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Metallocene and Ziegler-Natta Catalysts
2021Fifty 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 +1 more
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Accelerating the Research Approach to Ziegler–Natta Catalysts
Industrial & Engineering Chemistry Research, 2016Despite 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 +3 more
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Ziegler–Natta Catalysts: Regioselectivity and “Hydrogen Response”
ACS Catalysis, 2019Advanced 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. +4 more
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Structure and Reactivity of Ziegler—Natta Catalyst Intermediates.
ChemInform, 2003AbstractFor Abstract see ChemInform Abstract in Full Text.
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An Electrochemical Study of the Ziegler - Natta Catalyst
Analytical Letters, 1982Abstract An anodic voltanmetric study was made of the Ziegler-Natta catalyst in tetrahydrofuran using a rotating platinum electrode. It was shown that these measurements could be used as an indication of the activity of the catalyst. It was also observed that the catalyst and the cocatalyst (diethyl aluminum chloride) formed an electrochemically ...
Thomas C. Franklin, Masahiro Ohta
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Polymerization of phenylacetylene on Ziegler-Natta catalysts
Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 19681. The kinetics of the polymerization of phenylacetylene on catalysts (α, δ-TiCl3)-(C3H5)3Al in heptane and benzene medium was studied by a dilatometric method. 2. The influence of the concentration of the components of the catalytic system on the rate of polymerization of phenylacetylene was investigated, and the observed constants ...
G. I. Bantsyrev +2 more
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Prepolymerization of ethylene with a Ziegler–Natta catalyst
Journal of Applied Polymer Science, 2007AbstractThe slurry prepolymerization of ethylene using TiCl4/MgCl2 as a catalyst was investigated. A 23‐factorial experimental design method was employed to study the effects of the temperature, hydrogen, and active cocatalyst‐to‐catalyst molar ratio (Al/Ti) on the catalyst activity, prepolymer melt flow index, and powder bulk density.
Ahmad Mirzaei +2 more
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Amalgamation of ziegler‐natta and metallocene catalysts
Macromolecular Symposia, 1997AbstractThe 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 +4 more
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Advances in Ziegler-Natta catalysts for polypropylene
Kinetics and Catalysis, 2006The most advanced catalysts, based on MgCl2-supported TiCl4 and electron donors, are able to provide polypropylenes with an isotacticity higher than 99%. This, together with the continuous progress made in understanding and exploiting the role of electron donors in controlling polymer MW and MWD, has led to polypropylene products having an ...
A. Ferraro +4 more
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Stereochemical Control in Ziegler-Natta Catalysts
1987The remarkably high level of stereoselectivity associated with magnesium chloride-based catalysts is realized only in the presence of a selectivity control agent (SCA), frequently an aromatic ester.1 The usual effect of the SCA is to reduce activity while significantly enhancing stereoselectivity.2 Fortunately, the reduction in productivity (65%) is ...
S. E. Wilson, W. L. Callender, R. C. Job
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