ИСТИНА

Among the numerous new liquid crystalline (LC) polymers studied in the past decades photochromic LC polymer systems constitute the most important segment in polymer science associated with creation of smart materaisl capable of being highly sensitive to the light irradiation. The first part of the work is devoted to the creation of the novel type of photo-mechanical actuators based on the stretched porous PE films filled with azobenzene-containing photopolymerizable nematic diacrylates. These monomers are oriented by the walls of the PE film pores forming oriented network threaded all polymer sample. Azobenzene fragments of such hybrid PE composite films can undergo E-Z-E photoisomerization of under UV and visible light irradiation. As a result the fast completely reversible bending of the composite films is observed. The obtained light-driven actuators are promising for creation of a novel type of photomobile polymers. The second part of the work deals with the optical and structural studies of chiral-photochromic LC systems (cholesteric oligomer cyclosiloxanes doped by azobenzene compound) using the combined POM and AFM technique. It was found the considerable difference in surface topology of the slowly-cooled and quenched oligomer films. The former samples are characterized by a large number of “valleys” with spiral structure, the latter ones form the spiral superstructured “hills”. The unusual photoinduced processes taking place in these samples caused by polarized light irradiation (532 nm) and accompanied by the structural transformations and directional mass-transport of chromophores and mesogens are discussed in detail. Acknowledgements. This research was supported by the Russian Foundation of Fundamental Research (11-03-01046a, 12-03-00553-а and 11-03-12054-OFI-M). [1] A. Bobrovsky, K. Mochalov, A. Chistyakov, V. Oleinikov, V. Shibaev, Macromol. Chem. Phys. 2012, 213, 2639. [2] A. Ryabchun, A. Bobrovsky, J. Stumpe, V. Shibaev, Macromol. Rapid. Commun. 2012, 33, 991.