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Composites Based on PLA/PHBV Blends with Nanocrystalline Cellulose NCC: Mechanical and Thermal Investigation
(2024-12-10) Bazan, Patrycja; Rochman, Arif; Mroczka, Krzysztof; Badura, Kamil; Melnychuk, Mykola; Nosal, Przemysław; Węglowska, Aleksandra
This study investigates the physical and mechanical properties of biodegradable composites based on PLA/PHBV blends modified with different content of nanocrystalline cellulose (NCC) of 5, 10, and 15 wt.%. Density measurements reveal that the density of the composite increases with increasing NCC content. Water absorption tests demonstrate a gradual increase in the composite water content with increasing incubation time, reaching stabilization after approximately 30 days. Mechanical testing was also carried out on both on conditioned samples after the process of hydrolytic degradation and accelerated thermal aging. The conditioned composites show an increase in the stiffness of the materials with increasing content of nanocrystalline cellulose. The ability to deform and the ability to absorb energy when the sample is dynamically loaded decrease. The repeated strength tests, after the process of incubation of samples in water and after the process of accelerated thermal aging, show the degradation of composite materials; however, it is noticed that the introduction of cellulose addition reduces the impact of the applied artificial environment in aging tests. The findings of this study indicate promising applications for these types of materials, characterized by high strength and biodegradability under appropriate conditions. Household items such as various containers or reusable packaging represent potential applications of these composites.
Vibration Welding of PLA/PHBV Blend Composites with Nanocrystalline Cellulose
(2024-12-15) Bazan, Patrycja; Kozub, Barbara; Rochman, Arif; Melnychuk, Mykola; Majewska, Paulina; Mroczka, Krzysztof
Thermoplastic composites have garnered significant attention in various industries due to their exceptional properties, such as recyclability and ease of molding. In particular, biocomposites, which combine biopolymers with natural fibers, represent a promising alternative to petroleum-based materials, offering biodegradability and reduced environmental impact. However, there is limited knowledge regarding the efficacy of joining PLA/PHBV-based biocomposites modified with nanocrystalline cellulose (NCC) using vibration welding, which restricts their potential applications. This study demonstrates that vibration welding enables efficient bonding of PLA/PHBV composites with NCC, resulting in strong, biodegradable, and environmentally friendly materials. The investigation revealed that the addition of nanocrystalline cellulose (NCC) at 5, 10, and 15 wt.% significantly enhanced the strength of welded joints, with the highest strength achieved at 15% NCC content. Microstructural analysis using scanning electron microscopy (SEM) and deformation studies with digital image correlation (DIC) indicated that a higher NCC content led to greater local deformation, reducing the risk of brittle fracture. Mechanical hysteresis tests confirmed the composites’ favorable resistance to variable loads, highlighting their stability and energy dissipation capabilities. Optimization of welding parameters, such as vibration amplitude, welding time, and pressure, is crucial for achieving optimal mechanical performance. These findings suggest that PLA/PHBV composites modified with NCC can be utilized as durable and eco-friendly materials in various industries, including automotive and packaging. This research presents new opportunities for the development of biodegradable high-strength materials that can serve as alternatives to traditional plastics.
Properties of Perlite-Based Geopolymer as a Thermal Insulation Material for Building Efficiency
(2025) Polivoda, Nina; Melnychuk, Mykola; Kozub, Barbara; Ostapchuk, Roman; Babych, Yaroslaw
Globally, the key issues related to technology and materials are the reasonable consumption of exhaustible resources, increasing technological efficiency, reducing waste, and sustainable production. The construction industry is responsible for huge carbon dioxide emissions and other harmful waste in this context. Moreover, it requires about 16 percent of the world’s annual energy use for the production of cement-based products. Experts estimate that without effective changes, the negative impact on the environment and consumption will increase to 25% by 2050. This paper presents a geopolymer based on expanded perlite up to 85% that can be used as a modern lightweight thermal-insulation construction material. The results showed that the density of the samples varied from 330 kg/m3 to 510 kg/m3, the bending strength was from 1 MPa to 2 MPa, the compressive strength was from 13.5 MPa to 21 MPa, the thermal conductivity was from 0.09 W/m K to 0.130 W/m K, the water absorption coefficient was from 77% to 137%, and the total porosity of the material was from 60% to 65%. The results meet the requirements for lightweight building materials for wall construction regarding the leading indicators. Still, high water absorption significantly decreases strength and thermal conductivity after 100 h of the aging process. To reduce the water absorption of the perlite-based geopolymer, research is planned to apply a hydrophobic coating based on metakaolin.
