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Vol 13, No 5 (2018)
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https://doi.org/10.32362/2410-6593-2018-13-5

THEORETICAL BASES OF CHEMICAL TECHNOLOGY

5-13 131
Abstract
Mesityl oxide is an important product of organic synthesis, which is used in the manufacture of pharmaceuticals and as a solvent. The demand for mesityl oxide is growing, which determines the need for further improvement of its production. The disadvantages of the traditional methods of obtaining mesityl oxide are low values of reagent conversion and selectivity. To eliminate them, it is proposed to obtain mesityl oxide in a combined reaction-rectification process. The combination of chemical transformation and separation of the resulting reaction mixture by means of rectification in one apparatus allows for a continuous withdrawal of the formed products from the reaction zone, which increases the rate of the target reaction, conversion and selectivity. In accordance with the modern strategy for the development of chemical-technological processes, the collection and processing of physical and chemical information on the properties of the components and mixtures contained in the reaction system was performed. Based on the experimental data, the parameters of the phase equilibrium model are determined, and its adequacy is estimated. The phase equilibrium model was used to construct a distillation diagram, to verify its consistency, and to conduct computational studies of the reaction-rectification process. The thermochemical parameters of the target reactions are calculated, the equilibrium constants are determined, and their temperature dependence is established. On the basis of the analysis of the literature data, a kinetic model of the process is proposed, and the conditions favorable for the course of the desired chemical transformation are determined with the use of this model. The obtained data are necessary for carrying out the analysis of the statics, constructing the basic technological scheme and calculating its static parameters.

CHEMISTRY AND TECHNOLOGY OF MEDICINAL COMPOUNDS AND BIOLOGICALLY ACTIVE SUBSTANCES

14-22 153
Abstract
This work is devoted to optimization of the synthesis of γ-S-carboxyethyl monomers of PNA based on L-Glu. PNA are promising compounds that hybridize with DNA or RNA, and due to their properties they are used in molecular biology, personalized medicine, and can also be used to create nanomaterials. To increase the yield of the desired monomers, it has been proposed to replace the benzyl protecting group with the carboxy function of the side radical by cyclohexyl one. Two synthetic schemes were proposed. In the first of them, γ-benzyl-N-Boc-glutamic acid, which was reduced to β-amino alcohol, was the starting compound. The hydroxyl group was protected by a dimethyl-tert-butylsilyl group. The benzyl ester in the side radical was cleaved by reduction on a palladium catalyst using ammonium formate. However, the subsequent acylation of cyclohexyl alcohol failed. In the second of the proposed schemes, a known sequence of reactions was used, which led to the formation of a cyclic derivative of Cbz-protected glutamic acid. Then, the resulting compound was acylated with cyclohexyl alcohol to give the desired ester. The subsequent transformation of the protective groups of the ester resulted in the diprotected L-glutamic acid in three stages. Subsequent reduction gave the desired protected β-amino alcohol containing a cyclohexyl protecting group in the side radical. This compound was further used in the Mitsunobu reaction to obtain a completely protected core of the PNA monomer. Subsequent thiolysis reaction resulted in the formation of the target secondary amine, the stability of which substantially exceeded the stability of its analog with benzyl protection, obtained and investigated before. The structure of the new compounds obtained is confirmed by 1H-NMR spectroscopy.

CHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALS

23-29 181
Abstract
It is interesting in chemical terms and promising in the applied production of new complexes of metals with bisphosphonic ligands with a popular set of consumer properties. To date, little has been studied chemistry of bisphosphonic acid complexes with the basic structure of 1-hydroxymethylene-bisphosphonic acid with a side chain containing 11 carbon atoms and ending with an amino group. The main objective is to obtain new bisphosphonates of s-, p -, d - and f-elements, their characterization by a complex of physical and chemical research methods (NMR and IR spectrometry, RSA, DTA, optical microscopy, laser diffraction) and to identify new applications of bisphosphonic acids and their salts. In the course of the work, complexes of Ag, Pb, Ca, with 1-hydroxymethylene-bisphosphonic acid (H2N(CH2)xC(OH)(H2PO3)2) and its derivatives, the side chain ends with an amino group, its length is 11 carbon atoms. Crystal structures of metal-bisphosphonate complexes with the general formula H2N(CH2)10C(OH)(HPO3)xM (M = Ag, Pb, Ca) were determined. The complexes were characterized by IR spectroscopy and 31P solid-state NMR spectroscopy, RSA. The areas of practical use of the complexes are outlined. It is shown, by the example of wastewater in Kuopio, Finland, that bisphosphonic acids can be used for wastewater treatment of enterprises from heavy metals (M =Pb, Zn, Cd, etc.).
30-37 293
Abstract
The results of elaborating a method for the synthesis of zirconia and hafnia doped by rare earths (yttrium, erbium and scandium) by using low-hydrated hydroxides of zirconium and hafnium as precursors are reported. The low-hydrated zirconium and hafnium hydroxides were prepared using the heterophase reaction. The physicochemical properties (including sorption properties) of low-hydrated zirconium and hafnium hydroxides ZrxHf1-x(OH)3÷1O0.5÷1.5·0.9÷2.9H2Owere studied. The scheme of thermal decomposition of low-hydrated hydroxides in air was determined. The sorption properties of the low-hydrated hafnium hydroxide are less pronounced owing to the lower amount of sorption centers, in this case, hydroxo and aqua groups. The sequence of stages of thermal decomposition of rare earth acetates was elucidated. Single-phase zirconia and hafnia doped by rare earths (yttrium, erbium and scandium) were obtained. The parameters of the elementary lattice were calculated for each phase. It was established that the stabilization of zirconium dioxide with yttria leads to the formation of interstitial solid solutions based on tetragonal zirconia (in the case of the composition Y2O3×4ZrO2 - cubic modification), with erbium oxide - interstitial solid solutions based on cubic zirconia; with scandium oxide - solid solutions based on tetragonal zirconia. The article presents the results of measuring electrical conductivity.

