Download or read book Active Sites of Polymerization written by Gennady Zaikov and published by CRC Press. This book was released on 2005-03-28 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: The monograph is intended to systematize data on active sites and their kinetic and stereospecific heterogeneity (polysite phenomenon) in olefin and diene monomer ion, ion-coordination and complex radical polymerization processes. Questions of molecular-mass distribution of polymers obtained by ion and ion-coordination polymerization methods are discussed together with composition and stereo regularity distribution of olefin copolymers. Data on the influence of transition and non-transition metal origin and their ligand ambience, conditions of catalytic system preparation and polymerization are shown. Various assessment methods of polymerization active site distribution by kinetic activity and stereospecific action are considered. In particular, an assessment method for kinetic activity distribution at ion-coordination diene polymerization is described, mathematical simulation parameters for polymerization processes are shown, taking into account the polysite structure of catalytic systems. Of special attention are geometrical and electron structure of active sites in the ion-coordination polymerization by the quantum chemistry method, interrelation between reactivity of some types of active sites and stereospecificity of their action in diene polymerization. The importance of ratio between specific time elementary act duration at the diene injection, coordinated on an active site, and time of propagating macrochain end unit existence in the s-state at polydiene microstructure formation is indicated. Questions of the polysite mechanism occurrence in complex radical polymerization processes are discussed. A possibility for polymerization to proceed in both free-radical and complex related chain propagation sites is shown.
Download or read book Active Sites of Polymerization written by Gennady Zaikov and published by CRC Press. This book was released on 2005-03-28 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: The monograph is intended to systematize data on active sites and their kinetic and stereospecific heterogeneity (polysite phenomenon) in olefin and diene monomer ion, ion-coordination and complex radical polymerization processes. Questions of molecular-mass distribution of polymers obtained by ion and ion-coordination polymerization methods are di
Download or read book Stereoselective Polymerization with Single Site Catalysts written by Lisa S. Baugh and published by CRC Press. This book was released on 2007-11-29 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: New synthetic techniques allow chemists to modify polymer microstructures more precisely than ever, making it possible to design materials that meet increasingly demanding performance requirements. Written and edited by experts in the field, Stereoselective Polymerization with Single-Site Catalysts reviews how the relative stereochemistry of
Download or read book An Introduction to Polymer Chemistry written by D. Margerison and published by Elsevier. This book was released on 2013-10-22 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: An Introduction to Polymer Chemistry focuses on the fundamental chemistry of synthetic organic polymers of high molecular weight. This book explains the basic principles of polymer chemistry, from significant methods of molecular weight determination to the simpler mechanisms of polymerization. The osmotic, light scattering, and viscosity methods of molecular weight determination are fully discussed together with the kinetics of selected examples of condensation and free-radical addition polymerization. The main features of ionic polymerization are also elaborated. This text, however, does not cover the thermodynamics of polymer solutions or the methods of structure determination. This publication is a good reference to university and technical college students researching on polymer chemistry.
Download or read book Polymer Synthesis written by Paul Rempp and published by Wepf. This book was released on 1991 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organic and Physical Chemistry of Polymers written by Yves Gnanou and published by John Wiley & Sons. This book was released on 2008-03-03 with total page 629 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic and Physical Chemistry of Polymers provides a thorough introduction to the fundamentals of polymers, including their structure and synthesis as well as their chemical and physical properties. This accessible guide illuminates the increasingly important role of polymers in modern chemistry, beginning with the essentials, then covering thermodynamics, conformation, morphology, and measurements of molar masses; polymerization mechanisms, reaction of polymers, synthesis of block and graft polymers, and complex topologies; and the mechanical properties, rheology, polymer processing, and fabrication of fibers and films.
Download or read book Tailor Made Polymers written by John R. Severn and published by John Wiley & Sons. This book was released on 2008-06-25 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first comprehensive handbook on this exciting field provides readers with a clear understanding of the current state of the art, ingenious solutions and opportunities. Researchers from academia and industry present such emerging topics as multi-component systems and computational chemistry, as well as the latest developments in competing and complementary technologies. The result is a well-balanced and up-to-date overview.
