INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
Diffusion-viscosity decoupling in supercooled glycerol aqueous solutions
J. TREJO GONZALEZ; M. PAULA LONGINOTTI; CORTI H. R.
JOURNAL OF PHYSICAL CHEMISTRY B
American Chemical Society
Lugar: Washington; Año: 2015 vol. 119 p. 257 - 257
The diffusion of ferrocene methanol in supercooled glycerol-water mixtures has been measured over a wide viscosity range, which allowed analyzing the composition dependence of the Stokes-Einstein breakdown (diffusion-viscosity decoupling). The observed decoupling exhibits acommon behavior for all studied compositions (glycerol mass fractions between 0.7 and 0.9), determined by the reduced temperature (T/Tg) of the mixtures. This result differs from that reported previously for the diffusion of glycerol in its aqueous solutions, where the reducedtemperature for the decoupling decreases with increasing water content. We conclude that the contradictory results are only apparent, and they can be explained by the use of inconsistent extrapolated values of the viscosity of the glycerol-water mixtures in the supercooled region.