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Raman and Fluorescence Studies of Thermotropic Liquid-Crystalline Oligomers with Different Type of Coils

  • Chae, Jong-Bok (Department of Chemistry, Kunsan National University) ;
  • Yu, Soo-Chang (Department of Chemistry, Kunsan National University) ;
  • Lee, Youn-Sik (Division of Environmental and Chemical Engineering, The Research Center of Industrial Technology)
  • Published : 2007.02.20

Abstract

Raman and fluorescence spectroscopies were employed to study the coil effects on the intermolecular structure of a rod-coil liquid crystalline (LC) oligomer, the esterification products of ethyl 4-[4'-oxy-4-biphenylcarbonyloxy]- 4'-biphenylcarboxylate with poly(propylene)oxides (PPO) (DP=12) and poly(ethylene oxide)s (PEO) (DP=12). Three different vibrational modes (carbonyl, aromatic C-H, and aromatic C=C) obtained from the Raman experiment at variable temperature indicate that PPO and PEO coils induce the hydrogen bonding in a different manner. Further information about the micro-environment around the mesogenic unit obtained by fluorescence excitation spectra of P12-4 (LC with PPO coil) and 12-4 (LC with PEO coil) suggests that the mesogenic unit of P12-4 is quite different from that of 12-4 in intermolecular structure. This study supports the results obtained only from Raman spectroscopy, providing more accurate information about the intermolecular structural changes of liquid crystalline polymers at a molecular level during the phase transitions.

Keywords

References

  1. Halperin, A. Macromolecules 1990, 23, 2724 https://doi.org/10.1021/ma00212a023
  2. Semenov, A. N. Mol. Cryst. Liq. Cryst. 1991, 209, 191 https://doi.org/10.1080/00268949108036194
  3. Williams, D. R. M.; Fedrikson, G. H. Macromolecules 1992, 25, 3561 https://doi.org/10.1021/ma00039a040
  4. Dias, F. B.; Voss, J. P.; Batty, S. V.; Wright, P. V.; Ungar, G. Makromol. Chem. Rapid Commun. 1994, 15, 961 https://doi.org/10.1002/marc.1994.030151209
  5. Lee, M.; Oh, N.-K. J. Mater. Chem. 1996, 6, 1079
  6. Lee, M.; Cho, B.-K.; Kim, H.; Yoon, J.-Y.; Zin, W.-C. J. Am. Chem. Soc. 1998, 120, 13258
  7. Bahadur, B. Liquid Crystals: Applications and Uses; World Scientific Publishing Co.: Singapore, 1990
  8. Huang, H. W.; Horie, K.; Tokita, M.; Watanabe, J. Macromol. Chem. Phys. 1998, 199, 1851 https://doi.org/10.1002/(SICI)1521-3935(19980901)199:9<1851::AID-MACP1851>3.3.CO;2-J
  9. Huang, H. W.; Horie, K.; Yamashita, T.; Machida, S.; Sone, M.; Tokita, M.; Watanabe, J. Macromolecules 1996, 29, 3485 https://doi.org/10.1021/ma9514030
  10. Takashi, H.; Horie, K.; Yamashita, T.; Machida, S.; Hannah, D. T. B.; Sherrington, D. C. Macromol Chem Phys. 1996, 197, 2703 https://doi.org/10.1002/macp.1996.021970909
  11. Horie, K.; Huang, H. W. Macromol Symp. 1997, 118, 229 https://doi.org/10.1002/masy.19971180132
  12. Huang, H. W.; Horie, K.; Tokita, M.; Watanabe, J. Polymer 1999, 40, 3013 https://doi.org/10.1016/S0032-3861(98)00548-5
  13. Kim, H. Bull. Korean Chem. Soc. 2006, 50, 429 https://doi.org/10.5012/jkcs.2006.50.6.429
  14. Kroschwitz, J. I. Polymers: Polymer Characterization and Analysis; John Wiley & Sons: New York, 1990
  15. June, J.; Choo, J.; Kim, D. J.; Lee, S. Bull. Korean Chem. Soc. 2006, 27, 277 https://doi.org/10.5012/bkcs.2006.27.2.277
  16. Yu, S.-C.; Choi, Y.; Yu, K. H.; Yu, J.; Choi, H.; Kim, D. H.; Lee, M. Macromolecules 2000, 33, 6527
  17. Wu, P. P.; Hsu, S. L.; Thomas, O.; Blumstein, A. J. Polym. Sci.: Part B, Polymer Physics 1986, 24, 827 https://doi.org/10.1002/polb.1986.090240409
  18. Ellis, G.; Lprente, J.; Marco, C.; Gomez, M. A.; Fatou, J. G.; Hendra, P. J. Spectrochim Acta 1991, 47A, 1353
  19. Yu, K. H.; Rhee, J. M.; Lee, Y.; Lee, K.; Yu, S.-C. Langmuir 2001, 17, 52
  20. Park, B. Y.; Jung, K. S.; Yu, S.-C.; Choi, H. S. J. Korean Chem. Soc. 2003, 47, 309 https://doi.org/10.5012/jkcs.2003.47.4.309
  21. Briscoe, B. J.; Stuart, B. H.; Thomas, P. S.; Williams, D. R. Spectrochim. Acta 1991, 47A, 1299
  22. Hirschberg, J. G.; Vereb, G.; Meyer, C. K.; Kirsch, A. K.; Kohen, E.; Jovin, T. M. Applied Optics 1998, 37, 1953 https://doi.org/10.1364/AO.37.001953

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