Abstract: A polymerization reactor for producing aqueous polymer dispersions by radically initiated emulsion polymerization of one or more ethylenically unsaturated monomers in the presence of one or more protective colloids and/or emulsifiers, is cleaned by initially charging an aqueous mixture comprising one or more ethylenically unsaturated monomers, one or more protective colloids and/or emulsifiers, but no oxidation initiator, the proportion of ethylenically unsaturated monomers being 20 to 70% by weight of the aqueous mixture, heating the aqueous mixture to a temperature of 50° C. to 100° C. for 5 minutes to 3 hours, adding one or more initiators and optionally further starting materials, initiating polymerization, removing the aqueous polymer dispersion thus obtained from the polymerization reactor and post-treating the dispersion to remove wall deposits detached during the process.

Abstract: A weight measuring device includes a top layer including a plurality of first flats and at least one bi-stable spring band. The plurality of first flats are connected to each other via the at least one bi-stable spring band. The weight measuring device further includes a bottom layer including a plurality second flats connected the plurality of first flats. The weight measuring device further includes at least one force sensor interposed between the top layer and the bottom layer. The weight measuring device further includes a processor configured to determine a weight of an object placed on the top layer or the bottom layer based on signals generated from the at least one force sensor.

Abstract: Provided herein are methods and systems for at least partially deactivating at least one component of a reactor effluent from gas phase polyolefin polymerization processes utilizing at least one glycol.

Abstract: A microfluidic device for non-invasively and passively accessing interstitial fluid from a patient includes a substrate containing multiple vertical micro channels therethrough, wherein at a first end of each of the multiple vertical micro channels a microheater is formed for controllably ablating a portion of dry dead skin cells to access the interstitial fluid; and wherein at a second end of each of the multiple vertical micro channels is a horizontal micro channel for receiving accessed interstitial fluid from a vertical micro channel and guiding the accessed interstitial fluid to a common collection port.

Abstract: Provided is an apparatus for preparing oligomer including: a reactor for carrying out oligomerization reaction by supplying a monomer stream and a solvent stream; and line 1 and line 2 which are separately provided in a lower side of the reactor, wherein line 1 includes a first level control valve and line 2 includes a second level control valve, and the reactor is periodically alternately operated in first operation mode and second operation mode, thereby switching a pipe through which the product is discharged, so that a plugging phenomenon of the pipe through which the product is discharged and the valve can be prevented.

Abstract: A system for determining the presence of cell-free non-coding RNA (cfNCR) biomarkers in interstitial fluid includes a microfluidic device for non-invasively and passively accessing interstitial fluid from a patient. The microfluidic device is formed of a substrate containing multiple vertical micro channels therethrough, wherein at a first end of each of the multiple vertical micro channels a microheater is formed for controllably ablating a portion of dry dead skin cells to access the interstitial fluid; and wherein at a second end of each of the multiple vertical micro channels is a horizontal micro channel for receiving accessed interstitial fluid from a vertical micro channel and guiding the accessed interstitial fluid to a common collection port.

Abstract: A method for controlling the start up conditions in a gas phase polymerization process is provided. An inventory can be calculated for each monomer, comonomer, and hydrogen sufficient to produce a polyethylene polymer having desired properties, such as, a certain melt index and/or density.

Abstract: The present invention relates to a process for the production of a polymer using a compound comprising at least 2 unsaturated carbon-carbon bonds, wherein the process comprises a polymerization section and a purification section, wherein the product from the polymerization section is subjected in the purification section to a sequence of purification steps comprising: removal of the vapor phase from the product from the polymerization section by means of flash separation to obtain a first vapor phase and a polymerization product; subjecting the first vapor phase to a compression and condensation treatment to obtain a second vapor phase and a condensed monomer phase; wherein the purification steps are conducted in this order. Such process allows for the optimal utilisation of raw materials in the polymerization process.

