Shaydyuk Y. Optical properties and structure of heterogeneous nanocomposites based on organomodified alumosilicate

The thesis is dedicated to the study of both optical properties and structure of the heterogeneous nanocomposites based on organomodified alumosilicate (the nature montmorillonite clay mineral) and nematic liquid crystal 4'-pentyl-4-cyanobiphenyl (5CB) depending on chemical properties of the surfactant and concentrations of nanoparticles. The surfactant substances such as octadecylbenzyldimethylammonium chloride (OBDM) and dioctadecyldimethylammonium chloride (DODM) are used as the surface modificators in the production of organoclays. Such composites have a set of new structural and optical properties, which have been investigated by IR-spectroscopy, differential scanning calorimetry, X-ray diffraction methods, polarization and atomic-force microscopy. X-ray diffraction method shows the existence of two various types of the interplanar spacing. Investigations of the IR-band spectral parameters allowed to conclude that Van-der-Waals interactions between the components take place. The correlations between the structure formation and optical properties of nematic LC - organoclay mineral nanocomposites are shown. Also it is shown that the chemical nature of modificators determines the character of the organic matrix - inorganic nanoparticles interfacial interactions and electrooptical properties of these composites.