Abstract: A method for removing contaminants from a process stream that includes the use of reticulated material to filter the process stream in a vessel located upstream of a process unit. The reticulated material can be used with other conventional filter media within the vessel.

Abstract: This invention relates to a process to polymerize olefins comprising contacting, at a temperature of 60° C.

Abstract: A process comprising polymerizing in a loop reactor an olefin monomer optionally together with an olefin comonomer in the presence of a polymerization catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the Froude number is maintained at or below 20 is disclosed.

Abstract: A process comprising polymerising in a loop reactor of 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 internal diameter of at least 50% of the total length of the reactor is at least 700 millimeters and the solids concentration in the reactor is at least 20 volume % is disclosed.

Abstract: The present invention relates to an improved method for preparing an ethylene-silane copolymer comprising hydrolysable silane groups by radical-initiated polymerisation of ethylene and an olefinically unsaturated silane compound, such as vinyl trimethoxysilane (VTMS). Said method is performed in a multi-zone reactor comprising two or more reaction zones, wherein advantageously essentially all of the silane compound is introduced into the first reaction zone to provide a higher conversion of silane monomer into polymer.

Abstract: The present invention relates to an ethylene homo or copolymer characterized as having long chain branching, and having a molecular weight distribution, Mw/Mn, and a GPC-LALLS CDF, which satisfies the following relationship: y?0.0663x-0.015, wherein y=GPC-LALLS CDF and x=Mw/Mn measured by conventional GPC, a line drawn from where the LS chromatogram intersects with molecular weight 350,000 and molecular weight 1,150,000 has a positive slope, preferably with a melt index between 0.15 and 2000 g/10 minutes and having long chain branching. In addition, the invention relates to a free radical initiation polymerization process for the preparation of ethylene polymers or copolymers, comprising reacting ethylene and optionally one or more comonomers at a high pressure, conveniently between 13,000 psig and 100,000 psig, and at reactor temperatures of 115° C. to 400° C., preferably 125-400° C., more preferably 140-350° C., especially 165-320° C.

Abstract: The use of a multimodal polyethylene composition comprising as comonomers to ethylene at least two C4-12 alpha olefins in injection molding.

Abstract: Process for polymerizing at least one olefinic monomer selected from ethylene, propylene and 1-butene in a loop reactor in the presence of a polymerization catalyst at from 20 to 150° C., but below the melting point of a polymer to be formed, and a pressure of from 43 to 80 bar, where the polymer formed is present in a suspension in a liquid or supercritical suspension medium and wherein the suspension is circulated by means of an axial pump, wherein the polymerization is carried out at an average solids concentration in the reactor of more than 53% by weight, in the case of continuous product discharge, and at an average solids concentration in the reactor of more than 45% by weight, in the case of discontinuous product discharge, and wherein the polymerization is carried out at an ethylene concentration of at least 10 mol %, based on the suspension medium.

Abstract: The present invention concerns a high melt strength propylene polymer or copolymer suitable for manufacturing foams and thermoformed product exhibiting a melt strength of at least 3 g and comprising a high molar mass portion and a low or medium molar mass portion. The polymers are produced by subjecting propylene and optionally other olefins to polymerization in a plurality of polymerization reactors connected in series, employing different amounts of hydrogen as a molar mass modifier in at least two of the reactors, and carrying out the polymerization reaction in the presence of a catalyst system capable of catalyzing the formation of a high molar mass polymerization product having a MFR2 of less than 0.1 g/10 min and a low or medium molar mass polymerization product having a MFR2 of more than 0.5 g/10 min.

Abstract: This invention relates to a process to polymerize olefins comprising contacting, in a polymerization system, olefins having three or more carbon atoms with a catalyst compound, activator, optionally comonomer, and optionally diluent or solvent, at a temperature above the cloud point temperature of the polymerization system and a pressure no lower than 10 MPa below the cloud point pressure of the polymerization system, where the polymerization system comprises any comonomer present, any diluent or solvent present, the polymer product, where the olefins having three or more carbon atoms are present at 40 weight % or more.

Abstract: This invention is directed to processes of making polymer in the presence of a hydrofluorocarbon or perfluorocarbon and recovering the polymer. The processes provided enable polymerization processes to be practiced with minimal fouling in the reaction system, and to the recovery of the hydrofluorocarbon and other hydrocarbons such as hydrocarbons for reuse in the process or hydrocarbon by-products from the polymerization process. The invention is particularly beneficial in the production of ethylene based polymers using bulky ligand metallocene-type catalyst systems.

