Факультет митної справи, матеріалів, технологій та гостинності
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Item type:Матеріали конференцій, Preparation of Sintered Light Termoperlites for Application in Construction(Madrid: ACEX, 2024) Sadova, Oksana; Melnychuk, MykolaThe obtained strength values make it possible to use this material in construction since the widely used ceramic brick of the M150 brand has a compressive strength of 15 MPa. Compared to other alternative materials the strength of the geopolymer filled with perlite was only 2.3 MPa, and that filled with vermiculite was 3.75 MPa. That is, the obtained strength values are higher than the average values obtained by other authors [3,5,7]. Mechanical properties correlate with the porosity of the material and its density.Item type:Наукова стаття, Intensification of the formation process of sodium sulfate-modified biocomposite materials based on the glutinous matrix(Kharkiv: Institute of Single Crystals of the National Academy of Sciences of Ukraine, 2023) Sadova, Oksana; Kashytskyi, VitaliiThe influence of the modifying additive (sodium sulfate) on the heat treatment regime of the biocomposition in the mold investigated in the article. The optimal content of sodium sulfate in the biocomposite material was determined. The influence of the content of the modifying additive on the compressive strength of biocomposites structured at different temperatures has studied. The optimal parameters of the thermal field temperature and the duration of heat treatment of the biocomposition for the given content of the additive, which provides the maximum values of mechanical characteristics, are determined. It established that the modifying additive with optimal content is able to increase the intensity of structuring of biopolymer binder. This consists in the rapid transition of the glutin binder from the gel state to the solid state with the formation of physicochemical bonds due to the removal of excess moisture under the influence of temperature. Fractograms of the fracture surface of biocomposites containing sodium sulfate analyzed.Item type:Наукова стаття, Design of biocomposites based on a glutinous matrix with a combined content of wood flour and chopped stalks of grain crops(Kharkiv: TECHNOLOGY CENTER, 2026) Sadova, Oksana; Kashytskyi, Vitalii; Tkachuk, ValentynaThis study considers biocomposite materials based on a glutinous matrix and fillers of plant origin. Waste from the woodworking industry and the agricultural sector is a promising raw material for obtaining fillers for biocomposite materials, which are characterized by a high degree of environmental safety and renewable raw material base. The task addressed is to optimize the amount of technological additive (water) in the glutinous composition, which contributes to the formation of a dense structure of the biocomposite material with a compact arrangement of particles of the combined mixture of fillers. In the process of research, the effectiveness of using fillers of different granulometric composition against the effect of mechanical loads was determined. The complex effect of fillers of plant origin on the mechanical characteristics of biocomposite materials was studied, which made it possible to define the optimal composition of the biocomposite. An analysis of the effect of the amount of moisture in the composition on the formation of the structure and the resistance of the biocomposite material to the effect of static and dynamic loads was carried out. The maximum values of the ultimate compressive strength (115–120 MPa) were obtained for biocomposites containing a mixture of fillers of different granulometric composition (40–80% of cereal stalk particles, the remaining particles of wood flour) provided that 30% of moisture is removed from the composition. The maximum impact strength (13.8 kJ/m2) was established for biocomposites containing 100% of crushed cereal stalks provided that 10% of moisture is removed from the composition. The designed materials could be used to manufacture packaging elements that are disposed of after operation by recycling or through safe decomposition at landfills without harm to the environment.Item type:Наукова стаття, The development of glutin-based biocomposite materials with advanced hydrophobicity(Lutsk: LNTU, 2024) Kashytskyi, Vitalii; Sadova, Oksana; Shehynskyi, OlehBiocomposite materials, which contain components of natural origin, have low resistance to water absorbtion due to high lyophilicity of components. It leads to quick destruction of biocomposite products under the conditions of high humidity exploitation that defines the necessity and importance of conducting scientific research in this sphere. The aim of the article is to research the hydrophobic additives influence on the compressive strength and hygroscopicity of biocomposite materials consisting of glutin matrix (100 parts by weight) and wood flour (100 parts by weight). The technology of forming biocomposite materials includes a step-by-step pressing the composition at a pressure of 10-15 MPa and a heat treatment of the product in a press mold at a temperature of 140°C. Experimental methods of investigating the biocomposite materials compressive strength and hygroscopicity were used in the work. It was experimentally determined that the modifying additive (paraffin) optimal content is 4 parts by weight per 100 parts by weight of biopolymer matrix. At this content, there is an increase compressive strength by 2.8-4.6 times of the biocomposite materials compared to biocomposites with different paraffin content. As a result of the state analysis of biocomposite samples which were destroyed under the static loading influence, the features of the cracks occurrence and propagation in biocomposites depending on different modifying additive content, the conduct of the composition preliminary processing or biocomposites additional processing in a thermal field were determined. The use of protective hydrophobic coatings on the biocomposite samples surface