Aspects of the glass transition behaviour of mixtures of carbohydrates of low molecular weight.

The glass transition temperature (Tg) values for carbohydrates alone and in binary mixtures have been determined using differential scanning calorimetry. The Tg of the carbohydrate depends strongly on molecular weight and less on structure. The Tg of the binary mixtures was dependent on composition and, in most instances, was linear with respect to mole fraction. The effect of water on depressing the Tg of the carbohydrates and their binary mixtures was also evaluated. The observed behaviour was compared with that predicted from a thermodynamic approach.