Abstract: 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.

Abstract: Disclosed is a continuous process for the production of copolymers. The copolymers can be made with at least one (meth)acrylate monomer.

Abstract: 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.

Abstract: A process is provided for recovering polymer solids from a polymerisation reactor effluent. The process comprises extracting the polymerisation effluent from a Slurry polymerisation reactor; passing the effluent, or a part thereof, to a flash vessel for flashing liquid in the effluent to vapour, and removing said vapour from said flash vessel; passing the polymer solids from the flash vessel to a transfer apparatus which comprises a transfer vessel; passing the polymer solids from the transfer vessel to a purging means for removing residual liquid from the polymer solids; wherein the polymer solids are passed from the flash vessel to the purging means in a continuous flow such that a quantity of polymer solids is maintained in the transfer vessel. An apparatus for performing the process is also provided.

Abstract: Process and apparatus for continuously producing olefin polymers in a slurry phase reactor in a hydrocarbon diluent or liquid monomer. The process comprises continuously withdrawing from the slurry phase reactor a polymer slurry containing polymer and a fluid phase, which contains hydrocarbons and optionally hydrogen, and concentrating the slurry with a self-cleaning screen by removing a part of the fluid phase to provide a concentrated slurry. The openings of the screen, which can have a planar or cylindrical configuration, are smallest at the inflow surface of the screen and increases towards the outflow surface. By the present invention, the need for service and maintenance is significantly reduced.

Abstract: The present invention relates to an apparatus for preparing and supplying catalyst to an ethylene slurry loop polymerisation reactor and to an apparatus for controlling the injection of catalyst slurry in a polymerization reactor wherein polyethylene is prepared. The present invention a Iso relates to a method for optimising catalyst supply to a polymerisation reactor. The diluted catalyst is transferred to the reactor (1) using a membrane pump (5) controllable in function of the concentration of a reactant in said reactor (1).

Abstract: The present invention discloses a method for controlling the onset and development of swelling in a slurry loop reactor by progressively diluting the reactor, the amount of dilution being driven by the amplitude of the fluctuations measured on some plant measurement.

Abstract: The present invention provides a block copolymer of styrene and an unsaturated cyclic anhydride, such as maleic anhydride, a process for making a copolymer using controlled free radical polymerization in which certain parameters are adjusted to control the microstructure and molecular weight of the copolymer, and a method for using the block copolymer, including as a compatibilizer. Microstructure and molecular weight in the block copolymer can be controlled by adjusting the ratio of stable free radical to initiator. The copolymer can be made in a one step process and has a controlled microstructure that allows one block to be reactive toward several chemical moieties available in engineering polymers and the other block to be fully miscible with polystyrene or polymers miscible with polystyrene or polymers miscible with polystyrene such as polyphenylene ether.

Abstract: This invention relates to a process to produce propylene polymers comprising contacting a metallocene catalyst compound and an activator in a reaction medium comprising propylene, from 0 to 30 volume % of one or more solvents and from 0 to 30 mole % of one or more comonomers, under temperature and pressure conditions below the melting point of the propylene polymer and where: a) the temperature is at or above the critical temperature for the reaction medium, and the pressure is at least 500 kPa above the critical pressure of the reaction medium; or b) the temperature is 1° C. or more above the critical temperature for the reaction medium, and the pressure is at or above the critical pressure of the reaction medium; or c) the temperature is 1° C. or more above the critical temperature for the reaction medium, and the pressure is at least 500 kPa above the critical pressure of the reaction medium.

Abstract: A method of preventing or inhibiting fouling in an olefin polymerization fluidized-bed reactor is provided. The method involves varying the fluidization velocity inside the reactor over time about a set point.

Abstract: A method for polymerizing olefins in a fluidized-bed reactor is provided. The method involves introducing a fluid into the fluidized-bed reactor at an angle and amount sufficient to induce one or more swirls in the fluidized bed in the reactor.

Abstract: A propylene polymerisation process carried out in the presence of an anti-fouling agent; characterised in that the anti-fouling agent comprises an anti-fouling polymer containing: (1) one or more blocks —(CH2—CH2—O)k— where each k is in the range from 1 to 50; and (2) one or more blocks —(CH2—CH(R)—O)n— where R comprises an alkyl group having from 1 to 6 carbon atoms and each n is in the range from 1 to 50; and terminated by a R? and a R? end groups wherein R? is OH or an alkoxy having from 1 to 6 carbon atoms and R? is H or an alkyl having from 1 to 6 carbon atoms, and the anti-fouling polymer is solvated in a solvent comprising cyclohexane when added to the polymerisation medium.

