In this thesis, the alignment characteristics of nematic liquid crystals were studied.
The pretilt angle and the surface anchoring energy generated in the nematic phase of various liquid crystals aligned on rubbed side chain liquid crystalline polymer film were measured. The relationship between the bulk properties of nematic liquid crystals and their pretilt angles was investigated. Also the relationship between the surface anchoring energy and the bulk properties of nematic liquid crystals aligned on rubbed side chain liquid crystalline polymer(LCP100) film was investigated.
It has been found that the dielectric properties of nematic liquid crystal is the best correlated parameter for the pretilt angle and the surface anchoring energy. And then, the temperature dependence of the pretilt angle and the surface anchoring energy was investigated. The thermal hysteresis of pretilt angle and optical phase retardation is seen near the glass transition temperature of side chain liquid crystalline polymer in heating and cooling process. This phenomenon may be due to the change of surface aligning characteristics of side chain liquid crystalline polymer film.
Finally, the measurement of the dielectric constant of nematic liquid crystal and liquid crystalline polymer was performed in accordance with temperature variation. In this experiment it was found that the thermal variation of the dielectric constant of nematic liquid crystal is strongly correlated with pretilt angle and nematic order parameter.
