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: 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: A film comprising a polyethylene composition, the polyethylene composition in one embodiment comprising a high molecular weight component having a weight average molecular weight of greater than 50,000 amu and a low molecular weight component having a weight average molecular weight of less than 50,000 amu; the polyethylene composition possessing a density of between 0.940 and 0.970 g/cm3, and an I21 value of less than 20 dg/min; characterized in that the polyethylene composition extrudes at an advantageously high specific throughput at an advantageously low melt temperature, and wherein the film has a gel count of less than 100.

Abstract: A film comprising a polyethylene composition, the polyethylene composition in one embodiment comprising a high molecular weight component having a weight average molecular weight of greater than 50,000 amu and a low molecular weight component having a weight average molecular weight of less than 50,000 amu; the polyethylene composition possessing a density of between 0.940 and 0.970 g/cm3, and an I21 value of less than 20 dg/min; characterized in that the polyethylene composition extrudes at an advantageously high specific throughput at an advantageously low melt temperature, and wherein the film has a gel count of less than 100.

Abstract: A process of producing a bimodal polyolefin composition is described, which includes in one embodiment contacting monomers with a supported bimetallic catalyst composition for a time sufficient to form a bimodal polyolefin composition that includes a high molecular weight polyolefin component and a low molecular weight polyolefin component; wherein the supported bimetallic catalyst includes a first catalyst component that is preferably non-metallocene, and a second catalyst component that includes a metallocene catalyst compound having at least one fluoride or fluorine containing leaving group, wherein the bimetallic catalyst is supported by an enhanced silica, dehydrated at a temperature of 800° C. or more in one embodiment.

Abstract: A film comprising a polyethylene composition, the polyethylene composition in one embodiment comprising a high molecular weight component having a weight average molecular weight of greater than 50,000 amu and a low molecular weight component having a weight average molecular weight of less than 50,000 amu; the polyethylene composition possessing a density of between 0.940 and 0.970 g/cm3, and an I21 value of less than 20 dg/min; characterized in that the polyethylene composition extrudes at an advantageously high specific throughput at an advantageously low melt temperature, and wherein the film has a gel count of less than 100.

Abstract: A process of producing a bimodal polyolefin composition is described, which includes in one embodiment contacting monomers with a supported bimetallic catalyst composition for a time sufficient to form a bimodal polyolefin composition that includes a high molecular weight polyolefin component and a low molecular weight polyolefin component; wherein the supported bimetallic catalyst includes a first catalyst component that is preferably non-metallocene, and a second catalyst component that includes a metallocene catalyst compound having at least one fluoride or fluorine containing leaving group, wherein the bimetallic catalyst is supported by an enhanced silica, dehydrated at a temperature of 800° C. or more in one embodiment.

Abstract: A process of transitioning from a first polymerization reaction conducted in the presence of a mixed catalyst system to a second polymerization reaction conducted in the presence of a chrome-based catalyst system is disclosed, the polymerization reactions being conducted in one embodiment in a polymerization zone of a gas phase fluidized bed reactor which contains a fluidized bed of polymer particles by the essentially continuous passage of monomer gases through the polymerization zone, comprising: a) discontinuing the introduction of the mixed catalyst system into the reactor; b) maintaining polymerization conditions in the reactor and permitting polymerization to continue for a period of time to allow the components of the mixed catalyst system present in the reactor to produce additional polymer particles; c) introducing a deactivating agent into the fluidized bed in an amount sufficient to deactivate the mixed catalyst system; d) establishing optimal conditions within the reactor for the chrome-based

Abstract: A method of transitioning catalysts for polyolefin polymerization is provided. In one aspect, the process includes providing a polymerization reactor that includes a first catalyst system, contacting olefin monomers with the first catalyst system to form polyolefin in a first polymerization reaction and introducing a catalyst killer to the polymerization reactor in an amount sufficient to terminate the first polymerization reaction. The method further includes introducing a second catalyst system to the polymerization reactor in the presence of at least a portion of the catalyst killer, wherein the at least a portion of the catalyst killer is an amount sufficient to activate the second catalyst system and contacting olefin monomers with the second catalyst system to form polyolefin in a second polymerization reaction.

Abstract: A process of transitioning from a first polymerization reaction conducted in the presence of a mixed catalyst system comprising to a second polymerization reaction conducted in the presence of a chrome-based catalyst system is disclosed, the polymerization reactions being conducted in one embodiment in a polymerization zone of a gas phase fluidized bed reactor which contains a fluidized bed of polymer particles by the essentially continuous passage of monomer gases through the polymerization zone, comprising:

Abstract: A method of transitioning catalysts for polyolefin polymerization is provided. In one aspect, the process includes providing a polymerization reactor that includes a first catalyst system, contacting olefin monomers with the first catalyst system to form polyolefin in a first polymerization reaction and introducing a catalyst killer to the polymerization reactor in an amount sufficient to terminate the first polymerization reaction. The method further includes introducing a second catalyst system to the polymerization reactor in the presence of at least a portion of the catalyst killer, wherein the at least a portion of the catalyst killer is an amount sufficient to activate the second catalyst system and contacting olefin monomers with the second catalyst system to form polyolefin in a second polymerization reaction.

Abstract: A gas phase polymerization process for producing a polyolefin composition is described, which includes passing a gaseous stream containing hydrogen gas and one or more monomers, including ethylene monomers, through a reactor that includes a fluidized bed, under reactive conditions, in the presence of a catalyst that includes metallocene, to provide a polyolefin composition, wherein in one embodiment the fluidized bulk density is 60% or more of the settled bulk density (or, a voidage of 40% or less); and wherein the voidage is controlled by a number of factors including, in certain embodiments, (a) the reactor temperature being maintained at 100° C. or below; (b) the molar ratio of hydrogen gas to ethylene introduced into the reactor being 0.015 or below.

Abstract: A process of producing a bimodal polyolefin composition is described, which includes in one embodiment contacting monomers with a supported bimetallic catalyst composition for a time sufficient to form a bimodal polyolefin composition that includes a high molecular weight polyolefin component and a low molecular weight polyolefin component; wherein the supported bimetallic catalyst includes a first catalyst component that is preferably non-metallocene, and a second catalyst component that includes a metallocene catalyst compound having at least one fluoride or fluorine containing leaving group, wherein the bimetallic catalyst is supported by an enhanced silica, dehydrated at a temperature of 800° C. or more in one embodiment.

Abstract: A gas phase polymerization process for producing a polyolefin composition is described, which includes passing a gaseous stream containing hydrogen gas and one or more monomers, including ethylene monomers, through a reactor that includes a fluidized bed, under reactive conditions, in the presence of a catalyst that includes metallocene, to provide a polyolefin composition, wherein in one embodiment the fluidized bulk density is 60% or more of the settled bulk density (or, a voidage of 40% or less); and wherein the voidage is controlled by a number of factors including, in certain embodiments, (a) the reactor temperature being maintained at 100° C. or below; (b) the molar ratio of hydrogen gas to ethylene introduced into the reactor being 0.015 or below.