Thermodynamics Research Center / ThermoML | Thermochimica Acta

The slow molecular dynamics in amorphous probucol

Mora, E.[Elsa], Diogo, H. P.[Herminio P.], Ramos, J. J. M.[Joaquim J. Moura]
Thermochim. Acta 2014, 595, 83-88
ABSTRACT
The slow molecular mobility in the active pharmaceutical ingredient probucol was studied by Thermally stimulated depolarisation currents (TSDC) in the temperature region between 130 and 50 C. The distribution of relaxation times was characterized for the secondary relaxations and for the glass transition relaxation. Based on aging results we were able to draw distinctions between the fast secondary relaxation on the one hand, and the slow-b or Johari Goldstein relaxation on the other. The steepness index of probucol was calculated from the temperature dependent relaxation time of the glass transition and using methods based on the influence of the scanning rate on the glass transition signal (in DSC and TSDC). The obtained values show some scattering but they are in the frontier between the fragile and strong behaviors.
Compounds
# Formula Name
1 C31H48O2S2 probucol
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • Normal melting temperature, K ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1
  • POMD
  • 1
  • Molar enthalpy of transition or fusion, kJ/mol ; Crystal
  • Crystal
  • Liquid
  • Air at 1 atmosphere
  • DSC
  • 1
  • POMD
  • 1
  • Triple point temperature, K ; Glass
  • Glass
  • Liquid
  • Air at 1 atmosphere
  • DTA
  • 1