Download or read book Copolymerization of Higher Olefins with Carbon Monoxide by Pd II Catalysts and Design of Nickel Palladium and Zirconium Complexes with Nitrogen based Ligands written by Mika Kettunen and published by . This book was released on 2004 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nickel Catalyzted Alternating Copolymerization of Carbon Monoxide and Ethylene written by Mengru Zhang and published by . This book was released on 2015 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Copolymerization of carbon monoxide and ethylene has been studied since 1940s, while the originally discovered catalyst was a nickel compound, cationic palladium (II) catalyst containing bidentate diphosphine and nitrogen ligands showed excellent activity at mild conditions. As a result, palladium catalysts became the mainstay of research in this area. In 1990s, Shell and BP started production of polyketone in full industrial using Pd-catalysts. The large scale production was then stopped at the beginning of this century for unannounced reasons, but the use of the expensive Pd as the catalyst is possibly a major problem for the commercial processes. Cationic nickel (II) complexes had much lower activity than the cationic Pd catalysts. The most efficient nickel (II) catalyst containing o-methoxyphenyl-modified P-P ligand showed moderate activity as 184 gPK/(gNi*h-1). In comparison, the commercial Pd catalysts have the activity of 6000 gPK/(gPd*h-1). Neutral nickel catalysts have been shown by other groups to have improved activities. In this work, we successfully designed and synthesized two zwitterionic nickel (II) catalysts. The highest activity can reach 8993 gPK/(gNi*h-1) and 15664 gPK/(gNi*h-1) respectively. Also, we isolated the real active intermediate, Ni-H, in the catalysis process.
Download or read book Mechanistic Studies of the Copolymerization of Olefins and Carbon Monoxide by Bidentate Phosphine Pd II Catalysts written by John S. Ledford and published by . This book was released on 1998 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanistic Investigations of the Nickel II and Palladium II Catalyzed Copolymerization of Carbon Monoxide and Olefins written by C. Scott Shultz and published by . This book was released on 2001 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Copolymerization and Co oligomerization of Cyclic Olefins and Carbon Monoxide with Palladium Catalysts written by Esther Mathilde Amevor-Stiefel and published by . This book was released on 1995 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Olefin Polymerization and Copolymerization Using Cationic Ni II and Pd II Catalysts written by Weijun Liu and published by . This book was released on 2004 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Emulsion Copolymerization of Alpha olefins with Carbon Monoxide Using Water soluble Palladium II Complexes written by Mahmoud Shaker Ahmed Sunjuk and published by . This book was released on 2003 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis of Polyketones from Zwitterionic Nickel Compound Catalyzed Copolymerization of Carbon Monoxide And Olefins written by Maohua Li and published by . This book was released on 2016 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition metal catalyzed alternating copolymerization of CO and olefins is an effective method for synthesis of aliphatic polyketons. Palladium and nickel catalysts are commonly employed to catalyze the polymerization with palladium catalysts being much more active and productive than nickel catalysts. Mechanistic studies of the nickel catalysts suggest that the resting states of cationic nickel catalysts likely involve intramolecular coordination of the ketone group of the propagating polyketone to nickel. To overcome this problem, our group recently developed a class of zwitterionic nickel catalysts, which have shown extremely high activity at the beginning of the polymerization but deactivate quickly. The overall productivity of our best zwitterionic catalyst is the highest among all nickel catalysts reported in the literature but still 2 orders of magnitudes lower than that of the palladium catalyst. In my thesis, I will show the low productivity leaves of nickel catalyst in the product. The residual nickel causes a decomposition process too close to the melting temperature of the polyketone. In order to improve the processability of the polyketone, I studied the terpolymerization of CO, ethylene, and 1-hexene and accidently discovered that catalyst productivity improves in the presence of 1-hexene.
Download or read book Comprehensive Coordination Chemistry II written by J. A. McCleverty and published by Newnes. This book was released on 2003-12-03 with total page 11845 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Coordination Chemistry II (CCC II) is the sequel to what has become a classic in the field, Comprehensive Coordination Chemistry, published in 1987. CCC II builds on the first and surveys new developments authoritatively in over 200 newly comissioned chapters, with an emphasis on current trends in biology, materials science and other areas of contemporary scientific interest.
Download or read book Polymer Molecular Weights written by Philip E. Slade and published by . This book was released on 1975 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alternating Copolymerisation of Carbon Monoxide with A olefins with a Homogeneous Pd Type Catalyst written by L. Barkhuysen and published by . This book was released on 1997 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Copolymerisation of Carbon Monoxide and Propene Catalysed by Diphosphine Palladium complexes written by Barbara Sesto and published by . This book was released on 2001 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Emulsion copolymerization of alpha olefins alpha olefins with carbon monoxide using water soluble Palladium II complexes written by Mahmoud Shaker Ahmed Sunjuk and published by . This book was released on 2002 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Emulsion Copolymerization of olefins alpha olefins with Carbon Monoxide Using Water Soluble Palladium II Complexes written by Mahmoud Shaker Ahmed Sunjuk and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Late Transition Metal Insertion Polymerization Catalysts written by Tobias Friedberger and published by . This book was released on 2015 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polyolefins are the number one commercially produced polymeric material by volume, and find ubiquitous uses as plastics, elastomers, and fibers. They are produced from gaseous olefins such as ethylene and propylene by the action of a transition metal catalyst. Despite tremendous academic and industrial efforts and successes in catalyst development over the past decades, the copolymerization of polar functionalized olefins with sufficiently high activities still remains a largely unsolved issue. Late transition metal catalysts were shown to be more suitable for this kind of polymerization reaction due to their generally lower oxophilic character. The main goal of this thesis was the development of novel late transition olefin polymerization catalysts based on ruthenium and palladium. Prior to this work, only few active olefin polymerization Ru-catalysts were reported. Several series of complexes based on ruthenium were synthesized, characterized and investigated for olefin polymerization. Ru(II)-complexes of the type RuCl2(N,N,N)L with facially coordinating nitrogen donor ligands (N,N,N = trispyridyl-, trispyrazoyl-, trisimidazoyl-methane derivatives) were found to be inactive towards ethylene polymerization. Employing bisanionic disulfonate phosphines as ligands gave Ru-complexes that produced linear, high-molecular weight polyethylene in the presence of an aluminum-alkyl based cocatalyst. Increasing the electrophilicity of the complex, by decreasing the donor strength of the ligand and using higher oxidation state Ru(IV)-complexes, the polymerization activity could be increased, and one of the highest activities for any Ru-based catalyst was observed. Polar additives such as acetone fully inhibited even the most electron-rich catalysts and copolymerization reactions yielded no polymer. In a different approach to solve the same problem, Pd-diimine complexes were modified with pendant olefin and boronate groups. Pd-diimine complexes can facilitate the copolymerization of ethylene with acrylates, and interactions of the pendant Lewis acid group with the functional, Lewis basic comonomer was anticipated to increase catalyst activity. However, no effect of a pendant pinacol boronate was observed on the incorporation ratio of methyl acrylate in room temperature copolymerizations. The ability of the pendant olefin to coordinate to cationic Pd-species resulted in hemilabile effects. Increased catalyst stability at the cost of decreased activities was found in comparison with unfunctionalized ligands.
Download or read book Pd II alpha diimine Catalysts for the Living and Block Copolymerization of Ethylene and alpha olefins written by Amy Collins Gottfried and published by . This book was released on 2002 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
