The thermal behaviors of Pyro-and Tripoly-phosphate solutions and its freeze-dried solid were investigated using DSC. In this study, ATP related compounds, which are similar on structure to tripolyphosphate, were also investigated. It was found that every phosphate solution system is freeze-concentrated, and finally not precipitate but turns to glassy state. And also, its freeze-dried samples were in glassy state. From moisture dependence of their glass transition temperature, the state diagrams, including glass transition line, were constructed. The glass transition temperatures Tg' (-15℃〜-39℃) of their maximum freeze concentrated solution were found to be relatively higher in comparison with those of sugar solutions.