provided an increase in the biocomposites resistance to the moisture negative influence. The most effective were coatings based on a paraffin solution, which provided a reduction in water absorption by 45-50% compared to biocomposites coated with wax, drying oil Oksol, and sunflower oil. The complex use of hydrophobic substances as modifying additives and protective coatings has practical significance, as they positively affect the processes of forming the structure, increasing the strength and hydrophobicity of biocomposite materials used in a humid environmentItem type:Наукова стаття, Оптимізація технології отримання біокомпозитів, наповнених подрібненими стеблами зернових культур(Луцьк: ЛНТУ, 2022) Садова, Оксана ЛеонідівнаPurpose. To optimize the temperature-time modes of heat treatment of highly filled biocomposites based on glutin and chopped stalks of grain crops, formed by the method of hot pressing of the composition. Method. A glutinous solution used as a matrix for the formation biocomposites with a high degree of filling. As a filler used chopped stalks of grain crops in fractions of 0.5 and 0.7, pre-dried for 1 hour at a temperature of 50-60 °C. Biocomposite samples formed by the method of hot pressing of the composition. The compressive strength limit determined by compressing cylindrical samples with a diameter of 20 mm and a height of 40-45 mm using a static load at a speed of movement of the lower traverse of the press of 2 mm/min. Results. The topical direction of modern materials science in the area of composite materials is the development of eco-friendly biocomposites, since the polymer matrix is biodegradable and renewable sources. This direction is new, therefore, it requires the development of the composition and production technology of biocomposites, as well as the study of their properties. In the article, various forming technologies and heat treatment regimes developed in order to increase the strength of highly filled biocomposite materials based on glutin and crushed stalks of grain crops. Scientific novelty. It discovered for the first time that at the last stages of structuring biococomposites, it is necessary to lower the temperature of heat treatment (drying) and increase its duration, which will ensure the avoidance of structural defects (cracks) in the material. The technology of obtaining biocomposite products has been optimized due to the drying of biocomposite materials after the main and additional heat treatment. This complicated the technology of obtaining products from biocomposites, but made it possible to remove excess moisture from the materials. Moisture gets into the material from the glutin solution, which is prepared by pouring bone glue with water, that is necessary for the formation of the composition. Long-term drying of biocomposites at low temperatures ensures uniform gradual removal of moisture from the material without the formation of cracks. The compressive strength of biocomposites produced using this technology is 53.3 MPa. Practical significance. The developed biocomposite materials are biodegradable and environmentally friendly. Therefore, it is advisable to use them for the production of disposable containers, which will solve the problem of waste disposal and improve the ecological safety of the environment.Item type:Наукова стаття, Study of mechanical properties and structure of biomposits filled with coffee grounds(Луцьк: ЛНТУ, 2025) Sadova, Oksana; Kashytskyi, Vitalii; Husachuk, DmytroВ статті досліджено міцність на стискання біокомпозитних матеріалів на основі глютинової матриці та кавової гущі залежно від вмісту наповнювача та ступеня підсушування композиції. Визначено міцність на стискання біокомпозитів залежно від концентрації біополімерної матриці, вмісту композиції в прес-формі, температури основної термічної обробки та додаткової термічної обробки. Досліджено, що максимальну міцність на стискання 79,6 МПа мають біокомпозитні матеріали із ступенем підсушування 20%. Також досліджено мікроструктуру біокомпозитів оптимального складу (вміст кавової гущі в кількості 200 мас. ч.) зі ступенем підсушування композиції 20%.Item type:Наукова стаття, Development of glutinous biocomposite materials filled with coffee grounds(Lutsk: LNTU, 2024) Sadova, Oksana; Kashytskyi, Vitalii; Shehynskyi, OlehThe intensive development of biocomposite materials is associated with the use of waste from agricultural production or the food industry as raw materials. Such raw materials are renewability and eco-friendly, but require special processing for preparation for use as a filler and development of methods of forming biocomposite products, which determines the high relevance of research in this direction. The aim of the work was to study the intensity of the influence of the mechanical and thermal fields on the mechanical properties and nature of the structuring of glutinous biocomposite materials with a high content of coffee grounds (190-200 wt. parts). The forming technology of biocomposite materials consisted in heat treatment of the composition. Next stages are pressing and holding of composition at a temperature of 150°C under a pressure of 8-11 MPa. The work used the methods of determining a compressive strength and an impact toughness. The method of infrared spectroscopy was also used to study structuring processes. It was established that the use of coffee grounds in the quantity of 200 wt. parts provides an increase in compressive strength up to 75.8 MPa under the condition of forming a biocomposite material with a density of 1.17 g/сm3. An increase in the resistance of biocomposites to dynamic loads occurs in the case of the introduction of a filler in the amount of 190 wt. parts using a preliminary pressing at a specific load of 8 MPa. The practical significance of this work lies in developing an optimal thermo-mechanical processing mode, involving maximum exposure of the composition in a press mould within a thermal field for 2 hours, which enhances the mechanical properties of glutinous biocomposite materials.