Relaxational transitions and ergodicity breaking within the fluid state: the sugars fructose and galactose

Jiang Fan, Charles Angell

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

We describe calorimetric and other studies of time-dependent proceses in some molecular liquids in which there is a higher level of complexity than normally encountered in viscous liquid studies. Best characterized is the sugar d-fructose, which melts to give a liquid which is not in an equilibrium state, and in which slow relaxation processes occur in the liquid far above Tg. These have time scales up to 10 orders of magnitude longer than the shear relaxation time, yet are shown to have an important effect on the liquid viscosity and hence on the value of Tg. Three different heat capacity anomalies are identified, and are assigned to three possible tautomerization equilibria, one of which provides a major contribution to Cp and becomes slow not far below the melting point. The effects of this slow degree of freedom on liquid behaviour are discussed.

Original languageEnglish (US)
Pages (from-to)9-30
Number of pages22
JournalThermochimica Acta
Volume266
Issue numberC
DOIs
StatePublished - Nov 15 1995

Fingerprint

galactose
Fructose
sugars
Galactose
Sugars
Fluids
fluids
Liquids
liquids
Viscosity of liquids
Relaxation processes
Relaxation time
Specific heat
Melting point
melting points
degrees of freedom
relaxation time
specific heat
viscosity
anomalies

Keywords

  • Ergocity
  • Fructose
  • Galactose
  • Relaxation
  • Transition

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Condensed Matter Physics
  • Instrumentation

Cite this

Relaxational transitions and ergodicity breaking within the fluid state : the sugars fructose and galactose. / Fan, Jiang; Angell, Charles.

In: Thermochimica Acta, Vol. 266, No. C, 15.11.1995, p. 9-30.

Research output: Contribution to journalArticle

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