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Toward broadband mechanical spectroscopy.

ABSTRACT: Diverse material classes exhibit qualitatively similar behavior when made viscous upon cooling toward the glass transition, suggesting a common theoretical basis. We used seven different measurement methods to determine the mechanical relaxation kinetics of a prototype molecular glass former over a temporal range of 13 decades and over a temperature range spanning liquid to glassy states. The data conform to time-temperature superposition for the main (alpha) process and to a scaling relation of schematic mode-coupling theory. The broadband mechanical measurements demonstrated have fundamental and practical applications in polymer science, geophysics, multifunctional materials, and other areas.

SUBMITTER: Hecksher T

PROVIDER: S-EPMC5565458 | biostudies-other | 2017 Aug

REPOSITORIES: biostudies-other

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Toward broadband mechanical spectroscopy.

Hecksher Tina T Torchinsky Darius H DH Klieber Christoph C Johnson Jeremy A JA Dyre Jeppe C JC Nelson Keith A KA

Proceedings of the National Academy of Sciences of the United States of America 20170801 33

Diverse material classes exhibit qualitatively similar behavior when made viscous upon cooling toward the glass transition, suggesting a common theoretical basis. We used seven different measurement methods to determine the mechanical relaxation kinetics of a prototype molecular glass former over a temporal range of 13 decades and over a temperature range spanning liquid to glassy states. The data conform to time-temperature superposition for the main (alpha) process and to a scaling relation of ...[more]

PMID: 28765374

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