Abstract: Process for the continuous preparation of ethylene copolymers by free-radical copolymerization of ethylene and at least one comonomer in a cascade comprising at least two reactors, wherein one or more initiators are fed into the reaction mixture downstream of the first reactor.

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: 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.

Abstract: 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.

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: 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: a) heating the slurry of polyolefin particles to evaporate the liquid polymerization medium; b) separating the polyolefin particles from the obtained gaseous phase in at least a separation chamber; c) transferring the polyolefin particles to said downstream reactor by means of a couple of lock hoppers working intermittently in parallel, where one of said lock hoppers is continuously filled with the polymer coming from said separation chamber, while simultaneously the other one is continuously pressurized by means of a gas comprising the reaction mixture coming from said downstream reactor.

Abstract: 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 (PF), measured by the mercury method and due to pores with radius equal to, or lower than, 1 ?m of at least 0.3 cm3/g and a surface area determined by BET method, of lower than 100 m2/g, and (B) of an organoaluminum compound.

Abstract: There are disclosed polymerization processes and associated apparatuses. The polymerization processes involve both making a polymeric material in a fluidized bed reactor having a feed distributor and catching a spitwad with a spitwad catcher, and the apparatuses are those corresponding to such processes.

Abstract: 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: a plurality of interconnected pipes P defining a flow path for a polymer slurry, said slurry consisting essentially of ethylene, optionally a co-monomer, 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

Abstract: 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: a) providing at least two different initiators as solution in a suitable solvent or in liquid state, b) mixing the initiators and optionally additional solvent in at least two static mixers and c) feeding each of the mixtures to a different initiator injection point of the high pressure reactor, and apparatus for feeding initiator mixtures to a high pressure reactor with at least two spatially separated initiator injection points.

Abstract: 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.

Abstract: 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.

Abstract: A device for degassing a flowable, viscous and pasty product includes a reactor having a product inlet and a product discharge outlet. A plurality of rotors each defining a reaction zone are located side-by-side in the reactor and a separate driving system mounted outside of the reactor for rotating each rotor with each driving system being an hydraulic system.

Abstract: A process for the polymerization of olefin's, including: introducing an olefin and a polymerization catalyst into a polymerization reactor to form a polyolefin, the polymerization reactor including: a fluidized bed region having a top and a bottom; and a motive bed region; wherein a first end of the motive bed region is fluidly connected to the top of the fluidized bed region; and wherein a second end of the motive bed region is fluidly connected to the bottom of the fluidized bed region; and wherein a diameter of the fluidized bed region is greater than a diameter of the motive bed region; circulating at least a portion of the olefin, the catalyst, and the polyolefin through the fluidized bed region and the motive bed region; maintaining a dense-phase fluidized bed within the fluidized bed region; recovering polyolefin from the fluidized bed region, is provided. A reactor system directed to the process is also provided.

Abstract: 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.

Abstract: There are disclosed polymerization processes and associated apparatuses. The polymerization processes involve both making a polymeric material in a fluidized bed reactor having a feed distributor and catching a spitwad with a spitwad catcher, and the apparatuses are those corresponding to such processes.

Abstract: Embodiments of our invention relate generally to methods of monitoring and controlling polymerization reactions including reactions producing multimodal polymer products using multiple catalysts in a single reactor. Embodiments of the invention provide methods of rapidly monitoring and controlling polymerization reactions without the need to sample and test the polymer properties. The method uses reactor control data and material inventory data in a mathematical leading indicator function to control the reactor conditions, and thereby the products produced under those conditions.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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, b) continuously removing pre-polymerised reaction mixture from the continuous mixing reactor and continuously providing pre-polymerised reaction mixture to a plug flow reactor, the plug flow reactor being operated under polymerisation conditions, wherein the reaction mixture is polymerised to a degree of polymerisation of at least 90%, to form polymer, and c) continuously removing polymer from the plug flow reactor.

Abstract: [Summary] The present invention relates to an apparatus for manufacturing polymer particles and a method for manufacturing the same. The present invention provides an apparatus and a method, by which polymer particles having excellent monodispersity and homogeneous physical properties, such as homogeneous cross-linking degree and polymerization degree, may be efficiently prepared. In the present invention, particles having excellent monodispersity with the desired particle diameter, and also having a high cross-linking degree or a core-shell or core-double shell structure may also be effectively prepared. In addition, the processes for manufacturing said polymer particles are exceptionally reproducible in the present invention.

Abstract: 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.

Abstract: 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.

