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Scaling out the density dependence of the $α$ relaxation in glassforming polymers

C. Alba-Simionesco·A. Cailliaux·A. Alegria·G. Tarjus
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Abstract

We show that the density and temperature dependences of the $α$-relaxation time of several glassforming polymers can be described through a single scaling variable $X=e(ρ)/T$, where $e(ρ)$ is well fitted by a power law $ρ^x$, $x$ being a species-specific parameter. This implies that ``fragility'' is an intrinsic, density-independent property of a glassformer characterizing its super-Arrhenius slowing down of relaxations, and it leads us to propose a modification of the celebrated Angell plot.

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C. Alba-Simionesco, A. Cailliaux, A. Alegria, G. Tarjus. 2004-04-02. Scaling out the density dependence of the $α$ relaxation in glassforming polymers. https://doi.org/10.1209/epl%2Fi2004-10214-6

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