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2022

Archives Journal Chemical Bulletin Vol. 5

STUDYING THE POSSIBILITY OF USE OF BETULIN AS AN ANTIOXIDANT OF NITRILE BUTADIENE RUBBER

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 5-14 p.
Abstract
Comparative tests of phenolic compounds of various structures (2,6-ditert-butyl-phenol (ionol) and betulin (betulinol, lup-20(29)-en-3, 28-diol), which belongs to pentacyclic triterpene alcohols of the lupane series in as antioxidants of emulsion nitrile rubber.The outer layer of birch bark (bark) contains up to 35-40% of pentacyclic triterpenoids, among which betulin predominates.It has been shown that the use of betulin will not only reduce unproductive losses of antioxidants in the process of synthesis of butadiene-nitrile rubbers, but and will reduce the negative burden on the environment by reducing the concentration of phenols in industrial effluents sent to treatment facilities.It has been established that in the process of thermal-oxidative aging, betulin, in comparison with ionol, provides more effective protection for vulcanizates based on butadiene-nitrile rubber. solubility preservation of nitrile rubber containing its ionol and betulin, as well as the nature of the change in the rheological properties of rubber and the elastic-strength properties of compositions based on it, showed the possibility of using betulin as an antioxidant for carbochain polymers.
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STRUCTURE OF IONITE SYNTHESIZED ON THE BASIS OF PHENOL-FORMALDEHYDE RESIN AND DERMAL COLLAGEN HYDROLYSATE

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 15-27 p.
Abstract
An ion-exchange weakly acid phenol-formaldehyde resin capable of adsorbing heavy metals has been synthesized. A new material, dermal collagen hydrolysate, was used as a resin modifier to impart ion–exchange properties. IR and EPR spectroscopy methods have established that the active centers of the sorbent obtained are carboxyl and amino groups. It is assumed that the presence of amino groups increases the sorption capacity under normal temperature conditions. By EPR spectroscopy, it was found that the adsorbed heavy metal ion becomes in an axial position.
Using an electron microscope, it was found that a decrease in the liquid coefficient (LC) of the hydrolysate leads to an increase in the porosity of the ionite (up to LC8), resulting in an increase in the sorption capacity, with a further decrease in the liquid coefficient, it is likely that the number of hydrolyzed protein molecules is sewn into the resin structure with a frequency sufficient to prevent pore formation. According to studies of the ionite surface, the synthesized ionite can be attributed to macroporous cationites – the ionite pore size reaches 37.3 microns.
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SPECTRAL CHARACTERISTICS OF TRYPTOPHAN AND PHENYLALANINE COMPLEXES WITH MAGNESIUM (II) AND ZINC (II)

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 28-38 p.
Abstract
One of the main tasks of modern science is the search and synthesis of compounds with desired useful properties. Close attention should be paid to the study of mixed-ligand metal complexes containing metal ions and various ligands, which are biologically active molecules. In this work, the synthesis of complexes of phenylalanine and tryptophan with magnesium (II) and zinc (II) was carried out, some physical properties of the obtained substances were studied. The IR and UV spectra of the synthesized substances were obtained. In the IR spectra of the complexes, a shift and disappearance of some characteristic frequencies are observed. The disappearance of fluo-rescence, which is characteristic of individual amino acids, is observed in the UV spectra. An assumption has been put forward about the participation of metal in this effect. The physical properties of the synthesized substances have been studied, in particular, the melting points and the solubility of the complexes in water have been analyzed. There is a decrease in melting points compared to the starting materials, as well as a drop in solubility. Thus, the obtained results indicate the success of the synthesis of Mg(II) and Zn(II) metal complexes with phenylalanine and tryptophan. The practical significance of the synthesized substances lies in the use of metal complexes in medicine, agriculture and other branches of science and technology, as bioadditives, medicines or for physical research.
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EXCESS HEAT CAPACITIES OF THREE-COMPONENT SYSTEMS AND THEIR ROLE IN THE CALCULATION OF THE HEAT BALANCE OF DISTILLATION

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 39-58 p.
Abstract
The work is devoted to the research of the influence of real values of the heat capacity of ternary mixtures on the energy consumption of the process in a distillation column. The results of the analysis of available reference experimental data for six ternary systems and their binary components are presented in the form of isoline diagrams of excess heat capacities. Additive and excess heat capacities of ternary mixtures, vapor-liquid equilibrium and different regimes, including those of extractive distillation, are calculated. It is shown that the dependences of the excess heat capacity on the composition of ternary mixtures are complex, and the use of real values makes it possible to estimate energy costs more correctly.
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PARTICLE SIZE DISTRIBUTIONS OF SUSPENSIONS PRODUCED BY USING BEAD MILLS

