Abstract: The present invention is directed to the use of aluminum alkyl activators and co-catalysts to improve the performance of chromium-based catalysts. The aluminum alkyls allow for the variable control of polymer molecular weight, control of side branching while possessing desirable productivities, and may be applied to the catalyst directly or separately to the reactor. Adding the alkyl aluminum compound directly to the reactor (in-situ) eliminates induction times.

Abstract: The present invention relates to a supported, treated catalyst system and its use in a process for polymerizing olefin(s). More particularly, it provides a supported, treated catalyst system produced by a process comprising the steps of: (a) forming a supported bimetallic catalyst system comprising a first catalyst component and a metallocene catalyst compound; and (b) contacting the supported bimetallic catalyst system of (a) with at least one methylalumoxane-activatable compound.

Abstract: An apparatus for feeding a dry particulate solid into a pressurized vessel including: a solids reservoir; a rotating metering disc below the solids reservoir; a non-rotating component adjacent to the metering disc; a surface of contact between the metering disc and the non-rotating component, wherein the surface of contact comprises a low friction material; a drive shaft, a drive motor; a pickup section; and an injection tube is provided.

Abstract: Methods of tailoring polyethylenes are contemplated utilizing 0.5 to 70 volume percent oxygen containing gases. The tailoring occurs in a melt-conveying zone of a mixer/extruder, and not in the feed or melting zones of a mixer/extruder. The effect of tailoring is to decrease the haze and/or increase the gloss of blown films made from the tailored polyethylenes compared to similar polyethylenes that are extruded/mixed in the substantial absence of oxygen or oxygen containing gases.

Abstract: A process for the production of an ethylene alpha-olefin copolymer is disclosed, the process including polymerizing ethylene and at least one alpha-olefin by contacting the ethylene and the at least one alpha-olefin with a metallocene catalyst in at least one gas phase reactor at a reactor pressure of from 0.7 to 70 bar and a reactor temperature of from 20° C. to 150° C. to form an ethylene alpha-olefin copolymer. The resulting ethylene alpha-olefin copolymer may have a density D of 0.927 g/cc or less, a melt index (I2) of from 0.1 to 100 dg/min, a MWD of from 1.5 to 5.0. The resulting ethylene alpha-olefin copolymer may also have a peak melting temperature Tmax second melt satisfying the following relation: Tmax second melt>D*398?245.

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: A process to prepare a catalyst composition that includes combining catalyst precursors in a recycled organic reaction solvent; allowing the catalyst precursors to react to form a catalyst compound; and separating the formed catalyst compound from the reaction solvent is disclosed.

Abstract: Systems and methods for removing impurities from a feed fluid in a single vessel. A method generally includes, in single vessel, contacting a feed fluid passing through the vessel with a copper-based material for removing oxygen from the feed fluid; and contacting the feed fluid passing through the vessel with an adsorbent for removing at least one of water, carbon dioxide, and oxygenated hydrocarbons from the feed fluid.

Abstract: A rotary feeder for feeding a particulate material including: a cylindrical housing comprising a feeder inlet, a first feeder outlet, and a second feeder outlet; a rotor mounted in the cylindrical housing including a plurality of substantially impeller blades defining a plurality of circumferentially spaced pockets alignable with the feeder inlet, first feeder outlet, and second feeder outlet, and adapted to sweep a wall of the cylindrical housing as the rotor rotates in the cylindrical housing; a device for rotating the rotor; and a separating screen in the first feeder outlet to substantially prevent oversize material from exiting through the first feeder outlet, wherein each of the plurality of circumferentially spaced pockets will align with the feeder inlet to receive therein a particulate material and an oversize material through the feeder inlet, rotate in the cylindrical housing to align with the first feeder outlet and discharge the particulate material therefrom, and rotate in the cylindrical housin

Abstract: A process for the production of an ethylene alpha-olefin copolymer is disclosed. The process includes polymerizing ethylene and at least one alpha-olefin by contacting the ethylene and the at least one alpha-olefin with a metallocene catalyst in at least one gas phase reactor at a reactor pressure of from 0.7 to 70 bar and a reactor temperature of from 20° C. to 150° C. to form an ethylene alpha-olefin copolymer. The resulting ethylene alpha-olefin copolymer may have a density of 0.927 g/cc or greater and environmental stress crack resistance (ESCR) of 500 hr or more when measured according to ASTM 1693/B in 10% Igepal.

Abstract: Embodiments disclosed herein generally relate to olefin polymerization catalysts, and more specifically to chromium-based catalysts and methods of use of chromium-based catalysts for the production of polyolefins, and even more specifically to methods for controlling or tailoring the flow index response of chromium-based catalysts through the controlled addition of a reducing agent to the catalysts under controlled mixing conditions.

