Abstract: PROBLEM There is provided a method for producing polylactic acid, which is capable of obtaining polylactic acid at low cost, and having high molecular weight. SOLUTION A method for producing polylactic acid by polymerizing molten lactide using at least one reactor having plug flow characteristics with ?(?), calculated from the following FORMULA (1), of 0.3 or smaller: ?(?)=?0?(E(?)×ABS(1??))d???(1) in the Formula (1), E(?) is a residence time distribution function determined by impulse response by starch syrup having a viscosity of 3 Pa·s, and ? is ratio of elapsed time ? and mean residence time ?0.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: There is provided a method capable of producing a methacrylic-based polymer excellent in pyrolysis resistance and excellent in fabricability in a high productivity. The method for producing a methacrylic-based polymer includes the following steps (1) and (2): step (1) of using a complete mixing reactor (A) to thereby obtain the first syrup, including specific steps; step (2) of using a reaction apparatus (D) including a plug flow mixer (B) and a plug flow reactor (C) to thereby obtain the second syrup, including specific steps.

Abstract: Process for transferring polyolefin particles from a first gas-phase polymerization reactor to a second gas-phase polymerization reactor in a multistage polymerization of olefins carried out in at least two serially connected gas-phase polymerization reactors, wherein the first gas-phase reactor is a fluidized-bed reactor comprising a gas distribution grid and a settling pipe, which is integrated with its upper opening into the distribution grid and contains a bed of polyolefin particles which moves from top to bottom of the settling pipe, the process comprising the steps of introducing a fluid into the settling pipe in an amount that an upward stream of the fluid is induced in the bed of polyolefin particles above the fluid introduction point; withdrawing polyolefin particles from the lower end of the settling pipe; and transferring the withdrawn polyolefin particles into the second gas-phase polymerization reactor, process for polymerizing olefins comprising such a process for transferring polyolefin partic

Abstract: Disclosed is a process for making an acid dye stain-resistant nylon resin in a continuous multi stage polymerization process. The process provides an acid dye stain-resistant nylon resin of requisite molecular weight at high production rates and a high sulfur content. Also disclosed are fibers, yarns, and textiles comprising the acid dye stain-resistant nylon resin.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: An ethylene-based polymer composition has been discovered and is characterized by a Comonomer Distribution Constant greater than about 45. The new ethylene-based polymer compositions are useful for making many articles, especially including films. The polymers are made using a metal complex of a polyvalent aryloxyether.

Abstract: The invention relates to a continuous polymerization process for preparing a random ethylene interpolymer which comprises: (A) polymerizing ethylene, and an ?-olefin comonomer selected from propylene and/or 1-butene, and mixtures thereof, under continuous random polymerization conditions in the presence of single site catalyst system employing an ionic activator having cyclic ligands shielding a central charge bearing atom, at a temperature of 140° C. to 250° C. at a conversion of ethylene of 80 to 99% and a comonomer conversion of from at least 20%; and (B) devolatilizing the polymer to provide an ethylene copolymer having a density of from 0.85 to 0.92 g/cm3, an MI of from 0.01 to 100 g/10 min and an I21/I2 of from 30 to 400.

Abstract: Techniques are provided for catalyst preparation. A system for catalyst preparation may include an agitator disposed inside a polymerization catalyst tank and configured to mix a polymerization catalyst and a solvent to generate a polymerization catalyst solution. The system may also include a heating system coupled to the polymerization catalyst tank and configured to maintain a temperature of the polymerization catalyst solution above a threshold. The system may also include a precontactor configured to receive feed streams comprising an activator and the polymerization catalyst solution from the polymerization catalyst tank to generate a catalyst complex. The system may also include a transfer line configured to transfer the catalyst complex from an outlet of the precontactor to a reactor.

Abstract: The present invention discloses a method for transforming a single reactor line into a double reactor line wherein the existing single reactor line is equipped with a flash tank for separating the solid polymer product from the flash vapor and wherein the vapor is sent to a system of at least two separating columns allowing the separation of its constituents into monomer, diluent and comonomer.

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

Abstract: Process for the preparation of a polyolefin polymer by continuously polymerizing one or more olefin monomers in suspension at temperatures of from 40° C. to 120° C. and pressures of from 0.1 to 10 MPa in the presence of a polymerization catalyst in at least one polymerization reactor, comprising a) withdrawing a suspension of solid polyolefin particles in a suspension medium from the polymerization reactor, wherein the suspension has a temperature of from 65° C. to 120° C.; b) feeding the suspension withdrawn from the polymerization reactor to a moderating vessel; c) keeping the suspension in the moderating vessel at a temperature of from 60° C. to 85° C. for a time sufficiently long that the mean residence time of the suspension in the moderating vessel is at least 5 min; d) withdrawing suspension from the moderating vessel; e) cooling the suspension withdrawn from the moderating vessel to a temperature of from 20° C. to 55° C.

