Binary Glass-Forming Materials: Mixtures of Sorbitol and Glycerol

J. Phys. Chem. B, 108 (29), 10451 -10456, 2004. 10.1021/jp031366b S1089-5647(03)01366-X
Web Release Date: April 23, 2004

Binary Glass-Forming Materials: Mixtures of Sorbitol and Glycerol

Kalyan Duvvuri and Ranko Richert*

Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604

Received: December 31, 2003

In Final Form: March 3, 2004

Abstract:

The dynamics of sorbitol/glycerol mixtures across the entire composition range has been characterized by dielectric relaxation measurements for frequencies between 10 mHz and 10 MHz. We explore the gradual change in the glass transition temperature (T_g), fragility (m), nonexponentiality (_KWW), and occurrence of a secondary Johari-Goldstein type relaxation as a function of the mole fraction. Regarding the crystallization tendency at room temperature and the freezing of molecular motion below T_g, these mixtures differ qualitatively from aqueous solutions of sugars or other polyols.

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