Solubility of the nematic liquid crystal E7 in supercritical carbon dioxide

The solubility of E7, a nematic liquid crystal mixture, in supercritical carbon dioxide (scCO₂) was measured using a static analytical method at (313.15, 323.15, and 333.15) K and at pressures up to 19 MPa. Samples from the CO₂-rich phase were analyzed using a simple but selective reversed-phase high performance liquid chromatographic method. The results indicate unambiguously that scCO₂ can fractionate the mixture toward the E7 components at relative low pressures. Due to the lack of thermodynamic data, the solubility data were correlated using the equation of Chrastil. The results obtained are important for the design and development of polymer-dispersed liquid crystals using supercritical fluid technology.