Abstract: A radiation curable resin composition comprising: (A) metal oxide particles; (B) at least one photoinitiator, preferably a radical photoinitiator, or any mixture thereof; (C) at least one acrylate or methacrylate component with a ClogP higher than 2, preferably higher than 4, more preferably higher than 5, or any mixture thereof; (D) at least one monofunctional acrylate or methacrylate diluent component, preferably with a viscosity below 40 mPa·s at 20° C., or any mixture thereof; (E) at least one acrylate or methacrylate component with functionality equal or higher than 3, preferably 3 or 4, or any mixture thereof; can be advantageously used, for example, in multilayer barrier stacks for the production of organic opto-electric or opto-electronic device, such as Organic Light Emitting Diode (OLED).

Abstract: A method for feeding an antistatic compound to a polymerization reactor comprising the steps of: a) dispersing, under mixing conditions, a catalyst powder and an antistatic compound in an oil, so as to form a suspension of catalyst powder and antistatic compound in said oil; b) successively adding, under mixing conditions, a molten thickening agent to said suspension from step a), while maintaining said suspension at a temperature such that said thickening agent solidifies on contact with said suspension; c) transferring the product obtained from b) to a polymerization reactor.

Abstract: A process for the preparation of ethylene polymers comprising polymerizing ethylene, optionally with one or more ?-olefin comonomers, in the presence of: (i) a solid catalyst component comprising titanium, magnesium, halogen and optionally an internal electron-donor compound, (ii) an aluminum alkyl compound, and (iii) an antistatic compound selected among the hydroxyesters with at least two free hydroxyl groups, wherein the weight ratio of aluminum alkyl compound to solid catalyst component is higher than 0.80 and the weight ratio of antistatic compound to aluminum alkyl compound is higher than 0.10.

Abstract: A process and apparatus for producing olefin polymers are disclosed, comprising: a. polymerizing one or more olefins in the gas phase, in the presence of an olefin polymerization catalyst, whereby growing polymer particles flow along a cylindrically-shaped downward path in densified form under the action of gravity so as to form a densified bed of downward-flowing polymer particles b. allowing said polymer particles to flow through a restriction of the densified bed, such restriction being positioned in a restriction zone extending from the bed upward to a distance of 15% of the total height of the densified bed; and c. metering an antistatic agent through a feed line connected to the densified bed at a feed point being located in a feed zone extending from the top of the restriction upward, to a distance five times the diameter of the section of the densified bed above the restriction.

Abstract: A resist underlayer film-forming composition for forming a resist underlayer film having both dry etching resistance and heat resistance. A resist underlayer film-forming composition comprising a polymer containing a unit structure of Formula (1): In Formula (1), R3 is a hydrogen atom, and both n1 and n2 are 0. A method for producing a semiconductor device comprising the steps of: forming an underlayer film on a semiconductor substrate using the resist underlayer film-forming composition; forming a hard mask on the underlayer film; further forming a resist film on the hard mask; forming a resist pattern by irradiation with light or electron beams and development; etching the hard mask using the resist pattern; etching the underlayer film using the hard mask patterned; and fabricating the semiconductor substrate using the patterned underlayer film.

Abstract: A process for polymerizing ethylene to produce an ethylene-based polymer including contacting ethylene with a Ziegler-Natta procatalyst, an alkylaluminum cocatalyst and a self limiting agent selected from the group of aliphatic, cycloaliphatic, substituted cycloaliphatic or aromatic esters, anhydrides and amides such that the self limiting agent reduces polymerization rates to no greater than 40% of the polymerization rate in the absence of the self limiting agent at temperatures equal to or greater than 120° C. is provided.

Abstract: A catalyst composition may include a precontacted mixture of an olefin polymerization catalyst and an agent including an ammonium salt. The catalyst activity of the catalyst composition in the presence of water may be greater than if no ammonium salt were present in the catalyst composition. The ammonium salt may include a tetraalkylammonium salt, and the olefin polymerization catalyst may include a metallocene compound.

Abstract: Various methods and systems for using oxygen in a polyolefin polymerization reactor system are provided. In certain embodiments, the methods are performed in conjunction with a polymerization reactor system such as a gas-phase reactor system.