Download or read book Mechanisms of Ionic Polymerization written by B.L. Erusalimskii and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last twenty years the literature on the processes of ionic polymerization has reached such a level that there is not a single question which is not covered by the information contained in the many monographs, reference books, and textbooks in this field. It is easy for the interested reader to find sources for in-depth study, for a superficial acquaintance with the fundamentals of the subject or with the general features of these processes. At the same time the field is being continually enriched by new facts which have not only broadened the data base but which influence existing concepts on the mechanisms of these reactions. Such influences often touch the very foundations of these concepts, i. e. , they go beyond simple descriptions of the structure of the pre-reaction states or earlier schemes. It is therefore appropriate to attempt a critical appraisal of the modern views on the mechanisms of formation of macro molecules in ionic systems which envisages, so far as is possible, the differentiating of fundamental and hypothetical conclusions or concepts. With this in mind we have preferred to address ourselves to the reader who is already quite well acquainted with the general litera ture. This has allowed us to dispense with detailed introductions to the questions discussed and to limit ourselves to brief comments on the fundamentals of the subject.
Download or read book Catalytic Polymerization of Olefins written by T. Keii and published by Elsevier. This book was released on 1986-04-01 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the proceedings of a symposium which was attended by researchers from all over the world who reported on and discussed recent advances in the field of catalytic polymerization of olefins. Over two decades have elapsed since the discovery of the Ziegler-Natta catalyst. Tremendous research effort has been aimed at improving this marvelous catalyst. In twenty-five years since the first publication, more than 15,000 papers and patents on the subject and on related subjects have appeared. This effort has yielded new generations of Ziegler-Natta catalysts with superior activity and stereospecificity. The complexities arising from the heterogeneity of the catalyst, however, have hindered understanding of the catalytic processes which take place on the catalyst surface. Nevertheless, many fundamental features of the catalyst system have now been clarified reasonably well. Recently a highly active homogeneous catalytic system has been developed, which is capable of catalyzing even isotactic polymerization of propene. There is no doubt that this finding will not only contribute to our understanding of the detailed mechanism of polymerization but also stimulate the development of various kinds of tailored polymers. Thus this subject will remain of paramount importance in the development of chemistry and polymer science for a long time to come.
Download or read book Coordination Polymerization written by Charles C. Price and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edwin J. Vandenberg, a long time researcher at the Research Center of Hercules Incorporated, was the 1981 winner of the American Chemical Society Award in Polymer Chemistry, sponsored by the Witco Chemical Corp. Following is the citation of the accomplishments which led to this award. "In recognition of his pioneering research that advanced polymer science and that led to the discovery and development of isotactic polypropylene, epichlorohydrin and propylene oxide elastomers, new polymerization catalysts, and the hydrogen method of controlling molecular weights of Ziegler polyolefins." It was my pleasure to arrange a symposium to celebrate this award at the Atlanta Meeting of the American Chemical Society on March 30, 1981. In considering the broad range of Vandenberg's contributions to polymer chemistry, it was decided to choose the subject of "Coordination Polymerization" for the symposium. This area is both one to which Vandenberg has made major contributions and one of great industrial and scientific interest. Since Vandenberg has been involved in coordination polymerization in both ring-opening and a-olefin type polymerizations, both were covered in the symposium, whose program follows. 1. "The Polymerization of 1,2-Epoxides Catalyzed by the Condensation Products of Metal-Containing Compounds with Alkylphosphates", T. Nakata, Research Laboratories, Osaka Soda Co., Ltd., 9 Otakasu-cho, Amagasaki City, Hyogo Pref. 660, Japan.
Download or read book Advances in Polyolefins written by R.B. Seymour and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 553 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stereoregular Polymers and Stereospecific Polymerizations written by Giulio Natta and published by Elsevier. This book was released on 2013-10-22 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stereoregular Polymers and Stereospecific Polymerizations: The Contributions of Guilio Natta and his School to Polymer Chemistry, Volume 1 covers the developments in understanding the reactions, nomenclature, and physico-chemical properties of polymers. This volume is composed of 82 chapters, and starts with surveys of the synthesis and crystal structure of polymers. Significant chapters are devoted to the characterization of crystalline polymers, with emphasis on the determination of their viscosity and molecular weight. Other chapters deal with stereospecific polymers of olefins, mechanism of stereospecific catalysis, reaction kinetics. This volume also considers the polymerization of synthetic elastomers and the copolymerization of olefins, as well as their reaction kinetics. The remaining chapters describe the X-ray characterization of isotactic polymers. This book is directed toward polymer chemists.
