Download or read book Novel N Ligand Stabilized Transition Metal Complexes of the Group IV Triad as Efficient Catalysts for Polymerization and Oligomerization written by Isabelle Haas and published by . This book was released on 2013 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis of Group IV Transition Metal Complexes and Their Applications as Catalysts for Ethylene Polymerization written by Khalil Ahmad and published by . This book was released on 2010 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Transition Metal Polymerization Catalysts written by Ray Hoff and published by John Wiley & Sons. This book was released on 2018-05-08 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Including recent advances and historically important catalysts, this book overviews methods for developing and applying polymerization catalysts – dealing with polymerization catalysts that afford commercially acceptable high yields of polymer with respect to catalyst mass or productivity. • Contains the valuable data needed to reproduce syntheses or use the catalyst for new applications • Offers a guide to the design and synthesis of catalysts, and their applications in synthesis of polymers • Includes the information essential for choosing the appropriate reactions to maximize yield of polymer synthesized • Presents new chapters on vanadium catalysts, Ziegler catalysts, laboratory homopolymerization, and copolymerization
Download or read book Polymer stabilized Transition Metal Nanocatalysts written by Olivier Jérémie Nguon and published by . This book was released on 2014 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: Novel polymeric architectures and analytical methods were designed for the synthesis, characterization, and applications of metallic nanocatalysts. Four main research areas were investigated, namely: i) palladium nanocatalysts, ii) metal content analysis by a novel microplasma-based technique, iii) polyion complex micelle-metal hybrid structures, and iv) nickel nanocatalysts. The solution and solid-state properties of dendrigraft (arborescent) polystyrene-graft-poly(2-vinylpyridine) copolymers were studied by dynamic light scattering (DLS) and atomic force microscopy (AFM). The unimolecular micelles exhibited good colloidal stability and narrow size distributions in organic solvents, and a fried egg morphology when deposited onto mica substrates. The preparation of stable colloidal Pd nanoparticles within the dendritic templates was reported for the first time. The diameter of the nanoparticles varied from 0.7 to 3.4 nm depending on the loading level, reduction time, and arborescent copolymer generation used. The catalytic activity of the colloidal Pd nanoparticles was evaluated in the Suzuki-Miyaura (SM) cross-coupling reaction under green conditions. Good catalytic activity and a positive dendritic effect were evidenced, although air-sensitivity and flocculation limited the activity and recyclability of the catalysts. To determine the concentration of Pd in the copolymers, a novel microplasma-based technique was applied in organic solvents for the first time. Metal quantification by microplasma-optical emission spectrometry revealed stoichiometric complexation of the Pd salt by the pyridine groups, and kinetic aggregation studies highlighted the benefits of the polymer for colloidal stability. To obtain Pd nanoparticles dispersible in high water content solutions, polyion complex micelles were synthesized from arborescent copolymers and double-hydrophilic block copolymers. The latter, viz. poly(acrylic acid)-block-poly(2-hydroxyethyl acrylate), were obtained by hydrolysis of poly(tert-butyl acrylate)-block-poly(2-trimethylsilyloxyethyl acrylate), synthesized by atom transfer radical polymerization. The self-assembled complexes formed supramolecular aggregates with hydrodynamic diameters of 132 to 354 nm and narrow size distributions. The assemblies exhibited thermo-responsive properties in ethanol, dissociating above ca. 35 °C and reforming upon cooling. The polyion complexes, with hydrodynamic diameters ranging from 110 to 306 nm, were stable in water and were used for the solubilization of Pd nanocatalysts for aqueous Suzuki-Miyaura reactions. Lastly, the properties of nickel nanoparticles prepared at Vale-Inco by a novel thermal decomposition method were investigated. The specific surface area of the bare nanopowders ranged from 6.4 to 97.2 m2g-1, and their catalytic activity in the hydrogenation of adiponitrile and mesityl oxide was higher than for commercial catalysts in some cases. Treatment of the nanoparticles with diethylenetriamine further improved their catalytic activity. Polymeric stabilizers were designed to maximize the dispersibility and catalytic activity of the nanopowders. The structures investigated included triblock copolymers of polystyrene with poly(ethylene oxide) or poly(2-vinylpyridine), and telechelic poly(ethylene glycol). Application of the polymer-stabilized nickel catalysts in hydrogenation yielded up to 15-fold increases in specific catalytic activity as compared to the bare particles. The polymer was also effective at preventing oxidation by air under storage.