Abstract: A polymerization process includes contacting the following in a gas-phase reactor system under polymerization conditions for making a polymer product: a metallocene-based catalyst system including a supported constrained geometry catalyst, at least one monomer, and an additive selected from a group consisting of an aluminum distearate, an ethoxylated amine, and a mixture thereof. The additive may be selected from a group consisting of an aluminum distearate, an ethoxylated amine, polyethylenimines, and other additives suitable for use in the production of polymers for food contact applications and end products, including a mixture of a polysulfone copolymer, a polymeric polyamine, and oil-soluble sulfonic acid, in a carrier fluid, and mixtures thereof.

Abstract: 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.

Abstract: The present invention relates to an ethylene homo- or copolymerization process, characterized in that an inhibitor is added to the reaction mixture or any of its components before the reaction mixture is fed to the reaction zone. The present invention further relates to the use of an inhibitor to reduce fouling in an ethylene homo- or copolymerization process.

Abstract: A method for altering the polymer architecture of ethylene copolymers made with a supported phosphinimine polymerization catalyst. The method involves changing the amount of a catalyst modifier added to a reactor separately from or together with a supported phosphinimine polymerization catalyst.

Abstract: A supported catalyst system comprising a phosphinimine ligand containing catalyst on a porous inorganic support treated with a metal salt has improved reactor continuity in a dispersed phase reaction in terms of initial activation and subsequent deactivation. The resulting catalyst has a lower consumption of ethylene during initiation and a lower rate of deactivation. Preferably the catalyst is used with an antistatic agent.

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 method for feeding an antistatic compound to a polymerization reactor, the method comprising the steps of: a) dispersing, under mixing conditions, a catalyst powder and an antistatic compound in a liquid medium, so as to form a suspension of the catalyst powder and of the antistatic compound in the liquid medium; b) transferring the obtained suspension to a polymerization reactor.

Abstract: Described herein are methods for monitoring and restoring electrical properties of polymerization reactor wall films. The method may comprise using a reactor wall monitor to monitor and determine an electrical property, such as the bed voltage or breakdown voltage, of the wall film. The method may further comprise adding continuity additive to the reactor and/or adjusting the feed rate of continuity additive being added to the reactor in response to the measured electrical property.

Abstract: A polymerization process is disclosed comprising polymerizing an olefin to form an olefin-based polymer in a polymerization reactor; and introducing a polyetheramine additive to the polymerization reactor. The process may further comprise monitoring static in the polymerization reactor; maintaining the static at a desired level by use of a polyetheramine additive, where the polyetheramine additive is present in the reactor in the range from about 0.1 to about 500 ppmw, based on the weight of polymer produced by the process.

Abstract: The invention provides a method for preventing fouling in chemical equipment, comprising adding an antifouling agent which comprises a polyoxyalkylene polymer having Mn of 30,000 or less to a component in the chemical equipment.

Abstract: Olefin polymerization is carried out with a single site polymerization catalyst in the presence of a continuity additive. The continuity additive is a cocktail containing one or more dialkanolamide derived from a fatty acid, an oil soluble sulfonic acid and a dialkanolamine.

Abstract: A polymerization process is disclosed comprising polymerizing an olefin to form an olefin-based polymer in a polymerization reactor; and introducing a polyetheramine additive to the polymerization reactor. The process may further comprise monitoring static in the polymerization reactor; maintaining the static at a desired level by use of a polyetheramine additive, where the polyetheramine additive is present in the reactor in the range from about 0.1 to about 500 ppmw, based on the weight of polymer produced by the process.

Abstract: Methods for gas phase olefin polymerization are provided. The method can include combining a spray dried catalyst system with a diluent to produce a catalyst slurry. The catalyst system can include a metallocene compound. Ethylene, a continuity additive, and the catalyst slurry can be introduced to a gas phase fluidized bed reactor. The reactor can be operated at conditions sufficient to produce a polyethylene. The spray dried catalyst system can have a catalyst productivity of at least 12,000 grams polyethylene per gram of the catalyst system.