Download or read book Coordination polymerization written by James C.W. Chien and published by Elsevier. This book was released on 2012-12-02 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coordination Polymerization contains the proceedings of a symposium sponsored by the American Chemical Society and held at the University of California-Los Angeles on April 3, 1974. The papers explore developments in coordination polymerization and cover topics ranging from stereoselection and stereoelection in a-olefin polymerization to heterogeneous Ziegler-Natta polymerization; transition metal alkyl polymerization catalysts; chain transfer in Ziegler-type polymerization of ethylene; and stereospecific polymerization of diolefins by h3-allylic coordination complexes. This book is comprised of 13 chapters and begins with a discussion on Karl Ziegler's major contributions to the chemistry of free radicals, organo-alkali metal compounds, many-membered rings, and organotransition metallic compounds. The next two chapters focus on the origin of steric control in the polymerization of a-olefins, with emphasis on steroselection and stereoelection as well as the influence of the chirality of the transition metal on the stereoregularity of the resulting polymer. The problem of counting active sites is then addressed, and results obtained with various methods are compared. The mechanisms of initiation, propagation, termination, and transfers in polymerizations by (p-C5H5)2 TiCl2 catalysts are also considered, along with polymerizations by allyl, benzyl, trimethylsilmethyl, and other derivatives of Ti and Zr. The last three chapters examine the kinetics of Ziegler-Natta polymerization; the Langmuir adsorption mechanism; supported Ziegler-Natta catalysts; factors that affect the stereoregularity of polymerization of propylene by supported catalysts; and polymerizations of diolefins to equibinary polymers by h3-allylic coordination complexes. This monograph will be of interest to chemists as well as polymer scientists and engineers.
Download or read book Recent Advances in Mechanistic and Synthetic Aspects of Polymerization written by M. Fontanille and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to their specific properties, polymers with well-defined structures have been receiving increasing attention over the last several years. Owing to the wide variability of their properties, these specialty polymers have been used in various areas from biomedical engineering to electronics or energy applications. The synthesis of such polymers necessi tates the use of new methods of polymerization which derived from an insight into the mechanism of polymerization reactions. A NATO Advanced Research Workshop on "Frontiers in Polymerization Catalysis and Polymer Synthesis" was held in BANDOl (FRANCE) in February 1987. Its aim was to assess the new polymerization methods, as well as the latest advances in the mechanisms of conventional polymerization reactions together with their applications to the synthesis of new macromolecular structures. The financial support from the NATO Scientific Affairs Division which covered the "lecturers' accomodation and travel expenses as well as the organization charges of this event gave it international scope. Several industrial companies participate at the meeting and contributed to it success. The organizors who are also editors of these proceedings, want to express their thanks to both NATO Scientific Affairs Division and the companies present at the meeting.
Download or read book Catalytic Olefin Polymerization written by T. Keii and published by Elsevier. This book was released on 1990-09-12 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent development of a new generation of Ziegler-Natta Catalysts using either magnesium dichloride as carrier or methylaluminoxane as cocatalyst has markedly stimulated the research activity in the field of olefin polymerization. These discoveries have not only yielded economical processes for polyolefin production but also opened the way to a new generation of novel polymers. Moreover, the nature of active species is being clarified well by the effort to simplify catalyst systems. The present volume includes 38 papers from the 31 lectures and 18 posters presented at the symposium on `Recent Developments in Olefin Polymerization Catalysts', which covered the following topics: Overview of super-active homogeneous and heterogeneous catalysts, kinetic profile of olefin polymerization including copolymerization, characterization of catalysts and polymers, methods for the determination of active center concentration, role of Lewis bases on the catalysts isospecificity, polymerization mechanisms, and synthetic pathways for functionalized polyolefins. The contents are well balanced between fundamental research and application as well as between homogeneous and heterogeneous catalyst systems.
Download or read book Optically Active Polymers written by E. Sélégny and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first four volumes of the series on 'Charged and Reactive Polymers' have been devoted to polymers in solution (Voh. I and II) or in gel and membrane forms (Vols. III and IV). In correlation with charges, other physical or chemical properties of macro molecules have been considered. Understanding of charge and hydrophobic effects is equally important for synthetic and biopolymers or their systems. Optically Active Polymers are related to problems of the same class, since optical activity is an inherent property of both natural macromolecules as well as a great variety of polymers synthesized in the Jast twenty years. Optical activity is a physical spectral property of chiral matter caused by asymmetrical configurations, conformations and structures which have no plane and no center of symmetry and consequently have two mirror image enantiomeric forms of inverse optical rotation. The racemic mixture of chiral enantiomers is optically inactive. The most common form of optical activity was first measured at a constant wavelength by the angle of rotation of linearly polarized light. More recently the measurements have been extended to the entire range of visible and attainable ultraviolet regions where electronic transitions are observed, giving rise to the ORD technique (Optical Rotatory Dispersion). The Cotton effects appear in the region of optically active absorption bands; outside of these bands the plain curve spectrum is also dependent on all the electronic transitions of the chromophores.
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.
