Volume Effects on the Glass Transition Dynamics

C. M. Roland; K. J. McGrath; R. Casalini

doi:10.1016/j.jnoncrysol.2006.02.152

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arXiv · cond-mat/0601388

Volume Effects on the Glass Transition Dynamics

C. M. Roland·K. J. McGrath·R. Casalini

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Abstract

The role of jamming (steric constraints) and its relationship to the available volume is addressed by examining the effect that certain modifications of a glass-former have on the ratio of its isochoric and isobaric activation enthalpies. This ratio reflects the relative contribution of volume (density) and temperature (thermal energy) to the temperature-dependence of the relaxation times of liquids and polymers. We find that an increase in the available volume confers a stronger volume-dependence to the relaxation dynamics, a result at odds with free volume interpretations of the glass transition.

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C. M. Roland, K. J. McGrath, R. Casalini. 2006-01-17. Volume Effects on the Glass Transition Dynamics. https://doi.org/10.1016/j.jnoncrysol.2006.02.152

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