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Vol. 5 Issue 4

Archives Journal Chemical Bulletin Vol. 5 Issue 4

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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