Thermodynamics Research Center / ThermoML | Thermochimica Acta

ABSTRACT

We have measured adiabatic calorimetry as well as dielectric relaxation spectroscopy in the linear and non-linear response regime of viscous cresolphthalein-dimethylether. On the basis of the Adam-Gibbs model, the experimental results facilitate the comparison of temperature versus field induced changes in entropy and of their impacts on the dielectric relaxation times. Across six decades of the structural relaxation times, the Adam-Gibbs model provides a good account of the temperature dependence of the dynamics, while a comparable amount of field induced total entropy change leads to a four-times smaller effect regarding the change of time constants. For this material, only a small fraction of the total entropy change that originates from strongly polarizing the sample appears to be relevant for the dynamics in the sense of Adam-Gibbs.