Results 241 to 250 of about 13,429 (306)

Functionalized polymers from Ziegler-Natta catalysts

Journal of Molecular Catalysis A: Chemical, 1995
Abstract A new method for the preparation of functionalized polyolefins is presented. The method consists of two steps: (i) copolymerization of ethylene and/or an α-olefin with 1-iodo-3-butene (ii) elimination or substitution reaction of the iodine atom, by reaction with an organic salt of potassium, in the presence of a crown ether.
GALIMBERTI, MAURIZIO STEFANO, U. Giannini, E. Albizzati, S. Caldari, L. Abis   +4 more
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Electronic effects in homogeneous indenylzirconium Ziegler-Natta catalysts

Organometallics, 1990
A series of new bis(indenyl)zirconium(IV) complexes of the general formula ({eta}{sup 5}-4,7-X{sub 2}C{sub 9}H{sub 5}){sub 2}ZrCl{sub 2} and ({eta}{sup 5}-4,7-X{sub 2}C{sub 9}H{sub 5}){sub 2}Zr(CH{sub 2}H{sub 5}){sub 2} (where X = H, CH{sub 3}, OCH{sub 3}, and F) were synthesized in order to investigate the electronic effects of substitutents on the ...
PICCOLROVAZZI, N, PINO, P, CONSIGLIO, G, SIRONI, A, MORET, MASSIMO   +4 more
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Structure and Reactivity of Ziegler—Natta Catalyst Intermediates.

ChemInform, 2003
AbstractFor Abstract see ChemInform Abstract in Full Text.
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Rare-Earth Ziegler−Natta Catalysts:  Carboxylate−Alkyl Interchange

Organometallics, 2002
Alkylated rare-earth-metal centers are definitely formed in “Mischkatalysatoren”:  the homoleptic, tailor-made rare-earth carboxylate complexes {Ln(O2CC6H2iPr3-2,4,6)3}n (Ln = Y, La, Nd, Lu) react with trimethylaluminum to yield hexane-soluble monolanthanide complexes of the larger elements featuring a η2-coordinating tetraalkylaluminate ligand and a ...
Fischbach, Andreas, Perdih, Franc, Sirsch, Peter, Scherer, Wolfgang, Anwander, Reiner   +4 more
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Polyethylenimines: Multidentate Electron Donors for Ziegler–Natta Catalysts

The Journal of Physical Chemistry C, 2017
Polyethylenimines, polymers bearing amino functionalities, are studied for the first time as internal electron donors for Ziegler–Natta catalysts. An advantage of polyethylenimines (PEIs) compared to the conventional phthalate electron donors is their relative harmlessness. Interaction of PEI with MgCl2 support was studied using computational (DFT; M06-
Ville H. Nissinen, Mikko Linnolahti, Andrey S. Bazhenov, Tuula T. Pakkanen, Tapani A. Pakkanen, Peter Denifl, Timo Leinonen, Kumudini Jayaratne, Anneli Pakkanen   +8 more
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Accelerating the Research Approach to Ziegler–Natta Catalysts

Industrial & Engineering Chemistry Research, 2016
Despite 60 years of history and a stunning success, Ti-based Ziegler–Natta catalysts for the production of isotactic polypropylene remain black-box systems, and progress still relies on trial and error. This represents a limitation in a moment when the most widely used industrial systems, containing phthalates as selective modifiers, need to be ...
BUSICO, VINCENZO, CIPULLO, ROBERTA, Mingione, Alessio, Rongo, Luca   +3 more
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Synthesis and evaluation of a new three-metallic high-performance Ziegler–Natta catalyst for ethylene polymerization: experimental and computational studies

Polymer Bulletin, 2021
M. Abazari, R. Jamjah, Naeimeh Bahri‐Laleh, Ahad Hanifpour   +3 more
semanticscholar   +1 more source

Amalgamation of ziegler‐natta and metallocene catalysts

Macromolecular Symposia, 1997
AbstractThe MgCl2 supported half titanocenes and Ti(4, 4, 4‐trifluoro‐1‐phenyl‐1, 3‐butanedionato)2Cl2 catalysts were synthesized and applied to propene polymerization. Without supporting on MgCl2, those complexes displayed almost no activity even using methylaluminoxane (MAO) as cocatalyst.
K. Soga, J. Jin, E. Kaji, T. Uozumi, Y. Suzuki   +4 more
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Synthesis of highly improved Ziegler‐Natta catalyst

Journal of Applied Polymer Science, 2009
AbstractThe effects of media viscosity, mixing speed, and injection time on catalyst average particle size (APS), particle size distribution (PSD), and morphology in both conditions, with and without emulsifier, were investigated. Supports were prepared using a so‐called recrystallization method; then they were catalyzed under the same condition.
Majid Monji, Saeed Pourmahdian, Mohammad Vatankhah, Faramarz Afshar Taromi   +3 more
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Ziegler-Natta catalysts for olefin polymerizations

Progress in Polymer Science, 1997
Abstract This article reviews the recent developments of Ziegler-Natta and metallocene catalysts for olefin polymerizations. The roles of magnesium dichloride and electron donors on the activity and stereospecificity of Ziegler-Natta catalysts, as well as the roles of methylalumoxane and ligands on the activation and performance of metallocene ...
openaire   +1 more source