Thermo-Mechanical Properties of Perlite Composite
(2021) Melnychuk, Mykola; Poteichuk, Mykhailo; Kashytskyi, Vitalii; Sosnowski, Marcin; Kutsyk, Serhii
Currently, perlite is used in the insulation of facades, roofs, ceilings, based on perlite, heat-insulating plasters, masonry mortars, and even adhesive compositions are produced. However, practically not used as a monolithic-structural material. Expanding the production of heat-insulating perlite materials for various purposes will inevitably be allowed to reduce heat loss and the high cost of fuel. Perlite materials can improve the physical properties of existing structures. A significant advantage of the use of perlite as a heater is a reduction in a fire hazard and an increase in the fire resistance of building structures. The article presents the results of a study of the monolithic heat-insulating material based on expanded perlite of deposit “Fogosh” (Zakarpatskyi region, Ukraine) and liquid silicate sodium glass. The basic thermal, mechanical properties, and structures of this material and compliance with the standard are investigated. In this article, describe a complex of properties of new thermal insulation material that has: ρ = 219 kg/m³, λ = 0.087 W/(m K), σc = 9.1 MPa. It is established that the investigated perlite composite according to its strength and thermal conductivity characteristics can be recommended as thermal insulation and structural material for thermal power equipment isolation.
The Influence of the Addition of Basalt Powder on the Properties of Foamed Geopolymers
(MDPI AG, 2024-05-14) Łach, Michał; Kozub, Barbara; Bednarz, Sebastian; Bąk, Agnieszka; Melnychuk, Mykola; Masłoń, Adam
Geopolymers are binder materials that are produced by a chemical reaction between silica or aluminum compounds with an alkaline activating solution. Foamed geopolymer materials are increasingly being cited as a viable alternative to popular organic insulation materials. Since the foaming process of geopolymers is difficult to control, and any achievements in improving the performance of such materials are extremely beneficial, this paper presents the effect of the addition of basalt powder on the properties of foamed geopolymers. This paper presents the results of physicochemical studies of fly ash and basalt, as well as mechanical properties, thermal properties, and structure analysis of the finished foams. The scope of the tests included density tests, compressive strength tests, tests of the thermal conductivity coefficient using a plating apparatus, as well as microstructure tests through observations using light and scanning microscopy. Ground basalt was introduced in amounts ranging from 0 to 20% by mass. It was observed that the addition of basalt powder contributes to a reduction in and spheroidization of pores, which directly affect the density and pore morphology of the materials tested. The highest density of 357.3 kg/m3 was characterized by samples with a 5 wt.% basalt powder addition. Their density was 14% higher than the reference sample without basalt powder addition. Samples with 20 wt.% basalt addition had the lowest density, and the density averaged 307.4 kg/m3. Additionally, for the sample containing 5 wt.% basalt powder, the compressive strength exceeded 1.4 MPa, and the thermal conductivity coefficient was 0.1108 W/m × K. The effect of basalt powder in geopolymer foams can vary depending on many factors, such as its chemical composition, grain size, content, and physical properties. The addition of basalt above 10% causes a decrease in the significant properties of the geopolymer.
Determination of the Temperature Dependence of the Thermal Conductivity Coefficient of Plasma-Sprayed Coatings Based on Zirconium Dioxide in the Temperature Range up to 1100 °C
(2026) Zaichuk, Natalia; Borovyk, Dmytro; Yevdokymenko, Yurii; Kolotilo, Oleksandr; Frolov, Gennady; Terentiev, Oleksandr; Shymchuk, Serhiy
The temperature dependence of the thermal conductivity of plasma‑sprayed ZrO₂-5 wt.% CaO, (ZrO₂-5 wt.% CaO)-10 wt.% Ni, and (ZrO₂-5 wt.% CaO)-30 wt.% Ni coatings was investigated. A combined experimental and numerical approach was employed, comprising specimen heating with a propane–oxygen torch with in situ temperature field measurements and numerical simulation using COMSOL Multiphysics®. Thermal conductivity was calculated via an iterative solution of the inverse heat conduction problem. It was found that thermal conductivity increases with increasing Ni content: for the ZrO₂/CaO ceramic coating, thermal conductivity in the temperature range 20–1100°C ranged from 0.76 to 1.22 W·m⁻¹·K⁻¹, whereas for the metal–ceramic coatings containing 10% and 30% Ni, the values were 1.11–1.87 W·m⁻¹·K⁻¹ and 1.71–4.18 W·m⁻¹·K⁻¹, respectively. These results provide valuable insights for the design and optimization of thermal barrier coatings.