Abstract: A novel polymer composition is described comprising ethylene homopolymers and/or copolymers of ethylene with C3-C8-alpha-olefins which polymer composition has a density of from 0.940 to 0.949 g/cm3, a melt index (HLMI) according to DIN EN ISO 1133:2005, condition G at 190° C. and 21.6 kg, of from 3 to 7 g/10 min. and a Hostalen Long Chain Branching Index (HLCBI) of from 3 to 8, and which polymer composition is produced by polymerisation with one or more Ziegler catalysts in a series of at least two polymerization reactors. The new polymer composition can in particular be used for blow moulding of intermediate bulk containers.

Abstract: The present invention relates to a new polymerization process which is suitable for polymerizing high molecular weight products of high viscosity such as polycarbonates and polystyrenes in reasonable time. The present invention achieves the above-identified object by means of a polymerization process, wherein at least in the final stages of the polymerization reaction, two different types of mechanical mixing means are employed as alternatives, designated first and second mixing means. The first mixing means do generate new surfaces in the material to be treated by means of mechanical mixing and by means of gravity driven mixing, while the second mixing means do generate new surfaces in the material to be treated not by means of mechanical mixing and only by means of gravity driven mixing.

Abstract: Methods and systems for preparing catalyst, such as chromium catalysts, are provided. The valence of at least a portion of the catalyst sent to an activator is changed from Cr(III) to Cr(VI). The catalyst is prepared or activated continuously using a fluidization bed catalyst activator.

Abstract: The invention provides a method and apparatus for continuously feeding wet gel polymers into a drying step of a dry polymer synthesis operation. A number of pistons are arranged having inner chambers through which monomers and other reagents are fed and polymerized into wet gel polymers. Each piston operates according to a coordinated schedule so that as one piston finishes extruding polymer into the drying step, a second piston has completed polymerizing more polymer and continues to feed more polymer without interruption. The then finished is re-fed more reagents so as to be ready again when needed next. As a result, cost effective continuous feeding can be achieved without the contamination and impurity problems that have plagued previous attempts to accomplish this.

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

Abstract: 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.

Abstract: Disclosed herein are processes for preparing procatalyst compositions and polymers, i.e., propylene-based polymers, produced therefrom. The present procatalyst compositions improve catalyst selectivity and also increase the bulk density of the formant polymer.

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

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A technique for polymerizing ethylene on catalyst in a first polymerization reactor and in a second polymerization reactor to form polyethylene particles, and controlling particle size of the polyethylene particles.

Abstract: The present invention discloses a method for transforming a single reactor line into a double reactor line wherein the existing single reactor line is equipped with a flash tank for separating the solid polymer product from the flash vapour and wherein the vapour is sent to a system of at least two separating columns allowing the separation of its constituents into monomer, diluent and comonomer.

Abstract: The present invention relates to a heterophasic polypropylene composition with rather high melt flow rate, high stiffness, acceptable impact properties and an advantageous balance between stiffness and transparency. Still further, the present invention is also directed to a process for producing the inventive polypropylene composition, to an article made of the inventive polypropylene composition and to the use of the inventive polypropylene composition for the production of films and molded articles, such as thin-walled plastic containers for packaging. The inventive heterophasic polypropylene composition comprises at least a propylene homopolymer fraction, a propylene random copolymer fraction, two different ethylene-propylene rubber fractions and an ethylene homo- or copolymer fraction.

Abstract: The invention relates to a process for producing water-absorbing polymer particles with improved permeability, comprising the steps of polymerization, drying, grinding, classification and thermal surface postcrosslinking, with pneumatic conveying between grinding and classification.

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

Abstract: A slurry process for the polymerisation of ethylene is disclosed, which takes place in a reactor system comprising one or more reactors in series, having a characteristic such that the average polymerisation productivity [kg PE/kgcata] per unit ethylene per hour aI during operation at any first residence time rI is less than 1.7 (a2r2 ?aIrI)/(r2?rI), where a2 is the average polymerisation productivity [kgPE/kgcata] per unit ethylene per hour during operation at any second residence time r2 where r2>rI, a2 and r2 being measured either in the same reactor in the case of a single reactor polymerisation, or in a reactor subsequent to the reactor in which aI and rI are measured in the case where the polymerisation takes place in more than one reactor, and wherein the specific yield of the reactor system is greater than 0.

