Deprotonation of coordinated ethylene may start Phillips catalysis
نویسندگان
چکیده
منابع مشابه
Deprotonation of coordinated ethylene may start Phillips catalysis.
The metal-catalyzed polymerization of simple olefins, such as ethylene and propylene, has been one of the transformational discoveries in chemistry of the 20th century. It is difficult to imagine today’s civilization without ubiquitous plastics, such as polyethylene and related polymers. Although often attributed to Karl Ziegler and Giulio Natta, the winners of the 1963 Nobel Prize in Chemistry...
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The chromium/vanadium bimetallic Phillips catalysts developed by our research group have been proved to be a promising process to produce bimodal polyethylene using a single-reactor process. The vanadium loading of CrV-1/1, CrV-1/2, and CrV-1/3 has a significant effect on the polymerization activity, product molecular weight (MW), as well as th...
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Ethylene polymerization was carried out using Phillips chromium catalyst based on silica supports such as silica aerogel, SiO2 (Grace 643), and titanium modified SiO2 (G 643), and the results were compared with other catalysts based on SiO2 (Aldrich), SBA-15(Hex), SBA-15(Sp) and MCM-41. A combination of TGA, DSC, XRD, nitrogen adsorption, SEM, ICP, FTIR and other analyses were used to character...
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Legal analysis is a multistep process that performs the complex tasks of identifying real world activities through the lens of a predefined legal code and sets of laws. Based on a brief understanding of an issue a legal professional must make a recommendation on where to apply limited researching resources. We employ Naïve Bayes models in a parallel, nonmutually exclusive alignment towards the ...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2014
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.1411822111