Abstract: A process for making an ethylene homopolymer in the presence of an oxide-supported chromium catalyst is disclosed. A small amount of an ?-olefin contacted with the catalyst before polymerizing ethylene or introduced into an ethylene homopolymerization unexpectedly boosts process productivity. When used at part per million levels, the ?-olefin improves productivity while maintaining desirable polymer properties. The invention is particularly valuable for making HDPE resins useful for blow molding applications.

Abstract: A high-temperature solution process for making an ethylene polymer blend having a controlled degree of long-chain branching is disclosed. Ethylene is polymerized in the presence of a first Ziegler-Natta catalyst comprising titanium, magnesium, and aluminum in the absence of hydrogen to produce a first ethylene polymer component having substantial long-chain branching. A second ethylene polymer component having little or no long-chain branching is also prepared. Both polymerizations are performed at a temperature from 140° C. to 250° C. The first and second ethylene polymer components are combined to give a polymer blend. The degree of long-chain branching in the blend is controlled by adjusting the relative amounts of the first and second ethylene polymer components. The invention enables the preparation of valuable products having a pre-determined degree of long-chain branching using readily available Zeigler-Natta catalysts, commercially practiced techniques, and conventional equipment.

Abstract: Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a Group 4 metal complex that incorporates a dianionic, tridentate 2-aryl-8-anilinoquinoline ligand. In one aspect, supported catalysts are prepared by first combining a boron compound having Lewis acidity with excess alumoxane to produce an activator mixture, followed by combining the activator mixture with a support and the tridentate, dianionic Group 4 metal complex. The catalysts are easy to synthesize, support, and activate, and they enable facile production of high-molecular-weight polyolefins.

Abstract: A process for making an ethylene homopolymer in the presence of an oxide-supported chromium catalyst is disclosed. A small amount of an ?-olefin contacted with the catalyst before polymerizing ethylene or introduced into an ethylene homopolymerization unexpectedly boosts process productivity. When used at part per million levels, the ?-olefin improves productivity while maintaining desirable polymer properties. The invention is particularly valuable for making HDPE resins useful for blow molding applications.

Abstract: A multi-reactor solution process for polymerizing ethylene is disclosed. Ethylene is polymerized in a first reaction zone in two parallel reactors and the polyethylene is transferred to a second reaction zone to continue or complete the polymerization. Ethylene is contacted with a mixture of a titanium halide and a vanadium halide in the first parallel reactor and with a magnesium-titanium based Ziegler-Natta catalyst at a lower temperature in the second parallel reactor. The process gives improved catalyst activity.

Abstract: A process for the copolymerization of ethylene and ?-olefins which utilizes a mixed modifier comprised of a conjugated diene and alkoxysilane is disclosed.

Abstract: A process to prepare a multimodal polyethylene with controlled LCB distribution is disclosed. In the first stage, ethylene is polymerized in the presence of a Ziegler catalyst that results in a homopolyethylene component having a higher LCB concentration. In the second stage, ethylene is copolymerized with a 1-olefin in the presence of the Ziegler catalyst and a lower concentration of hydrogen resulting in a copolymer component with a lower LCB concentration. The homopolyethylene component and the copolymer component are combined to form a novel multimodal polyethylene.

Abstract: A process for preparing a polyethylene in a multi-stage process is described. The process comprises pre-treating a Ziegler catalyst in a first stage in the presence of a 1-olefin/ethylene mixture or a 1-olefin to produce a LLDPE or VLDPE, which have the characteristics of a polymer prepared with a single-site catalyst, e.g. high levels of short-chain branching that are uniformly distributed. The contents of the first stage are then transferred to a second stage where an ethylene or an ethylene/1-olefin mixture is polymerized in the presence of the pre-treated catalyst to form a polyethylene with good processability.

Abstract: This invention is a method of purifying fuels containing organosulfur impurities. The fuel is oxidized with an organic hydroperoxide in the presence of an oxidation catalyst to form a sulfone product, followed by extraction of the sulfone product by solid-liquid or liquid-liquid extraction. The fuel is then contacted with a decomposition catalyst to remove the residual organic hydroperoxide from the fuel.

Abstract: Resins comprising a relatively high-density, low-molecular-weight polyethylene component and a relatively low-density, high-molecular-weight ethylene copolymer component and methods of making the resins are disclosed. The rheological polydispersity of the high-density component exceeds that of either the resin or the low-density component. The resins are valuable for making films, sheets, coatings, pipes, fibers, and molded articles having a favorable balance of good stiffness and excellent environmental stress crack resistance.

