Results 171 to 180 of about 4,997 (220)

Layer‐lattices in Ziegler–Natta catalysts

Journal of Polymer Science Part B: Polymer Physics, 1988
AbstractSome layered inorganic compounds of interest in old and new polymerization processes by Ziegler‐Natta stereospecific catalysis have been studied. The results are reported of an investigation concerning the crystallographic disorder phenomena in α‐TiCl3, VCl3, FeCl3, ball‐milled α‐MgCl2, β‐MgCl2, and in a new catalytic system produced according ...
ZANNETTI, ROBERTO, MAREGA, CARLA, MARIGO, ANTONIO, A. Martorana   +3 more
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Metallocene and Ziegler-Natta Catalysts

2021
Fifty years ago, Karl Ziegler and Natta won the Nobel Prize for their discovery of the catalytic polymerization of ethylene and propylene using titanium compounds with aluminum-alkyls as co-catalysts. Polyolefins are constantly growing and are now one of the most important highconsumption polymers. New metallocene/methylaluminoxane (MAO) catalysts have
Vinod Vishwakarma, Sandeep, Kulkarni, S.G.   +1 more
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Crystal Structures of Ziegler–Natta Catalyst Supports

Chemistry – A European Journal, 2011
AbstractThe crystal structures of three MgCl2⋅n EtOH complexes with n=1.5, 2.8, and 3.3 have been fully determined. Such complexes are the fundamental precursors for Ziegler–Natta polymerization catalysts used to produce polyolefins on a multimillion‐ton scale worldwide.
Malizia F., Fait A., CRUCIANI, Giuseppe
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Ziegler–Natta Catalysts: Regioselectivity and “Hydrogen Response”

ACS Catalysis, 2019
Advanced High Throughput Experimentation (HTE) methods were applied to quantify the regioselectivity and the so-called “hydrogen response” in propene polymerization of four Ziegler–Natta catalysts ...
Vittoria A., Meppelder A., Friederichs N., Busico V., Cipullo R.   +4 more
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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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