title: Thermal and Photochemical Control of Molecular Orientation of Azo-Functionalized Polymer Liquid Crystals and Application for Photo-Rewritable Paper.
abstract: A photo-responsive multi-bilayered film consisting of azobenzene polymer liquid crystals (PA6Az1) and poly(vinyl alcohol) (PVA) has been prepared on a glass substrate by alternate spin coating of the polymer solutions. The reflectivity of the multi-bilayered film disappears by annealing at 80 °C. The disappearance of the reflection by the annealing is related to the thermal out-of-plane molecular orientation of PA6Az1 even in the multi-bilayered film, which leads to a very small difference in refractive indices between PA6Az1 and PVA. The reflectance of the multi-bilayered film is increased again by UV irradiation because of the transformation from the out-of-plane orientation to an in-plane random orientation. In this way, on-off switching of the reflection is achieved by combination of the thermally spontaneous out-of-plane molecular orientation and following photoisomerization of PA6Az1 comprising the multi-bilayered film.
authors: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, Kumamoto 860-8555, Japan.
authors: Masaki
authors: M
authors: Moritsugu
authors: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, Kumamoto 860-8555, Japan.
authors: Takeru
authors: T
authors: Ishikawa
authors: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, Kumamoto 860-8555, Japan.
authors: Tetsuro
authors: T
authors: Kawata
authors: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, Kumamoto 860-8555, Japan.
authors: Tomonari
authors: T
authors: Ogata
authors: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, Kumamoto 860-8555, Japan.
authors: Yutaka
authors: Y
authors: Kuwahara
authors: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, Kumamoto 860-8555, Japan. kurihara@gpo.kumamoto-u.ac.jp.
authors: Seiji
authors: S
authors: Kurihara
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry*; D010209:Paper; D055668:Photochemical Processes; D011142:Polyvinyl Alcohol / Q000737:chemistry*
chemical_list: D001391:Azo Compounds; D011142:Polyvinyl Alcohol