Advertisement

The European Physical Journal E

, Volume 12, Supplement 1, pp 1–4 | Cite as

De-mixing dynamics of a binary liquid system in a controlled-pore glass

  • T. Hellweg
  • S. Schemmel
  • G. Rother
  • A. Brûlet
  • H. Eckerlebe
  • G.H. Findenegg
Article

Abstract.

The temperature-induced microphase separation of the binary liquid system iso-butyric acid+heavy water (iBA + D2O) in a mesoporous silica glass (CPG-10-75) of nominal pore width 7.5 nm was investigated by neutron spin-echo spectroscopy (NSE) and neutron small-angle scattering (SANS). Two mixtures of different composition were studied at different scattering angles at temperatures above and below the bulk phase transition temperature. The phase separation in the pore space is found to occur at a lower temperature than the bulk transition and extends over a significant temperature range. The effective diffusion coefficient derived from NSE at low scattering angles is found to decrease by one order of magnitude from 70 C to 20 C. This observation is attributed to the growing size of concentration fluctuations having a cut-off at ca. 8 nm, which corresponds to the mean pore size. The dynamics of the concentration fluctuations appears to be strongly influenced by the confinement in the pores, as it differs strongly from the bulk behaviour. These results are consistent with the preliminary results of the SANS study.

PACS codes.

64.60.Cn - Order-disorder transformations; statistical mechanics of model systems  61.12.Ex - Neutron scattering (including small-angle scattering 64.70.Ja - Liquid-liquid transitions 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1. L.D. Gelb, K.E. Gubbins, R. Radhakrishnan, M. Sliwinska-Bartkowiak, Rep. Prog. Phys. 62, 3573 (1999)CrossRefGoogle Scholar
  2. 2. A. Schreiber, H. Bock, M. Schoen, G.H. Findenegg, Molevular Phys. 100(53), 2997 (2002)Google Scholar
  3. 3. F. Porcheron, M. Schoen, Phys. Rev. E 66, 041205 (2002)CrossRefGoogle Scholar
  4. 4. P.G. de Gennes, J. Phys. Chem. 88, 6469 (1984)Google Scholar
  5. 5. M.Y. Lin, S.K. Sinha, J.M. Drake, X.-I. Wu, P. Thiyagarajan, H.B. Stanley, Phys. Rev. Lett. 72(14), 2207 (1994)CrossRefGoogle Scholar
  6. 6. S.B. Dierker, P. Wiltzius, Phys. Rev. Lett. 66, 1185 (1991)CrossRefGoogle Scholar
  7. 7. F. Formisano, J. Teixeira, Eur. Phys. J. E 1, 1 (2000)zbMATHGoogle Scholar
  8. 8. F. Formisano, J. Teixeira, J. Phys. Cond. Matt. 12, A351 (2000)Google Scholar
  9. 9. H.-H. Limbach, G. Buntkovsky, personel communication, slow relaxation is not accesible by NMRGoogle Scholar
  10. 10. Neutron Spin Echo, Vol. 124 of Lecture Notes in Physics, edited by F. Mezei (Springer Verlag, Berlin, 1980)Google Scholar
  11. 11. J.B. Hayter, in Scattering Techniques Applied To Supramolecular And Nonequilibrium Systems, edited by S.-H. Chen, B. Chu, R. Nossal (Plenum Press, New York, 1981), pp. 3–33Google Scholar
  12. 12. F. Mezei, C. Pappas, T. Gutberlet, Neutron Spin Echo Spectroscopy, Vol. 601 of Lecture Notes in Physics (Springer, Heidelberg, 2003)Google Scholar
  13. 13. P.G. de Gennes, Physica 25, 825 (1959)Google Scholar
  14. 14. A. Höhr, H.-B. Neumann, P.W. Schmidt, P. Pfeifer, D. Avnir, Phys. Rev. B 38, 1462 (1988)CrossRefGoogle Scholar
  15. 15. FLUKA, CPG, Tech. Rep., Fluka Chemie AGGoogle Scholar
  16. 16. P. Gansen, D. Wörmann, J. Phys. Chem. 88, 2655 (1984)Google Scholar
  17. 17. G. Rother, Adsorption und Phasentrennung binärer flüssiger Mischungen in Porensystemen, Ph.D. thesis, TU Berlin (2002)Google Scholar
  18. 18. H. Furukawa, Physica 123A, 497 (1984)CrossRefGoogle Scholar
  19. 19. P. Debye, H.R. Anderson Jr., H. Brumberger, J. Appl. Phys. 28, 679 (1957)Google Scholar
  20. 20. L. Auvray, P. Auroy, Scattering by Interfaces: Variations on Porod’s Law (Elsevier Science Publishers B.V., 1991), pp. 199–221Google Scholar
  21. 21. R. Papoular, La spectromètre par Echos de Spin de Neutron. Application à l’étude de la dynamique des polymers en solution, Ph.D. thesis, Université de Paris-Sud (1992)Google Scholar
  22. 22. S. Schemmel, G. Rother, T. Hellweg, H. Eckerlebe, G.H. Findenegg (2003), in preparationGoogle Scholar
  23. 23. B.J. Frisken, F. Ferri, D.S. Cannell, Phys. Rev. E 51, 5922 (1995)CrossRefGoogle Scholar

Copyright information

© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2003

Authors and Affiliations

  • T. Hellweg
    • 1
  • S. Schemmel
    • 1
  • G. Rother
    • 1
  • A. Brûlet
    • 2
  • H. Eckerlebe
    • 3
  • G.H. Findenegg
    • 1
  1. 1.Technische Universität Berlin, Stranski-Laboratorium, Strasse des 17.Juni 112, 10623 Berlin, Germany
  2. 2.Laboratoire Léon Brillouin, (CEA-CNRS) CEA-Saclay, 91191 Gif-sur-Yvette, France
  3. 3.GKSS Forschungszentrum GeNF, Max Planck Strasse, 21502 Geesthacht, Germany

Personalised recommendations