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 59-70 p.
Abstract
The results of the experimental studies of dispersion process of solid material in liquid medium using bead milling were presented in this article. The method of the experiment conducting was described. Differential and integral functions of distribution of solid phase particles in the suspensions were used. As a result of the research, the influence of the main technological parameters on the particle size distributions of the obtained suspensions and the specific surface of solid phase was established. The main considered parameters were: the duration of grinding, the consumption of the suspension, the speed of the mill rotor and the addition of a surfactant to the initial suspension. It was established, that the main process occurring in a bead mill is the crushing of large fractions of solid material in the initial suspensions. The process of the multiple grinding was also investigated.
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FEATURES OF THE COMPOSITION AND STRUCTURAL AND MORPHOLOGICAL CHARACTERISTICS OF THE ACTIVATED HYDROALUMOSILICATE OF THE POLYANSKOYE DEPOSIT

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 5-15 p.
Abstract
The results of a comparative study of the features of the material (chemical and mineralogical) composition and some surface characteristics of the enriched form of clay from the Polyana deposit subjected to activation by sulfuric acid treatment, as well as by exposure to IR- and UV-radiation are presented in this article. The initial clay material is accessible to polymineral rock with a predominance of montmorillonite hydroaluminosilicate in its composition (up to 75 wt %). There is IR and UV exposure to a significant change in the incoming composition of the clay, not observed. When an enriched form of clay is exposed to a solution of sulfuric acid, the proportion of cations (in particular calcium) in the exchange complex of clay decreases. In this case, a compensatory effect of protons on broken bonds localized on the surface of clay minerals is observed, which leads to a decrease in the absolute value of the electrokinetic potential on the surface of clay particles. Under IR- and UV-exposure of the clay material, a shift in the ξ-potential to the region of negative values is observed, which can be explained by the weakening of the bonds of exchange cations with the crystal lattice of montmorillonite, and, as a result, a change in the composition and structure of the interlayer medium. It was revealed that both UV and IR exposure to Polyanskaya clay leads to a decrease in the content of the proportion of freely bound water in the structure of montmorillonite hydroaluminosilicate. At the same time, treatment with UV-radiation significantly reduces the amount of OH-groups on the surface of the mineral due to the formation of siloxane bridges.
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ELASTOMERIC COMPOSITIONS BASED ON BUTADIENE-NITRILE RUBBERS WITH THE ADDITION OF A NEW OLIGOESTERAMIDE

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 16-25 p.
Abstract
The effect of air oxygen and several catalysts on the process of aminolytic destruction of polyethylene terephthalate by a mixture of amino alcohols (monoethanolamine and triethanolamine) at atmospheric pressure and convective heating is investigated. The terephthalic acid diamide obtained as a result of PET degradation is used as a monomer in the homofunctional polycondensation reaction. A new oligoesteramide containing an aromatic ring, two amide and hydroxyl groups in its structure was obtained. Its molecular weight was determined by a viscometric method. The use of the obtained oligoesteramide as a plasticizer in polar elastomeric compositions based on a mixture of butadiene-nitrile rubbers BNKS-40 and BNKS-28 is proposed. The effect on the kinetics of sulfur vulcanization and the viscosity of raw rubber mixtures is demonstrated. The acceleration of the vulcanization process has been revealed, as well as a decrease in the viscosity of rubber compounds, which contributes to a reduction in energy costs for processing and molding products. The change of elastic-strength parameters of vul-canized rubbers is substantiated. Comparison of rubber mixtures with oligoesteramide and plasticizers dibutyl phthalate, dioctyl phatalate and dibutylsebacinate was carried out. With the introduction of terephthalic acid oli-goesteramide, the elongation at break increases by 50-70 percent. The use of the obtained oligoesteramide as a plasticizer has an advantage relative to the selected comparison plasticizers, namely, the absence of "sweating" on the surface of the products during storage due to the higher molecular weight of oligoesteramide.
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ANALYSIS OF TRIPLE RECIPROCAL SYSTEMS BASED ON S1-ELEMENT NITRATES AND HALOGENIDES

