Download or read book Investigation of Nitroxide Mediated Thermal and Photochemical Reactions of Living Free Radical Polymerization written by William G. Skene and published by . This book was released on 2000 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Design Synthesis and Testing of N alkoxy Amine Initiators for Nitroxide mediated living Free Radical Polymerization written by Aaron Nilsen and published by . This book was released on 2005 with total page 1088 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitroxide Mediated Polymerization written by Didier Gigmes and published by Royal Society of Chemistry. This book was released on 2016 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first book dedicated to nitroxide-mediated polymerization and covers the history and development of NMP, as well as current techniques of academic and industrial interest.
Download or read book Nitroxide and Verdazyl Stable Free Radicals written by Julie L. Lukkarila and published by . This book was released on 2009 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the stable free radical polymerization (SFRP) process, stable free radicals (i.e. nitroxides) reversibly terminate polymer chain ends resulting in a significant decrease in termination reactions as compared to a conventional radical polymerization. Unimolecular initiators (unimers) have been used extensively in the SFRP process because they are extremely efficient initiating systems. More importantly, they are ideal model compounds for kinetic studies of the polymer-mediating agent bond. The major focus of this thesis is the preparation and kinetic studies of unique nitroxide and verdazyl containing unimers.The first part of this thesis describes the development of a distinctive procedure for the synthesis of a TEMPO containing acrylate unimer beginning with an oxymercuration reaction followed by reduction with sodium cyanoborohydride in the presence of TEMPO. This unimer provided the opportunity to study the reason for the difficulty of acrylate polymerizations using TEMPO as the nitroxide mediator.Next, the preparation of N-phenyl-9-triptycyl nitroxide, an ideal nitroxide to further study the effect of nitroxide hulk on the course of the SFRP process, is described. Unimers containing N-phenyl-9-triptycyl nitroxide were unstable and decomposed rapidly even at room temperature, constituting the first example of a unimer that is less stable than the corresponding nitroxide. A detailed description of the decomposition pathway is provided.Having demonstrated in our laboratory that verdazyl radicals can also mediate living-radical polymerizations of styrene and acrylates, we were interested in studying the kinetics of unimers prepared using these radicals. Unimer model compounds containing 6-oxoverdazyl radicals were prepared and kinetics studies were carried out using an 1H NMR technique recently developed in our laboratory.In the final section of this thesis a unique cycloaddition polymerization is examined. It has recently been reported that two 6-oxoverdazyl radicals react together to form an azomethine imine that undergoes a [3+2] 1,3-dipolar cycloaddition reaction with dipolarophiles like styrene and acrylates. To prepare macromolecules using this chemistry, 6-oxoverdazyl monomer units containing styrene and acrylate moieties were synthesized. Subsequent polymerization of these unique monomers gave the expected macrostructures along with a very interesting and novel [3.3]metacyclophane. The details of the polymerization, and NMR studies of the cyclophane, are provided.
Download or read book Radical Polymerization written by Irena O. Paulauskas and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the authors present topical research on new developments in radical polymerization. Topics discussed include interface radical reactions of functional polyperoxides for fabrication of three-dimensional polymeric structures; biomacromolecules in radical processes; nitroxide-mediated photo controlled/living radical polymerisation; alkaline anion-exchange membranes prepared by plasma polymerisation; advancements in controlled radical polymerisation for functional polymers; and thermal redox and photoinduced ring opening polymerisation reactions.
Download or read book Part I Exploratory Studies on the Generation and the Chemistry of 1 1 Difluoro 1 Phenylsulfanylmethyl Radical Part II New Initiators for Nitroxide mediated Living Free Radical Polymerization written by Thanchanok Thongpaisanwong and published by . This book was released on 2005 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biocidal Polymers written by Narendra Pal Singh Chauhan and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-10-21 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biocidal polymers are designed to inhibit or kill microorganisms such as bacteria, fungi and protozoans. This book summarizes recent findings in the synthesis, modification and characterization of various antimicrobial polymers ranging from plastics and elastomers to biomimetic and biodegradable polymers. Modifications with different antimicrobial agents as well as antimicrobial testing methods are described in a comprehensive manner.
Download or read book The Kinetics of Free Radical Polymerization written by Alastair M. North and published by Pergamon. This book was released on 1966 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Kinetics of Nitroxide Mediated Radical Polymerization of Styrene with a Unimolecular Initiator written by Mingxiao Zhou and published by . This book was released on 2009 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the results of a study on the kinetics of nitroxide-mediated radical polymerization of styrene with a unimolecular initiator. The primary objective was to obtain a more comprehensive understanding of how a unimolecular-initiating system controls the polymerization process and to clarify the effects of various reaction parameters. Previous work in this field has met with some difficulties in the initiator synthesis, such as low yield and inconsistency of molecular weight. These problems were overcome by adjusting reaction conditions and procedures. Better yields of initiator with consistent molecular weight were produced by the improved methods. Control of polymerization rate and polymer molecular weight in unimolecular nitroxide-mediated radical polymerization was studied by looking at the effects of the three main factors: initiator concentration, temperature, and the initiator molecular weight on polymerization rate, molecular weight and polydispersity. Results indicated that increasing the initiator concentration had no effect on polymerization rate at low conversion, but led to lower polymerization rate at high conversion; higher initiator concentration led to lower molecular weight of the resulting polymer. It was also found that temperature significantly increased the polymerization rate, yet had no effect on number-average molecular weight, Mn, at low conversion, while it caused a plateau at high conversion levels; there was no effect on weight-average molecular weight, Mw, through the whole conversion range. In addition, increasing initiator molecular weight was found to have no effect on either polymerization rate or molecular weight. The experimental molecular weights of the unimolecular system were compared to theoretical molecular weights based on ideal controlled radical polymerization (CRP). The results were found to be close to the theoretical values. This confirmed the advantages of the unimolecular system, namely, the degree of control over molecular weight was nearly ideal (for certain conditions); and molecular weights could thus be predicted by simply following general rules relating to CRP mechanisms.
