Determination of unfrozen water content by DSC

Unfrozen water was divided into two groups by measurements using DSC (differential scanning calorimetry). One is nonfreezable water which does not change the phase with liberation of latent heat and the other is freezable water which crystallizes with latent heat. The content of the former, W n fw, was related to the specific surface area, S, of a specimen, as W n f w = 3.2 x 10 -I+ S. The influence of temperature on the heat of fusion of ice to become a freezable unfrozen water was presented by the relation L(θ) = 7.3θ + 334, where θ was the temperature in degrees C. Two methods were proposed then for the determination of the total content of the two unfrozen water, one when the latent heat of fusion of ice was constant and the other when it was not. This content was measured for a Morin clay by both methods; and curves of this content vs. temperature were examined against the data obtained by other workers for the same clay.