Relative magnitude of the orientational order of liquid crystal (LC) molecules at the (polymer/LC) interface against that in the bulk phase was evaluated by two different methods. One was an indirect method based on the statistic phenomenological theory by measuring the difference between the nematic-isotropic phase transition temperatures (TNI) at the interface and that in the bulk phase. The other was a rather direct method based on the optical second-harmonic generation (SHG) technique that could evaluate the orientational order of the LC molecules contacting with the substrate surface. Qualitative agreement was obtained for the results of interfacial order of the LC molecules from these two methods. The orientational order of LC molecules at the (polymer/LC) interface was strongly dependent upon the difference of interfacial energy between the polymer and LC molecules.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)