Download or read book Alkene Polymerization Reactions with Transition Metal Catalysts written by Yury Kissin and published by Elsevier. This book was released on 2008-03-10 with total page 607 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past 30 years, the field of alkene polymerization over transition metal catalysts underwent several major changes:1. The list of commercial heterogeneous Ziegler-Natta catalysts for the synthesis of polyethylene and stereoregular polyolefins was completely renewed affording an unprecedented degree of control over the polymer structure.2. Research devoted to metallocene and other soluble transition-metal catalysis has vastly expanded and has shifted toward complexes of transition metals with multidentate ligands.3. Recent developments in gel permeation chromatography, temperature-rising fractionation, and crystallization fractionation provided the first reliable information about differences between various active centers in transition-metal catalysts.4. A rapid development of high-resolution 13C NMR spectroscopy resulted in greatly expanded understanding of the chemical and steric features of polyolefins and alkene copolymers. These developments require a new review of all aspects of alkene polymerization reactions with transition-metal catalysts. The first chapter in the book is an introductory text for researchers who are entering the field. It describes the basic principles of polymerization reactions with transition-metal catalysts, the types of catalysts, and commercially manufactured polyolefins. The next chapter addresses the principal issue of alkene polymerization catalysis: the existence of catalyst systems with single and multiple types of active centers. The subsequent chapters are devoted to chemistry and stereochemistry of elemental reaction steps, structures of catalyst precursors and reactions leading to the formation of active centers, kinetics of polymerization reactions, and their mechanisms. The book describes the latest commercial polymerization catalysts for the synthesis of polyethylenes and polypropylene The book provides a detailed description of the multi-center nature of commercial Ziegler-Natta catalysts. The book devotes specialized chapters to the most important aspects of transition metal polymerization catalysts: the reactions leading to the formation of active centers, the chemistry and stereochemistry of elemental polymerization steps, reaction kinetics, and the polymerization mechanism. The book contains an introductory chapter for researchers who are entering the field of polymerization catalysis. It describes the basic principles of polymerization reactions with transition-metal catalysts and the types of commercially manufactured polyolefins and copolymersThe book contains over 2000 references, the most recent up to end of 2006.
Download or read book Complexes of Group 4 Transition Metals with Novel ONSO and ONNO Type Ligands Coordination Chemistry and Catalytic Activity in Polymerization of Lactides written by Ayellet Maayani Stopper and published by . This book was released on 2014 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal Complex Catalysts Supercritical Fluid Polymerization Supramolecular Architecture written by and published by Springer. This book was released on 2013-10-03 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: recent resultsinadvancedorganometallicchemistry.Firstofall,somerecentexamples of the previous reviews concerning the Ziegler-Natta polymerization are cited [1—10]. Then, relevant new reports are surveyed in a systematic fashion.
Download or read book Transition Metals and Organometallics as Catalysts for Olefin Polymerization written by Walter Kaminsky and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: More than 30 years after the discovery of transition metals and organometal lics as catalysts for olefin polymerization these catalysts did not have lost their fascination. Since 1953 when Karl Ziegler has discovered the catalytic polymerization of ethylene leading to plastically formable polymers which are mechanically stable up to temperatures of about 100°C, synthetic polymers and rubbers have made their way right into private houses. This discovery has been a main impetus for the fast growing production of plastics. The stereoselective poly merization of propylene and other long-chain a-olefins first detected by Giulio Natta leads to an even broadened field of applications. Another enforcing factor were the developments of Standard Oil of Indiana and Phillipps Petroleum Company who engaged in the polymerization of a-olefins supported molybdenum, cobalt and later on chromium catalysts which clearly indicates the wide variety of suitable systems. This kind of research acknowledged merit when in 1963 the Nobel prize of chemistry was awarded to Ziegler and Natta. Although to a great extent there is a technical application for these catalysts, up to now the nature of the active centres and many reaction mechanisms are not completely known.
Download or read book N heterocyclic Carbene Group 4 Metal Complexes written by Charles Romain and published by . This book was released on 2011 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design of a novel NHC chelating ligand allowed the beneficial “association” of a soft NHC moiety with hard oxophilic group 4 metal which lead to the synthetize of a broad family of NHC group 4 metal complexes. Remarkably, the (OCO)MXX' group 4 chelates (X, X' = amido, alkoxide, chloride) were all found to be stable and robust entities with the NHC moiety truly and solely acting as an ancillary ligand under catalytic conditions. Attempts to access alkyl group 4 derivatives opened the way to an unprecedented NHC--involving alkyl/benzyl rearrangement reaction, there by constituting the first instance in which a NHC moiety coordinated to a high--oxidation--state and oxophilic transition metal NHC complex exhibited such a behavior. The prepared NHC group 4 metal alkoxide species were investigated in polymerization catalysis and found to be suitable initiators for the controlled and highly stereoselective ring--opening polymerization (ROP) of cyclic esters (lactide, a dimer of lactic acid) and cyclic carbonates (trimethylene carbonate), demonstrating the robustness of such species in catalytic conditions. These results constitute the first instance in which a NHC--based oxophilic metal catalyst is competitive and, to some extent, even performs better than current systems the area.
Download or read book Metal Catalysts in Olefin Polymerization written by Zhibin Guan and published by Springer Science & Business Media. This book was released on 2009-03-31 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polyolefin is a major industry that is important for our economy and impacts every aspect of our lives. The discovery of new transition metal-based catalysts is one of the driving forces for the further advancement of this field. Whereas the classical heterogeneous Ziegler-Natta catalysts and homogeneous early transition metal metallocene catalysts remain the workhorses of the polyolefin industry, in roughly the last decade, tremendous progress has been made in developing non-metallocene-based olefin polymerization catalysts. Particularly, the discovery of late transition metal-based olefin polymerization catalysts heralds a new era for this field. These late transition metal complexes not only exhibit high activities rivaling their early metal counterparts, but more importantly they offer unique properties for polymer architectural control and copolymerization with polar olefins. In this book, the most recent major breakthroughs in the development of new olefin polymerization catalysts, including early metal metallocene and non-metallocene complexes and late transition metal complexes, are discussed by leading experts. The authors highlight the most important discoveries in catalysts and their applications in designing new polyolefin-based functional materials.
