Photoinduced Alignment of Nanocylinders by Supramolecular Cooperative Motions

Chemical Resources Laboratory, Tokyo Institute of Technology, R1-11, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
Journal of the American Chemical Society (Impact Factor: 12.11). 09/2006; 128(34):11010-1. DOI: 10.1021/ja064148f
Source: PubMed

ABSTRACT A linearly polarized laser beam was used to control nanocylinders self-assembled in an amphiphilic diblock liquid-crystalline copolymer consisting of flexible poly(ethylene oxide) as a hydrophilic block and poly(methacrylate) containing an azobenzene moiety in the side chain as a hydrophobic liquid-crystalline segment. The perfect array of poly(ethylene oxide) nanocylinders was achieved, aligned perpendicularly to the polarization direction of the actinic light by supramolecular cooperative motions between the ordered azobenzene and microphase separation. By the simple and convenient way of photocontrol, the macroscopic parallel patterning of nanocylinders can be easily obtained in an arbitrary area.

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