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Book Synthesis and Characterization of Modified Block Copolymers

Download or read book Synthesis and Characterization of Modified Block Copolymers written by Chi-Fung Chu and published by . This book was released on 1988 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Block Copolymers

Download or read book Block Copolymers written by Francisco Balta Calleja and published by CRC Press. This book was released on 2000-06-09 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: A summary of block copolymer chemical structures and synthesis. It discusses physical methods of characterization such as computer simulation, microhardness, dielectric spectroscopy, thermal mechanical relaxation, ultrasonic characterization, transmission electron microscopy, X-ray scattering, and NMR, among others. It also outlines rheological and processing parameters in the multiphase polymer systems with stable microstructures.

Book Synthesis and Characterization of Ionically Bonded Diblock Copolymers

Download or read book Synthesis and Characterization of Ionically Bonded Diblock Copolymers written by Lei Feng (Chemical engineer) and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Block copolymers consist of two or more incompatible polymer chains linked by covalent bonds. These block copolymer can separate into nanometer sized domains whose morphology depends upon the size of the block and interactions between them. The properties of block copolymers can be modified and potentially improved by introducing noncovalent interactions to replace covalent linkages between blocks to form supramolecular block copolymers. These kinds of materials combine the microphase separation inherent to block copolymers with the facile synthesis of supramolecular materials thereby affording new and unique materials. This dissertation focuses on synthesis and characterization of PS-b-PMA block copolymers with ion-pair junctions.Firstly, the chain-end sulfonated polystyrene ([omega]-sulfonated PS) was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization and postpolymerization modification. In the postpolymerization modification two methods were investigated: in the first one, the polymer was converted to a thiol-terminated polymer by aminolysis. Then a sulfonic acid end-group was produced then by oxidation of the thiol end-group with m-chloroperoxybenzoicacid (m-CPBA); in the second method, the RAFT-polymerized polymer was directly sulfonated by oxidation with m-CPBA. After purification by column chromatography, [omega]-sulfonated PS was obtained by both methods with greater than 95% end-group functionality as measured by titration. The sulfonic acid end-group could be neutralized with various ammonium or imidazolium counter ions through acid-base or ionic metathesis reactions. These polymers with ionic end-group can be used as model supramolecular building blocks.Secondly, ammonium end functionalized polymethylacrylate (PMA) was synthesized directly by RAFT polymerization using functional RAFT agent. Then chain-end sulfonated polystyrene and ammonium end functionalized polymethylacrylate (PMA) were used to synthesize A-B block copolymers by two different methods: the first method was by mixing two oppositely charged end group functionalized polymers; the second method was to ionically bond a RAFT agent to the chain end of an end sulfonated polymer to generate a supramolecular macro RAFT agent then an A-B block copolymer was prepared by RAFT polymerization using supramolecular macro-RAFT agent. The polymerization kinetics were investigated and the molecular weight and the chemical structure of the block copolymers were characterized by 1H-NMR and SEC. The results show that the ion-bonded supramolecular block copolymer, PS-PMA, have been successfully prepared with controlled molecular weight and narrow distribution.Thirdly, the morphology of the ion-bonded supramolecular PS-PMA diblock copolymers were investigated by small-angle X-ray scattering (SAXS) and rheological techniques. Several covalently bonded PS-PMA block copolymers were synthesized by RAFT polymerization and their micro domain structures and rheology behaviors were also investigated. The results showed that the electrostatic interactions between the end ion groups are able to overcome the thermodynamic repulsion of two blocks result in the formation of diblock copolymers with similar behaviors and morphology of traditional covalent bonded diblock copolymers and their micro domain structures remain to high temperatures.

