Abstract: A nucleating agent-free and LLDPE-free polyolefin composition for making films with enhanced barrier properties against water vapor and oxygen gas. Related aspects include formulations, manufactured articles, films, and methods.

Abstract: Embodiments of the present disclosure relate to a method of preparing polyethylene compositions comprising polymerizing ethylene in a first gas-phase reactor and polymerizing ethylene in a second gas-phase reactor in the presence of hydrogen; wherein at least one of the first or second gas-phase reactors comprises a first and second polymerization zone; wherein a hydrogen pressure of the first and second polymerization zones are different such that at least a portion of the second ethylene cycles through the first and second polymerization zones and a gas mixture of each polymerization zone is partially or totally prevented from entering the other zone.

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: 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: Provided is an ethylene-?-olefin-nonconjugated polyene copolymer having ethylene units, ?-olefin units and nonconjugated polyene units, wherein the copolymer satisfies the following requirements: (A): the intrinsic viscosity [?] is 0.5 to 1.8 dl/g, (B): the content of ethylene units is 50 to 90 mol % and the content of ?-olefin units is 50 to 10 mol % where the sum total of the contents of ethylene units and ?-olefin units is taken as 100 mol %, (C): the iodine value is 1 to 50, (D): the ratio of tan ? taken at 100° C. and 2 cpm to tan ? taken at 100° C. and 1000 cpm is from 1.0 to 1.7, and (E): the ratio of the Z-average molecular weight to the number average molecular weight is from 15 to 25 and the weight average molecular weight to the number average molecular weight is from 3 to 5.

Abstract: A process and the resultant product from the process for continuously making an EPDM utilizing ethylene, propylene, and dienes. This process allows for the creation of products with high diene contents and broad molecular weight distributions while utilizing a continuous flow reactor and a known catalyst. The process allows for these products to be made without gelling, or fouling of the reactor, which are problems known in the art.

Abstract: A process for continuously making a terpolymer or a tetrapolymer utilizing ethylene, an alpha olefin, and at least one polyene. This process allows for the creation of products with high polyene contents and broad molecular weight distributions while utilizing a continuous flow reactor and a known catalyst. The process allows for these products to be made without gelling, or fouling of the reactor.

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 invention is directed to a metallocene catalyst system and a process for preparing the system. The metallocene catalyst system comprises a support and metallocene bound substantially throughout the support. The selection of certain supports facilitates the production of metallocene catalyst systems having increased catalytic activity than previously recognized.

Abstract: The present invention relates to a method for producing a catalyst slurry blend suitable for polymerizing ethylene in an ethylene polymerization loop reactor for obtaining an at least trimodal polyethylene product, comprising the steps of: transferring a first ethylene polymerization catalyst at a first mass flow rate to a mixing vessel, simultaneously transferring a second ethylene polymerization catalyst at a second mass flow rate to said mixing vessel, thereby in situ providing a catalyst slurry blend, wherein said second ethylene polymerization catalyst is different from the first ethylene polymerization catalyst, adjusting and monitoring said first and second mass flow rates, thereby obtaining said catalyst slurry blend at a concentration suitable for polymerizing ethylene, and feeding said catalyst slurry blend to an ethylene polymerization double loop reactor producing said at least trimodal polyethylene product.

Abstract: Methods for controlling properties of an olefin polymer using an organozinc compound are disclosed. The HLMI/MI shear ratio of the polymer can be decreased and the Mz/Mw ratio of the polymer can be increased via the addition of the organozinc compound.

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: 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: Group 4 metal complexes comprising a polyvalent, heteroaryl donor ligand and their use as components of olefin polymerization catalysts, especially suited for preparing propylene/ethylene copolymer products having high isotacticity and low molecular weight, are disclosed.

Abstract: The invention is directed to a metallocene catalyst system comprising an inert silica support having pores with a peak pore volume of greater than about 0.115 mL/g at a pore diameter between about 250 Angstroms and about 350 Angstroms, and an alumoxane activator, with the metallocene being bound substantially throughout the support. The activator is grafted to the support in a solvent at a reflux temperature of toluene to obtain an aluminoxane on silica, and a metallocene component is added to make a MCS having a metallocene loading of about 2 wt %. This facilitates the production of metallocene catalyst systems having increased catalytic activity than previously recognized that is at least about 20 percent higher than the catalytic activity for a metallocene loading of about 1 wt % where the activator is grafted to the support at room temperature.