Abstract: Single-site catalyst systems useful for polymerizing olefins are disclosed. The catalyst systems comprise an organometallic complex and an activator. The complex includes a Group 3-10 transition metal, M, and at least one indenoindolyl ligand that is pi-bonded to M. The activator is a reaction product of an alkylaluminum compound and an organoboronic acid. Catalyst systems of the invention significantly outperform known catalyst systems that employ a metallocene complex and similar aluminoboronate activators.

Abstract: A method for making ethylene polymers and copolymers is disclosed. The method uses a catalyst system comprising a low level of an aluminum-containing activator, a bridged indenoindolyl transition metal complex, and a treated silica support. The method enables economical preparation of ethylene copolymers having very low density. The silica-supported, bridged complexes incorporate comonomers efficiently and are valuable for a commercial slurry loop process. Use of a bridged indeno[2,1-b]indolyl complex provides exceptionally efficient comonomer incorporation, and gives polymers with a substantial and controlled level of long-chain branching. The method facilitates the production of a wide variety of polyolefins, from HDPE to plastomers.

Abstract: The present invention provides a method of forming a polyolefin resin having a relatively high densities and a long chain branch index (“LCB”) greater than about 1. The method of the invention comprises forming a reaction mixture by combining molecular hydrogen, a first olefin, an optional second olefin, a diluent, and a vanadium-containing catalyst system at a sufficient temperature to allow formation of the polyolefin resin and initiating polymerization of the reaction mixture.

Abstract: A process for preparing premixed supported boraaryl catalysts having improved shelf life is provided. The process comprises supporting an organometallic compound comprising a group 3-10 transition metal or lanthanide metal and at least one boraaryl ligand an inorganic support which has been chemically and thermally dehydroxylated to remove all hydroxyl from the surface of the support; contacting with an organoaluminum compound utilizing an incipient wetness procedure wherein 90 to 150 percent of the catalyst pore volume is filled with a hydrocarbon solution containing the organoaluminum and provide a molar ratio of aluminum to transition/lanthanide metal of 0.5:1 to 50:1; and recovering the premixed catalyst powder.

Abstract: Single-site catalyst systems useful for polymerizing olefins are disclosed. The catalyst systems comprise an organometallic complex and an activator. The complex includes a Group 3-10 transition metal, M, and at least one indenoindolyl ligand that is pi-bonded to M. The activator is a reaction product of an alkylaluminum compound and an organoboronic acid. Catalyst systems of the invention significantly outperform known catalyst-systems that employ a metallocene complex and similar aluminoboronate activators.

Abstract: Prealkylation of a supported catalyst system comprising a transition metal or inner transition metal complex precatalyst and a bulky, non-coordinating anion on an inorganic support by treatment with a solution of metal alkyl in a ratio of metal of metal alkyl to transition metal or inner transition metal of precatalyst less than 20:1, and in an amount of solution insufficient to form a paste or dispersion provides supported catalysts of high olefin polymerization activity which promote production of polyolefins of low polydispersity and improved morphology.

Abstract: Single-site catalyst systems useful for polymerizing olefins are disclosed. The catalyst systems comprise an organometallic complex and an activator. The complex includes a Group 3-10 transition metal, M, and at least one indenoindolyl ligand that is pi-bonded to M. The activator is a reaction product of an alkylaluminum compound and an organoboronic acid. Catalyst systems of the invention significantly outperform known catalyst systems that employ a metallocene complex and similar aluminoboronate activators.

Abstract: A slurry ethylene polymerization process is disclosed. The process uses an unsupported late transition metal catalyst that comprises an acenaphthene N,N′-bis(arylimine) ligand. The process is conducted in the presence of a non-aromatic hydrocarbon diluent. The process produces polyethylene having high molecular weight in powder form and it gives high catalyst activity at relatively high temperatures.

Abstract: Prealkylation of a supported catalyst system comprising a transition metal or inner transition metal complex precatalyst and a bulky, non-coordinating anion on an inorganic support by treatment with a solution of metal alkyl in a ratio of metal of metal alkyl to transition metal or inner transition metal of precatalyst less than 20:1, and in an amount of solution insufficient to form a paste or dispersion provides supported catalysts of high olefin polymerization activity which promote production of polyolefins of low polydispersity and improved morphology.

Abstract: A method for making ethylene polymers and copolymers is disclosed. The method uses a catalyst system comprising a low level of an aluminum-containing activator, a bridged indenoindolyl transition metal complex, and a treated silica support. The method enables economical preparation of ethylene copolymers having very low density. The silica-supported, bridged complexes incorporate comonomers efficiently and are valuable for a commercial slurry loop process. Use of a bridged indeno[2,1-b]indolyl complex provides exceptionally efficient comonomer incorporation, and gives polymers with a substantial and controlled level of long-chain branching. The method facilitates the production of a wide variety of polyolefins, from HDPE to plastomers.