Isothermal enthalpy relaxation of glycerol

• The isothermal enthalpy relaxation of glycerol has been measured at 13 different annealing times at temperatures of 170, 175, 180, and 185 K. The glasses were formed by linear cooling at 0.667 and 0.083 K·s−1 in a differential scanning calorimeter (DSC). The Williams-Watts relaxation function was fitted to data of enthalpy versus time. A strong temperature dependence was found for the relaxation time. The distribution parameter, β, showed an increase from 0.49 at 170 K to 0.65 at 185 K. We also found indications of an enthalpy dependence in β. Comparison with a theory of volume relaxation showed differences between rates of volume and enthalpy relaxation.

Ämnesord

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Nyckelord

Differential scanning calorimetry

glycerol

enthalpy

relaxation

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