Download or read book Exploiting Nitroxide mediated Controlled Radical Polymerization written by Maisha Kito Gray and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: By employing the appropriate choice and concentration of unimolecular initiator (A-T) or polystyrene (PS) macroinitiator, one allowing polymerization to proceed at moderate reaction temperatures (80--100°C), PS homopolymers with MWs in excess of 100,000 g/mol, possibly approaching 238,000 g/mol, have been made in a controlled manner (i.e., with polydispersity remaining below 1.5 and average chain length growing with increasing conversion).
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2004 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preparation of Poly ethylene Oxide block poly isoprene by Nitroxide Mediated Living Free Radical Polymerization written by Jakub Krzysztof Wegrzyn and published by . This book was released on 2003 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Living controlled Radical Polymerization in a Continuous Tubular Reactor written by Thomas Edward Enright and published by . This book was released on 2010 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant advances have been made in the understanding of living/controlled radical polymerization processes since their discovery in the early 1990's. These processes enable an unprecedented degree of control over polymer architecture that was previously not possible using conventional radical polymerization processes, and this has made possible the synthesis of many new and interesting materials. However, there has been only limited success in commercializing these new methods. Recently there has been increased focus on the development of more industrially viable processes. Dispersed aqueous phase reactions have received much attention because these water-based processes have several technical, economic, and environmental benefits over the more common solution and bulk reactions that were originally developed. Likewise, there has been some investigation of using continuous reactors that have potential technical and economic benefits over the more commonly employed batch reactors. This thesis presents an in-depth study that combines the three aforementioned technologies: living/controlled radical polymerization, dispersed phase aqueous reactions, and continuous reactors. Specifically, the system of interest is a nitroxide-mediated miniemulsion polymerization reaction in a continuous tubular reactor to produce polymer latex. Design of the continuous tubular reactor is discussed in some detail with a focus on specific technical challenges that were faced in building a functional apparatus for this system. Scoping experiments are described which identified a significant effect of temperature ramping rate that is critical to understand when moving to larger scale reactors for this system. The unexpected phenomenon of room temperature polymerization initiated by ascorbic acid is also described. There is demonstration for the first time that bulk and miniemulsion polymers can be produced in a tubular reactor under controlled nitroxide-mediated polymerization conditions, and copolymers can be produced. A detailed residence time distribution study for the tubular reactor is also shown, and several interesting phenomena are discussed that have implications on the practical operating conditions of the tubular reactor. This particular study makes it clear that one should experimentally verify the residence time distribution within a continuous system with the reactants of interest, and that model systems may not give an accurate picture of the real system.
Download or read book Computational Quantum Chemistry written by Masoud Soroush and published by Elsevier. This book was released on 2018-10-16 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Quantum Chemistry: Insights into Polymerization Reactions consolidates extensive research results, couples them with computational quantum chemistry (CQC) methods applicable to polymerization reactions, and presents those results systematically. CQC has advanced polymer reaction engineering considerably for the past two decades. The book puts these advances into perspective. It also allows you to access the most up-to-date research and CQC methods applicable to polymerization reactions in a single volume. The content is rigorous yet accessible to graduate students as well as researchers who need a reference of state-of-the-art CQC methods with polymerization applications. Consolidates more than 10 years of theoretical polymerization reaction research currently scattered across journal articles Accessibly presents CQC methods applicable to polymerization reactions Provides researchers with a one-stop source of the latest theoretical developments in polymer reaction engineering
Download or read book Accelerated Aging written by Robert L. Feller and published by Getty Publications. This book was released on 1995-03-02 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accelerated Aging: Photochemical and Thermal Aspects represents the culmination of more than 40 years of research by noted scientist Robert L. Feller. The book focuses on the long-term performance of materials such as wool, dyes, and organic compounds; their resistance to change when exposed to environmental factors such as oxygen, ozone, moisture, heat, and light; and their physical durability with handling and use over time. Processes of deterioration are discussed based on speeded-up laboratory studies designed to clarify the chemical reactions involved and their physical consequences.
Download or read book The Chemistry of Radical Polymerization written by Graeme Moad and published by Elsevier. This book was released on 2006 with total page 667 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book commences with a general introduction outlining the basic concepts of radical polymerization. This is followed by a chapter on radical reactions that is intended to lay the theoretical ground-work for the succeeding chapters on initiation, propagation and termination.
Download or read book Single Chain Polymer Nanoparticles written by José A. Pomposo and published by John Wiley & Sons. This book was released on 2017-08-18 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first book on this important and emerging topic presents an overview of the very latest results obtained in single-chain polymer nanoparticles obtained by folding synthetic single polymer chains, painting a complete picture from synthesis via characterization to everyday applications. The initial chapters describe the synthetics methods as well as the molecular simulation of these nanoparticles, while subsequent chapters discuss the analytical techniques that are applied to characterize them, including size and structural characterization as well as scattering techniques. The final chapters are then devoted to the practical applications in nanomedicine, sensing, catalysis and several other uses, concluding with a look at the future for such nanoparticles. Essential reading for polymer and materials scientists, materials engineers, biochemists as well as environmental chemists.
