Journal of Polymer Research

, Volume 13, Issue 1, pp 79–84

Miscibility and Luminescence Properties of MEH-PPV/DPO-PPV Polyblends

Article

Abstract

Poly(2-methoxy-5-(2′-ethyl-hexyloxy)-p-phenylenevinylene) (MEH-PPV) and poly(2,3-diphenyl-5-octyl-p-phenylenevinylene) (DPO-PPV) are basically immiscible as verified by fluorescence spectroscopy and differential scanning calorimetry. This immiscibility results in insufficient energy transfer from DPO-PPV to MEH-PPV in photoluminescence. A vertically segregated structure with DPO-PPV green domains dispersing on the MEH-PPV-rich matrix was observed in a spin-cast film by two-photon excitation microscopy. The turn-on voltages for electroluminescence (EL) of polyblends were lower than those of their individual pristine polymers, while their EL quantum efficiencies were higher. Because both the highest occupied molecular orbital and the lowest unoccupied molecular orbital levels of MEH-PPV are higher than those of the DPO-PPV, the energy gap of the vertical heterojunction (1.98 eV) in polyblends is lower than that of the pristine MEH-PPV (2.14 eV), which is believed to result in the improved EL properties.

Key words

conjugated polymers luminescence polymer light-emitting diode poly(2-methoxy-5-(2′-ethyl-hexyloxy)-p-phenylenevinylene) polyblends 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    D. Braun and A. Heeger, J. Appl. Phys. Lett., 58, 1982 (1991).CrossRefGoogle Scholar
  2. 2.
    I. D. Parker, J. Appl. Phys., 75, 1656 (1994).CrossRefGoogle Scholar
  3. 3.
    G. Padmanaban and S. Ramakrishnan, J. Am. Chem. Soc., 122, 2244 (2000).CrossRefGoogle Scholar
  4. 4.
    Y.-L. Fan and K.-F. Lin, J. Polym. Sci. Part A: Polym. Chem., 43, 2520 (2005).CrossRefGoogle Scholar
  5. 5.
    T. W. Lee and O. O. Park, Adv. Mater., 12, 801 (2000).CrossRefGoogle Scholar
  6. 6.
    T. W. Lee, O. O. Park, L. M. Do and T. Zyung, Synth. Met., 117, 249 (2001).CrossRefGoogle Scholar
  7. 7.
    H.-L. Chou, K.-F. Lin, Y.-L. Fan and D.-C. Wang, J. Polym. Sci. Part B: Polym. Phys., 43, 1705 (2005).CrossRefGoogle Scholar
  8. 8.
    B.-H. Sohn, K. Kim, D. S. Doi, Y. K. Kim, S. C. Jeoung and J.-L. Jin, Macromolecules, 35, 2876 (2002).CrossRefGoogle Scholar
  9. 9.
    L. S. Park, Y. S. Han, S. D. Kim and D. U. Kim, Synth. Met., 117, 237 (2001).CrossRefGoogle Scholar
  10. 10.
    Y. Xiao, W.-L. Yu, Z. Chen, W. Huang and A. J. Heeger, Synth. Met., 106 165 (1999).CrossRefGoogle Scholar
  11. 11.
    S. M. Chang, P. K. Su, G. J. Lin and T. J. Wang, Synth. Met., 137, 1025 (2003).CrossRefGoogle Scholar
  12. 12.
    C.-C. Chiu, K.-F. Lin and H.-L. Chou, J. Polym. Sci. Part A: Polym. Chem., 41, 2180 (2003).CrossRefGoogle Scholar
  13. 13.
    H. G. Gilch and W. L. Wheelwright, J. Polym. Sci. Part A: Polym. Chem., 4, 1337 (1966).CrossRefGoogle Scholar
