Thermal analysis of solid-solid interactions in binary mixtures of alkylcyclohexanes using DSC

Differential scanning calorimetry (DSC) was used to construct phase diagram s of binary mixtures of alkylcyclohexanes and to characterize metastable ph ases formed in the binary mixtures. The experimentally measured liquidus cu rves were compared to the liquidus curves calculated using ideal solution t heory. The measured phase diagrams of pentadecylcyclohexane/nonadecylcycloh exane and octadecylcyclohexane/nonadecylcyclohexane binary mixtures are con sistent with theoretical phase diagrams constructed based on the assumption that these mixtures form eutectic systems. It was also observed that a met astable phase formed in some binary mixtures of pentadecylcyclohexane/nonad ecylcyclohexane under fast cooling conditions. It is hypothesized that this metastable phase recrystallizes into the eutectic phase upon heating.