抄録
The amounts of three different types of water adsorbed on polymers containing hydrophilic groups were determined by differential scanning calorimetry (DSC). The first type is non-freezing water the glass transition of which was detected in DSC. The second type corresponds to a kind of bound water, which was detected as a crystallization peak in the vicinity of 225K (Peak II). The peak appeared when the water content exceeded the critical amounts of non-freezing water. The enthalpy of the crystallization of Peak II increased gradually with increasing water content and then saturated at a certain amount of water. The third type is free water, the crystallization peak (Peak I) of which was found at the same temperature of that of pure water.
From the enthalpies of the crystallization of the above two peaks and the known weight of adsorbed water, it is possible to calculate the quantities of both free water (Peak I) and bound water (non-freezing+Peak II).
