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Information × Registration Number 0217U003102, 0115U003539 , R & D reports Title Creating supramolecular assemblies based surfactants for catalysis and molecular recognition popup.stage_title Head Anatolii F. Popov, Доктор хімічних наук Registration Date 18-01-2017 Organization The L.M.Litvinenko Institute of Physical-Organic Chemistry and Coal Chemistry popup.description2 Objects of research: supramolecular assemblies based on functionalized and cationic surfactants. Nucleophilicity and micellar effects micelle and comicelle systems based on surfactants. Ionic liquids based imidazole, pyridine and tetralkylammonium. Objective: To develop a system based on functionalized surfactant to effectively splitting substrates containing acyl group and solubilisation of hydrophobic molecules, as well as the preparation of a series of ionic liquids, which can biodegradable substrates, which have been mentioned above. Methods: UV spectroscopy; potentiometry; dynamic light scattering; tensiometry; methods IR, 1H NMR, 13C NMR; elemental analysis; general preparative techniques and synthetic chemistry. Was synthesized a series of imidazolium, pyridinium and tetraalkylammonium surfactant functionalized oxime groups. In some cases, standard synthetic schemes are modified, resulting in improved yield and methods for making the compounds more suitable. Investigated protolytic equilibrium in aqueous solutions of these compounds using a potentiometric, spectrophotometric methods and the method of NMR titration. We calculate the the apparent acid ionization constant (pKa app.) surfactants functional group in the individual state and comicelle with cetyltrimethylammonium bromide (CTAB). It is demonstrated that for a series of ammonium and imidazolium surfactants, functional group which does not involve cationic center, pKa, app. functional groups, as in the individual state or in comicelle with CTAB, are practically identical and are independent of the length of the alkyl substituent. For pyridinium and imidazolium surfactant, a functional group which is associated with a cationic center for their comiselle with CTAB compared with individual micelles, observed a decrease in pKa, app. Also for comiselle these surfactants with CTAB, there is a tendency reducing the pKa app. with increasing length of the alkyl substituents. For the imidazolium surfactants and methyl analogues, by NMR titrations acid, studied in detail the processes of acid ionization, demonstrated their stability their in solution. Iinstalled a large mobility amidine protons for surfactants which do not contain substituents in the 2-position imidazolium ring. Studied the reactivity of the gemini imidazolium and tetraalkylammonium surfactants in processes cleavage 4-nitrophenyl diethylphosphate, 4 (NPDEP) and 4-nitrophenyl-4-toluenesulfonate (NPTS). A comparative analysis of their effectiveness. It is shown that as in the case of 4- nitrophenyl diethylphosphanata - (NPDEPN), by cleavage NPDEP and NPTS imidazolium surfactants are more effective than ammonium surfactant (regardless of the level of hydrophobicity and the reactivity of the selected substrate). Spend noncovalent functionalization micelle mono- (CTAB and cetyl dimethyl (2-hydroxyethyl) ammonium [TSGAB]) and dicationic surfactants of type 14-n-14 (where n = 2, 4, 6) and their comiselles the of molecules organic dye alizarin. With the use of polycyclic aromatic compounds of similar structure (naphthalene and anthracene), analyzed the influence of the size of a polycyclic skeleton and the presence of hydrophilic substituents on the effectiveness of the solubilisation and sizes aggregates produced. Based on the spectrophotometric data shows that the gemini surfactant 14-n-14 exhibit greater solubilisation capacity (2-4 times) compared to the monomeric surfactant. Raising solubility of anthracene by increasing the spacer length n occurs in the direction 2 ? 4 ? 6 while naphthalene and alizarin not seen the exact depending solubilisation capacity, on the length of the spacer. It should be noted that for Alizarin depending on the magnitude of solubilisation capacity of the surfactant concentration at high concentrations of the latter, there is a kink, after which the solubilisation capacity is reduced. Method of dynamic light scattering (DLS) demonstrated that the size of aggregates, produced in a solution, it depends how from structure solubilisate, so and the nature and concentration of surfactant. With the use of amino acids - phenylalanine, tyrosine and proline - was obtained a series of ionic liquids containing in its composition pyridinium or imidazolium - ions. Some of them it has quite large, hydrophobic substituents, which allows from them expect the surface activity in aqueous solutions. Prepared samples of the new ionic liquids (including potential surfactant) to conduct of tests on their biodegradability. .5481 Product Description popup.authors Аніщенко В.М. Бєлоусова І.О. Бураков М.І. Гребенюк Л.В. Дикун О.М. Дріжд В.Л. Калафат К.В. Капітанов І.В. Карпічев Є.А. Мітченко О.С. Сердюк Г.О. Фролова І.Б. Чотій К.Ю. Шевчук О.В. Шологон В.І. Шумейко О.Є. popup.nrat_date 2020-04-02 Close