Book Synthesis and Characterization of Poly 3 alkylthiophene containing Block Copolymers

Download or read book Synthesis and Characterization of Poly 3 alkylthiophene containing Block Copolymers written by Victor Ho and published by . This book was released on 2014 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conjugated polymers have been widely studied for their use in lightweight, flexible, and solution-processable electronic devices. However, the optimization of such polymer-based devices has been largely Edisonian in nature due to both a poor understanding of and an inability to control the complex hierarchical structure observed in semicrystalline polymers. In this thesis, we show that simple chemical modifications to commonly-studied conjugated polymers can have a large effect on the observed structure ranging from the unit cell to that on the order of device features. In particular, the self-assembly of block copolymers in which one of the components is optoelectronically-active is presented as a facile method to obtain nanostructured materials. For the work in this thesis, we will focus on poly(3-alkylthiophenes), a widely studied class of conjugated polymers due to their favorable optoelectronic properties, high solubility in organic solvents, and susceptibility to simple chemical modification. Although the synthesis of conjugated block copolymers has been presented in the past, complexities arising from crystallization of the conjugated moiety have dominated the observed solid state morphologies. Specifically, the crystallization of the semicrystalline block dictates the block copolymer microphase separation, a well-known phenomenon in the literature for non-conjugated semicrystalline block copolymers, which has resulted in solid state morphologies that do not differ significantly from that of the semiconducting homopolymer. To address this, we first show that the side chain chemistry controls the thermal transitions and optoelectronic properties in poly(3-alkylthiophenes). Such control over the crystallization kinetics provides an experimentally convenient approach to investigate the importance of the crystalline structure over a wide range of length scales on the optoelectronic properties. Furthermore, the ability to control the thermal transition temperatures can be used to directly manipulate, and thereby balance, the competition between the driving forces for crystallization and self-assembly. As evidence, the nanoscale structure is shown to be directly controlled via synthesis of block copolymers in which one block is the low melting temperature semiconducting polymer, poly(3-(2-ethylhexyl)thiophene). A wide range of morphologies with curved interfaces are observed which, in the past, have been precluded by the crystallization of poly(3-alkylthiophenes) with unbranched aliphatic side chains such as poly(3-hexylthiophene). Importantly, confinement of the conjugated polymer to nanoscale domains is not detrimental to the crystallinity or to charge transport over device-scale dimensions. Additionally, this approach is shown to be effective for a number of different chemistries providing a flexible methodology for obtaining periodic, semiconducting domains on the nanoscale. Together, these simple synthetic strategies can be used to tune the morphology of various length scales of thin film active layers and provide synthetic rules for design of novel semiconducting polymer systems.

Book Block Copolymers in Nanoscience

Download or read book Block Copolymers in Nanoscience written by Massimo Lazzari and published by Wiley-VCH. This book was released on 2007-06-27 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first book to take a detailed look at one of the key focal points where nanotechnology and polymers meet provides both an introductory view for beginners as well as in-depth knowledge for specialists in the various research areas involved. It investigates all types of application for block copolymers: as tools for fabricating other nanomaterials, as structural components in hybrid materials and nanocomposites, and as functional materials. The multidisciplinary approach covers all stages from chemical synthesis and characterization, presenting applications from physics and chemistry to biology and medicine, such as micro- and nanolithography, membranes, optical labeling, drug delivery, as well as sensory and analytical uses.

Book Block Copolymer Nanocomposites

Download or read book Block Copolymer Nanocomposites written by Galder Kortaberria and published by CRC Press. This book was released on 2016-10-14 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of the synthesis and characterization of nanocomposites based on block copolymers. Because of the self-assembly capability of block copolymers for the generation of nanostructures, besides their ability to nanostructure thermosetting matrices such as epoxy and polyester, binary or ternary nanocomposites can be prepared with different nanofillers such as nanoparticles and carbon nanotubes. The book starts with a review on nanocomposites based on block copolymers and nanoparticles synthesized with the use of surfactants, followed by a review on nanocomposites with metallic nanoparticles with polymer brushes and those with carbon nanotubes. A chapter is devoted to binary systems based on block copolymers and nanoparticles synthesized by sol-gel. A review on nanocomposites based on thermosetting matrices nanostructured with block copolymers (amphiphilic or chemically modified) is also presented for both epoxy and polyester resins. The work on ternary systems based on thermosetting matrices, block copolymers, and nanoparticles is presented next. The book concludes with a discussion on nanocomposites based on epoxy and block copolymers with azobenzene groups for optical purposes.

