Advertisement

Conformational Characterization of the Single Crystal Surface

  • Y. A. Chang
  • A. Hiltner
Part of the Polymer Science and Technology book series

Abstract

The surfaces of polyethylene single crystals have been selectively brominated, and the conformational sensitivity of the C-Br infrared stretching modes has been utilized to characterize the fold structure. From the analysis of low molecular weight compounds, band assignments have been made for each of the six possible conformations of the two C-C bonds adjacent to the C-Br bond. The gauche conformations predominate in the spectra of single crystals. The calculated conformational populations were observed to change with temperature particularly in the region of the dynamic mechanical a relaxation. As a result of similarities observed in the infrared spectra of brominated crystals and one of the model compounds, bromocyclooctane, models for the chain fold have been proposed. These consist of nine carbon atoms arranged in the crown or twisted-crown structures. Both models conform well to the lattice constraints of the {110} fold.

Keywords

Single Crystal Surface Trans Conformation Gauche Conformation Meso Form Chain Fold 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    A. Keller, Philos. Mag., 2, 1171 (1957).ADSCrossRefGoogle Scholar
  2. 2.
    E.W. Fischer, Z. Naturforsch. Tel A, 12, 753 (1957).ADSGoogle Scholar
  3. 3.
    P.H. Geil, J. Polym. Sci., 17, 447 (1957).Google Scholar
  4. 4.
    I.R. Harrison and E. Baer, J. Polym. Sci., A-2, 9, 1305 (1971).CrossRefGoogle Scholar
  5. 5.
    M. Eguiluz, H. Ishida and A. Hiltner, J. Polym. Sci. Polym. Phys. Ed., 17, 893 (1979).ADSCrossRefGoogle Scholar
  6. 6.
    M. Eguiluz, H. Ishida and A. Hiltner, J. Polym. Sci. Polym. Phys. Ed., 18, 2295 (1980).ADSCrossRefGoogle Scholar
  7. 7.
    H.C. Brown and K. Murray, J. Am. Chem. Soc, 81, 4108 (1959).CrossRefGoogle Scholar
  8. 8.
    D.J. Blundell and A. Keller, J. Macromol. Sci. Phys., B2, 337 (1968).Google Scholar
  9. 9.
    Y.A. Chang, Ph.D. Thesis, Case Western Reserve University, January, 1982.Google Scholar
  10. 10.
    P. Klaeboe, J.J. Kothe and K. Lunde, Acta Chem. Scan., 10, 1465 (1956).CrossRefGoogle Scholar
  11. 11.
    E.L. Eliel, Conformational Analysis, John Wiley, N.Y., 1965.Google Scholar
  12. 12.
    R.G. Snyder, J. Mol. Spectrochim., 28, 273 (1968).ADSCrossRefGoogle Scholar
  13. 13.
    B. Wunderlich, Macromolecular Physics, Vol. I, p. 96, Academic Press, N.Y., 1973.Google Scholar
  14. 14.
    P. Corradini, V. Petraconne and G. Allegra, J. Macromol. Sci. Phys., B4, 770 (1971).ADSGoogle Scholar
  15. 15.
    J.D. Hoffman, C. Williams and E. Passaglia, J. Polym. Sci., C14, 173 (1966).Google Scholar

Copyright information

© Plenum Press, New York 1983

Authors and Affiliations

  • Y. A. Chang
    • 1
  • A. Hiltner
    • 1
  1. 1.Department of Macromolecular Science, Case Institute of TechnologyCase Western Reserve UniversityClevelandUSA

Personalised recommendations