Check of the temperature- and pressure-dependent Cohen–Grest equation

doi:10.1016/S0009-2614(00)00185-8

Chemical Physics Letters

Volume 320, Issues 1–2, 31 March 2000, Pages 113-117

https://doi.org/10.1016/S0009-2614(00)00185-8 Get rights and content

Abstract

The dynamics of a fragile glass-former (diglycidyl ether of bisphenol-A) has been studied by wideband dielectric spectroscopy down to the temperature-induced and the pressure-induced glass transition. A full check of the temperature and pressure dependence of the structural relaxation time, predicted within an extended free volume model by the generalised Cohen–Grest function, is reported. From our investigation it is evident that this function suitably describes the structural relaxation time at ambient pressure, but on the other hand, it strikingly fails in describing the isothermal data under variable pressure.

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Acknowledgements

This work has been partially funded by Ministero dell'Università e della Ricerca Scientifica e Tecnologica (MURST), Italy. One of the authors (M.P.) is grateful to the Council for Scientific Research (KBN), Poland, for financial support (project 2 PO3B 030 12).

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Check of the temperature- and pressure-dependent Cohen–Grest equation

Abstract

Section snippets

Acknowledgements

J. Non-Cryst. Solids

Z. Phys. B

J. Chem. Phys.

J. Chem. Phys.

Phys. Rev. E

Phys. Rev. Lett.

Macromolecules

Phys. Rev. B