Rheology pp 377-383 | Cite as

Dynamic of Flexible and Large Macromolecules in Elongational Flow Using Flow Refringence

  • Robert Cressely
  • Roger Hocquart


Several studies of the effect of a transverse shear stress on a macromolecular solution have been made by flow birefringence (F. B.) (e. g. (1)). For consequence of the unceasing rotation motion of the particles in this type of flow, the deformations of the flexible macromolecules remain generally small. But, in elongational flow and in the particular case where there is no rotational part, we can expect, in certain restrictive conditions, very strong molecular deformation such as the transition of the macromolecule from the coiled state to a streched form. Theoritical studies of this transition have been carried out (2–4), but there are only a few experiments comparable with proposed theories. The F.B. is a technique which lends itself perfectly to these studies. Localized flow birefringence (L.F.B.), appearing in experiments as thin luminous lines and showing the extention of the macromolecule in specific parts of the solution have first been observed with a system of opposed jets (5). But, in order to perform quantitative optical measurements, exploitable without ambiguity, we are limited to the use of two dimensional elongational flow. Such flows have already been realized in a system of two (6–9), four (10–11) or six rolls (12) and in the wake of an adequate obstacle in a uniform flow.


Transverse Shear Stress Elongational Flow Coiled State Luminous Line Large Macromolecule 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. (1).
    V.N. Tsvetkov, “Never Methods of Polymer Caracterisation”, Bacond Ke, Ed, New York Interscience (1964)Google Scholar
  2. (2).
    A. Peterlin, Pure Appl. Chem. 12, 563 (1966)CrossRefGoogle Scholar
  3. (3).
    P.G. De Gennes, J. Chem. Phys. 60, 5030 (1974)ADSCrossRefGoogle Scholar
  4. (4).
    E.J. Hinch, Phys. of Fluids, 20, 10, 523 (1977)CrossRefGoogle Scholar
  5. (5).
    M.R. Mackley, A. Keller, Phil.Trans.Roy.Soc.Lond. 278, 29 (1975)ADSCrossRefGoogle Scholar
  6. (6).
    F.C. Franck, M.R. Mackley, J. Polym.Sci. 14, 1121 (1976)Google Scholar
  7. (7).
    R. Cressely, R. Hocquart, O. Scrivener, Optica Acta, 25, 559 (1978)ADSCrossRefGoogle Scholar
  8. (8).
    C.J. Farrel, A. Keller, J. Colloid Polym. Sci., 256, 966 (1978)CrossRefGoogle Scholar
  9. (9).
    R. Cressely, R. Hocquart, O. Scrivener, Optica Acta, 26, 1173 (1976)ADSCrossRefGoogle Scholar
  10. (10).
    D.G. Crowley, F.C. Frank, M.R. Mackley, R.G. Stephenson J. Polym. Sci. 14, 1111 (1976)Google Scholar
  11. (11).
    D.P. Pope, A. Keller, J. Colloid Polym, Sci. 255, 633 (1977)CrossRefGoogle Scholar
  12. (12).
    M.U. Berry, M.R. Mackley, Trans. Roy. Soc. Lond. 287, 1, (1977)ADSCrossRefGoogle Scholar
  13. (13).
    R. Cressely, R. Hocquart, Optica Acta, to be publishedGoogle Scholar
  14. (14).
    O. Scrivener, C. Berner, R. Cressely, R. Hocquart, R. Sellin, N.S. Vlachos, J. Non Newt. Fluid. Mech., 5, 475 (1979)CrossRefGoogle Scholar
  15. (15).
    R. Cressely, R. Hocquart, A. Lyazid, O. Scrivener, I.U.P.A.C. Makro — Mainz, II, 999 (1979)Google Scholar
  16. (16).
    A. Lyazid, O. Scrivener, Teitgen, VIII Int. Congress of Rheologie, NAPLES (1980)Google Scholar

Copyright information

© Springer Science+Business Media New York 1980

Authors and Affiliations

  • Robert Cressely
    • 1
  • Roger Hocquart
    • 1
  1. 1.Faculté des SciencesLaboratoire d’Optique MoléculaireMetzFrance

Personalised recommendations