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Документ A research of chemical nature and surface properties of plant disperse fillers(PC Technology Center, 2020) Danchenko, Yu.; Kariev, A.; Andronov, V.; Cherkashina, A.; Lebedev, V.; Shkolnikova, T.; Burlutskyi, O.; Kosse, A.; Lutsenko, Yu.; Yavors'ka, D.Chemical nature and surface properties of plant disperse fillers are investigated: buckwheat (BH) and oat (OH) husk, wood (WF) and conifer flour (CF). Using IR spectroscopy, it was found that oxygen-containing atomic groups –OH, –C–O–, –C=O prevail in the filler components. It was found that a hydroxyl-hydrate layer of functional groups is present on the surface of air-dry fillers. By potentiometric titration of aqueous suspensions using the Parks–Bobyrenko method, it was determined that all fillers are of the "polyfunctional solid" type. It is shown that the hydroxyl-hydrate surface layer consists of functional groups with similar values of acid-base characteristics. Functional groups of acidic nature were additionally found on the surface of the fillers: groups with pKa≈4.37−5.66 on the BH surface, groups with pKa≈4.49−4.90 on the CF surface and groups with pKa≈3.91−4.30 on the WF surface. As a result of potentiometric titration, it was shown that the surface acidity of the fillers decreases in the WF>CF>BH>ОH series, which coincides with the one in which the total cellulose and lignin content decreases, and the resistance of fillers to thermal-oxidative breakdown increases. It was found that the rate of hydrolytic processes in aqueous suspensions at the interface decreases in the ОH>CF>BH>WF series and inversely depends on the concentration of functional groups on the surface of the fillers, and also that the change in the rate of hydrolytic processes at the interface depending on the content of fillers is described by step functions. It is revealed that for the effective use of the studied disperse waste in composite materials and as adsorbents for the extraction of pollutants, dispersion media with the following ranges of the hydrogen index are required: for BH − pH>4.4; OH − pH>6.4; WF − pH>3.9; CF − pH>4.5. The results obtained make it possible to predict and control acid-base interfacial interactions, as well as reasonably approach the development of new effective technologies.Документ Sorption studying of environmentally friendly polymeric materials(Національний університет цивільного захисту України, 2021) Lebedev, V. V.; Tykhomyrova, T. S.; Lozovytskyi, A.; Grigorova, T.; Filenko, O.; Cherkashina, A.Документ Investigation of the destruction of furano-epoxy composites within the framework of fractal geometry(ТОВ "ТО Ексклюзив", 2018) Rassokha, A.; Cherkashina, A.; Sukhostavskaya, M.Документ Designing low viscosity furan epoxy polymers of the materials for construction industry(Технологический центр, 2016) Rassokha, A.; Cherkashina, A.The materials are designed and the properties are studied of the low viscosity furanepoxy reactive oligomers, structured by amine complex curing agents for the use as injection systems during the repairing and recovery construction work. A wide range of the amine containing structuring agents that have industrial potential and ensure a high degree of conversion was analyzed. This makes it possible to form the rational structure of furan epoxy polymers, which is due to the application of optimal parameters of structuring (temperature, concentration of ingredients, time and others) during the formation of the polymeric composition systems for construction purposes. The structure topological parameters were studied (traditional topological criterion of Wiener and others) and certain parameters of reactivity (structural functionality, formal unlimitedness, the index of distribution of electron density on the atoms of molecule, etc.) parent substances (monomers) during obtaining furan epoxy materials. The knowledge of this set of characteristics makes it possible to purposefully regulate structure and properties of the designed low viscosity injection furanepoxy polymeric materials. The deformation strength, adhesive, sorption, technological properties of the proposed low viscosity injection furan epoxy polymers for construction purposes were explored. As a result of the optimal combination of the set of structural topological parameters and technological factors, the high level of physical mechanical, adhesive properties, water resistance of the designed composite materials is ensured. The development of composite polymeric systems was accomplished with the use of the “green chemistry” principles.