Download or read book Transition Metal Reagents and Catalysts written by Jiro Tsuji and published by John Wiley & Sons. This book was released on 2002-08-16 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Im Laufe der vergangenen 35 Jahre wurden unzahlige Synthesewege entwickelt, bei denen Ubergangsmetallkomplexe entweder als Reagenzien oder als Katalysatoren fungieren. Dieses Buch bietet besonders denjenigen Synthesechemikern interessante und moderne Einblicke, die bisher noch nicht mit den vielfaltigen Moglichkeiten der Organometallchemie mit Ubergangsmetallen vertraut sind. Zu wichtigen ubergangsmetallkatalysierten Reaktionen werden Anwendungsbeispiele diskutiert. (01/00)
Download or read book Macromolecules Containing Metal and Metal Like Elements Volume 6 written by Alaa S. Abd-El-Aziz and published by John Wiley & Sons. This book was released on 2005-10-27 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: This series provides a useful, applications-oriented forum for the next generation of macromolecules and materials. The sixth volume in this series provides useful descriptions of the transition metals and their applications, edited by high-quality team of macromolecular experts from around the world.
Download or read book Reactivity and Catalytic Activity of Ligand stabilized Coordinatively Unsaturated Transition Metal Complexes written by Alan Charles Cooper and published by . This book was released on 1997 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Late Transition Metal Polymerization Catalysis written by Bernhard Rieger and published by Wiley-VCH Verlag GmbH. This book was released on 2003 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Even some fifty years after their discovery, transition metals have lost none of their fascination. The use of complex compounds in these elements has not only revolutionized synthesis in the laboratory, but has also led to them playing an important role in many industrial applications. Each year, millions of tons of plastics are produced around the world and, by varying the ligands in the catalytically active compounds, the properties of the resulting polymers can even be tailored for use. For this purpose, sandwich compounds from early transition metals have been common until now, but interest has focused increasingly on the late transition metals. In this book, the world's leading authors from research and industry discuss the latest developments in research into palladium, zinc, iron and nickel catalysis. In so doing, they systematically introduce readers to the basic principles and illustrate how these innovative catalysts can be effectively used for polymerizations. The result is an ideal reference work, invaluable for every organic chemist working in catalysis or polymer research.
Download or read book Main Group and Transition metal Complexes of a Novel Class of Amino alkoxide Ligands written by Christopher Michael Contos and published by . This book was released on 1999 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Novel Titanium IV Catalysts for Olefin Polymerization written by Saman Damavandi and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of olefin polymerization has been remarkably renewed with the use of metallocene and post metallocene catalyst. Novel transition-metal complexes were studied as catalysts in ethylene polymerization. The aim of this work is to investigate the feasibility of replacing the cyclopentadienyl ligands of metallocenes by bis(aminotropone) ligands as well as by new bis(imino)pyridinato ligands without losing the good properties of the metallocenes, such as high activity and formation of linear polymer. It was presumed that the polymerization mechanism and the active center in ethylene polymerization would be similar for iminopyridinato and metallocene catalysts. Titanium (IV) and nickel (II) catalysts based on bis(anilinotropone) ligands were prepared and their structures determined to clarify the relationship between structure of the catalyst precursor and polymerization results. In experimentation, the syntheses, structures and olefin polymerization behavior of Ti complexes containing a pair of chelating aminotropone [O-N] ligands are reported. DFT studies revealed that bis(aminotropone) Ti complexes, when activated, provide a metal alkyl in the cis position to a vacant coordina
Download or read book Synthesis of New Transition Metal Complexes and Applications for the Catalytic Ethylene Oligomerization and or Polymerization written by Suyun Jie and published by . This book was released on 2008 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polyolefins represent about half the market of the synthesized polymeric materials. The catalytic oligomerization of ethylene is currently the primary source of linear [alpha]-olefins which are extensively used for the preparation of synthetic lubricants, detergent intermediates, surfactants, plasticizers and as comonomers to synthesize linear low-density polyethylene (LLDPE). This work deals with the synthesis of 2-imino-1,10-phenanthroline and 2-imino-9-phenyl-1,10-phenanthroline tridentate ligand and of their iron, cobalt and nickel complexes of which some are very active in the catalytic ethylene oligomerization. Stereoelectronic parameters influencing the catalytic properties have been examined in detail. Furthermore, mono- and dinuclear cobalt complexes with phosphino- and phosphinito-oxazoline ligands have been prepared in the course of this thesis. They have shown moderate catalytic activity in the presence of MAO or AlEtCl2 as cocatalyst.
