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Information × Registration Number 0212U000337, 0110U006261 , R & D reports Title Studying of optical properties of nanomaterials on the base of liquid-crystal media with carbon nanotubes and other nanoparticles by the methods of singular optics for assignment and investigation of mechanisms of their interaction with electromagnetic radiation including optical vortices generation, preparation of the methods of nanomaterials complex diagnostics and certification, establishment of time variations of their characteristics. popup.stage_title Head Soskin M.S., Registration Date 01-02-2012 Organization Institute of physics NASU popup.description2 The paper presents the results of a comprehensive study of the dynamics of processes samoagregatsii nanoparticles dispersed in liquid crystal matrices of size and shape. An experimental study of the complex include the following areas: studies of the microstructure, electrical conductivity and phase transitions, the study of physico-chemical properties (differential scanning calorimetry, spectrophotometry), the study of optical properties of the methods of singular optics and Stokes polarimetry. Hybrid liquid crystal composites were filled with multiwalled carbon nanotubes (NTs), organosilicate nanoplastinkamy NPs (organomontmorilonit OMMT and organolaponit LapO). As a liquid crystal dispersion media used nematics EBBA (4 etoksibenziliden-4'-n-butylaniline) and 5CB (4-pentyl-4'-cyanobiphenyl). The concentration of NTs and NPs ranged from 0.0 to 4% by weight. There have been various mechanisms for restructuring composite 5CB + NTs and 5CB + NTs + LapO during heat incubation. Showed the presence of strongly homogeneous structure of the composites. Found patterns of thermograms (obtained by the methods of differential scanning calorimetry) and spektrofotometrnichnih manifestation of aggregation of different types of nanotubes. The character of the stabilizing effect of particles on the other anizometrii aggregation processes of liquid crystal dispersions of nanotubes. It is established that the transition layer perturbed Fredericks in a liquid crystal having inverted wall. It is shown that the optical field, which occurs when light passes through the nanocomposite, there are points of circular polarization (C points). The origin and movement of these points reflects changes in the orientation of the liquid crystal matrix. The results of polarization studies are confirmed by direct measurements of transparency of composites using a Monte Carlo estimate is made depending on the concentration of percolation in composite systems filled with partially ordered cylindrical particles. Also built a molecular model compounds and aggregation of carbon nanotubes in the nematic LC environment, taking into account the geometry of the nanotubes (odnostinkovi bagatostinkovi and with different aspect ratio). The proposed model of self-organization of nanoparticles in the hybrid composites, which explains the difference in filling LapO and OMMT. Product Description popup.authors Васильєв Василь Ігоревич Поневчинський Владіслав Вікторович Соскін Марат Самуїлович popup.nrat_date 2020-04-02 Close