Thermal analysis of tertiary butyl alcohol/sucrose/water ternary system

Cryo Letters. 2005 Sep-Oct;26(5):289-96.

Abstract

The purpose of this work is to investigate the freezing properties of tertiary butyl alcohol (TBA)/sucrose/water ternary system. Differential scanning calorimetry (DSC) is employed to determine the glass transition temperature of the maximally freeze-concentrated solution Tg' and the crystallization (or devitrification) temperature Tr. DSC measurements show that the presence of sucrose hinders the crystallization of TBA during cooling. The residual TBA in the glassy state will cause a decrease in Tg' and will crystallize during heating. An increase in the cooling rate causes a decrease in Tg'. For 10% TBA/10% sucrose/water ternary system, the critical heating rate is approximately 250 degrees C/min. Annealing treatment at temperatures below Tg' causes the crystallization of TBA, which indicates that TBA molecules still have appreciable mobility even at temperatures below Tg'. When the ratio of TBA to sucrose is less than 0.2, TBA cannot crystallize during cooling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calorimetry, Differential Scanning / methods*
  • Crystallization
  • Differential Thermal Analysis
  • Freeze Drying
  • Sucrose / analysis*
  • Temperature
  • Water / analysis*
  • tert-Butyl Alcohol / analysis*

Substances

  • Water
  • Sucrose
  • tert-Butyl Alcohol