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Showing 1 to 17 of 17 for “"ethylene polymerization"”.
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Investigations into cyclopropanation and ethylene polymerization via salicylaldiminato copper (II) complexes
… the general route toward successful copper(II) ethylene polymerization catalysts. Catalytic activity of the copper(II) complexes is very low. Polymer chain growth from a copper catalyst is very unlikely. Copper-carbon bonds decompose by homolytic cleavage or C-H activation. Copper-alkyls and …
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Synthesis of Mononuclear Transition Metal Complexes and their Applications as Catalysts for Ethylene Polymerization
… this study. Their catalytic performance towards ethylene polymerization reactions was also studied. The ligand systems mentioned above were synthesized via condensation reactions using polyphosphoric acid which acts as solvent, oxidizing and dehydration agent. The condensation reactions proceeded …
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Synthesis of Group (lV) Transition Metal Complexes and their Applications as Catalysts for Ethylene Polymerization
… their applications as catalysts in homogeneous ethylene polymerization reactions. For this purpose, different types of organic compounds and their group (IV) metal complexes were synthesized and tested for ethylene polymerization after activation with MAO. The first part of this work describes …
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Synthesis of Bridged and Unbridged Group (lV) Metallocene Complexes as Catalyst Precursors for Ethylene Polymerization
… their catalytic performance in the homogeneous polymerization of ethylene. To accomplish this goal, various ligand precursors were prepared which include 1- and 2-substituted silylindenyl compounds, 1,2-bis(inden-1-yldimethylsilyl)benzene, 2,2’-bis(inden-1-ylmethyl)-1,1’-biphenyl and …
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Divalent transition metal centers: the synthesis of new chemical vapor deposition precursors and studies of ethylene polymerization and oligomerization catalysts
… The reactivity of these complexes with ethylene when activated with an aluminum alkyl co-catalyst will be of primary focus. The N,N-dimethylaminodiboranate compounds Ti(DMADB)2, Cr(DMADB)2, and Cp*Cr(DMADB) are active ethylene polymerization catalysts in the presence of an aluminum …
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Synthesis of Electron Deficient N-heterocyclic-carbenes and Activity of Imidazol-2-imine Thioureate Ligand on Group 10 Transition Metals
… ligands that have low activity towards ethylene polymerization due to their electron rich nature. In an attempt to alleviate this an electron poor naphthalene-1,4-dione-IMes imidazol-2-imine ligand (L) was synthesized in 90% yield (14a) and coordinated to titanium (LTiCpCl2, 15). The …
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Mononuclear and Dinuclear Complexes of Allylated alpha-Diimines as Catalysts for the Polymerization of Ethylene
… active sites for the oligomerization and polymerization of alpha-olefins, especially ethylene. The plan of synthesis involves precursors consisting of a diimine moiety coordinated to a late or early transition metal and a metallocene or half sandwich moiety. In order to achieve these …
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The Versatility of Aluminum Systems: Ligand Transfer Agents and Polymerization Catalysts
… are studied in various contexts. During ethylene polymerization with LCu(II) catalysts in the presence of methylaluminoxane (MAO), ligand (L) transfer is observed from the copper centre to the aluminum centre present in MAO. In the α-diimine case, an (imino-amido)AlMe2 complex is formed …
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Early Transition Metal Complexes Stabilized by Bulky Aminopyridinato Ligands
… thermally robust, highly active and selective ethylene polymerization catalysts. Ethylene is polymerized highly selectively out of a mixture of ethylene and propylene. Slight changes in the steric demand of the bulky ligand periphery can be used to tune the nature of the formed polymers by …
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The Use of Functionalized Zirconocenes as Precursors to Silica-Supported Zirconocene Olefin Polymerization Catalysts
… to silica-supported metallocene olefin polymerization catalysts. Our first objective was to extend the metallocene "functionalization" chemistry to obtain substituents bearing more than one electrophilic bond. The reactivities of Me3Sn and Ph2MeSi substituents were explored in detail. …
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NEW TRANSITION METAL CATALYSTS FOR CARBON-CARBON BOND FORMATION
… was demonstrated. To demonstrate this effect the ethylene polymerization activity of a salicyliminato nickel catalyst substituted with the powerfully electron-withdrawing 2,4,6- triphenylpyridinium (trippy) group was juxtaposed to the activity of a trifluoromethyl analog. The notable advantages of …
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Group 10 Metal Catalytic Olefin Polymerization and Synthesis of Ethylene/Acrylate Block Copolymers
… developing group 10 metal catalysts for olefin polymerization and synthesis of ethylene/acrylates block copolymers. The distorted sandwich α-diimine Pd catalyst development exhibited high catalytic activity and living ethylene polymerization at low-pressure conditions. The resulted PEs are not …
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Novel Group 4 Metal Amido Complexes - syntheses, reactivity and olefin polymerization catalysis
… These complexes were found moderatly active for ethylene and styrene polymerization when activated with d-MAO giving syndiotactic polystyrene of high molecular weight and aluminum terminated polyethylene. The low activity of these complexes was attributed to the ligand transfer to aluminum during …
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N-Ligand Stabilized Lanthanide Complexes
… ligand these yttrium cations show very high ethylene polymerization activity at 80 °C in the presence of small amounts of aluminium alkyls. During these polymerizations a reversible polyethylene chain transfer between the organoyttrium cation and aluminium compounds was observed. The chain …
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Preparation, Characterization and Evaluation of Bimetallic Catalysts Prepared by Electroless Deposition Methods
… hydrogenation of acetylene in presence of excess ethylene to provide pure feed for ethylene polymerization process. </p> <p> The initial study on aqueous-phase catalytic glycerol oxidation reactions with molecular oxygen was described in chapter 5. The reactions were performed in both the absence …