Spatial distribution control of polymer nanoparticles by liquid crystal disclinations

Abstract

A perylene-labeled hyper-branched polymer with a mesogenic shell was observed to migrate toward a field with a large distortion of directors. This polymer was captured by disclination lines of 1/2 strength in its nematic and chiral nematic phases using a confocal fluorescence microscope. In particular, the well-aligned particle array of the hyper-branched polymers was produced by the chiral nematic phase confined in a wedge cell. The hyper-branched polymer with its mesogenic shell was completely dissolved into an isotropic phase. Immediately after a phase transition to the chiral nematic phase, numerous droplets appeared over a wide area owing to phase separation, and the free droplets moved toward the disclination lines via Brownian motion. Finally, the droplets were rapidly attracted to the disclination lines and trapped within them. A fluorescent-labeled hyper-branched polymer with mesogenic shell was captured by the disclination lines of a liquid crystal. In a Grandjean–Cano wedge cell, the particles of the hyper-branched polymer migrated toward the periodically aligned defect line and thus formed a two-dimensional lattice array.