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Information × Registration Number 0217U007051, 0115U002654 , R & D reports Title Analysis of thermodynamic and morphological parameters of films of substituted hydrocarbons on the liquid / vapor nterface popup.stage_title Head Kartashinska Olena Sergiyvna, Registration Date 29-12-2017 Organization Donetsk National Technical University popup.description2 Complex studies of thermodynamic and structural parameters of film formation of non-ionic surfactants on the water/ ir and water/alkane interface have been carried out. In the framework of the quantum-chemical model, the values of the clusterization threshold for mono- and disubstituted alkanes: aliphatic and mono-oxylated alcohols, amides of carboxylic acids, alpha-hydroxy acids and N-acyl substituted alanine on the water/air interface were estimated. Clusterization of these surfactants is possible for compounds containing at least 11-16 carbon atoms in the alkyl chain under standard conditions. It was found that the clusterization of nonionic surfactants on the water/air interface is purely a quantum effect. The threshold of the film formation is due not to the solubility of surfactant in water, but to the electron-donor and electron-acceptor properties of functional groups and quadratically depends on the constants of the substituents. The quadratic dependence of the threshold of self-clustering of non-ionic surfactants on the threshold of solubility is revealed. On the basis of quantum-chemical calculations, it was shown that the tilt angle of hydrocarbon chains in monolayers of regarded compounds with respect to the normal to the interface does not change continuously but accepts a number of discrete values depending on the structural peculiarities of intermolecular CH ••• HC-interactions arising between molecules in the monolayer. On the basis of the calculated data obtained using the PM3 method in the framework of the developed quantum-chemical model for different temperatures, it was found that with increasing temperature and decreasing the length of the hydrocarbon chain of surfactant, the content of infinite "linear" 1D clusters increases, which leads to the branching of the monolayer. For the first time in the framework of the quantum-chemical semiempirical method of PM3, the peculiarities of the clustering of gaseous alkanes on the aqueous surface in the presence of aliphatic alcohols were investigated. The superposition-additive approach, developed and tested earlier by the example of monofunctional nonionic surfactants, was modernized and used to calculate the thermodynamic parameters of formation and clusterization of surfactants containing two functional groups. Product Description popup.authors Карташинська Олена Сергіївна Когтєва Ольга Павлівна Осідзе Юлія Володимирівна Таран Надія Анатоліївна Швець Ігор Іванович popup.nrat_date 2020-04-02 Close