Abstract: The current invention provides a method of improving the efficiency of one or more heat exchangers used in cooperation with a high temperature solution polymerization process. Addition of surface active agents, such as C6 to C22 carboxylic acids, to a two phase liquid-liquid polymer solution downstream of a reactor system and upstream of a heat exchanger system can increase the efficiency of heat exchange by more than 10 %.

Abstract: Systems and methods for monitoring a polymerization reactor are provided. The method can include estimating an acoustic condition of a polymer produced in a reactor. The method can also include estimating a stickiness control parameter of the polymer produced in the reactor. The method can further include pairing the acoustic condition with the stickiness control parameter to provide a paired acoustic condition and stickiness control parameter.

Abstract: A method for cleaning a distributor plate in a fluidized bed polymerization reactor system according to one embodiment includes, in a first mode, operating with about a normal, baseline value of superficial gas velocity in a fluidized bed polymerization reactor system having a reactor vessel, a recycle line, and a distributor plate in the reactor vessel near an inlet of the reactor vessel. In a second mode, the superficial gas velocity is increased above the baseline value of the first mode to a level sufficient to raise the temperature of the cycle gas at the inlet above an average temperature of the cycle gas at the inlet in the first mode, and to a level sufficient to dislodge foulant from holes in the distributor plate.

Abstract: Described herein in one embodiment is a plant for the continuous solution polymerization of one or more monomers in a solvent, e.g., a hydrocarbon solvent. In one aspect, the plant comprises a high pressure pump and at least one heat exchanger downstream of the pump. In another aspect a feed is cooled by three heat exchangers which are refrigerated by means of a common three stage compressor. In another aspect, the plant comprises a primary reactor and a secondary reactor arranged to operate in parallel, in which the ratio of volume of the primary reactor to the secondary reactor is in the range of 60:40 to 95:5. In another aspect, a method of defouling a heat exchanger is provided in which the level of liquid refrigerant in the heat exchanger is temporarily lowered.

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

Abstract: A method and apparatus are disclosed for controlling product discharge from a fluidized bed reactor and for minimizing the loss of the unreacted monomer in the fluidizing gas upon removing the solid polymer product from the reactor. The method and apparatus utilize at least one detector in the product tank or its vent line and a control system in communication with the detector and the product tank fill valve, along with certain algorithms, to adjust by an iterative process, the product discharge time, thereby maximizing resin fill in the product tank and minimizing the lost reactor gas volume.

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

Abstract: The invention relates to a process for removing fouling on a surface, wherein the surface is contacted with an aqueous solution of a guanidine of formula R1R2N—C(?NH)—NR3R4??(I) wherein R1, R2, R3 and R4 may be the same or different and each of R1, R2, R3 and R4 is hydrogen or hydrocarbyl.

Abstract: A process for preventing or reducing polymer agglomeration and/or accumulation on or around the gas distribution grid in an olefin polymerization, fluidized-bed reactor. The process involves introducing one or more scouring balls into the reactor above the gas distribution grid, and carrying out olefin polymerization in the presence of the scouring balls. Also disclosed is a process for polymerizing olefins in a fluidized-bed reactor with reduced polymer agglomeration and/or accumulation on the gas distribution grid.

Abstract: A method for preventing or reducing agglomeration and/or accumulation on or around the gas distribution grid in a fluidized-bed vessel. The method involves introducing one or more scouring balls into the vessel above the gas distribution grid, and carrying out a fluidized-bed process in the presence of the scouring balls.

Abstract: The invention concerns methods for polymerization of olefins comprising contacting one or more monomers selected from ethylene and ?-olefins with a supported single site catalyst in the presence of one or more magnesium alkyl compounds wherein said magnesium alkyl is present during the major portion of said polymerization.

Abstract: The present invention relates to a bubble column reactor comprising a column reactor having a sparger plate dividing the column reactor into a top reaction compartment and a bottom compartment, characterized in that an inlet and outlet line for introducing and disposing a flushing medium are connected to the bottom compartment; and an operation method thereof.

