Photoalignment and patterning of nanostructures in liquid crystalline thin films

Abstract

Thin films of organics/silica nanohybrids synthesized on a substrate have been subjects of extensive investigation. In general, however, the nanostructures of the thin films are aligned only at local levels, but are randomized at larger scales. Development of alignment methods for such nanostructures at larger scales is of great demand to extend applications. We report herein newly developped methods for macroscopic alignment and micropatterning of nanohybrid films synthesized on a photo-crosslinkable liquid crystalline polymer thin film. Two topics are included: First, the photoalignment of ordinary templating systems of 2D hexagonal liquid crystalline surfactant micelles. Mesostructured organic/inorganic hybrid materials are widely studied. Here, the method of photoaligning and characterizations of the resulting materials will be presented. Second, the photoalignment of chromonic columnar liquid crystal of dye aggregates. We have newly developed a procedure to synthesize a nanohybrid consisting of chromonic liquid crystal and silica network. This new type of chromonic nanohybrids is also found to be aligned by the identical photo-crosslinkable polymer film.