Results 131 to 140 of about 700 (179)

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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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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Polymerization of phenylacetylene on Ziegler-Natta catalysts

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1968
1. 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, M. I. Cherkashin, A. A. Berlin   +2 more
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An Electrochemical Study of the Ziegler - Natta Catalyst

Analytical Letters, 1982
Abstract 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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Prepolymerization of ethylene with a Ziegler–Natta catalyst

Journal of Applied Polymer Science, 2007
AbstractThe 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, Mohammad Vakili, Neda Tafi   +2 more
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Stereochemical Control in Ziegler-Natta Catalysts

1987
The 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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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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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 ...
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Ziegler-Natta catalysts for olefin polymerization

2021
SUMERIN VICTOR, KIPIANI GEORGY
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