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: Continuous feed of auxiliaries for the polymerization reaction of ethylene, propene, and other higher homologous olefins in the preparation of homo- and copolymers, avoiding production of inhomogeneities, such as lumps or chunks which are present because the condition of the auxiliaries is not suitable for precise metering, becomes possible when auxiliaries in paste or solid form, in particular antistatic auxiliaries, are subjected, prior to feed, to a heat treatment in the presence of a solvent at a temperature of from 20 to 80° C., and then recooled, and then fed to the polymerization reaction.

Abstract: A method for cleaning a distributor plate in a fluidized bed polymerization reactor system according to one embodiment includes, in a first mode, operating with about a normal, baseline value of superficial gas velocity in a fluidized bed polymerization reactor system having a reactor vessel, a recycle line, and a distributor plate in the reactor vessel near an inlet of the reactor vessel. In a second mode, the superficial gas velocity is increased above the baseline value of the first mode to a level sufficient to raise the temperature of the cycle gas at the inlet above an average temperature of the cycle gas at the inlet in the first mode, and to a level sufficient to dislodge foulant from holes in the distributor plate.

Abstract: Embodiments of the present invention relate to measuring and controlling static in a gas phase reactor polymerization. In particular, embodiments relate to monitoring carryover static in an entrainment zone during gas phase polymerization to determine the onset of reactor discontinuity events such as chunking and sheeting. Embodiments also relate to monitoring carryover static to determine the need for effective additions of continuity additives that minimize reactor static activity and thereby preventing discontinuity events.

Abstract: The present invention is directed to a process for the production of an alpha-olefin polymer, which process comprises feeding of at least one alpha-olefin to a mechanically stirred bed gas phase reactor containing particles of the alpha-olefin polymer and polymerizing the alpha-olefin in the presence of a catalyst based on a titanium compound and a magnesium compound, an aluminum-alkyl compound and optionally an organosilane donor, in which process an amount of less than 100 ppm of at least one compound selected from the group of ethoxylated amines, fatty acid esters, diethanol amides, ethoxylated alcohols, alkylsulfonates and alkylphosphates is present during the polymerization.

Abstract: Described herein in one embodiment is a plant for the continuous solution polymerization of one or more monomers in a solvent, e.g., a hydrocarbon solvent. In one aspect, the plant comprises a high pressure pump and at least one heat exchanger downstream of the pump. In another aspect a feed is cooled by three heat exchangers which are refrigerated by means of a common three stage compressor. In another aspect, the plant comprises a primary reactor and a secondary reactor arranged to operate in parallel, in which the ratio of volume of the primary reactor to the secondary reactor is in the range of 60:40 to 95:5. In another aspect, a method of defouling a heat exchanger is provided in which the level of liquid refrigerant in the heat exchanger is temporarily lowered.

Abstract: A polymerisation reactor comprising one or more circulation loops with one or more inlets for raw material, one or more outlets, and a circulation pump for circulating a reactor charge within the circulation loop. A by-pass line for by-passing the circulation pump connects a point of the loop upstream of the pump with a point downstream of the pump, both points being provided with a three way valve.

Abstract: The current invention provides a method of improving the efficiency of one or more heat exchangers used in cooperation with a high temperature solution polymerization process. Addition of surface active agents, such as C6 to C22 carboxylic acids, to a two phase liquid-liquid polymer solution downstream of a reactor system and upstream of a heat exchanger system can increase the efficiency of heat exchange by more than 10%.

Abstract: This invention relates to a process comprising contacting an polymerization reactor effluent with a fluorinated hydrocarbon and thereafter recovering olefin polymer, where the fluorinated hydrocarbon is present at 5 volume % to 99 volume % based upon the volume of the effluent and the fluorinated hydrocarbon, and where the polymerization is a continuous polymerization of at least 75 mole % of hydrocarbon monomers, based upon the total moles of monomer present in the reactor.