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Information × Registration Number 0211U002484, 0110U004580 , R & D reports Title Hybrid organic-inorganic nanoadsorbents - improvement of the synthesis and development of their production technology popup.stage_title Head Zub Yuriy Leonidovych, Registration Date 10-02-2011 Organization Institute of Surface Chemistry of the National Academy of Sciences of Ukraine popup.description2 Electronic and spatial structure of trifunctional silanes - precursors of sol-gel and template methods of hybrid organic-inorganic nanosorbents synthesis - were established by using quantum-chemical calculations. The obtained results, in the first place the optimized geometry of molecules, are the first steps in studying of the hydrolysis mechanisms as well as mechanism of alkoxysilanes (which have complexing groups) condensation. The same method was used for analysis of the conformational behaviour of calix[4]arene-crown-6 derivatives. This method allows to make a conclusion that there is a relationship between volume, length of spacers that are inserted in position 2 and 4, their character (bridged or unabridged) and conformation of macrocycle molecules. Under condition of some specific substituent's usage, the conformational changes are observed even in crown-6-ethereal fragment of macrobicyclic molecule. Volumetric spacers usually fix calix[4]arene-crown-6 in the conformation of the 1,3-alternate. In this case the preservation of selectivity sorbents, that are based on macrobicycles, becomes possible to such ions as caesium. Thus, calixarenes conformational analysis, performed by quantum-chemical calculations, allowed to predict the optimum composition of alkoxysilyl substituents that will facilitate their choice in synthesis of functionalized macrocycle-precursors. On the grounds of the results of quantum-chemical calculations of fragments and clusters that simulate of presence of T2 and T3 structural units in the surface layer of hybrid sorbents, the conclusion was made about the state of the surface layer in such materials and about the features of its behavior. It was shown that under the presence of water the formation of hydrogen bond should be expected. The hydrogen atom of silanol group and nitrogen atom of amine group take part in this bond. Molecule of water acts as a bridge in this formation. Removment of water from the surface of the sorbents leads to destruction of the bridge and to the formation of new hydrogen bonds - between the amine groups. The spherical particles of silica that contain thiourea and phosphine oxide groups were synthesized by application of the developed techniques, including modified Schtober method. For comparison we should mention that the spherical sorbents with phosphine oxide functional groups were obtained by using the spray-drying method. The morphology of the obtained hybrid materials was studied by SEM and TEM, and their identification was made by using IR spectroscopy, solid-state NMR spectroscopy and other physical methods. All of the obtained hybrid sorbents are promising for application in sorption technology, chromatography, catalysis and medicine. Product Description popup.authors Ільченко М.М. Гончарик В.П. Григор'єва О.П. Дударко О.А. Кожара Л.І. Мельник І.В. Назарчук Г.І. popup.nrat_date 2020-04-02 Close