Advanced Geopolymer-Based Composites for Antimicrobial Application
(2023-11-29) Furtos, Gabriel; Prodan, Doina; Sarosi, Codruta; Moldovan, Marioara; Łach, Michał; Melnychuk, Mykola; Korniejenko, Kinga
In most studies about geopolymeric materials used in construction, the antibacterial properties of the building materials are treated as secondary features. Today, antimicrobial properties are a key feature in many building applications. The main objective of this article is to summarize the state-of-the-art in the area of design, development, and applications of nanoparticles as additives to geopolymer composites used in construction to improve their physical mechanical properties and induce a potential antibacterial effect, protecting them against alkali-resistant bacteria. On the basis of the literature and authors’ experience, the most important methods of obtaining especially the porous geopolymers, of nanomaterials used as additives, with potential antibacterial effect but also the potential mechanism of action against bacterial development were presented. The main findings show that using graphene oxide (GO) in geopolymer composites, but also other nanoparticles such as silver (Ag), zinc oxide (ZnO), silica (SiO2), titanium dioxide (TiO2), copper (Cu) as additives, is an effective way to induce a potential antibacterial effect and to improve the physical and mechanical properties in building materials.
Mechanical Properties of Hybrid Composites Based on Polypropylene Modified with Natural Fillers
(2023) Melnychuk, Mykola; Shevchuk, Igor; Kashytskyi, Vitalii; Feshcuk, Yurii; Polivoda, Nina
Hybrid composites based on a polymer matrix and a natural (renewable) filler can be one of the alternatives to widely used polymers. It is well known that natural fillers have poor adhesion to hydrophobic polymer matrices. In order to improve the interaction between hydrophilic fillers and hydrophobic matrix, fillers are usually pretreated with activators. Composites made by injection molding based on polypropylene and Kraft-lignin, microcellulose from hemp waste with filling from 9 to 27 wt % were investigated in work. In order to enhance the adhesion between the filler and the polymer, a special chemical treatment of the components was used with the addition of talc as a compatibilizing agent. Tensile and bending tests of the composites were carried out, as well as studies on the determination of microstructure features and evaluation of the influence of reinforcement and homogenization of mixtures using SEM. It was established that, compared to primary polypropylene, the flexural strength of composites with microcellulose practically did not change, Young’s modulus (E) increased to 12% depending on the degree of filling, and the flexural strength of composites with lignin increased to 42.3 MPa (32%), E up to 1570 MPa (22%). The tensile strength is practically unchanged for the cellulose filler and slightly increased to 10% for lignin, and Young’s modulus, depending on the type of filler and degree of filling, increased from 10 to 32%. Structure studies indicate a good interphase interaction of components in composites.
Оптимізація цифрових двійників модульних виробничих станцій FESTO
(Луцьк: ЛНТУ, 2025-02-12) Мисковець, Сергій Васильович; Фещук, Юрій, Петрович; Фещук, Максим, Юрійович; Півоварчук, Юрій, Арсенович
В роботі розглянуті питання створення, впровадження та оптимізації цифрових двійників модульних виробничих станцій FESTO. Шляхом моделювання досліджено роботу програмної та апаратної частини виробнич.
Корекції CAD моделей для оптимізації процесів 3D друку
(Луцьк: ЛНТУ, 2025-02-12) Мисковець, Сергій Васильович; Гусачук, Дмитро Анатолійович; Кашицький, Віталій, Павлович; Парфентьєва, Інна, Олександрівна
В роботі розглянуті питання покращення якості та функціональності виробів, отриманих з використанням технологій FDM друку. На основі досліджень впливу геометричних параметрів цифрових моделей на якість формоутворення деталей запропоновано метод корекції їх конфігурації на стадії їх підготовки.

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