Hierarchical Striped Walls Constructed by the Photopolymerization of Discotic Reactive Building Blocks in the Anisotropic Liquid Crystal Solvents

A triphenylene-based reactive mesogenic molecule (abbreviated as HABET) was newly designed and synthesized as a programmed building block to construct the striped walls by the photopolymerization in the anisotropic liquid crystal (LC) solvents. On the basis of thermal, scattering and microscopic analyses, it was found that HABET formed three ordered structures: a columnar hexagonal LC phase (Φ_H), a tilted columnar hexagonal LC phase (Φ_T) and a highly ordered columnar oblique crystal phase (Φ_OK). The microscopic molecular orientations in the hierarchical superstructures were controlled in the anisotropic LC solvents with the help of surface anchoring forces, while the dimensions of the striped wall morphologies were determined by the patterned photomasks. The long axis of self-assembled columns in the striped walls was perpendicular to the surface alignment direction regardless of the photomask direction. Additionally, it was realized that the shapes of water drops as well as the surface water contact angles can be tuned by the hierarchical superstructures and morphologies of the polymerized HABET networks. The anisotropic hierarchical superstructures and morphologies concurrently fabricated during the polymerization in the anisotropic LC medium can offer a potential pathway for liquid transportation in the microfluidic devices.