Abstract: The present invention provides an ethylene-based polymer composition characterized by a Comonomer Distribution Constant in the range of from greater than 45 to less than 400, wherein the composition has less than 120 total unsaturation unit/1,000,000C, and method of producing the same.

Abstract: A process is taught, comprising polymerizing ethylene in the presence of a catalyst to form a crystalline ethylene-based polymer having a crystallinity of at least 50% as determined by DSC Crystallinity in a first reactor or a first part of a multi-part reactor and reacting the crystalline ethylene-based polymer with additional ethylene in the presence of a free-radical initiator to form an ethylenic polymer in at least one other reactor or a later part of a multi-part reactor.

Abstract: The present invention discloses a method for transforming a single reactor line into a double reactor line wherein the existing single reactor line is equipped with a flash tank for separating the solid polymer product from the flash vapor and wherein the vapor is sent to a system of at least two separating columns allowing the separation of its constituents into monomer, diluent and comonomer.

Abstract: This invention is related to the preparation of polyethylene pipe resins suitable for transporting hot and cold water containing chlorine dioxide.

Abstract: An epoxy resin with amine functionality is manufactured continuously through a first reaction zone in which an epoxide-functional resin is made by ring-opening addition, a second reaction zone in which the resin is reacted with amine to make an epoxide-functional product, and a third reaction zone in which the epoxide functional product is reacted with amine to make the epoxy resin with amine functionality. In other embodiments, some amine may be added in the first reaction zone to produce an epoxide functional product, with elimination of the second reaction zone, or all of the amine reactant may be added in the first reaction zone to produce an amine functional product, with elimination of both the second and third reaction zones. Optionally, solvent may be removed in an evaporation zone and recycled into the continuous process and further zones may be included to incorporate crosslinker, additives, and to emulsify the resin.

Abstract: Methods for controlling the weight ratio of a higher molecular weight component to a lower molecular weight component of an olefin polymer are disclosed. This weight ratio can be increased as polymerization reaction temperature and/or catalyst system residence time are increased.

Abstract: 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.

Abstract: The present invention relates to a thermoplastic polyolefin elastomer composition in powder form comprising (i) an olefin block copolymer or (ii) a substantially linear ethylene polymer and/or a linear ethylene polymer and propylene polymer blend. Said composition demonstrates good pulverizing and flow characteristics at ambient temperature. In another aspect, this invention relates to a process for preparing said thermoplastic polyolefin elastomer powder and applications for using said powder. In a further aspect, this invention relates to paper transfer molding said thermoplastic polyolefin elastomer composition into artificial leather, particularly for skins for automotive interior applications such as instrument panels.

Abstract: The invention provides a method and apparatus for continuously feeding wet gel polymers into a drying step of a dry polymer synthesis operation. A number of pistons are arranged having inner chambers through which monomers and other reagents are fed and polymerized into wet gel polymers. Each piston operates according to a coordinated schedule so that as one piston finishes extruding polymer into the drying step, a second piston has completed polymerizing more polymer and continues to feed more polymer without interruption. The then finished is re-fed more reagents so as to be ready again when needed next. As a result, cost effective continuous feeding can be achieved without the contamination and impurity problems that have plagued previous attempts to accomplish this.

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

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

Abstract: The invention relates to an improved process for manufacturing an olefin polymer composition, in particular polyethylene, that incorporates two or more reaction zones in an optimized configuration that ease product transitions and allows for improved reactor quality control.

Abstract: A composition suitable for use in pressure pipes and pipe fittings is disclosed comprising polymer of ethylene and from 0.5 to 5 wt % of a C4-C8 alpha-olefin which has a natural density of 935-956 kg/m3, a melt index MI5 of 0.15-0.5 g/10 min, a dynamic complex viscosity at 100 rad/s and 190° C. (?100) of no more than 2500 Pa·s, a relationship between ?100 and dynamic complex viscosity measured in Pa·s at 0.01 rad/s and 190° C. (?0.01) defined by the equation ?0.01>115000+30. ?100, and an environmental stress crack resistance as measured by a notched pipe test performed according to ISO13479:1997 on 110 mm SDR 11 pipes at 80° C. and a pressure of 9.2 bar, of greater than 1000 hours, or: wherein the C4-C8 alpha-olefin is 1-hexene or 1-octene.

