aniline hydrochloride and circulation solution and the formaldehyde are fed into the high gravity rotating bed reactor proportionally to carry out mixing and condensation reaction under a condition of a very high gravity; the materials leaving the high gravity rotating bed reactor is introduced into a stirred vessel to proceed with the pre-condensation reaction and obtain a condensation solution; and the process steps of heating, molecular rearrangement, neutralization, water washing and purification, etc. are completed to obtain the refined DAM. With the method according to the present invention, the main by-products is obviously reduced in the condensation process, the phenomenon of deposit attaching to the inner walls of circulation pipes and heat exchanger and blockage are prevented in the condensation process, the impurity content is low in the refined DAM, and the subsequent product MDI has a lighter color, the product quality is stable and may be improved to a certain extent.10-09-2008
20080234443Process for fluid phase in-line blending of polymers - A process for fluid phase in-line blending of polymers. The process includes providing two or more reactor trains configured in parallel and a separator for product blending and product-feed separation; contacting in at least one of the parallel reactor trains olefin monomers having three or more carbon atoms, catalyst systems, optional comonomers, optional scavengers, and optional inert diluents or inert solvents, at a temperature above the solid-fluid phase transition temperature of the polymerization system and a pressure no lower than 10 MPa below the cloud point pressure of the polymerization system and less than 1500 MPa; forming a reactor effluent including a homogeneous fluid phase polymer-monomer mixture in each parallel reactor train; combining the reactor effluent from each parallel reactor; passing the combined reactor effluent through the separator; maintaining the temperature and pressure within the separator above the solid-fluid phase transition point but below the cloud point pressure and temperature to form a fluid-fluid two-phase system including a polymer-rich blend phase and a monomer-rich phase; and separating the monomer-rich phase from the polymer-rich blend phase. The separated monomer-rich phase is recycled to the polymerization reactor bank. The polymer-rich blend phase is conveyed to a downstream finishing stage for further monomer stripping, drying and/or pelletizing to form a polymer product blend.09-25-2008
20080227931Polyester process using a pipe reactor - The invention is directed to polyester processes that utilizes a pipe reactor in the esterification, polycondensation, or both esterification and polycondensation processes. Pipe reactor processes of the present invention have a multitude of advantages over prior art processes including improved heat transfer, volume control, agitation and disengagement functions.09-18-2008
20080221283Loop Reactor for Emulsion Polymerisation - Method of emulsion polymerisation wherein a reactor comprising a closed reactor loop is continuously charged with fresh monomers and water phase at substantially the same rate as the rate of an overflow of reactor charge discharged into a secondary line section. The reactor charge is continuously recirculated within the reactor loop. The discharge rate and the circulation rate in the loop are balanced such as to result in a monomer content in the loop of less than 12 wt. %. The secondary line section has a volume of less than twice the volume of the reactor loop.09-11-2008
20080221282Polymerization Process - The invention relates to a process for continuously preparing water-absorbing polymer particles by mixing a monomer solution with a redox initiator consisting of at least one oxidizing agent and at least one reducing agent and polymerizing it, wherein the monomer solution is mixed with at least one oxidizing agent upstream of the polymerization reactor and the at least one reducing agent is metered into the polymerization reactor, and also to an apparatus for performing the process.09-11-2008
20080221280Catalyst deployment in bimodal polyolefin production - Provided is a method for polymerising olefins in a double loop reactor, which method comprises the addition of fresh catalyst system into both the first and the second loop reactors thereby retrieving in a single stream, a final product consisting of two polymer components.09-11-2008
20130102742PUMPING APPARATUS AND PROCESS FOR POLYMERIZATION IN LOOP REACTORS - An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.04-25-2013
20130102741PROCESS FOR IMPROVING THE DEVOLATILIZATION OF POLYMER SLURRY PRODUCED IN A POLYMERIZATION REACTOR - The present invention relates to a process for improving the devolatilization of polymer slurry produced in an olefin polymerization reactor. The process is characterized in that it involves an adjustment of the temperature of the interior surface of the flash line for periodically transferring polymer slurry from the polymerization reactor to a downstream processing unit. In particular, in accordance with the present process, the temperature of the interior surface of the flash line is adjusted to a temperature which is equal to or higher than the softening temperature of the polymer passing through said flash line whereby said temperature is higher in a first half of the length of the flash line than in the remaining length of the flash line.04-25-2013
