Advertisement

Rheologica Acta

, Volume 33, Issue 6, pp 530–541 | Cite as

Calculation of discrete retardation spectra from creep data — II. Analysis of measured creep curves

  • J. Kaschta
  • F. R. Schwarzl
Article

Abstract

An algorithm for the calculation of discrete, logarithmic equidistant retardation spectra from creep or recovery is applied to experimental data in different regions of consistency. Spectra in the glass-rubber transition region are given for technical poly(styrene), poly(methylmethacrylate), and poly(carbonate) as well as the course of all characteristic compliance type functions. The spectrum in the terminal region of a poly(styrene) of narrow molecular weight distribution is calculated both from creep and recovery data. The course of the dynamic moduli calculated from the spectra and by direct conversion is found in excellent agreement to measurements by means of a dynamic viscometer.

Key words

Glass transition discrete retardation spectrum terminal transition entanglement transition recovery 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Baumgärtel M, Winter HH (1992) Interrelation between continuous and discrete relaxation time spectra. J NonNewt Fluid Mech 44:15 – 36Google Scholar
  2. Graessley WW (1974) The entanglement concept in polymer rheology, chap 5. Adv Polym Sci 16, Springer BerlinGoogle Scholar
  3. Kaschta J, Schwarzl FR (1994) Calculation of discrete retardation spectra from creep data — I. Method, Rheol Acta (this volume)Google Scholar
  4. Kaschta J (1991) Zum Nachgiebigkeitsverhalten amorpher Polymere im Glas-Kautschuktibergang. Thesis, ErlangenGoogle Scholar
  5. Link G, Schwarzl FR (1985) A measuring device for the precise evaluation of creep and recovery data. Rheol Acta 24:211–219Google Scholar
  6. Montfort JP, Marin G, Monge P (1984) Effects of constraint release on the dynamics of entangled linear polymer melts. Macromolecules 17:1551–1560Google Scholar
  7. Nederveen CJ, van der Wal CW (1968) A torsional pendulum for the determination of shear modulus and damping around 1 Hz. Rheol Acta 6:316–323Google Scholar
  8. Orbon SJ, Plazek DJ (1979) Recoverable compliance of a series of bimodal molecular weight blends of polystyrene. J Polym Sci Phys Ed 17:1871–1890Google Scholar
  9. Plazek DJ, O'Rouke VM (1971) Viscoelastic behaviour of low molecular weight polystyrene. J Polym Sci A-2 8:209 – 243Google Scholar
  10. Schwarzl FR, Staverman AJ (1952) Higher approximations of relaxation spectra. Physica 18:791–799Google Scholar
  11. Schwarzl FR (1969) The numerical calculation of storage and loss compliance from creep data for linear viscoelastic materials. Rheol Acta 8:6–17Google Scholar
  12. Schwarzl FR (1970) On the interconversion of linear viscoelastic material functions. Pure and Appl Chem 23:219 – 234Google Scholar
  13. van der Wal CW, Drent RHJWA (1969) A torsional creep apparatus. Rheol Acta 7:265–271Google Scholar
  14. Wolf M (1992) Zur Molekulargewichtsabhängigkeit des rheologischen Verhaltens von PS und PMMA unterschiedlicher Molekularmassenverteilung. Thesis ErlangenGoogle Scholar

Copyright information

© Steinkopff-Verlag 1994

Authors and Affiliations

  • J. Kaschta
    • 1
  • F. R. Schwarzl
    • 1
  1. 1.Institute for Materials Science University of Erlangen-NürnbergErlangenGermany

Personalised recommendations