Results 171 to 180 of about 7,913 (200)

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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Morphology of Nascent Ziegler-Natta Polymers

Science, 1966
In the polymerization of α-olefins with heterogeneous Ziegler-Natta catalysts, the polymer is formed directly as long fibrillar units with folded chains. It is proposed that the fibrils are formed by the crystallization of polymer chains growing from the active sites on the catalyst surface, a process which is likened to root growth in whiskers.
P, Blais, R S, Manley
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Living Ziegler‐Natta Polymerizations: True or False?

Macromolecular Symposia, 2005
AbstractBased on the recent literature, the synthesis of novel polyolefin architectures via Ziegler‐Natta chemistry under living conditions appears to be a promising and fast‐growing area. In this paper, the appropriateness of the term “living” as applied to the said context is discussed in mechanistic terms, and the potential and the limitations of ...
BUSICO, VINCENZO, CIPULLO, ROBERTA, TALARICO, GIOVANNI   +2 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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ChemInform Abstract: Ziegler‐Natta Catalysis

ChemInform, 1997
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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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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Elementary steps in Ziegler‐Natta catalysis

Journal of Applied Polymer Science, 1976
AbstractThis paper is a short review of our recent advances in Ziegler‐Natta catalyst system of the type (C5H5)2TiRCl/AlEtn Clm. These are, for instance, the electronic changes after complex formation, the parallel reactions of the alkyl and chain transfer between both the Ti centers of two complexes and the Ti center and an Al center of two complexes;
Gerhard Fink, R. Rottler, D. Schnell, W. Zoller   +3 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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Ziegler-Natta catalysis I. Mechanism of polymerization of $alpha;-olefins with Ziegler-Natta catalysts*1

Journal of Catalysis, 1964
Abstract A mechanism for the polymerization of olefins is proposed. An essentially octahedrally coordinated ion of a transition element with empty or nearly empty t2g orbitals carrying in its coordination sphere one alkyl group and having one vacant octahedral position is supposed to be the active center.
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