Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • Login
    View Item 
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Coil-to-Helix Transition of Poly(ethylene oxide) in Solution

    Thumbnail
    View/Open
    umi-umd-1722.pdf (2.952Mb)
    No. of downloads: 2478

    Date
    2004-07-30
    Author
    Alessi, Michael Louis
    Advisor
    Greer, Sandra C.
    Metadata
    Show full item record
    Abstract
    Poly(ethylene oxide) (PEO) is a simple polymer with repeating units [- C - C - O -] soluble in organic and aqueous solvents. The carbon atoms are hydrophobic; the oxygen atoms are hydrophilic and participate in hydrogen bonding. In all solvents in which PEO has previously been studied, PEO forms a coil in solution. Neutron scattering studies of PEO in isobutyric acid show that PEO undergoes a coil-to-rod transition in a solution of isobutyric acid (IBA). The stiffening is seen to progress smoothly with the addition of IBA, from a coil in D2O to a rod in pure deuterated-IBA. In addition to a solvent driven transition, a reversible rod-to-coil transition was seen to occur as a function of temperature, between 55 and 60 oC. Polarimetry experiments show that the rod formed by the PEO in solution is actually a helix, the conformation that PEO has in the solid state. It is also shown that, through the use of chiral impurities and temperature, the direction of the helix can be affected, allowing polymer folding to be influenced on a molecular level.
    URI
    http://hdl.handle.net/1903/1747
    Collections
    • Chemical and Biomolecular Engineering Theses and Dissertations
    • UMD Theses and Dissertations

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    Browse

    All of DRUMCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility