The sedimentation velocity of a gelled polymer

  • W. Borchard
  • H. M. Hinsken
Gels, Emulsions, And Dispersions
Part of the Progress in Colloid & Polymer Science book series (PROGCOLLOID, volume 107)


In a centrifugal field a gel is a continuous system with a radial concentration gradient due to the volume force of the field and diffusion. In contrary to the known definition of the sedimentation coefficient of a gel where the movement of the gel meniscus is related to the driving force, the velocity of the center of mass of the polymer with respect to its acceleration has been introduced using irreversible thermodynamics. It is shown that there will be no induction period of this velocity although the meniscus does not move. From extrapolation to times where the selected rotor speed had just been reached, the sedimentation coefficient of the polymer of a κ-carrageenan/water gel could be determined. In addition to the sedimentation coefficient, the phenomenological and the diffusion coefficients were also calculated from the data. Differences between the sedimentation of a sol and a gel are pointed out and discussed.

Key words

Centrifugal field gel sedimentation diffusion κ-carrageenan/water 


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  1. 1.
    Svedberg T, Pedersen KO (1940) In: Ostwald W (ed) Die Ultrazentrifuge, Handbuch der Kolloidwissenschaft, Vol. VII. Steinkopff-Verlag, Dresden and Leipzig, pp 26–29Google Scholar
  2. 2.
    Borchard W (1991) Progr Colloid Polym Sci 86:84CrossRefGoogle Scholar
  3. 3.
    Cölfen H, Borchard W (1991) Progr Colloid Polym Sci 86:102Google Scholar
  4. 4.
    Hinsken HM, Borchard W (1995) Colloid Polym Sci 273:913CrossRefGoogle Scholar
  5. 5.
    Johnson P (1971) J Photographic Sci 19:49Google Scholar
  6. 6.
    Bohonek J, Spühler A, Ribeaud M, Tomka 1 (1976) In: Cox J (ed) Academic Press, London, p 37Google Scholar
  7. 7.
    Johnson P, Matcalfe JC (1967) Eur Polym J 3:423CrossRefGoogle Scholar
  8. 8.
    Haase R (1963) Thermodynamik der irreversiblen Prozesse. D. Steinkopff, Darmstadt, p. 239 ff.Google Scholar
  9. 9.
    Fujita H (1962) Mathematical Theory of Sedimentation Analysis. Academic Press, New York, p 9 onwardsGoogle Scholar
  10. 10.
    Hinsken HM Thesis in preparationGoogle Scholar
  11. 11.
    Snoeren THM (1976) In: Veeman H, Zonen BV (eds) Kappa-Carrageenan, A study on its Physico-chemical Properties, Sol-gel Transition and Interaction with Milk Proteins.Google Scholar
  12. 12.
    Rehage G (1959) Sympos über Makromoleküle, Wiesbaden, II A 15Google Scholar

Copyright information

© Dr. Dietrich Steinkopff Verlag GmbH & Co. KG 1997

Authors and Affiliations

  • W. Borchard
    • 1
  • H. M. Hinsken
    • 1
  1. 1.Angewandte Physikalische Chemie der Gerhard-Mercator-Universität Gesamthochschule DuisburgDuisburgGermany

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