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Ziegler-Natta Catalysis

1980
Publisher Summary This chapter discusses the scope of Ziegler catalysis; stereoselectivity, kinetics, and mechanism of Ziegler catalysis; homogeneous Ziegler–Natta catalysts; and side reactions in homogeneous catalysts. Ziegler catalysis involves rapid polymerization of ethylene and α-ole-fins with the aid of catalysts based on transition-element ...
Hansjörg Sinn, Walter Kaminsky
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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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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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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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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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Structure and Reactivity of Ziegler—Natta Catalyst Intermediates.

ChemInform, 2003
AbstractFor Abstract see ChemInform Abstract in Full Text.
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“Strong” and “weak” lattices in Ziegler‐Natta catalysts

Die Makromolekulare Chemie, Rapid Communications, 1987
Comparaison d'α-MgCl 2 , β-MgCl 2 , α-TiCl 3 et σ-TiCl 3 dans la polymerisation d ...
MARIGO, ANTONIO, A. Martorana, ZANNETTI, ROBERTO   +2 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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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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