Abstract: A highly active supported chromium catalyst composition for ethylene and other olefins polymerization and also for ethylene copolymerization with efficient incorporation of comonomer, produces polymers with superior spherical morphology, improved bulk density and almost 0% fines. The catalyst composition component includes at least one chromium compound, mainly chromium acetylacetonate, or chromium hexaflouroacetonylacetonate, or chromium diethylmalonate. One magnesium compound, or aluminum compound, metal alkoxy compound and defined polymer particles mainly chloromethylated cross linked styrene-DVB copolymer or polyvinylchloride. The catalyst composition, when used in conjunction with an organoaluminum compound or a mixture of organoaluminum compounds, can be used for olefin polymerization to produce medium or high density polyethylene and copolymers of ethylene with alpha-olefins having about 3 to 18 carbon atoms.

Abstract: A catalyst composition comprising a zirconium complex of a polyvalent aryloxyether and an alumoxane, polymerization processes employing the same, especially the continuous, solution polymerization of ethylene and one or more C3-30 olefins or diolefins to prepare copolymers having reduced cocatalyst by-product content, are disclosed.

Abstract: A method for preparing a reactor for performance of a polymerization reaction, the method including providing at least one seed bed into the reactor; wherein the at least one seed bed includes at least one organometallic compound and polymer particles.

Abstract: Group 4 metal complexes comprising a polyvalent, heteroaryl donor ligand and their use as components of olefin polymerization catalysts, especially suited for preparing propylene/ethylene copolymer products having high isotacticity and low molecular weight, are disclosed.

Abstract: The present invention provides a polymerization process which is conducted by contacting an olefin monomer and at least one olefin comonomer in the presence of hydrogen and a metallocene-based catalyst composition. Polymers produced from the polymerization process are also provided, and these polymers have a reverse comonomer distribution, low levels of long chain branches, and a ratio of Mw/Mn from about 3 to about 6.

Abstract: Disclosed herein are various methods and systems for gas and liquid phase polymer production. In certain embodiments, the methods comprise manipulating properties of polymers produced by adjusting the hydrogen feed rate.

Abstract: The purpose of the present invention is provite a process for producing an olefin polymer, which can produce an olefin polymer having a higher molecular weight even in the presence of hydrogen and can obtain an olefin polymer having good powder characteristics by lowering hydrogen concentration efficiently in polymerizing an olefin in the presence of hydrogen by use of a gas phase reaction vessel. There is provided a process for producing an olefin polymer comprising the steps of: using a gas phase reaction vessel; polymerizing an olefin by use of a catalyst for olefin polymerization in the presence of hydrogen; adding a hydrogenation catalyst into the gas phase reaction vessel; and adding a polymerization activity depressant.

Abstract: The purpose of the present invention is to provide a process for producing an olefin polymer, which can produce an olefin polymer having a higher molecular weight by lowering hydrogen concentration efficiently in polymerizing an olefin in the presence of hydrogen by use of a gas phase reaction vessel. There is provided a process for producing an olefin polymer comprising the steps of: using a gas phase reaction vessel; polymerizing an olefin by use of a catalyst for olefin polymerization in the presence of hydrogen; and adding a hydrogenation catalyst to a bed portion in the gas phase reaction vessel.

Abstract: A method of polymerizing poly(cyclic)olefin monomers encompassing (a) combining a monomer composition containing the poly(cyclic)olefin monomers, a non-olefinic chain transfer agent and an activator compound to faun a mixture; (b) heating the mixture; and (c) adding a polymerization catalyst containing Ni and/or Pd. The non-olefinic chain transfer agent includes one or more compounds selected from H2, alkylsilanes, alkylalkoxysilanes, alkylgermanes, alkylalkoxygermanes, alkylstannanes, and alkylalkoxystannanes. The activator is characterized as having an active hydrogen with a pKa of at least 5. The resulting poly(cyclic)olefin polymers can be used in photoresist compositions.

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: High durable polarized film comprising a radiation curable PSA layer for lamination in TFT/LCD applications have high humidity and heat resistance. In one embodiment, the adhesive comprises a UV curable acrylic polymer, a compatible tackifier, a multifunction unsaturated oligomer, and a long chain alkyl acrylate monomer.

