Rheologica Acta

, Volume 57, Issue 4, pp 339–347 | Cite as

Regularization methods for finding the relaxation time spectra of linear polydisperse polymer melts

Original Contribution


The calculation of discrete or continuous relaxation time spectra from rheometric measurables of polydisperse polymers is an ill-posed problem. In this paper, a curve fitting method for solving this problem is presented and compared to selected models from the literature. It is shown that the new method is capable of correctly predicting the molecular mass distributions of linear polydisperse polymer melts as well as their relaxation time spectra.


Polymer melts Relaxation time spectrum Polydisperse III-posed problems Regularization 



The author wishes to acknowledge I. Teasdale from the Institute of Polymer Chemistry at the Johannes Kepler University Linz, Austria for the help in conducting and evaluating HT-GPC measurements and M. Gall for the fruitful discussions. This research is funded by the European Union within the Horizon 2020 project under the DiStruc Marie Skłodowska Curie innovative training network; grant agreement no. 641839.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Forschungszentrum JülichICS 3JülichGermany
  2. 2.Laboratory for Soft Matter and BiophysicsKU LeuvenLeuvenBelgium

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