Abstract: A bimodal polyethylene composition that includes ethylene-derived units, and, optionally, one or more other olefin-derived units, wherein the bimodal polyethylene composition possesses a density of at least 0.940 g/cc, an average molecular weight (Mw) of from 200,000 to 370,000, a z-average molecular weight (Mz) of from 1,500,000 to 3,400,000 Daltons, and a z+1 average molecular weight (Mz+1) of from 2,500,000 to 6,800,000 Daltons, is provided in various embodiments. Articles made therefrom and methods of making the same are also provided.

Abstract: Bimodal polyethylene compositions and blow molded bottles made therefrom are provided. In at least one specific embodiment, the composition includes at least one high molecular weight polyethylene component having a molecular weight distribution (MWD) of about 6 to about 9, a short chain branch content of less than about 2 branches per 1,000 main chain carbons, and a Mz of about 1,100,000 or more. The composition also includes at least one low molecular weight polyethylene component where a ratio of weight average molecular weight of the high molecular weight polyethylene component to weight average molecular weight of the low molecular weight polyethylene component is about 20 or less. The polyethylene composition has a density of about 0.94 g/cc or more, an ESCR of about 600 hours or more, a percent die swell of about 70% or more, and may comprise at least 70% ethylene-derived units.

Abstract: Catalyst feed systems and processes utilizing such systems are described herein. Some embodiments disclosed herein relate to a process for improving the flowability of catalyst in a catalyst feed system, including providing a catalyst feed vessel with at least one heat exchange system for maintaining the catalyst system temperature below a critical flow temperature. Also disclosed is a catalyst feed system for the polymerization of olefins including a catalyst feed vessel; and a heat exchange system for maintaining a temperature of a catalyst within the catalyst feed vessel. Additionally disclosed is a process for polymerization of olefins including maintaining a supported catalyst in a catalyst feed vessel below a critical flow temperature of the catalyst; feeding the catalyst to a polymerization reactor; and contacting the catalyst with an olefin to form a polyolefin.

Abstract: Articles such as, for example, pipes or bottles, prepared from multimodal polyethylenes possessing a density from 0.940 to 0.965 g/cm3, and an I21 from 4 to 20 dg/min, and comprising a low molecular weight ethylene copolymer having a weight average molecular weight from 5,000 amu to 50,000 amu; and a high molecular weight ethylene copolymer having a weight average molecular weight from 60,000 amu to 800,000 amu, both components having a desirable balance of short chain branching making the multimodal polyethylene suitable for films, pipes, rotomolding applications and blow molding applications.

Abstract: A method for controlling a transition from an initial polymerization reaction to a target polymerization reaction in a manner that reduces significantly the amount of off-grade product having excessively low density produced during the transition, including steps of: during the transition, maintaining a first one of a concentration ratio and a feed ratio at an at least substantially constant value while implementing process changes in an effort to bring produced polymer into compliance with a target specification set and monitoring (without controlling) the other one of the concentration ratio and the feed ratio to generate first data; and during the transition, determining from the first data whether polymer having excessively low density is likely to be produced during the transition, and upon determining that polymer having excessively low density is likely to be produced during the transition, maintaining during the remaining portion of the transition the other ratio at a value that is at least substantia

Abstract: In some embodiments, a method of monitoring a resin-producing polymerization reaction in a fluid bed reactor system to generate reaction parameter data in on-line fashion, determining an indicator of at least one of entropy and complexity (for example, Kolmogorov or Shannon entropy) of each of at least two subsets of the reaction parameter data, and optionally also determining from at least one value of the indicator (for example, from a time series of Kolmogorov or Shannon entropy values) an indication of at least one of degree of resin stickiness, an approach to or imminence of resin stickiness, and an approach to or imminence of an unsafe or undesired reactor operating condition (e.g., that can result in sheeting or chunking). Optionally also, the reaction is controlled in response to at least one value of the indicator, for example, in an effort to prevent the occurrence of sheeting or another discontinuity event or to maintain the reactor in a stable, non-sticking condition.

Abstract: A process for polymerizing olefin(s) utilizing a cyclic bridged metallocene catalyst system to produce polymers with improved properties is provided. The catalyst system may include a cyclic bridged metallocene, LA(R?SiR?)LBZrQ2, activated by an activator, the activator comprising aluminoxane, a modified aluminoxane, or a mixture thereof, and supported by a support, where: LA and LB are independently an unsubstituted or a substituted cyclopentadienyl ligand bonded to Zr and defined by the formula (C5H4-dRd), where R is hydrogen, a hydrocarbyl substituent, a substituted hydrocarbyl substituent, or a heteroatom substituent, and where d is 0, 1, 2, 3 or 4; LA and LB are connected to one another with a cyclic silicon bridge, R?SiR?, where R? are independently hydrocarbyl or substituted hydrocarbyl substituents that are connected with each other to form a silacycle ring; and each Q is a labile hydrocarbyl or a substituted hydrocarbyl ligand.

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: Disclosed herein is a polyolefin polymer having improved properties wherein the polymer is produced using a chromium based catalyst in combination with aluminum alkyl activators and co-catalysts. Also disclosed is a pipe comprising the inventive polymer and a film comprising the inventive polymer, each having improved properties over those known in the art.