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Dynamics in concentrated polymer solutions studied using dynamic light scattering

  • W. Brown
Chapter
Part of the Progress in Colloid & Polymer Science book series (PROGCOLLOID, volume 91)

Abstract

Concentrated solutions (volume fraction 0.1–0.9) of polystyrene (PS) in toluene and of polybutylacrylate (PBA) in dioxane have been examined using dynamic light scattering (DLS) as a function of angle and temperature. With PS there is a pronounced maximum in the cooperative diffusion coefficient (D c) at about Φ=0.5 as the glassy state is approached. By contrast, with PBA, which has a very low T g, there is a crossover to a stronger concentration dependence for D c, which is attributed to an increase in solvent mobility. In the PS/toulene system at Φ=0.78 a transition is noted between the diffusion mode and the main relaxational mode. At 17°C q-independence is observed and at 50 °C q 2-dependence. At Φ=0.89, both relaxations are observed simultaneously in the DLS time window, the slower process being a structural relaxation.

Key words

Photon correlation polystyrene concentrated solutions relaxation times 

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References

  1. 1.
    Brown W, Štěpánek P (1991) Macromolecules 24:5848Google Scholar
  2. 2.
    Brown W, Schillén K, Johnsen R.M, Koňák C, Dvoranek L (1992) Macromolecules 25:802CrossRefGoogle Scholar
  3. 3.
    Brown W, Johnsen RM, Koňák C, Dvoranek L (1991) J Chem Phys 95:8568CrossRefGoogle Scholar
  4. 4.
    Brown W, Johnsen RM, Koňák C, Dvoranek L (1992) J Chem PHys 96:6274CrossRefGoogle Scholar
  5. 5.
    Nicolai T, Brown W, Johnsen RM, Štěpánek P (1990) Macromolecules 23:1165CrossRefGoogle Scholar
  6. 6.
    Nicolai T, Brown W, Hvidt S, Heller K (1990) Macromolecules 23:5088CrossRefGoogle Scholar
  7. 7.
    Brown W, Nicolai T (1990) Colloid Polym Sci 268:977CrossRefGoogle Scholar
  8. 8.
    de Gennes P-G (1979) Scaling Concepts in Polymer Physics. Cornell University Press, LondonGoogle Scholar
  9. 9a.
    Wang CH (1991) J Chem Phys 95:3788CrossRefGoogle Scholar
  10. 9b.
    Wang CH (1992) Macromolecules 25:1524CrossRefGoogle Scholar
  11. 10.
    Fytas G (1989) Macromolecules 22:211CrossRefGoogle Scholar
  12. 11.
    Wang CH, Fischer EW (1985) J Chem Phys 82:632, 4332CrossRefGoogle Scholar
  13. 12.
    Fytas G, Floudas G, Ngai KL (1990) Macromolecules 23:1104CrossRefGoogle Scholar
  14. 13.
    Rehage G, Fuhrmann J (1970) Discuss Faraday Soc 49:208CrossRefGoogle Scholar
  15. 14.
    Patterson (1981) 27th Int Symp Macromol II:709Google Scholar
  16. 15.
    Ngai KL, Wang CH, Fytas G, Plazek DL, Plazek DJ (1987) J Chem Phys 86:4768CrossRefGoogle Scholar
  17. 16.
    Lempert W, Wang CH (1981) Polym Prepr (Am Chem Soc Div Polym Chem) 22:80Google Scholar
  18. 17.
    Morris RL, Amelar S, Lodge TP (1988) J Chem Phys 89:6523CrossRefGoogle Scholar
  19. 18.
    von Meerwall ED, Amelar S, Smeltzly MA, Lodge TP (1989) Macromolecules 22:295CrossRefGoogle Scholar
  20. 19.
    Fytas G, personal communicationGoogle Scholar

Copyright information

© Dr. Dietrich Steinkopff Verlag GmbH & Co. KG 1993

Authors and Affiliations

  • W. Brown
    • 1
  1. 1.Inst. of Physical ChemistryUniv. of UppsalaUppsalaSweden

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