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 26-38 p.
Abstract
Currently, the relevance of using more advanced and universal chemicals in the creation of electrolytes of heat carriers of non-melting salt mixtures and thermal batteries is increasing. Based on this, it can be stated with confidence that the halide and nitrate salts of s1-elements have the greatest potential in this direction. When developing the latest generators of electrical and thermal energy, such chemicals have a unique property - the abil-ity to run power plants even at low temperatures. For a wide practical application of melts of halides and nitrates of s1 elements with specified values of thermodynamic characteristics and physico-chemical properties, the study of phase diagrams is required. The method of differential thermal analysis was used to study the phase equilibrium of salt systems of the following type: Li,Rb||I, NO3, Li,K||Br,NO3, Li,K||I,NO3, Li, K||F,NO3, Li, K||Cl,NO3, Li,Rb||Br,NO3, Li,K||Br,NO3, Li,Na||I,NO3, Li,Rb||F,NO3. A comparative analysis of the series of three-component mutual systems formed from the systems experimentally studied by the authors of the article Li,K||F,NO3, Li,K||Cl,NO3, Li,K||Br,NO3, Li, K||I,NO3, Li,Na||F,NO3, Li,Na||I,NO3, Li,Rb||F,NO3, Li,Rb||Br,NO3, Li,Rb||I,NO3,Li,Cs||F,NO3, Li,Cs||Cl,NO3, Li,Cs||I, NO3 and systems studied by other authors Li,Na||Cl,NO3, Li,Na||Br, NO3, Li,Rb||Cl,NO3, Li,Cs||Br,NO3. The considered eutectic compositions of salt systems can be used to create a molten source of RHIT.
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EVALUATION OF EMULSIFIER EFFECT ON THE PROPERTIES OF WATER-BASED ALKYD EMULSION

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 39-48 p.
Abstract
The study is devoted to the issue of evaluating the effect of an emulsifier on the properties of the developed water-based alkyd emulsion intended for dust suppression. The goal was to establish a rational ratio of components in this system according to the following criteria: a decrease in the average droplet size, a decrease in relative viscosity, and an increase in sedimentation stability (emulsion life). The components of the basic composition of the emulsion were alkyd varnish (Resin GF-0123), surfactant (AMP-95), distilled water. To analyze the obtained compositions of the alkyd emulsion, dispersions were prepared containing: alkyd – 55-75% with a step of 5%; Surfactant – 0.1-0.5% in increments of 0.1% of the alkyd content (in-stead). The emulsion was obtained under the following technological parameters: emulsification temperature – 35°C, emulsification speed – 5000 rpm. The analyzed parameters were: dispersion (droplet size), viscosity, life (sedimentation stability) of the emulsion. It has been established that a rational composition, at which the minimum values of dispersion and viscosity are achieved, with a high lifetime at the maximum content of the polymer component, is a composition that includes: 59.7% alkyd, 40% water and 0.3% surfactant. The developed composition makes it possible to obtain an emulsion with a lifetime of more than 1 month, an av-erage dispersion value of 3 µm, and a viscosity of 40 mPa·s.
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SYNTHESIS OF GRAFT COPOLYMERS BASED ON SKF-32 BY ATOM TRANSFER RADICAL POLYMERIZATION

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 7-18 p.
Abstract
The use of partially fluorinated polymer electrolyte membranes in fuel cells is a very promising approach. Due to this, it is possible to avoid the disadvantages that arise when using perfluorinated polymers containing sulfonate groups as proton exchange membranes. Such disadvantages include high cost, unsatisfactory characteristics of proton transport with low water content and high values of hydrogen permeability through the membrane. Materials based on vinylidene fluoride are representative partially fluorinated polymers that exhibit interesting thermal, chemical, physical and technological properties. One of the promising directions for creating proton-exchange membranes is creation of graft fluoropolymers containing sulfonate groups. Samples of grafted copolymers based on industrial fluoroelastomer SKF-32 (a copolymer of vinylidene fluoride and chlorotrifluoro-ethylene) was carried out by grafting styrene with subsequent sulfonation. Graft poly(vinylidene fluoride-co-chlorotrifluoroethylene-g-styrene) was synthesized by atom transfer radical polymerization (ATRP). The data of viscometry and FT-IR spectroscopy allow us to conclude about the successful grafting of polystyrene fragments. Sulfonation of the grafted copolymer was carried out by injecting an acetyl sulfate solution to a polymer solution in 1,2-dichloroethane at a temperature of 40°C for 3 hours in an argon atmosphere. The qualitative composition, characteristic viscosity, molecular weight distribution and concentration of sulfogroups in the studied samples were investigated. The concentration of cross-linked polymer chains increases with an increase in the duration of synthesis, which complicates the sulfonation process. Optimal synthesis conditions were determined: temperature 90оC, initiator ‒ 2,2’-bipyridyl, duration – 3-4 h. Under these conditions, the highest yield of the finished product is achieved and unintentional crosslinking of the polymer does not occur.
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