Phase Diagram of Mixed Mesomorphic Benzylideneanilines — MBBA/EBBA
The crystal-nematic transition of binary mixtures of MBBA and EBBA is strongly sensitive to thermal history. A metastable phase (β-phase) has a eutectic-like minimum melting point of about -14°. However, a sample maintained at -18°C for about one day -will convert to a stable phase (α-phase) with a minimum melting temperature of 13°C. The stable phase seems to be a solid solution. The crystal-nematic latent heat of transformation LKN for the α-phase is linearly dependent on concentration, but that for the β-phase has a minimum, The concentration-dependence of the nematic-isotropic transition temperature is similar to that reported elsewhere for other systems. The nematic-isotropic latent heat of transition is essentially linearly dependent on concentration.
KeywordsDifferential Scanning Calorimetry Metastable Phase Melting Behavior Adiabatic Calorimetry Differential Scanning Calorimetry Peak
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