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Vol 11, No 2 (2016)
View or download the full issue PDF (Russian)
https://doi.org/10.32362/2410-6593-2016-11-2

SYNTHESIS AND PROCESSING OF POLYMERS AND POLYMERIC COMPOSITES

5-16 833
Abstract
The review presents schemes for obtaining homologous series of the linear α,ω-carbofunctional oligodimethylsiloxanes with the silicone chain length from 6 to 60 siloxane units containing carboxydecyl, aminopropyl and glycidoxypropyl groups at the chain ends allowing to obtain organosilicon surfactants with reproducible structure and properties. Data on the surfactant colloidchemical properties and kinetic regularities of styrene polymerization in their presence are provided. Systematic research of heterophase styrene polymerization kinetic regularities in the presence of water-insoluble α,ω-carbofunctional oligodimethylsiloxane allowed to formulate the fundamental differences of polymerization kinetic regularities from those observed in the presence of water-soluble surfactants. The mechanism of interfacial adsorption layers formation with water-insoluble α,ω-carbofunctional oligodimethylsiloxanes on the surface of monomer drops and polymer-monomeric particles was considered. This mechanism consists in the forced surfactant replacement by the formed polymer (because of their incompatibility) to the interfacial adsorption layer and in the formation of the surfactant supermolecular structures. The latter in total with the polymer provide its high durability.
17-22 670
Abstract
The article describes research on the development of new diagnostic test systems operating on the basis of latex agglutination reaction, in which polymer microspheres are used as bioligand carriers instead of erythrocytes. Polymeric microspheres to be used as bioligand carriers must satisfy the following requirements: narrow size distribution, diameter of 5 microns. Besides, they must be characterized by aggregative stability in water and buffer solutions and be contained functional groups in the surface layer for linking with the functional groups of the protein. They are crosslinked particles obtained by copolymerization of styrene and divinylbenzene on polystyrene seed particles 1.5 microns in diameter with a narrow size distribution followed by modification by chloromethylation and amination by ethylenediamine. To increase the hydrophilicity of the surface of the polymer microspheres and to reduce nonspecific adsorption of proteins dextran was immobilized on the surface of the particles by covalent binding with amino groups of particles using Maillard reaction. It was found that diagnostic test systems, where modified dextran particles were used as carriers of the bioligand (Vi-antigen), are characterized by insufficient specificity and require additional modification of the surface of the polymer microspheres to eliminate its non-specific interaction with the surface of the polymer plate used for the latex agglutination reaction. A nonionic surfactant (Tween 80) proposed for the surface modification and used in a certain concentration provides the best reaction specificity.

THEORETICAL BASIS OF CHEMICAL TECHNOLOGY

23-30 541
Abstract
Preliminary studies on the initial stage of the development of the industrial process for producing the desired product play a decisive role in choosing the type of raw materials and an efficient catalytic system. These parameters determine the number of possible waste byproducts, the target product purity and the resulting energy costs. In this article we compared the choice of raw materials and catalytic systems for the industrial scale production of benzene-1,2,4,5-tetracarboxylic acid, which is widely used in the production of organic products of great economic importance.
31-37 510
Abstract
Mathematical models were developed for two operational modes of the injector-type extraction column upon separation of the initial mixture. On the basis of a numerical experiment comparison of the cyclic operational mode with the stationary operational mode was carried out with respect to the extraction degree and the energy demand. It was confirmed that, as compared to the stationary operational mode, the cyclic operational mode provides a greater degree of extraction. The ratio of the extraction degrees in these operational modes of the extractor depending on the mass transfer criterion is of an extremal type. The maximum value of this ratio falls within the range from 1 to 4 and is equal to 1.5. It was also shown that the stationary operational mode of the extractor is more energy consuming than the cyclic one. The ratio of the energy demand for the stationary operational mode of the extractor to the energy demand in the cyclic operational mode depends on the extraction degree. This ratio grows from 1 to 5 within the interval of the extraction degree from 0.1 to 0.47.
38-45 743
Abstract
The experimental temperature dependence of the vapour pressures of isobutyl acetate, acetic acid and methyl ethyl ketone were determined, and isobaric vapour-liquid equilibrium data of binary systems of methyl ethyl ketone + isobutyl acetate and methyl ethyl ketone + acetic acid were obtained. The experimental data were processed using the Antoine and Riedel equations and the NRTL and Wilson local composition equations, respectively. Comparison of the experimental and calculated data confirmed the adequacy of the vapour-liquid equilibrium mathematical simulation.

CHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALS

46-49 598
Abstract
Nonahydro-closo-nonaborate anion possess the property of structural nonrigidity because of presence of three low-coordinated boron atoms. So it’s able to come into the reactions of polyhedral extension. This paper is devoted to the reactions of homoatomic polyhedral extension in nonahydrocloso-nonaborate anion [B9H9]2- in presence of triethylaminborane complex BH3·(C2H5)3N. It was shown that mixes of [B10H10]2- and [B12H12]2- salts in various molar ratios had been formed as products. These ratios depend on proportion of reagents. In presence of excess of triethylamin borane complex the molar ratio of products is 1:1. When equimolar amount of triethyamminborane complex used, the selectivity of process shifted to formation of [B10H10]2- anion. However the formation of [B12H12]2- still occurs in this conditions but the molar ratio of [B10H10]2-:[B12H12]2- is 5:1.
50-56 614
Abstract
The paper is devoted to the interaction of copper(II) chloride with water soluble β-furfuraldoxime (N-(furan-2-ylmethyliden)hydroxylamine) in hydrochloric solutions. It was been revealed that the degree of copper(II) precipitation from aqueous solutions and hydrochloric solutions with the pH of 4 M HCl by this reagent is not higher than 52% even when the precipitant is used in abundance. These dependencies has been compared to the similar results of palladium(II) precipitation obtained when all other conditions were equal. It has been discovered that various complexes are formed when Cu(II) reacts with a β-furfuraldoxime and that it depends on the acidity of the solution. In weak acid solutions (0.01-0.1 M HCl) the «green» complex of composition [CuL4Cl2] was obtained and in this complex the oxime is coordinated with the central atom by an oxygen atom of the oxime group. The so-called «red» complex of composition [CuL2Cl2] is formed in the pH range of 1-4 M HCl and in ethanol. In this complex the coordination of ligand molecules is realized by the oxygen atom of the furan ring and by the oxygen of the oxime group. Reagent N-(furan-2-ylmethyliden)hydroxylamine can be used for practical quantitative release of palladium from hydrochloric solutions. However, it does not provide the separation of copper and palladium in their joint presence.
57-65 642
Abstract
The catalytic system Pd (OAc)2-HClO4--CH3CN (AN)-H2O of olefins oxidation was studied. Information about the ways of forming catalytic active cationic palladium complexes was detected. Analysis of the electron spectroscopy data shows the probability of existence complexes [Pd(AN)(H2O)3]2+ (λmax = 360-365 nm), [Pd(AN)2(H2O)2]2+ (λmax = 335-345 nm) in catalytic system. The preparation method of stable and sufficient active catalytic system for obtaining reproducible kinetic data was designed.
66-73 675
Abstract
The conditions for the formation of nanocomposites based on the basis of lattice packings SiO2 nanospheres (opal matrices) with included clusters of crystalline phase of titanium oxide (TiO2 and TiO) and rare-earth titanates of the general formula R2TiO5 or R2Ti2O7, where R - Er, Dy, Gd, Pr, Tb and Yb in interspherical nanospacing are considered. The composition and structure of the nanocomposites studied electron microscopy, X-ray diffraction and Raman spectroscopy. Results of measuring of the frequency dependences of real and imaginary components of the permittivity and microwave conductivity (ranging 10-2-1012 Hz) obtained nanostructures are viewed.

MATHEMATICAL METHODS AND INFORMATION SYSTEMS IN CHEMICAL TECHNOLOGY

74-80 531
Abstract
The article presents fundamentally new results on the analytical theory of thermal conductivity for hyperbolic transport models. The questions of the correct formulation of boundary value problems are considered. A technique for finding exact analytical solutions of a rather complex class of boundary value problems based on the method of Green's functions and operational calculus is developed.
81-85 555
Abstract
The dynamics of active atoms that determine structure phase transitions in a solid body is considered in the context of the previously presented atom interaction model based on a special type of three-minimum potential. Periodical and soliton-like solutions of nonlinear differential equation of motion were obtained. The value of the bond energy of active atoms with respect to the potential barrier height in a single-particle potential with a triple minimum determines the character of a phase transition. Crystals of the MeI MeIIBX4 kind, as well as crystals and metals, on the surface of which atoms of gases and metals are absorbed, are considered as objects, in which the obtained results can be used.
86-91 539
Abstract
The article tells about life and fate of S.Ya. Plotkin, whose 110-th anniversary of birth was marked on March 2016. He was born in 1906 in Melitopole town (Ukraine). Having graduated at the Moscow Institute of Fine Chemical Technology in 1931, he was asked for administration works firstly as the director of the Institute and then as the member of the All-Union Committee for High School problems. During all his life S.Ya. Plotkin successfully combine administrative, scientific, pedagogical and journalistic activities. He was the expert in the problems of hard alloys and powder metallurgy, professor, editor in chief of the journal «History of Natural Sciences and Technique». He was the member of the Journalist’s Union of the USSR, Honorary member of the International Institute for the Sciences of Sintering and Honorary worker of Culture of Russian Federation.


ISSN 2410-6593 (Print)
ISSN 2686-7575 (Online)