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

Abstract

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.

Polymeric fibers and microporous films by photo‐crosslinking of triphenylene‐derived liquid crystals

“…Gin et al polymerized LC molecules to prepare a hexagonally ordered polymer nanocomposite . Recently fixation of well‐ordered columnar LC molecules collects further interests of many researchers and highly functional polymer materials have been prepared by various reactions like photo‐initiated radical polymerization 12 γ‐irradiation, thiol‐ene reaction, ring‐opening reaction, and metathesis …”

“…We have worked on the development of several discotic LCs and studied their thermal, mesomorphic, and charge transport properties . Considering the structural features and the applicability of the columnar LCs, the next challenge is to fix the oriented discotic molecules in the structure and enhance their properties as reported previously . If the ordered columns are covalently connected along the molecular axis and plane, polymeric fibers or films should be formed depending on the macroscopic shape, and they could be applied as polymeric conducting wires or layers.…”

Programmed Hierarchical Hybrid Nanostructures from Fullerene‐Dendrons and Pyrene‐Dendrons

“…The changes in enthalpy during the cooling process coincide with those obtained in the subsequent heating process (Figure a). As the cooling rate increases, the onset temperatures of exothermic phase transitions move to lower temperatures with reduced heat energy (Δ H ), corresponding to the supercooling effect (Figure S4, Supporting Information) …”

Self-Assembled Hierarchical Superstructures from the Benzene-1,3,5-Tricarboxamide Supramolecules for the Fabrication of Remote-Controllable Actuating and Rewritable Films

“…The optical images show the fan-shaped focal conic texture at the 160 °C (Figure 1d), which is often observed in a typical columnar LC phase. 23,24 Further decreasing the temperature to room temperature results in the solidification with birefringent defects (Figure 1e) which are mainly generated due to the anisotropic volume shrinkages. The POM results combined with those of DSC reveal that three ordered phases are formed below the isotropization temperature (T i = 206 °C): a lowordered LC phase, a highly ordered LC (K LC ) phase, and a crystal (K Cr ) phase.…”