Photoinduced Morphological Transformation and Photodriven Movement of Objects Using Self-assembly of Amphiphilic Diarylethene in Water

Abstract

Self-assembly of amphiphilic photochromic diarylethene having tri(ethylene glycol) monomethyl ether chains was examined in water from the viewpoint of photoinduced morphological transformation and photodriven movement of objects. Self-assembled supramolecular architectures of the amphiphilic diarylethenes undergo photoinduced macroscopic morphological transformation upon alternate irradiation with UV and visible light. The photoreversible morphological change can be rationalized as a photoinduced phase transition between the high- and low-temperature phases of the lower critical solution temperature (LCST) transition. By using a depletion force in a methylcellulose aqueous solution, an amphiphilic diarylethene hierarchically assembled into bundled fibers, which showed shrinking of more than 100 μm under visible light irradiation. Linearly polarized light induced anisotropic growth of the assembled architecture and the diffusive motion of added polystyrene beads was suppressed in the perpendicular direction to the polarized light. The movement of many objects tracing the movement of a UV-irradiation spot was achieved with the assistance of the photogenerated supramolecular architecture.