Abstract: Production of vinyl polymers by the polymerization of vinyl monomers in a planetary gear extruder.

Abstract: The present invention relates to a process for improving the start up of polymerization or copolymerization of ethylene in a gas phase reactor, preferably a fluidised bed gas phase reactor.

Abstract: A process of converting a loop reactor into multiple loop reactors comprising starting with a loop reactor comprising at least 8 vertical legs, at least two non-vertical conversion runs, each non-vertical run connected in fluid flow communication with two vertical legs; at least two feed inlets; and at least two continuous discharge conduits; disconnecting at least one connection of each conversion run; and reconnecting each conversion run in fluid flow communication with a different vertical leg in such a manner to form multiple loop reactors each having at least one feed inlet and at least one continuous discharge conduit.

Abstract: A method for removing contaminants from an process stream that includes the use of reticulated material to filter the process stream. The reticulated material also facilitate process stream flow distribution in process units. The reticulated material can be packed with a void space between a substantial number of the reticulated material that can be varied to enhance filtration and flow distribution. The method of filtering also provides a method of removing contaminants leaving process equipment. The methods can be used on a variety of process streams and process equipment. The reticulated material can include ceramics, metallic materials, and chemical vapor deposition elements. The reticulated material can be of various shapes and sizes, and can also be catalytically active.

Abstract: The invention relates to new processes to produce polymers utilizing bayonette cooled slurry reactor systems and diluents including hydrofluorocarbons.

Abstract: 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.

Abstract: Polybutylene terephthalate having good heat stability and excellent hydrolysis resistance is continuously produced in a series of a first reactor for reacting an aromatic dicarboxylic acid comprising terephthalic acid as a main ingredient or a derivative thereof with a glycol comprising 1,4-butanediol as a main ingredient, thereby producing an oligomer with an average degree of polymerization of 2.2 to 5, a second reactor for polycondensating the oligomer from the first reactor, thereby preparing a low polymerization product with an average degree of polymerization of 25 to 40, and a third reactor for further polycondensating the low polymerization product from the second reactor, thereby producing a high molecular weight polyester with an average degree of polymerization of 70 to 130, or followed by a fourth reactor for further polycondensing the polyester from the third reactor to an average degree of polymerization of 150 to 200, thereby producing a high molecular weight polyester.

Abstract: There are disclosed polyester processes using a pipe reactor and corresponding apparatuses. In particular, there are disclosed processes and corresponding apparatuses including an esterification pipe reactor operated in an upflow or downflow mode, especially in a regime including stratified flow.

Abstract: Processes to polymerize or oligomerize olefins by contacting olefins with ?-diimine metal complexes. In particular, alpha olefins can be produced in high selectivity by contacting ethylene with selected ?-diimine metal complexes. In some cases an activator such as an alkylaluminum compound is also contacted with ethylene and the ?-diimine metal complexes.

Abstract: A process for polymerizing one or more alpha-olefins of formula CH2?CHT wherein T is a hydrogen atom or a C1–C20 alkyl radical comprising the following steps: a) contacting in a continuous way one or more of said alpha olefins with a metallocene based catalyst system in a loop reactor, wherein: (i) the reaction is carried out in a liquid medium; (ii) the average residence time of the metallocene-based catalyst system is not more than 30 minutes; (iii) the temperature of the loop ranges from 25° to 70° C.; in order to obtain a polymerization degree ranging from 60 to 500 g per gram of catalyst system; b) feeding in continuous the prepolymerized metallocene-based catalyst system obtained in step a) into a polymerization reactor C) polymerizing one or more alpha-olefins, the same or different from the alpha olefins used in step a), in the presence of said prepolymerized metallocene-based catalyst system.

Abstract: The present invention concerns a process and an apparatus for continuous polymerisation of olefin monomers in a cascade of polymerisation reactors. According to the process, an olefin monomer is polymerised first in slurry phase in an inert hydrocarbon diluent in at least one loop reactor and then, subsequently, in gas phase in at least one gas phase reactor. According to the invention, a polymer slurry is continuously withdrawn from the loop reactor and optionally concentrated. The concentrated slurry is conducted to a high pressure flash unit in order to remove the remaining fluid phase, and fed to the gas phase reactor. With the process described in this invention, it is possible to produce bimodal polyethylene with good properties. The operation of the process is stable because of the truly continuous operation.

