Browsing by Subject "Sodium ions"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Synthesis of polybenzoxazine/clay nanocomposites by in situ thermal ring-opening polymerization using intercalated monomer
    (2011) Demir, K.D.; Tasdelen, M.A.; Uyar, T.; Kawaguchi, A.W.; Sudo, A.; Endo, T.; Yagci, Y.
    A new class of polybenzoxazine/montmorillonite (PBz/MMT) nanocomposites has been prepared by the in situ polymerization of the typical fluid benzoxazine monomer, 3-pentyl-5-ol-3,4-dihydro-1,3-benzoxazine, with intercalated benzoxazine MMT clay. A pyridine-substituted benzoxazine was first synthesized and quaternized by 11-bromo-1-undecanol and then used for ion exchange reaction with sodium ions in MMT to obtain intercalated benzoxazine clay. Finally, this organomodified clay was dispersed in the fluid benzoxazine monomers at different loading degrees to conduct the in situ thermal ring-opening polymerization. Polymerization through the interlayer galleries of the clay led to the PBz/MMT nanocomposite formation. The morphologies of the nanocomposites were investigated by both X-ray diffraction and transmission electron microscopic techniques, which suggested the partially exfoliated/intercalated structures in the PBz matrix. Results of thermogravimetric analysis confirmed that the thermal stability and char yield of PBz nanocomposites increased with the increase of clay content. © 2011 Wiley Periodicals, Inc.
  • Thumbnail Image
    ItemOpen Access
    Thinking outside the silicon box: molecular and logic as an additional layer of selectivity in singlet oxygen generation for photodynamic therapy
    (2009) Ozlem, S.; Akkaya, E. U.
    A simple derivative of a well-known dye bodipy appears to be a satisfactory sensitizer for singlet oxygen. Moreover, the rate of singlet oxygen generation can be modulated by two cancer-related cellular parameters, sodium ion concentration and acidity. Singlet oxygen generation rate is maximal when sodium ions and an organic acid were added. The operation of this molecular automaton follows AND logic, which introduces an additional layer of selectivity in the photodynamic action of the reagent. It should also be noted that in this system sensing, computing and actuating functions are realized within a single molecule. Copyright © 2008 American Chemical Society.