Abstract: One exemplary method for message suppression comprises: providing first and second rules, each having one or more preconditions and a conclusion, wherein the first rule also has a suppressed-by attribute and at least one of the second preconditions is suppressing; evaluating the one or more first and second preconditions; identifying the first rule as true or false; displaying the message of the second rule if all of the second preconditions are met; identifying the first rule as suppressed if the second rule is named in the suppressed-by attribute; and inhibiting the message display of the suppressed rule or routing the message to second display. The system can comprise: a database containing knowledge of the production unit; a user interface, and at least one precondition, a suppressed by attribute, and one or more rules each having a conclusion and at least one suppressing precondition; an inference engine; and a display.

Abstract: A synthesis process of trans-1,4-polyisoprene, using bulk precipitation polymerization of isoprene catalyzed by supported titanium catalyst TiCl4/MgCl2. The process includes prepolymerizing carried out in a prepolymerization reactor with an anchor agitator; polymerizing carried out in a polymerization reactor with a helical ribbon agitator; and devolatilizing and drying carried out in a vacuum rake dryer. Not only does the process require lower energy consumption and thus a lower production cost, but it also eliminates the emission of three wastes.

Abstract: A method of polymerizing poly(cyclic)olefin monomers encompassing (a) combining a monomer composition containing the poly(cyclic)olefin monomers, a non-olefinic chain transfer agent and an activator compound to form a mixture; (b) heating the mixture; and (c) adding a polymerization catalyst containing Ni and/or Pd. The non-olefinic chain transfer agent includes one or more compounds selected from H2, alkylsilanes, alkylalkoxysilanes, alkylgermanes, alkylalkoxygermanes, alkylstannanes, and alkylalkoxystannanes. The activator is characterized as having an active hydrogen with a pKa of at least 5. The resulting poly(cyclic)olefin polymers can be used in photoresist compositions.

Abstract: A process for the polymerisation of ethylene and optionally at least one C3-20 alpha olefin comonomer in the slurry or solution phase in a reactor having a polymer outlet stream, a procatalyst or catalyst feed stream and a hydrogen feed stream, said polymerisation being effected in the presence of a metallocene catalyst, a diluent and hydrogen, wherein said diluent is recycled from said outlet stream to said hydrogen feed stream, said procatalyst or catalyst feed stream is free of hydrogen, said hydrogen feed stream is free of procatalyst or catalyst and said procatalyst or catalyst feed stream does not comprise recycled diluent.

Abstract: A slurry process for polymerizing ethylene is disclosed. The process comprises polymerizing ethylene in the presence of an ?-olefin and a catalyst comprising an activator and a supported bridged indeno[1,2-b]indolyl zirconium complex. The process produces polyethylene characterized by good incorporation of the ?-olefin and moderate long-chain branching. The process is capable of forming high molecular weight polyethylene and has good catalyst activity.

Abstract: A process for polymerizing ethylene is disclosed. The polymerization is performed in the presence of a Ziegler-Natta catalyst system in two slurry reaction zones. Most of the polyethylene (70-95 wt. %) is produced in one of the zones, while a smaller fraction is produced in the other zone. The ratio of the weight average molecular weight of the smaller fraction to that of the larger fraction is greater than 8:1. The resulting polyethylene blend, which should have both high melt strength and high extrudate swell, will be useful for blow-molding applications.

Abstract: Process for preparing a broad molecular weight polyethylene by polymerizing ethylene in the presence of a polymerization catalyst, the process comprising the following steps, in any mutual order: a) polymerizing ethylene, optionally together with one or more ?-olefinic comonomers having from 3 to 12 carbon atoms, in a gas-phase reactor in the presence of hydrogen, b) copolymerizing ethylene with one or more ?-olefinic comonomers having from 3 to 12 carbon atoms in another gas-phase reactor in the presence of an amount of hydrogen less than step a), where in at least one of said gas-phase reactors the growing polymer particles flow upward through a first polymerization zone under fast fluidization or transport conditions, leave said first polymerization zone and enter a second polymerization zone through which they flow downward under the action of gravity.

Abstract: Processes for reducing the ultra high molecular weight polymeric material content of a high density polyethylene produced with a bis-triarylsilyl chromate catalyst system are provided. Processes for reducing the gel content of articles produced from high density polyethylene are also provided. The gel content of the articles is reduced by using the high density polyethylene with reduced ultra high molecular weight polymeric material content to produce the articles. The processes described reduce the content of ultra high molecular weight polymeric material in comparison to conventional high density polyethylene by introducing at least one catalyst deactivator into a recycle gas line containing a recycle gas stream associated with the fluidized bed reactor. The at least one catalyst deactivator has a boiling point lower than the maximum temperature within the recycle gas line.

Abstract: Olefin polymer composition comprising (by weight, unless otherwise specified): A) 60-95% of a propylene homopolymer or copoloymer having a Polydispersity Index (P.I.) value of from 4.6 to 10 and a content of isotactic pentads (mmmm), measured by 13C NMR on the fraction insoluble in xylene at 25° C., higher than 98 molar, B) 5-40% of a copolymer of ethylene containing from 40% to 70% of propylene or C4-C10 ?-olefins) or of combinations thereof, and optionally minor proportions of a diene; said composition having a Temperature Rising Elution Fractionation (TREF) profile, obtained by fractionation in xylene and collection of fractions at temperatures of 40° C., 80° C. and 90° C., in which the ethylene content Y of the fraction collected at 90° C. satisfies the following relation (1): Y??0.8+0.035X+0.0091X2 wherein X is the ethylene content of the fraction collected at 40° C. and both X and Y are expressed in percent by weight, and a value of intrinsic viscosity [?] of the fraction soluble in xylene at 25° C.

Abstract: An ethylene polymerization process is disclosed. Ethylene is polymerized in two slurry reaction zones with a C6-C10 alpha-olefin in the presence of a single-site catalyst capable of making a high molecular weight polyolefin. The process yields medium density and linear low density polyethylene having a bimodal molecular weight distribution and a melt index from about 0.10 to about 0.80. Films from the polyethylene have superior impact properties.

Abstract: A method for controlling the flowability of polymer particles flowing downward in a densified form inside a polymerization reactor, in which one or more monomers are gas-phase polymerized in the presence of a polymerization catalyst, the density of solid (Kg of polymer per m3 of reactor occupied by the polymer) being higher than 80% of the “poured bulk density” of the polymer, the method being characterized in that a liquid stream is continuously fed into the polymerization reactor at a mass flow rate per unity of reactor surface higher than 30 Kg/h m2.

Abstract: Processes for preparing substantially linear polymers from diisopropenylbenzenes are provided. The polymers are useful in making a variety of products, including coatings, pigment dispersing agents, and stabilizers.

Abstract: Multimodal polyolefin polymers may be prepared in series-connected polymerization reactors where a prior reactor is a slurry reactor employing light solvent as the slurry medium and hydrogen to limit polymer molecular weight, the polymer product from the prior reactor being substantially freed of hydrogen prior to entry into a subsequent polymerization reactor operating at low hydrogen pressure to produce a high molecular weight olefin. The economics and operating performance of such a series slurry reactor polyethylene process can be significantly improved through the use of an intermediate slurry transfer system and hydrogen removal apparatus that employs flash drums in series in conjunction with a warm recycle solvent slurry diluent.

Abstract: Disclosed is a process for the preparation of a high stereospecific (isotactic) polybutylene polymer comprising the step of polymerizing a reactive monomer, 1-butene, which is used or is not used as a solvent, in the presence of catalyst and inert gas. According to the present invention, it is possible to prepare a high stereospecific polybutylene polymer in much higher activity than that of any other known processes for the preparation of a high stereospecific polybutylene polymer. The high stereospecific polybutylene polymer according to the present invention is a homopolymer of 1-butene, or a copolymer containing a-olefin and up to 40% by weight of a comonomer, wherein titanium in the catalyst residues is not detected in the ppm level, stereospecificity (Isotactic Index, mmmm %) determined by 13C-NMR is 96 or more, molecular weight distribution (Mw/Mn) is 3-6, and molecular weight distribution (Mw/Mn) can be controlled to 8 or more.

Abstract: Properties of a polymer produced in gas phase or slurry phase using a dual catalyst such as polydispersity and comonomer incorporation, may be controlled by controlling reaction parameters such as temperature, (co)monomer pressure, hydrogen partial pressure and the presence of non-polymerizable hydrocarbon. This provides an easy method to control the bimodality of a polymer as well as comonomer incorporation.