Abstract: 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 BF3/methanol catalyst complex, to reaction conditions suitable for causing at least a portion of the isobutylene to undergo polymerization to form a polyisobutylene product including polyisobutylene molecules. At least a fraction of the polyisobutylene molecules thus produced have alpha position double bonds and the polyisobutylene product has a number average molecular weight (MN) and a polydispersity index (PDI). The concentration of the diluent in the reaction admixture may be manipulated to control or change any one or more of (a) the relative size of the fraction, (b) the number average molecular weight of the product, (c) the polydispersity index of the product and (d) the relative size of the portion.

Abstract: The present invention relates to a method for degassing polymer powder comprising flushing the polymer powder in a first chamber with a first flow of flushing gas, transferring the polymer powder into a second chamber and flushing the polymer powder with a second flow of flushing gas in said second chamber. The present invention also relates to a system suitable for carrying out this method.

Abstract: 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 a) intensively mixing an aqueous solution of lactams with salts of diamines and dicarboxylic acids under elevated pressure which is greater than the vapor pressure of the mixture which arises in a mixing apparatus at a temperature of from 80 to 300° C., b) feeding the mixture thus obtained to a heated helical tube evaporator in which a liquid phase and a vapor phase form at a temperature of from 140 to 300° C.

Abstract: 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.

Abstract: A Polymerisation process and a loop reactor comprising polymerising olefins in a liquid diluent to produce a liquid slurry containing particles of normally solid polymer within the loop reactor, allowing the polymer to settle in a settling leg, periodically opening a 180° rotating product take-off valve located at the end of the settling leg to allow a charge of particles to flow out of the settling leg, the product take-off valve being operated by a pneumatically driven double-acting actuator, the pneumatic system being regulated by a system comprising pneumatic control valves, the improvement which consists in using automatic control valves, which are automatic v-ball valves.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus of a polycarbonate resin having polymerization tanks is provided. In supplying a molten reactant to a liquid phase in a polymerization tank, or supplying the molten reactant to a gas phase in the polymerization tank by an insertion pipe, in at least one polymerization tank, and/or producing a polycarbonate resin by an ester exchange reaction between an aromatic dihydroxy compound and a carbonic diester by using three vertical polymerization tanks and one horizontal polymerization tank, a wall surface temperature T of a distillation pipe is set higher than a boiling point t1 of by-produced phenol such that the relationship of the boiling point t1 of the by-produced phenol under a pressure in at least a third vertical polymerization tank, the wall surface temperature T of the distillation pipe and an inner temperature t2 of the third vertical polymerization tank satisfies t1<T?t2.

Abstract: The invention relates to an improved process for the manufacture of an olefin polymer composition in which corrosive trace cocatalyst and catalyst residues are removed from the hydrocarbon gas recycle stream prior to compression and re-use in the polymerization zone(s).

Abstract: This invention relates to a process to polymerize olefins comprising contacting propylene, at a temperature of 65° C. to 150° C. and a pressure of 1.72 to 34.

Abstract: 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.

Abstract: 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.

Abstract: Process comprising polymerizing in a loop reactor of a continuous tubular construction 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 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The present invention relates to a process for the preparation of a propylene homo- or copolymer, comprising the following steps: (i) feeding propylene and hydrogen, and optionally one or more comonomers, to a reactor R1, wherein the hydrogen is fed to the reactor R1 in a periodically varying amount, (ii) preparing a first fraction of the propylene homo- or copolymer in the reactor R1 in the presence of a catalyst, (iii) transferring the first fraction to a reactor R2, and (iv) preparing a second fraction of the propylene homo- or copolymer in the reactor R2, wherein the melt flow rate MFR (2.16 kg, 230° C.) of the propylene homo- or copolymer is higher than the melt flow rate MFR (2.16 kg, 230° C.) of the first fraction.

Abstract: 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.

Abstract: 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 (Mw/Mn) from about 2 to about 30, a melt index (I2) from about 0.1 to about 50 grams per 10 minutes, and further comprising sulfur from about 5 to about 4000 parts per million. The amount of sulfur is also determined based upon the total weight of the ethylene-based polymer. Also disclosed is process for making an ethylene-based polymer which includes the steps of splitting a process fluid for delivery into a tubular reactor; feeding an upstream process feed stream into a first reaction zone and at least one downstream process feed stream into at least one other reaction zone, where the process fluid has an average velocity of at least 10 meters per second; and initiating a free-radical polymerization reaction.

Abstract: A process for the preparation of a propylene copolymer composition having a Flexural modulus lower than 500 MPa, a total ethylene content higher than 9% and a Xylene soluble fraction at room temperature higher than 20% comprising at least one polymerization step carried out in a gas-phase polymerization reactor comprising at least two interconnected polymerization zones said process being characterized by the fact that at least 30% by weight of said xylene soluble fraction is produced in the polymerization step carried out in a gas-phase polymerization reactor comprising at least two interconnected polymerization zones.