Phase Equilibria in Liquid Crystalline Polymer Solutions: Theory and Experiment

We compared various statistical thermodynamic theories with experimental results for isotropic—liquid crystal phase behaviors in many stiff-chain liquid-crystalline polymer solutions. Among the theories, the scaled particle theory for wormlike hard spherocylinders most successfully explained the experimental phase behaviors in neutral polymer systems, and the same theory considering the electrostatic interaction in a perturbative way was favorably compared with a phase diagram for a charged stiff polymer system. Good agreements between this theory and experiment were also obtained for the osmotic pressure and the orientational order parameter of poly(γ-benzyl L-glutamate) solutions.