Abstract: The invention provides a copolymer of ethylene and at least 5 mol % of comonomer units derived from an alkyl acrylate or alkyl methacrylate, wherein the copolymer has a melt index of from 1 to 10,000 g/10 min, and a maximum peak melting temperature of at least 100° C. The alkyl group of the alkyl acrylate or alkyl methacrylate can be a linear or branched C1 to C12 group, particularly n-butyl. The copolymer shows increased heat resistance as characterized by a temperature required to melt 50% of the copolymer of at least 80° C., a temperature required to melt 80% of the copolymer of at least 100° C., a temperature required to melt 100% of the copolymer of at least 110° C. The invention further provides a process for copolymerizing ethylene and an alkyl acrylate or alkyl methacrylate comonomer.

Abstract: A method for transferring polymer within a polymerization system, comprising continuously withdrawing the polymer from the reactor and conveying the polymer from a reactor to a flash chamber via a pressure differential between the reactor and the flash chamber. A method for transferring polymer within a polymerization system comprising conveying the polymer from a reactor to a flash chamber via a pressure differential between the reactor and the flash chamber and purging interstitial gases from the polymer prior to conveying the polymer from the flash chamber to a purge column. A method for transferring polymer within a polymerization system comprising conveying the polymer from a flash chamber directly to a purge column via a pressure differential between the flash chamber and the purge column.

Abstract: A method of continuous polymerization using differential radial stirring is provided. Particularly suited for this method is a stirred tube reactor with a plurality of collinear stirring shafts that may rotate independently.

Abstract: A recycling and recovery system and process comprising a flash gas separator that receives a slurry comprising liquid medium and solid polymer particles. The flash gas separator separates the diluent from the solid polymer particles as a vapor stream comprising at least diluent and heavies. A line receives the vapor stream from the flash gas separator. The line leads to a heavies removal system that yields a liquid that is relatively concentrated in heavies and a diluent vapor that is relatively free of heavies. The liquid is passed to a heavies column while the diluent vapor is passed to a diluent recycle chamber and then recycled to a slurry polymerization reactor without additional treatment to remove heavies.

Abstract: There are disclosed polyester processes using a pipe reactor and corresponding apparatuses. In particular, there are disclosed processes and corresponding apparatuses including an esterification pipe reactor with a recirculating reaction zone (RR zone) and a plug reaction profile reaction zone (PRPR zone), especially when operated with a significant part of the overall conversion taking place in the plug reaction profile reaction zone (PRPR zone).

Abstract: A method for continuously separating polymer from a high pressure fluid stream comprises subjecting the high pressure fluid stream comprising polymer particles to a filter, wherein the filter segregates the high pressure fluid stream from the polymer particles; subjecting the polymer particles to a rotating device which transports the polymer particles away from the filter, wherein the polymer particles are exposed to thermal conditions sufficient to melt the polymer particles and form a seal surrounding at least a portion of the rotating device; and separating the molten polymer from the rotating device. The method is carried out such that the separation of polymer from the high pressure fluid stream occurs under steady-state.

Abstract: A process for making a relatively low molecular weight, mid-range vinylidene content PIB polymer product comprising a liquid phase polymerization process conducted in a loop reactor at a temperature of at least 60° F. using a BF3/methanol catalyst complex and a contact time of no more than 4 minutes. At least about 90% of the PIB molecules present in the product comprise alpha or beta position isomers. The vinylidene (alpha) isomer content of the product may range from 20% to 70% thereof, and the content of tetra-substituted internal double bonds is very low, advantageously no more than about 10%, preferably less than about 5% and ideally less than about 1–2%.

Abstract: The tendency of copolymer fluff grains of propylene and ethylene to agglomerate is reduced by injecting at least one olefin comonomer, such as ethylene monomer, into more than one point along the length of the reactor, rather than injecting all of the ethylene at one point. This process reduces the tendency of copolymer fluff grains to agglomerate and cause processing problems as compared with injecting the comonomer at only one point. Copolymer made by this process is expected to have lower substantially amorphous polypropylene content and better organoleptics than copolymer made where the ethylene is injected at only one point. In one non-limiting embodiment the copolymerization reactor is a loop-type reactor.