Abstract: Properties of a polymer produced using a dual catalyst on the same support, such as polydispersity and comonomer incorporation, may be controlled by controlling reaction parameters such as temperature, monomer pressure, hydrogen partial pressure and the presence of non-polymerizable hydrocarbon. This provides an easy method to control the bimodality of a polymer as well as comonomer incorporation.

Abstract: A method of polymerizing olefins comprising combining in one embodiment ethylene and optionally one or more ?-olefins with a catalyst composition in a continuous polymerization reactor at a pressure of less than 10,000 kPa; wherein the catalyst composition comprises a hafnocene; and isolating a polyethylene having a density in the range of from 0.930 to 0.975 g/cm3. Also provided is a method of transitioning a continuous polymerization reactor from production of a low density polyethylene to a medium or high density polyethylene. Also provided is a medium to high density polyethylene suitable for injection or rotomolding applications. Also provided is a single catalyst composition suitable for such needs.

Abstract: Methods of controlling the flow index and/or molecular weight split of a polymer composition are disclosed. The method of producing a polymer composition in one embodiment comprises incorporating a high molecular weight polymer into a low molecular weight polymer to form the polymer composition in a single polymerization reactor in the presence of polymerizable monomers, a bimetallic catalyst composition and at least one control agent; wherein the control agent is added in an amount sufficient to control the level of incorporation of the high molecular weight polymer, the level of low molecular weight polymer, or both. Examples of control agents include alcohols, ethers, amines and oxygen.

Abstract: A method of polymerizing olefins comprising combining in one embodiment ethylene and optionally one or more ?-olefins with a catalyst composition in a continuous polymerization reactor at a pressure of less than 10,000 kPa; wherein the catalyst composition comprises a hafnocene; and isolating a polyethylene having a density in the range of from 0.930 to 0.975 g/cm3. Also provided is a method of transitioning a continuous polymerization reactor from production of a low density polyethylene to a medium or high density polyethylene. Also provided is a medium to high density polyethylene suitable for injection or rotomolding applications. Also provided is a single catalyst composition suitable for such needs.

Abstract: Methods for controlling a melt viscosity of a polyolefin, controlling comonomer distribution of a polyolefin, achieving a targeted melt viscosity of a polyolefin, and films made from such polyolefins are provided. The methods include contacting an olefin monomer and at least one comonomer with a catalyst system in the presence of a condensable fluid comprising a saturated hydrocarbon having from 2 to 8 carbon atoms. The catalyst system in one embodiment includes a hafnium metallocene catalyst component.

Abstract: A UV-transparent pressure sensitive adhesive comprising (a) a copolymer of (a1) from 75 to 99.8% by weight of acrylic esters and/or methacrylic esters of the formula CH2?CH(R1)(COOR2), where R1 is H or CH3 and R2 is an alkyl chain having 1 to 20 carbon atoms; (a2) from 0 to 10% by weight of acrylic acid and/or methacrylic acid of the formula CH2?CH(R1)(COOH), where R1 is H or CH3; (a3) from 0.2 to 5% by weight of olefinically unsaturated monomers which contain at least one UV-crosslinking functional group per monomer; and (a4) from 0 to 20% by weight of olefinically unsaturated monomers which contain at least one functional group per monomer; the copolymer having a weight average molecular weight of less than 300,000 g/mol and (b) from 2 to 20% by weight, based on the weight of copolymer, of a silicate filler, the silicate filler having a maximum particle diameter of 50 nm; and having a residual solvent fraction of less than 1%, based on the pressure sensitive adhesive.

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

Abstract: A method of polymerizing olefins comprising combining in one embodiment ethylene and optionally one or more ?-olefins with a catalyst composition in a continuous polymerization reactor at a pressure of less than 10,000 kPa; wherein the catalyst composition comprises a hafnocene; and isolating a polyethylene having a density in the range of from 0.930 to 0.975 g/cm3. Also provided is a method of transitioning a continuous polymerization reactor from production of a low density polyethylene to a medium or high density polyethylene. Also provided is a medium to high density polyethylene suitable for injection or rotomolding applications. Also provided is a single catalyst composition suitable for such needs.

Abstract: A metallocene catalyst may be temporarily and reversibly passivated by contact with an effective amount of an unsaturated hydrocarbon passivating compound.