Journal of Materials Science

, Volume 26, Issue 15, pp 4234–4240 | Cite as

Microstructure of a thermotropic random copolymer of hydroxybenzoic acid, isophthalic acid and hydroquinone (HBA-IA-HQ)

  • R. J. Spontak
  • A. H. Windle
  • W. A. MacDonald


Transmission electron microscopy has been used to study microstructural features in a thermotropic copolyester composed of 4-hydroxybenzoic acid, isophthalic acid and hydroquinone residues. Selected-area electron diffraction patterns indicate that thin sheared samples of the pure copolymer, and of an analogue containing glass filler, exhibit a dual molecular orientation in which the meridional maxima are closely periodic in scattering angle. Dark-field (DF) imaging in one set of the diffuse equatorial reflections reveals “bands” which have an average period of 200 nm. Annealing the material in the solid state at 250 °C leads eventually to a change in the structure in which the banded texture is replaced by regions of uniform orientation within which the molecules are aligned with the shear axis. Needle-like diffracting crystalline entities, measuring approximately 80 nm long, in the direction of the molecular chain axis, and 5–8 nm thick, have been imaged in DF using the first meridional reflection as the source of diffraction contrast.


Hydroquinone Electron Diffraction Pattern Molecular Orientation Random Copolymer Chain Axis 
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  1. 1.
    R. J. Spontak andA. H. Windle,J. Mater. Sci. 25 (1990) 2727.Google Scholar
  2. 2.
    Idem, Polymer 31 (1990) 1395.Google Scholar
  3. 3.
    G. R. Mitchell andA. H. Windle,Coll. Polym. Sci. 263 (1985) 230.Google Scholar
  4. 4.
    G. A. Gutierrez, R. A. Chivers, J. Blackwell, J. B. Stamatoff andH. Yoon,Polymer 25 (1984) 435.Google Scholar
  5. 5.
    R. A. Chivers, J. Blackwell andG. A. Gutierrez,ibid. 25 (1984) 435.Google Scholar
  6. 6.
    J. Blackwell, A. Biswas andR. C. Bonart,Macromolecules 18 (1985) 2126.Google Scholar
  7. 7.
    T. J. Lemmon, S. Hanna andA. H. Windle,Polym. Commun. 30 (1989) 2.Google Scholar
  8. 8.
    A. M. Donald andA. H. Windle,J. Mater. Sci. Lett. 4 (1985) 58.Google Scholar
  9. 9.
    A. H. Windle, C. Viney, R. Golombok, A. M. Donald andG. R. Mitchell,Faraday Disc. Chem. Soc. 79 (1985) 55.Google Scholar
  10. 10.
    R. Golombok, S. Hanna andA. H. Windle,Mol. Cryst. Liq. Cryst. 155 (1988) 281.Google Scholar
  11. 11.
    N. Carter, B. P. Griffin, W. A. MacDonald andT. G. Ryan, European Patent 275 163 (1988) (Imperial Chemical Industries plc).Google Scholar
  12. 12.
    W. J. Jackson andH. Kuhfuss,J. Polym. Sci. Poly. Chem. Ed. 14 (1976) 2043.Google Scholar
  13. 13.
    A. M. Donald andA. H. Windle, in “Recent Advances in Liquid Crystalline Polymers”, edited by L. Chapoy (Elsevier Applied Science, New York, 1987) Ch. 12.Google Scholar
  14. 14.
    A. B. Erdemir, D. J. Johnson andJ. G. Tomka,Polymer 27 (1986) 441.Google Scholar
  15. 15.
    A. B. Erdemir, D. J. Johnson, I. Karakan andJ. G. Tomka,ibid. 27 (1986) 441.Google Scholar
  16. 16.
    M. G. Dobb, D. J. Johnson andB. P. Saville,J. Polym. Sci., Polym. Symp. 58 (1977) 237.Google Scholar
  17. 17.
    J. R. Minter, K. Shimamura andE. L. Thomas,J. Mater. Sci. 16 (1981) 3303.Google Scholar
  18. 18.
    D. J. Johnson, I. Karacan andJ. G. Tomka,Polymer 31 (1990) 8.Google Scholar

Copyright information

© Chapman and Hall Ltd 1991

Authors and Affiliations

  • R. J. Spontak
    • 1
  • A. H. Windle
    • 1
  • W. A. MacDonald
    • 2
  1. 1.Department of Materials Science and MetallurgyUniversity of CambridgeCambridgeUK
  2. 2.ICI Advanced MaterialsWilton Materials Research CentreClevelandUK

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