Факультет митної справи, матеріалів, технологій та гостинності

Постійне посилання на фондhttps://repository.lntu.edu.ua/handle/123456789/47

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Preparation of Sintered Light Termoperlites for Application in Construction
(Madrid: ACEX, 2024) Sadova, Oksana; Melnychuk, Mykola
The 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.
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, Vitalii
The 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.
Influence of Additives Processed by Physical Fields on Tribotechnical Properties of Polymer Composites
(2022) Sadova, Oksana; Kashytskyi, Vitalii; Melnychuk, Mykola
The influence of specific load on the intensity of weight and linear wear is determined in the article. The coefficient of friction and temperature in the zone of tribocontact of polymer composites, the components of which were processed in physical fields, were studied. The study of polymer composites with different content of components carried out at a constant sliding speed of 0.5 m/s. Epoxy resin and polyethylene polyamine hardener were used as a matrix to form polymer composites. To ensure increased heat resistance of the polymer matrix, a modifying additive (organosilicon varnish) was used. For the first time, the processing of organosilicon varnish in an electromagnetic field was applied, which allowed removing part of the solvent. Discrete aramid and glass fibers were used as reinforcing additives. For the first time, ultrasonic treatment of fibers in acetone was used, which allowed cleaning the surface of the fibers from contaminants and lubrications. Because of the use of the modifying additive and treated discrete fibers, the wear resistance of polymer composites increased by 30% due to the improvement of the adhesive interaction between the components of the system and the reduction of structural defects of the material. Removal of lubrication from the surface of the fibers and the solvent from the modifying additive increased by 0.1–0.15 the coefficient of friction of the polymer composites and will improve their service life. Friction polymer composite materials with high density and improved tribotechnical properties are designed for manufacturing brake systems of scooters.
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, Valentyna
This 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.
Properties and formation technology of glutinous biocomposite materials
(Boston: Primedia eLaunch, 2023) Sadova, Oksana; Kashytskyi, Vitalii
The monograph presents the general characteristics and classification of biocomposite materials based on natural components, their advantages and scope of application are indicated. The mechanical properties of biocomposite materials based on a glutinous matrix and plant fillers were studied. The content of components was optimized. The formation modes of biocomposites with processing of the composition in physical fields were determined. The technology of recycling glutinous biocomposite products by thermo-mechanical processing of secondary raw materials has been developed. The monograph is intended for specialists in materials science of polymer composites and biocomposite materials. It will also be useful for graduate students, students, materials scientists, technologists and engineers of technical specialties.
The development of glutin-based biocomposite materials with advanced hydrophobicity
(Lutsk: LNTU, 2024) Kashytskyi, Vitalii; Sadova, Oksana; Shehynskyi, Oleh
Biocomposite 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 environment
Optimization of the mode of thermal treatment of biocomposites filled with coffee grounds
(Lutsk: LNTU, 2024) Sadova, Oksana; Kashytskyi, Vitalii
Study of mechanical properties and structure of biomposits filled with chopped stalks of cereals crops
(Луцьк: ЛНТУ, 2024) Sadova, Oksana
В статті досліджено міцність на стискання біокомпозитних матеріалів на основі глютинової матриці, яку готували за різного співвідношення компонентів. Як напонювач для біокомпозитних матеріалів використано подрібнені стебла зернових культур. Досліджено міцність на стискання біокомпозитів залежно від ступеня підсушування композиції. Проведення додаткової термічної обробки забезпечило підвищення механічних характеристик біококомпозитів. Ударну в’язкість матеріалу визначено залежно від вмісту наповнювача, ступеня підсушування та тиску пресування композиції, а також проведення додаткової термічної обробки біокомпозитів. Структуру біокомпозитів досліджено методом ІЧ-спектроскопії на основі аналізу функціональних груп.
Study of mechanical properties and structure of biomposits filled with coffee grounds
(Луцьк: ЛНТУ, 2025) Sadova, Oksana; Kashytskyi, Vitalii; Husachuk, Dmytro
В 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%.
Designing tribotechnical epoxy composite materials reinforced with chopped fibers and modified with silicon organic varnish
(Kharkiv: Technological center, 2024) Sadova, Oksana; Kashytskyi, Vitalii; Tkachuk, Valentyna; Shehynskyi, Oleh; Parfentyeva, Inna
The object of research is modified epoxy composite materials containing fibrous fillers treated in physical fields. The technological features of the development of tribotechnical epoxy composites, which must withstand the effects of elevated temperatures, have been considered. In this case, it is necessary to modify the structure of the epoxy polymer matrix, which is achieved as a result of the introduction of heat-resistant organosilicon varnish. Organosilicon varnishes and chopped fibers contain technological additives, which complicates the process of structuring epoxy composites and leads to the appearance of structural defects. Removal of technological additives and cleaning the surface of the aramid and glass fibers from lubricants is possible as a result of processing the components of the composition in physical fields. There is a need to study the influence of physical fields on the structuring processes of the epoxy system and the formation of the structure of epoxy composites with specified properties. Modified epoxy composites contain chopped aramid and glass fibers treated with ultrasound. The tribotechnical characteristics of epoxy composites were studied at a sliding speed of V=1.0 m/s with a change in specific load from 0.5 MPa to 1.5 MPa. The temperature in the tribocontact zone during frictional interaction rises to 100 °C with an increase in the specific load. An increase in the density of the surface layer of tribocontact of epoxy composites with fillers treated in physical fields was revealed. The practical recommendations have been compiled for the implementation of the treatment technology of components in physical fields, which ensures structuring of epoxy composites with high tribotechnical characteristics

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