20130131288METHOD FOR PRODUCING POLYETHYLENE - The present invention relates to a method for consecutively producing at least two different polyethylene resins in one slurry loop reactor, comprising producing a first polyethylene resin in the presence of a Ziegler-Natta and/or a Chromium catalyst, and consecutively producing a second polyethylene resin in the presence of a metallocene catalyst, characterized in that the ratio of the melt flow index of the first produced polyethylene resin to the melt flow index of the second produced polyethylene resin is at least 0.3.05-23-2013
20130131287Process for preparing polyolefins - The present invention relates to a process of preparing a polyolefin in a loop reactor by introducing anti-fouling agent in by-pass pipes. Also, the invention relates to the use of anti-fouling agent to prevent blockage by feeding the anti-fouling agent into the by-pass pipes of the loop reactor.05-23-2013
20110275771LOOP REACTOR DESIGN - Loop reactors are described herein. The loop reactors generally include a lower horizontal segment, an upper horizontal segment and a vertical segment in operable communication and an in-line pump incorporated within the loop reactor.11-10-2011
20110275770High Pressure Polymerization Process - The invention relates to high pressure tubular reactor olefin polymerization plants having improved specific energy consumption. The plants may be newly constructed or made by de-bottlenecking an existing plant. The tube of the tubular reactor may have improved arrangements for cooling to increase conversion and optimized polymer-recycle gas separation arrangements using a jet pump for recycling unreacted monomer while permitting haze to be maintained. The improved cooling arrangements include a reduced pressure cooling zone forming the tail end of the tube and/or a shortened heating zone for the front feed and allowing more monomer to be fed as a side feed.11-10-2011
20110257348CATALYST COMPOSITIONS FOR PRODUCING HIGH Mz/Mw POLYOLEFINS - The present invention provides a polymerization process utilizing a dual ansa-metallocene catalyst system. Polymers produced from the polymerization process are also provided, and these polymers have a reverse comonomer distribution, a non-bimodal molecular weight distribution, a ratio of Mw/Mn from about 3 to about 8, and a ratio of Mz/Mw from about 3 to about 6.10-20-2011
20130184419Ethylene-Based Interpolymers and Processes to Make the Same - Ethylene-based interpolymers, e.g., ethylene-acrylic acid copolymers, are made by a process comprising the steps of: A. Injecting a first feed comprising a chain transfer agent system (CTA system) and ethylene into a first autoclave reactor zone 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 (2) at least one of transferring or freshly injecting a feed comprising a CTA system into the second reactor zone to produce a second zone reaction product, the CTA system of the second reactor zone having a transfer activity of Z2; and with the proviso that the ratio of Z1:Z2 is greater than 1. The comonomer comprises at least one carboxylic acid group or an anhydride group.07-18-2013
20130123441Process for preparing polyolefins - The present invention relates to a process of preparing a polyolefin in a loop reactor by introducing anti-fouling agent through a sleeve provided around at least part of the shaft of the pump. Also, the invention relates to the use of anti-fouling agent to prevent or reduce fouling by feeding the anti-fouling agent against the impeller of the pump upon introduction to the loop reactor.05-16-2013
20130190462PROCESS FOR PREPARING POLYETHER CARBONATE POLYOLS WITH DOUBLE METAL CYANIDE CATALYSTS AND IN THE PRESENCE OF METAL SALTS - The present invention relates to a process for the preparation of polyether carbonate polyols by catalytic copolymerisation of carbon dioxide (CO07-25-2013
20130197168Polymerization Process to Make Low Density Polyethylene - A high pressure polymerization process to form an ethylene-based polymer comprises the steps of: A. Injecting a first feed comprising a chain transfer agent system (CTA system) and ethylene 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 at least one of the first reactor zone product and the freshly injected feed comprises a CTA system with a transfer activity of Z2; and with the proviso that the ratio of Z1:Z2 is greater than 1.08-01-2013
20090318638Slurry Polymerisation Process of Ethylene in the Presence of Low Amount of Scavenger - The invention discloses a metallocene catalysed slurry polymerisation process s of ethylene in the presence of a low concentration of scavenger. This allows improving the anti-sheeting of the reactor during the polymerisation process.12-24-2009
20130211018MODIFIED CATALYST SUPPORTS - The invention covers a supported catalyst system prepared according to a process comprising the following step: 08-15-2013

Patent applications in class POLYMERIZING IN TUBULAR OR LOOP REACTOR