Glass transitions in molecular liquids. I. Influence of proton transfer processes in hydrazine-based solutions

As a first stage in a study of the physicochemical consequences of proton-transfer processes in solutions, the composition regions of a number of protonic acid + hydrazine binary systems in which macroscopic samples can be obtained in the vitreous state have been determined. The glass transition temperatures T_g within these regions have been determined, and are compared with those determined for solutions in the Ca(NO₃)₂ + CH₃NH₂ system. Correlations of the magnitude of T_g at a given composition with hydrogen-bonding ability and basicity of the anion are presented. In addition, the glass temperatures of structurally related small-molecule liquids are presented and an interpretation of the relative magnitudes of T_g values in terms of structural and molecular interaction parameters is given. Also presented are the "ideal" glass transition temperatures, T₀, for these liquids predicted from thermodynamic data, and the consistency of T_g values with these predicted T₀ values is discussed.