  14. 14.
    H.-L. Chow, K.-F. Lin, Y.-K. Han and D.-C. Wang, Bull. Coll. Eng. NTU, 89, 111 (2003).Google Scholar
  15. 15.
    Y. Li, Y. Cao, J. Gao, D. Wang, G. Yu and A. J. Heeger, Synth. Met. 99, 243 (1999).CrossRefGoogle Scholar
  16. 16.
    K. M. Gaab, and C. J. Bardeen, J. Phys. Chem. B, 108, 4619 (2004).CrossRefGoogle Scholar
  17. 17.
    T. Q. Nguyen, R. Y. Yee and B. J. Schwartz, J. Photochem. Photobiol. A, 144, 21 (2001).CrossRefGoogle Scholar
  18. 18.
    T. Huser and M. Yan, Synth. Met., 116, 333 (2001).CrossRefGoogle Scholar
  19. 19.
    T. Q. Nguyen, B. J. Schwartz, R. D. Schaller, J. C. Johnson, L. F. Lee, L. H. Haber and R. J. Saykally, J. Phys. Chem. B, 105, 5153 (2001).CrossRefGoogle Scholar
  20. 20.
    H.-L. Cheng and K.-F. Lin, Synth. Met., 122, 387 (2001).CrossRefGoogle Scholar
  21. 21.
    H.-L. Cheng and K.-F. Lin, J. Mater. Chem., 12, 2270 (2002).CrossRefGoogle Scholar
  22. 22.
    J. R. Lakowicz, Principles of Fluorescence Spectroscopy. Plenum, New York, 1983, Chap. 3.Google Scholar
  23. 23.
    Y. Liu, M. S. Liu, X. C. Li and A. K. Y. Jen, Chem. Mater., 10, 3301 (1998).CrossRefGoogle Scholar
  24. 24.
    T. W. Lee and O. O. Park, Adv. Mater., 12, 801 (2000).CrossRefGoogle Scholar
  25. 25.
    S.-H. Chen, A.-C. Su, Y.-F. Huang, C.-H. Su, G.-Y. Peng and S.-A. Chen, Macromolecules, 35, 4229 (2002).CrossRefGoogle Scholar
  26. 26.
    D. W. Van Krevelen, Properties of Polymers: Their Correlation with Chemical Structure: Their Numerical Estimation and Prediction from Additive Group Contributions. Elsevier, Amsterdam, 1990.Google Scholar
  27. 27.
    J.-S. Kim, P. K. H. Ho, C. E. Murphy and R. H. Friend, Macromolecules, 37, 2861 (2004).CrossRefGoogle Scholar
  28. 28.
    A. C. Morteani, A. S. Dhoot, J.-S. Kim, C. Silva, N. C. Greenham, C. Murphy, E. Moons, S. Cina, J. H. Burroughes and R. H. Friend, Adv. Mater., 15, 1708 (2003).CrossRefGoogle Scholar
  29. 29.
    R. Jakubiak, C. J. Collison, W. C. Wan, L. J. Rothberg and B. R. Hsieh, J. Phys. Chem. A 103, 2394 (1999).CrossRefGoogle Scholar
  30. 30.
    M. Lor, J. Thielemans, L. Viaene, M. Cotlet, J. Hofkens, T, Weil, C. Hampel, K. Müllen, J. W. Verhoeven, M. Van der Auweraer and F. C. De Schryver, J. Am. Chem. Soc., 124, 9918 (2002).CrossRefGoogle Scholar
  31. 31.
    I. D. Parker, J. Appl. Phys., 75, 1656 (1994).CrossRefGoogle Scholar
  32. 32.
    A. C. Morteani, R. H. Fiend and C. Silva, Chem. Phys. Lett., 391, 81 (2004).CrossRefGoogle Scholar

Copyright information

© Springer 2005

Authors and Affiliations

  • Hsuan-Liang Chou
    • 1
  • King-Fu Lin
    • 1
  • Ding-Chang Wang
    • 2
  1. 1.Department of Material Science and EngineeringNational Taiwan UniversityTaipeiTaiwan, Republic of China
  2. 2.Ritekdisplay CorporationTaiwanRepublic of China

Personalised recommendations