Abstract: A catalyst system obtainable with a process comprising the following steps: i) contacting a group 4 metal compound of formula (I) MX4??(I) wherein M is a metal of group 4 of the periodic table of the element, and X is a halogen atom or an organic radical; with a compound of formula (II) ii) adding to the reaction mixture of step i) one or more boron compounds having Lewis acidity wherein the molar ratio between the boron compound and the compound of formula (I) ranges from 0.9 to 100; iii) adding the reaction mixture obtained in step ii) to a silica support. with the proviso that the catalyst system is not treated with alumoxanes.

Abstract: A catalyst system obtainable with a process comprising the following steps: i) contacting a Zirconium compound of formula (I) ZrX4??(I) wherein X, equal to or different from each other, is a halogen atom, a R, OR, SR, NR2 or PR2 group wherein R is a linear or branched, cyclic or acyclic, C1-C40-alkyl, C2-C40 alkenyl, C2-C40 alkynyl, C6-C40-aryl, C7-C40-alkylaryl or C7-C40-arylalkyl radical; or two X groups can be joined together to form a divalent R? group wherein R? is a C1-C20-alkylidene, C6-C20-arylidene, C7-C20-alkylarylidene, or C7-C20-arylalkylidene divalent radical optionally containing heteroatoms belonging to groups 13-17 of the Periodic Table of the Elements; with one or more boron compounds having Lewis acidity wherein the molar ratio between the boron compound and the compound of formula (I) ranges from 0.9 to 100; ii) adding the reaction mixture obtained in step i) to a support.

Abstract: A method of preparing supported catalysts useful for olefin polymerization is described. The catalysts comprise a Group 4 metal complex that incorporates a tridentate dianionic ligand. An activator mixture is first made from a boron compound having Lewis acidity and an excess of an alumoxane. The activator mixture is then combined with a support and the Group 4 metal complex to give a supported catalyst. The method provides an active, supported catalyst capable of making high-molecular-weight polyolefins.

Abstract: A method for preparing a supported catalyst suitable for use in slurry and gas-phase olefin polymerizations is disclosed. An alumoxane-treated silica is combined with a monocyclopentadienyl Group 6 metal complex that comprises a chelating Cp moiety to give the supported catalyst. The method is simple to practice and provides catalysts having high activity. Polyolefins made using the catalysts have high molecular weight that is readily controlled by adding hydrogen.

Abstract: A method of preparing supported catalysts useful for olefin polymerization is described. The catalysts comprise a Group 4 metal complex that incorporates a tridentate dianionic ligand. An activator mixture is first made from a boron compound having Lewis acidity and an excess of an alumoxane. The activator mixture is then combined with a support and the Group 4 metal complex to give a supported catalyst. The method provides an active, supported catalyst capable of making high-molecular-weight polyolefins.

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: Olefin polymerization in the presence of heterogeneous supported catalysts is improved by incorporating into the supported catalyst a unifunctional hydrophobic tether comprising a hydrophobic portion containing no basic nitrogen and a univalent reactive group. The unifunctional hydrophobic tether reduces fouling and sheeting in gas phase polymerization processes and improves polymer morphology and bulk density in slurry polymerization processes, while substantially maintaining or enhancing catalyst polymerization activity.

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: 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: Olefin polymerization in the presence of heterogeneous supported catalysts is improved by incorporating into the supported catalyst a unifunctional hydrophobic tether comprising a hydrophobic portion containing no basic nitrogen and a univalent reactive group. The unifunctional hydrophobic tether reduces fouling and sheeting in gas phase polymerization processes and improves polymer morphology and bulk density in slurry polymerization processes, while substantially maintaining or enhancing catalyst polymerization activity.

Abstract: A single-site olefin polymerization catalyst is described. The catalyst comprises an activator and an inorganic compound comprising iron and a tridentate N-(2-ethylamino)-2-pyridylmethanimino or N,N-bis(2-pyridylmethyl)amino ligand. The late transition metal catalyst is active in olefin polymerization.

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: A single-site olefin polymerization catalyst is described. The catalyst comprises an activator and an inorganic compound comprising iron and a tridentate N-(2-ethylamino)-2-pyridylmethanimino or N,N-bis(2-pyridylmethyl)amino ligand. The late transition metal catalyst is active in olefin polymerization.

Abstract: A catalyst system useful for polymerizing olefins is disclosed. The catalyst system comprises an activator and a complex that incorporates a Group 3 to 10 transition metal and at least one chelating dianionic bis(allyl) or bis(benzyl) ligand. The ligands are often easy to make, and they are readily incorporated into transition metal complexes. By modifying the structure of the dianionic ligand, polyolefin makers can control comonomer incorporation, catalyst activity, and polymer properties.

Abstract: A catalyst system useful for polymerizing olefins is disclosed. The catalyst system comprises an activator and a complex that incorporates a Group 3 to 10 transition metal and at least one chelating dianionic bis(allyl) or bis(benzyl) ligand. The ligands are often easy to make, and they are readily incorporated into transition metal complexes. By modifying the structure of the dianionic ligand, polyolefin makers can control comonomer incorporation, catalyst activity, and polymer properties.

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.