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Electro-kinetic phenomena (EKP) arising under dc electric field in nanoporous polyethylene terephthalate (PET) films, filled with a nematic liquid crystal (NLC) 4-n-pentyl-4ʹ-cyanobiphenyl (5CB), were investigated for the first time. The volumetric flow rate was found to be directly proportional to the applied voltage U in the range of 0 . . . 30 V for both isotropic and nematic phases. Such type of dependences correspond to quasi-Newtonian behaviour of a liquid crystal (LC) with orientation strongly stabilised by surfaces. The value of zeta potential (about -12 mV) was estimated from the data, obtained in isotropic phase in the approximation of a 'plug' velocity profile. The possible role of electrically induced flows in previously reported electrooptical response of PET films filled with LC is discussed. The obtained results can be used for elaboration of optofluidic devices of a new type.

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The results of investigation of electro-optical properties of porous polyethylene terephthalate films filled with a nematic liquid crystal (5 CB) are presented. It is established that the optical response of the samples on the applied voltage drastically depends on the frequency range. At low frequencies of applied electrical field (ffc) electric field induces an overall change in the light intensity, which is typical for an electro-optical response of a liquid crystal (LC) layer in a conventional "sandwich"-like cell. The dependences of critical frequency fc, threshold voltages, and characteristic times on a pore diameter d were established. The peculiarities of electro-optical effects can be explained in the framework of the approach which connects the variations of light intensity with the corresponding changes of the effective refractive index n(eff) of a composite LC media. The unusual behavior of the electro-optical response at low frequencies is assigned to the orienting action of the specific shear flow typical for electrokinetic phenomena in polar liquids.