Abstract: The invention relates to a process and apparatus for preparing an ethylene polymer by free radical polymerization under ultra-high pressure. The polymerization is carried out in an autoclave reactor in the presence of a free radical initiator. The autoclave reactor is characterized by having one or more elongated baffles affixed to the interior reactor wall.

Abstract: The invention relates to a polypropylene composition showing a high melt flow rate and simultaneously high stiffness and a process for the production thereof. The invention further relates to a material comprising the inventive polypropylene.

Abstract: A manufacturing system for producing polyolefin includes a polymerization reactor, a flash chamber, and a purge column. In certain embodiments, the purge column may receive a solids stream directly from the flash chamber. Further, the purge column may function as a feed tank for an extruder within an extrusion/loadout system. According to certain embodiments, the manufacturing system may be configured to consume less than 445 kilowatt-hours of energy per metric ton of polyolefin produced based on consumption of electricity, steam, and fuel gas.

Abstract: A method for continuously producing a thermoplastic resin from a conjugated diene includes: primarily polymerizing a conjugated diene monomer with an aromatic vinyl monomer in a first solvent in a first reactor, and feeding a hydroxyl group-containing polymerization inhibitor and a polar hydrocarbon to the first reactor to prepare a rubber solution; and adding an aromatic vinyl monomer and a monomer copolymerizable with the aromatic vinyl monomer to the rubber solution, and subjecting the mixture to secondary polymerization in a second solvent of the same kind as the first solvent in a second reactor. The method can provide a thermoplastic resin that can have excellent color and low gloss characteristics.

Abstract: This invention is related to the preparation of polyethylene pipe resins suitable for transporting hot and cold water containing chloramine.

Abstract: The invention relates to A process for the polymerization of ethylene to produce a polyethylene resin in at least two slurry loop reactors connected to each other in series, the resin having a bimodal molecular weight distribution, a molecular weight distribution MWD of at least 7.0, an HLMI of from 1 to 100 g/10 min, and a density of from 0.935 to 0.960 g/cm3, wherein in one reactor 30 to 47 wt % based on the total weight of the polyethylene resin of a high molecular weight (HMW) polyethylene fraction is produced having an HL275 of from 0.05 to 1.8 g/10 min (the equivalent of HLMI of from 0.01 to 1.56 g/10 min), a density of from 0.925 to 0.942 g/cm3 and an MWD of at least 5.0, and in the other reactor a low molecular weight (LMW) polyethylene fraction is produced having an HLMI of from 10 to 1500 g/10 min and a density of from 0.960 to 0.975 g/cm3, in the presence of a Ziegler-Natta catalyst system.

Abstract: A virgin granular polymer comprising polymer particles wherein at least 90% by weight of the granular polymer particles, have an I21 that is within two standard deviations of a mean I21 of the granular polymer, the ratio of the standard deviation of I21 to the mean of the granular polymer is less than 0.2 and the ratio of the standard error of a linear fit to the mean of the granular polymer is less than 0.1, and further wherein the virgin granular polymer has an I21 less than or equal to 70 and/or further wherein at least 90% by weight of the granular polymer particles, have a density that is within two standard deviations of a mean density of the granular polymer, the ratio of the standard deviation of the mean density of the granular polymer to the mean density of the granular polymer is less than 0.002 and the ratio of the standard error of a linear fit to the mean of the density is less than 0.001, and further wherein the virgin granular polymer has an I21 less than or equal to 70 is provided.

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

Abstract: In a process for making a copolymer, a first product stream comprising a semi-crystalline polymer and a chain terminating agent is produced in a first reactor system. The first product is provided to a second reactor system wherein a low crystallinity polymer is produced in the presence of the semi-crystalline polymer. At least a portion of the chain terminating agent is removed from the second reactor system by an in-situ process.

Abstract: The present invention relates to a heterophasic polymer composition which comprises (i) a matrix comprising a propylene homopolymer and/or a propylene copolymer having an amount of comonomer units of less than 1.0 wt %, and (ii) an elastomeric polypropylene which is dispersed within the matrix and comprises comonomer units derived from ethylene and/or a C4 to C12 alpha-olefin; and wherein the heterophasic polymer composition has an amorphous fraction AM in an amount of 2.0 to 7.5 wt %, and the amorphous fraction AM has an amount of ethylene- and/or C4 to C12 alpha-olefin-derived comonomer units of 20 to 45 wt %.