Book Synthesis and Characterization of Photocleavable Polymers and Block Copolymers

Download or read book Synthesis and Characterization of Photocleavable Polymers and Block Copolymers written by Hui Zhao and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Block Copolymers

Download or read book Block Copolymers written by Nikos Hadjichristidis and published by John Wiley & Sons. This book was released on 2003-04-28 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers may be classified as either homopolymers, consisting of one single repeating unit, or copolymers, consisting of two or more distinct repeating units. Block copolymers contain long contiguous blocks of two or more repeating units in the same polymer chain. Covering one of the hottest topics in polymer chemistry, Block Copolymers provides a coherent overview of the synthetic routes, physical properties, and applications of block copolymers. This pioneering text provides not only a guideline for developing synthetic strategies for creating block copolymers with defined characteristics, but also a key to the relationship between the physical properties of block copolymers and the structure and dynamics of materials. Covering features of the chemistry and physics of block copolymers that are not found in comparable texts, Block Copolymers illustrates the structure-activity relationship of block copolymers and offers suggestions for the design of specific applications. Divided into five sections-Block Copolymers includes chapters on: * Block Copolymers by Chemical Modification of Precursor Polymers * Nonlinear Block Copolymers * Adsorption of Block Copolymers at Solid-Liquid Interfaces * Theory of Block Copolymer Segregation * Phase Transformation Kinetics * Block Copolymer Morphology * Block Copolymer Dynamics Polymer chemists, physicists, chemical engineers, and materials scientists, as well as graduate students in polymer science, will find Block Copolymers to be an invaluable text.

Book Synthesis and Characterization of Ethylene propylene Block Copolymers

Download or read book Synthesis and Characterization of Ethylene propylene Block Copolymers written by Young Hwan Park and published by . This book was released on 1986 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Characterization of Some Novel Block Copolymers

Download or read book Synthesis and Characterization of Some Novel Block Copolymers written by Brian Carl Auman and published by . This book was released on 1987 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Modified Polymers Their Preparation and Properties

Download or read book Modified Polymers Their Preparation and Properties written by A. Romanov and published by Elsevier. This book was released on 2013-10-22 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modified Polymers, Their Preparation and Properties brings together the main lectures presented at the Fourth Bratislava Conference on Polymers held in Bratislava, Czechoslovakia, on July 1-4, 1975. Contributors explore the properties of modified polymers and their preparation, covering topics ranging from radiation crosslinking of polyvinyl chloride (PVC) with ethylene glycol dimethacrylate to chemical modification of polymers and the influence of chemical structure on the properties of polymers. This book is comprised of eight chapters and begins with a discussion on crosslinking of PVC in the presence of ethylene glycol dimethacrylate, studied by microcalorimetry, electron spin resonance, and structure investigation. The next chapter examines some characteristic features of chemical transformations of polymers on three examples: reactions of various organo-lithium bases onto the ester carbonyls of polymethylmethacrylate (PMMA); reaction of phenyl-lithium onto the carbonyl groups of PMMA; and chemical modification of polyvinylalcohol by metallation and subsequent reactions of alkylhalides or of propane sulfone. Subsequent chapters focus on how chemical structure affects polymer properties; alternating copolymer graft copolymers; acrylonitrile block and graft copolymers; and problems of polymer modification and the reactivity of functional groups of macromolecules. The final chapter is devoted to the separation and characterization of block and graft copolymers by thin-layer chromatography. This monograph will be a valuable source of information for chemists.

Book Synthesis and Characterization of Absorbable Block Copolymers for Vascular Applications

Download or read book Synthesis and Characterization of Absorbable Block Copolymers for Vascular Applications written by Kory Patrick Hamel and published by . This book was released on 1999 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: