Glasses with strong calorimetric β-glass transitions and the relation to the protein glass transition problem

J. Fan, E. I. Cooper, Charles Angell

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

We describe the heat capacity manifestation of the glass transition in two salts of asymmetrical organic cations in which the glass transition on heating occurs in two distinct stages with roughly equal thermodynamic strengths, ΔCp. The first of these appears to involve side chain motions since it freezes out at the temperature at which a plastic crystal phase of the same compound exhibits the plastic crystal glass transition. The latter is weaker than the liquid-to-glass transition because it involves the loss of fewer degrees of freedom. The behavior is unusual because secondary relaxation in glasses usually has only small excess heat capacity. The behavior is reminiscent of that in proteins in which the glass transition is smeared out over a very wide range of temperatures.

Original languageEnglish (US)
Pages (from-to)9345-9349
Number of pages5
JournalJournal of Physical Chemistry
Volume98
Issue number37
StatePublished - 1994

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Glass transition
proteins
Proteins
Glass
glass
Specific heat
Plastics
plastics
Crystals
specific heat
Cations
Salts
Positive ions
crystals
Thermodynamics
Heating
degrees of freedom
Temperature
salts
Liquids

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Glasses with strong calorimetric β-glass transitions and the relation to the protein glass transition problem. / Fan, J.; Cooper, E. I.; Angell, Charles.

In: Journal of Physical Chemistry, Vol. 98, No. 37, 1994, p. 9345-9349.

Research output: Contribution to journalArticle

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