SYNTHESIS AND PROCESSING OF POLYMERS AND POLYMERIC COMPOSITES

38-48 243
Abstract
The mandatory requirement for creating high-quality asphalt concrete is the modification of the bituminous binder. Either polymers, typically SBS, or crushed vulcanizates are usually used as modifiers. Using the polymer modifier has a number of disadvantages: the poor compatibility of polymers with bitumen, the stratification of the modified binder during transportation and storage, the coalescence of the dispersed phase particles at the coating laying temperatures. The use of crushed vulcanizate as a modifier is limited due to the complexity of obtaining a particle with a micro-size and complex surface organization. By now a binary mixed powder "Polyepor-RP" based on rubber crumb and butadiene-styrene thermoplastic elastomer has been developed and obtained. It combines the advantages of both types of initial constituents and eliminates their shortcomings. The hybrid modifier is obtained by the method of high-temperature shear grinding. In addition, thanks to the use of modern rotary dispersants, the resulting hybrid modifier can be introduced into the asphalt mixture by uniformly loading it into the mixer at the closing stage of mixing, bypassing the long and energy-consuming stage of preparing the modified bituminous binder. The paper describes the comparative analysis of the rheological properties of four types of asphalt binders in accordance with the American testing system "SuperРave": unmodified bitumen of BND 60/90 grade; polymer-bitumen binder; bitumen modified with active rubber powder brand "Polyepor-A" and active binary powder brand "Polyepor-RP". It is established that the introduction of modifiers "Polyepor-A" and "Polyepor-RP" increases the resistance of asphalt pavement to the formation of ruts and increases the resistance to fatigue cracking. The introduction of the butadiene-styrene thermoplastic elastomer into bitumen has a positive effect only on the resistance to rutting. Using a hybrid modifier it is possible to obtain a rubberpolymer binder characterized by higher stability, resistant to delamination and phase separation, which will increase the durability of coatings
49-57 121
Abstract
New magnetic nanomaterials with magnetization up to 32 Gs·cm3/g were synthesized from highly branched ferrocene-containing polymers by thermal structural transformations in a field of 2.5 kOe. The structure and properties of the prepared polymers were studied by IR spectroscopy, transmission electron microscopy (TEM) and thermogravimetric analyses. According to IR spectroscopy the content of 1,3,5-substituted benzene rings in the ferrocene-containing polymer increases at 500°C. X-ray diffraction study showed that iron in such a sample is present exclusively in the form of Fe3O4 magnetite. As the heating temperature increased to 600°C, the composition of the samples became more complex: along with magnetite they contain cementite Fe3C and wustite FeO.97O. The magnetization of the ferrocene-containing polymer depends on the synthesis and heat treatment temperature. For a sample synthesized at 140°C the formation of a magnetically ordered phase begins at 500°C, and at 800°C the magnetization reaches a maximum value of 32 Gs·cm3/g. The average size of magnetic particles according to TEM analysis was 8-26 nm. The principal possibility of controlling the size and composition of the nanoparticles, as well as their magnetization depending on the conditions of production and the temperature of polymer structuring is shown. The obtained results provide a good basis for the directed synthesis of magnetic ferrocene-containing polymers with preset characteristics.
58-66 146
Abstract
The paper considers the properties of a number of commercially available Russian nitrilebutadiene rubbers (NBR) containing approximately the equal acrylonitrile amount (from 26 to 33%) in the macromolecule, but differing in the method of synthesis and isolation. The assessment ofthe influence of residual emulsifier content and also such surfactants as rosin and stearic acid introduced as technological additives on some NBR properties was performed. The technological properties of model compounds based on these NBR, in particular, Mooney viscosity, minimal and maximal torques during curing, and scorching time were determined. It was shown that both residual emulsifier amounts and introduced surfactants decrease the viscosity of the compounds and increase the curing time. It was noted that rosin acts in a different manner in comparison with stearic acid. In particular, stearic acid acting as an interstructural plasticizer affects viscosity decrease in a greater degree. The mechanical performance of vulcanizatesbased on rubber compounds considered in the paper was also determined. It was shown that the surfactants effect on the mechanical properties is negligible and is within the measurement accuracy. Nevertheless, the NBRs obtained with various emulsifiers differ essentially and can’t be replaceable without revising both the rubber compounds recipes and processing parameters. The vulcanizates resistance to some organic solvents and water was also studied. It was shown that the acrylonitrile content in the rubber macromolecule is the key factor affecting the resistance to non-polar solvents. At the same time it was found that the vulcanizates containing residual emulsifier amounts tend to the swelling index increase. In general, the surfactants effect on the swelling index is ambiguous, and it requires deeper research.
67-72 113
Abstract
The effect of non-polymeric components of a rubber mixture on the surface properties of butadienestyrene rubber obtained by solution polymerization was studied in the article. As non-polymeric components, ingredients widely used in the practice of the rubber industry were introduced into the rubber: fillers, surfactants of various types, and also sulfur - as a vulcanization agent. The surface free energy of the samples, a quantitative characteristic of the surface properties, was determined using the Owens-Wendt-Rabel-Kaelble method. It has been found that the surface properties of elastomeric compositions depend significantly on the solubility of the ingredients of the rubber composition and their adsorption properties. It has been shown that the most significant influence on the surface energy of butadiene-styrene rubber is exerted by the filler, on the surface of which rubber adsorption does not occur. The effect of surfactants on the surface energy of rubber compounds is different and depends on the nature of the surfactant. A partially soluble component - sulfur - in small quantities does not affect the surface energy of rubber samples. However, if it is present in the system in quantities greater than the solubility limit, it significantly reduces the surface free energy of the samples.

MATHEMATICAL METHODS AND INFORMATION SYSTEMS IN CHEMICAL TECHNOLOGY

73-81 157
Abstract
The article deals with the application of the system approach for constructing informationalgorithmic support for the pharmaceutical development of solid dosage forms. Information modeling of the life cycle of pharmaceutical drug development has been carried out starting from the stage of studying the active pharmaceutical substance and ending with the utilization of the drug. These models are built in the IDEF0 nomination. A generalized block diagram is presented that reflects, in its most general form, the iterative process of developing a ready-made dosage form as applied to the further transfer of technology. The basis of the system approach is QbD - "Quality planned in the development". To implement the QbD principle on the basis of the system approach, systemic set-theoretic models of information support of pharmaceutical development in the nomenclature of Melentiev have been constructed. A model for controlling the pressing process is also provided, which takes into account all the technological stages in the development of a solid dosage form. Functional models in the IDEF0 nomenclature of the technological process are constructed from the preparation of premises, personnel and components of the dosage form to the stage of packing and packaging of the finished dosage form. The construction of an informational intellectual control system for pharmaceutical development has been considered in detail with particular attention paid to the construction of a database of medicinal and auxiliary substances using the example of solid dosage forms. In Melentiev's bracket notation, the database of auxiliary substances necessary for the design of a solid dosage form is filled. The "Entity-relationship" model and the relational model for the database of medicinal and auxiliary substances have been constructe
82-83 48
Abstract
The solemn meeting to mark the 100th anniversary of the founding of the Second Moscow State University was held on October 16, 2018.


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