A simple and effective scheme for data reduction of stress relaxation incorporating physical-aging effects: An analytical and numerical analysis

A simple methodology for obtaining viscoelastic parameters from the stress relaxation tests incorporating physical-aging effects is presented. The method assumes that the experimental data are in the linear viscoelastic domain. Three different mathematical representations of the viscoelastic stress relaxation modulus are analysed and used. Experimental data obtained from literature and simulated data with a random error are used to evaluate the proposed methodology. It is proved that it can capture very well the relaxation modulus of polymers irrespective of the mathematical representation used for the relaxation modulus. Moreover, the methodology proved to be reasonably insensitive to random noise. Extrapolation predictions were also evaluated for the proposed models with very good results.