Phase Separating Morphology of Liquid Crystalline Polymer/Flexible Polymer Blend

The phase-separation kinetics of liquid-crystalline polymer/flexible polymer (LCP/FP) blend wa studied with the coupled time-dependent Ginzberg-Landau equations for compositional order parameterand orientational order parameter Sij, which were numerically solved by means of the cell dynamical system in two dimensions. The influence of coupling between compositional and orientational ordering processes on the phase separating morphology was investigated. It was found that the orientational ordering promoted the compositiona ordering, i.e., the increasing of the magnitude of orientational order equaled the decreasing of the compatibility between two phases. Moreover, the spatial distribution of phase-separated structures is determined by both the thermodynamic factor, which means the nematic direction of LCP domains parallel to the interface is preferable, and kinetic factors, which imply LCP has a tendency to diffuse parallel to the nematic direction. The small-angle light scattering patterns are numerically reproduced by means of the optical Fourier transformation of spatial variation of the polarizability tensoraij, and the azimuthal dependence of the scattering intensity distribution i interpreted.