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Journal of Rheology / Volume 45 / Issue 1

J. Rheol. 45, 29 (2001); http://dx.doi.org/10.1122/1.1332387 (20 pages)

Rheology and nuclear magnetic resonance measurements under shear of sodium dodecyl sulfate/decanol/water nematics

Thomas Thiele and J.-F. Berret

Unité Mixte de Recherche CNRS/Université de Montpellier II n° 5581, Groupe de Dynamique des Phases Condensées, F-34095 Montpellier Cedex 05, France

Stefan Müller and Claudia Schmidt

Institut für Makromolekulare Chemie, Universität Freiburg, Stefan-Meier-Straße 31, D-79104 Freiburg, Germany

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We report on the rheology and deuteron nuclear magnetic resonance (NMR) measurements performed on the nematic lyotropic system sodium dodecyl sulfate, decanol, and water. For total surfactant and cosurfactant concentrations of about 30% by weight, we prepared nematic calamitic NC and nematic discotic ND solutions. We have studied the flow behavior of the NC and ND phases in terms of the transient shear stress using different rheological histories. In flow-reversal experiments, the transient response exhibits nonperiodic oscillations in the region of small deformations (γ = 20), which is followed by a long-lasting relaxation toward the stationary state. In the pseudo-Newtonian regime of the viscosity, we have found that the stress, when normalized to its long term value and plotted versus deformation, is shear-rate independent. 2H NMR measurements at rest and under shear were performed on nematic calamitic and discotic solutions prepared in D2O. At rest, the NMR spectra exhibit well-resolved doublet structures, which indicate an alignment of the director along the axis of the magnetic field. At shear rates large enough (math > 0.3 s−1), alignment is achieved with respect to the flow velocity. One finds alignment angles of 12 ° and 105 ° for the directors of the calamitic and discotic phase, respectively. Combining the results obtained by rheology and by NMR, we provide strong evidence that the NC and ND nematics of the sodium dodecyl sulfate / decanol system are textured nematics of the flow-aligning type. © 2001 Society of Rheology.

© 2001 Society of Rheology

KEYWORDS and PACS

Keywords

nuclear magnetic resonance, rheology, nematic liquid crystals, shear flow, Liquid crystals, NMR, Surfactants, Nematic

PACS

  • 83.80.Xz

    Liquid crystals: nematic, cholesteric, smectic, discotic, etc.

  • 83.85.Fg

    NMR/magnetic resonance imaging

PUBLICATION DATA

ISSN

0148-6055 (print)  

Publisher

Society of Rheology

RELATED DATABASES

Web of Science

View this record in Web of Science

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ARTICLE DATA

History
Received 11 Apr 00
Revised 17 Sep 00
Digital Object Identifier
http://dx.doi.org/10.1122/1.1332387

