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


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 


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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

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