Abstract: A polymerization loop reactor including a loop reaction zone, a continuous takeoff, and a fluid slurry disposed in the reaction zone. A generally cylindrical wall defines the loop reaction zone. The length of the loop reaction zone and the nominal outside diameter of the generally cylindrical wall define a length/diameter ratio greater than 250. The reactor can be charged with a fluid slurry including an olefin monomer reactant, solid olefin polymer particles, and a liquid diluent. The concentration of the solid olefin polymer particles in the slurry can be greater than 40 weight percent based on the weight of polymer particles and the weight of liquid diluent. Also disclosed is a polymerization process carried out by polymerizing, in the loop reaction zone of a reactor as defined above, at least one olefin monomer in a liquid diluent to produce a fluid slurry as defined above.

Abstract: A process for producing bimodal polyethylene resins in two reactors in series, the process comprising producing a first polyethylene resin fraction in a first slurry loop reactor in a diluent in the presence of a catalyst and producing a second polyethylene resin fraction in a second slurry loop reactor, serially connected to the first reactor, in the diluent in the presence of the catalyst, the first polyethylene resin fraction being passed from the first reactor to the second reactor together with the catalyst, one of the first and second reactors producing a resin fraction of higher molecular than the resin fraction produced by the other of the first and second reactors, characterised in that the first reactor is fed with a feed of ethylene and diluent having an ethylene content of at least 70 wt % based on the weight of the diluent and in that in the first reactor the slurry of polyethylene in the diluent has a solids content of at least 30 wt % based on the weight of the diluent.

Abstract: A process/apparatus is disclosed for continuously separating a liquid medium comprising diluent and unreacted monomers from a polymerization effluent comprising diluent, unreacted monomers and polymer solids, comprising a continuous discharge of the polymerization effluent from a slurry reactor through a discharge valve and transfer conduit into a first intermediate pressure flash tank with a conical bottom defined by substantially straight sides inclined at an angle to that of horizontal equal to or greater than the angle of slide of the slurry/polymer solids and an exit seal chamber of such diameter (d) and length (l) as to maintain a desired volume of concentrated polymer solids/slurry in the exit seal chamber such as to form a pressure seal while continuously discharging a plug flow of concentrated polymer solids/slurry bottom product of said first flash tank from the exit seal chamber through a seal chamber exit reducer with inclined sides defined by substantially straight sides inclined at an angle to t

Abstract: 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.

Abstract: A slurry polymerization process removes a portion of the fluid slurry without using a settling leg or a continuous take-off. The process uses a reactor take-off valve that is periodically fully closed and fully opened such that the withdrawn slurry is removed from the reactor in a discontinuous manner. The regular, periodic full closing and full opening of the take-off valve reduces instances of polymer plugging the take-off valve. In another aspect of the invention, a take-off valve is throttled in a repetitive pattern to reduce plugging of the take-off valve.

Abstract: A process is provided that produces polyolefins. The process comprises mixing a first stream, which comprises at least one catalyst deactivating agent, with a second stream, which comprises at least one polyolefin, at least one catalyst, at least one diluent, and at least one monomer, to produce a third stream, which comprises at least one polyolefin, at least one deactivated catalyst, at least one diluent, and at least one monomer. By utilizing the deactivating agent, polymerization can be slowed, or substantially stopped, when downstream equipment is being repaired or process control problems are being corrected. Later, polymerization can be restarted without the use of scavengers to remove poisons from the slurry polymerization reactor, and polyolefin production can be resumed.

Abstract: A novel loop/slurry olefin polymerization process is provided which produces ultra-high molecular weight ethylene homopolymer.

Abstract: Apparatus for olefin polymerization includes one or more shell and tube olefin polymerization reactors, each of which has an olefin polymerization reaction mixture inlet connection and a crude polyolefin product outlet connection. Each reactor is equipped with a recirculation system including a pump arranged to circulate a reaction mixture through the tube side of the reactor independently of the introduction of olefin polymerization reaction mixture into the reactor. The apparatus may also include an inlet reaction mixture distribution manifold and an outlet polymerization reaction mixture collection manifold interconnecting the reactors for operation in parallel. The apparatus also includes catalyst composition and catalyst modifier inlets for each reactor arranged such that a catalyst modifier to may be introduced into each reactor at a rate which is independent of the introduction of catalyst composition.