  1. Amaral, L. Q. and M. E. M. Helene, "Nematic domain in the sodium lauryl sulfate/water/decanol system," J. Phys. Chem. 92, 6094–6098 (1988). [ISI]
  2. Amaral, L. Q., M. E. M. Helene, D. R. Bittencourt, and R. Itri, "New nematic lyomesophase of sodium dodecyl sulfate," J. Phys. Chem. 91, 5949–5953 (1987). [Inspec] [ISI]
  3. Berghausen, J., J. Zipfel, P. Lindner, and W. Richtering, "Shear-induced orientations in a lyotropic defective lamellar phase," Europhys. Lett. 43, 683–689 (1998). [Inspec] [ISI]
  4. Berret, J.-F. and D. C. Roux, "Rheology of nematic wormlike micelles," J. Rheol. 39, 725–741 (1995)JORHD2000039000004000725000001. [ISI]
  5. Berret, J.-F., D. C. Roux, G. Porte, and P. Lindner, "Tumbling behavior of nematic wormlike micelles under shear flow," Europhys. Lett. 32, 137–142 (1995). [Inspec] [ISI]
  6. Burghardt, W. R., "Molecular orientation and rheology in sheared lyotropic liquid crystalline polymers," Macromol. Chem. Phys. 199, 471–488 (1998). [ISI]
  7. Caputo, F. E., W. R. Burghardt, and J. F. Berret, "Tumbling dynamics in a nematic surfactant solution in transient shear flow," J. Rheol. 43, 765–779 (1999)JORHD2000043000003000765000001. [ISI]
  8. Furo, I. and B. Halle, "Micelle size and orientational order across the nematic-isotropic transition: A field-dependent nuclear spin relaxation study," Phys. Rev. E 51, 466–477 (1995). [MEDLINE]
  9. Grabowski, D. A. and C. Schmidt, "Simultaneous measurements of shear viscosity and director orientation of a side-chain liquid crystalline polymer by rheo-NMR," Macromolecules 27, 2632–2640 (1994). [ISI]
  10. Hendrikx, Y. and J. Charvolin, "Structural relations between lyotropic phases in the vicinity of the nematic phases," J. Phys. (France) 42, 1427–1440 (1981). [Inspec] [ISI]
  11. Hendrikx, Y., J. Charvolin, M. Rawiso, L. Liébert, and M. C. Holmes, "Anisotropic aggregates of amphiphilic molecules in lyotropic nematic phases," J. Phys. Chem. 87, 3991–3999 (1983). [Inspec] [ISI]
  12. Itri, R. and L. Q. Amaral, "Micellar-shape anisometry near isotropic-liquid-crystal phase transition," Phys. Rev. E 47, 2551–2557 (1993). [MEDLINE]
  13. Itri, R. and L. Q. Amaral, "Study of the isotropic-hexagonal transition in the system SLS/H2O," J. Phys. Chem. 94, 2198–2202 (1990). [Inspec] [ISI]
  14. Larson, R. G., The Structure and Rheology of Complex fluids, (Oxford, University Press, New York, 1999).
  15. Larson, R. G. and M. Doi, "Mesoscopic domain theory for textured liquid crystalline polymers," J. Rheol. 35, 539–563 (1991)JORHD2000035000004000539000001.
  16. Larson, R. G. and D. W. Mead, "Development of orientation and texture during shearing of liquid-crystalline polymers," Liq. Cryst. 12, 751–768 (1992). [Inspec] [ISI]
  17. Lukaschek, M., S. Müller, A. Hasenhindl, D. A. Grabovski, and C. Schmidt, "Lamellar lyomesophases under shear as studied by deuterium nuclear magnetic resonance," Colloid Polym. Sci. 274, 1–7 (1996). [Inspec] [ISI]
  18. Marrucci, G., "Rheology of liquid crystalline polymers," Pure Appl. Chem. 57, 1545–1552 (1985). [ISI]
  19. Marrucci, G. and F. Greco, "Flow behavior of liquid crystalline polymers," Adv. Chem. Phys. 83, 331–404 (1993).
  20. Moldenaers, P. and J. Mewis, "Transient behavior of liquid crystalline solutions of poly-(benzyl glutamate)," J. Rheol. 30, 567–584 (1986)JORHD2000030000003000567000001.
  21. Moldenaers, P., H. Yanase, and J. Mewis, "Flow-induced anisotropy and its decay in polymeric liquid crystals," J. Rheol. 35, 1681–1699 (1991)JORHD2000035000008001681000001.
  22. Müller, S., C. Börschig, W. Gronski, C. Schmidt, and D. Roux, "Shear-induced states of orientation of the lamellar phase of C12E4/water," Langmuir 15, 7558–7564 (1999). [ISI]
  23. Müller, S., P. Fischer, and C. Schmidt, "Solid-like director reorientation in sheared hexagonal lyotropic liquid crystals as studied by nuclear magnetic resonance," J. Phys. II 7, 421–432 (1997). [Inspec] [ISI]
  24. Quist, P.-O., B. Halle, and I. Furo, "Micelle size and order in lyotropic nematic phases from nuclear spin relaxation," J. Chem. Phys. 96, 3875–3891 (1992)JCPSA6000096000005003875000001. [ISI]
  25. Roux, D. C., J.-F. Berret, G. Porte, E. Peuvrel-Disdier, and P. Lindner, "Shear induced orientations and textures of nematic wormlike micelles," Macromolecules 28, 1681–1687 (1995). [ISI]
  26. Siebert, H., D. A. Grabowski, and C. Schmidt, "Rheo-NMR study of non-flow-aligning side-chain liquid crystal polymer in nematic solution," Rheol. Acta 36, 618–627 (1997). [Inspec] [ISI]
  27. Vermant, J., M. Mortier, P. Moldenaers, and J. Mewis, "An evaluation of the Larson–Doi model for liquid crystalline pollymers using recoil," Rheol. Acta 38, 537–545 (1999). [Inspec] [ISI]
  28. Yu, L. J. and A. Saupe, "Observation of a biaxial nematic phase in potassium laurate-1-decanol mixtures," Phys. Rev. Lett. 45, 1000–1003 (1980).
  29. Zipfel, J., J. Berghausen, P. Lindner, and W. Richtering, "Influence of shear on lyotropic lamellar phases with different membranes defects," J. Phys. Chem. B 103, 2841–2849 (1999). [ISI]


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