Photochromic liquid crystalline

L. V. Natarajan, T. J. Bunning, and S. Y. Kim, Photochromic liquid crystalline cyclic siloxanes containing spiropyran groups, Macromolecules, 27, 7248-7253 (1994). 

V. Fisher, T., Lasker, L., Czapla, S., Riibner, J., and Stumpe, J. Interdependence of photfKirien-tation and thermotropic seif-organization in photochromic liquid crystalline polymers. Mu/. Cryst. Liq. Cryst. 298, 213 (1997). 

Btibrovsky, A., Boiko, N., and Shibaev, V. Photo-optical properties of new combined chiral photochromic liquid crystalline copolymers. Liquid Crystals 25, 393 (1998). 

Chen, X., Xue, Q. B., Yang, K. Z., Zhang, J. Z., and Zhang, Q. Z. Monolayer Behaviours for the Photochromic Liquid Crystalline Copolymers with Azobenzene and Cholesterol Side Groups. Supramol. Sci. 5, 591 (1998). 

Extensive studies on photochromic liquid-crystalline polymers have been made by Krongauz et al,2 Liquid-crystalline phases caused marked colour changes of poly(acrylates)98 and poly(siloxanes) substituted with spiropyran side chains upon UV irradiation owing to the aggregation of the photomerocyanines." In contrast, spirooxazines attached to liquid-crystalline polymer backbones displayed no aggregation and hence exhibited normal photochromism similar to that in solution. Fulgimides bound covalently to the side chains of nematic liquid-crystalline polymers also showed normal photochromism. 

A. S. Angeloni, D. Caretti, C. Cariini, E. ChieUini, G. Galli, A. Altoare, R. Solaro, and M. Laus, Photochromic liquid-crystalline polymers. Main chain and side chain polymers containing azobenzene mesogens, Liq. Cryst. 4, 513-527 (1989). 

T. Fischer, L. Lasker, J. Stumpe, and S. G. Kostromin, Photoinduced optical anisotropy in films of photochromic liquid crystalline polymers, Photochem. Photobiol. A 80, 453 159... 

Fischer T, Lasker L, Czapla S, Riibner J, Stumpe J. 1997. Interdependence of photo orientation and thermotropic self organization in photochromic liquid crystalline polymers. Mol Cryst Liq Cryst 298 213 220. 

We were able to exhibit a variety of the three-dimensional motion in crosslinked photochromic liquid crystalline polymers by controlling the irradiation conditions and thus were able to convert light energy directly to mechanical work. 

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