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1

Surface and mechanical properties of plasma-modified chitosan/polyvinyl alcohol composite films

Chang Shih-Hang, Chang Yuan-Hsuan

Polimery

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2025

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Vol. 70, nr 3

177--185

EN

The surface and mechanical properties of chitosan/polyvinyl alcohol (CS/PVA) composite films modified with O2 and N2 plasma were investigated. The FT-IR method confirmed the presence of characteristic bands originating from both CS and PVA, the intensity of which significantly increased after plasma modification. Plasma treatment also increased the hydrophilicity of CS/PVA films, with a slight decrease in their surface smoothness. In addition, plasma modification reduced the adhesion of bovine serum albumin. The highest fracture toughness and the lowest adhesion of bovine serum albumin were obtained for CS/PVA films (1/3 wt%/wt%). The conducted studies confirmed the possibility of biomedical applications of chitosan/polyvinyl alcohol composite films.

PL

Zbadano właściwości powierzchniowe i mechaniczne folii kompozytowych chitozan/alkohol poliwinylowy (CS/PVA) modyfikowanych plazmą O2 i N2. Metodą FT-IR potwierdzono obecność charakterystycznych pasm pochodzących zarówno od CS, jak i PVA, których intensywność znacząco zwiększyła się po modyfikacji plazmą. Działanie plazmy zwiększyło również hydrofilowość folii CS/PVA, przy niewielkim zmniejszeniu gładkości ich powierzchni. Ponadto modyfikacja plazmą zmniejszyła adhezję albuminy surowicy bydlęcej. Największą wytrzymałość na pękanie i najmniejszą adhezję albuminy surowicy bydlęcej uzyskano w przypadku folii CS/PVA (1/3 % mas./% mas.). Przeprowadzone badania potwierdziły możliwość biomedycznych zastosowań folii kompozytowych chitozan/alkohol poliwinylowy.

2

Polypropylene composites with natural carbon fillers obtained by rotational molding

Szymańska Joanna, Szostak Marek, Paukszta Dominik

Polimery

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2025

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Vol. 70, nr 5

313--321

EN

PP composites with different contents of natural/waste carbon filler (1, 5, 10 and 25 wt.%) were obtained by rotational molding. Thermal properties (DSC), tensile properties and structure (optical and digital microscopy, WAXS) of PP composites were assessed. It was found that the composites are charac-terized by good surface quality of external walls and usually poorer quality of internal walls. The filler content affects both the degree of crystallinity and the mechanical properties of PP.

PL

Kompozyty PP o różnej zawartości naturalnego/odpadowego napełniacza węglowego (1, 5, 10 oraz 25% mas.) otrzymano metodą formowania rotacyjnego. Dokonano oceny właściwości termicz¬nych (DSC), właściwości mechanicznych przy rozciąganiu i struktury (mikroskopia optyczna i cyfrowa, WAXS) kompozytów PP. Stwierdzono, że kompozyty charakteryzują się dobrą jakością powierzchni ścian zewnętrznych oraz zazwyczaj słabszą ścian wewnętrznych. Zawartość napełniacza ma wpływ zarówno na stopień krystaliczności, jak i na ich właściwości mechaniczne PP.

3

PET composites and their applications in the face of green chemistry challenges - an overview

Ostrowski Krzysztof Adam, Spyrowski Mariusz, Romańska Paulina, Majka Tomasz M., Piech Radosław, Zawadzka Zuzanna, Furtak Kazimierz, Bednarowski Dariusz

Polimery

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2025

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Vol. 70, nr 4

227--239

EN

The review discusses the recycling of PET packaging, highlighting its significance in the circular economy. It presents methods for processing the recovered material and its potential applications in various sectors of the economy. The importance of the 6R principle in integrating the economy and promoting sustainable development is also emphasized.

PL

W artykule omówiono recykling opakowań PET, podkreślając jego znaczenie w gospodarce obiegu zamkniętego. Przedstawiono metody przetwórstwa odzyskanego materiału i jego potencjalne zastosowania w różnych sektorach gospodarki. Wykazano znaczenie zasady 6R w integracji gospodarki i promowaniu zrównoważonego rozwoju.

4

Management of waste fly ash as an epoxy resin filler

Szymańska Joanna, Tomczak Dorota, Przesławski Grzegorz, Borysiak Sławomir

Polimery

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2025

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Vol. 70, nr 1

40--49

EN

Epoxy resin composites with the addition of 20-50 wt.% of ash from municipal waste incineration were obtained. The curing kinetics of the composites (DSC) was determined, and the activation energy was calculated using the Kissinger and Ozawa method. In addition, flexural properties, and impact strength, as well as the structure of the composites (XRD, optical microscopy) were investigated. Brittles of the composites increased with increasing the filler content. The addition of ash also affected the kinetics of the resin cross-linking reaction. A change in the activation energy, degree of conversion and cross-linking time was observed.

PL

Otrzymano kompozyty żywicy epoksydowej z dodatkiem 20-50% mas. popiołu ze spalania odpadów komunalnych. Określono kinetykę utwardzania kompozytów i stopień konwersji (DSC), a energię aktywacji obliczono metodą Kissingera i Ozawy. Ponadto zbadano właściwości mechaniczne przy zginaniu i udarność, a także strukturę kompozytów (XRD, mikroskopia optyczna). Kruchość kompozytów zwiększała się wraz ze wzrostem zawartości napełniacza. Dodatek popiołu wpływał również na kinetykę reakcji sieciowania żywicy. Zaobserwowano zmianę energii aktywacji, stopnia konwersji i czasu sieciowania.

5

Flax fiber reinforced PET-G composites with improved interfacial adhesion

Hartung David, Seidlitz Holger, Osiecki Tomasz, Sztorch Bogna, Przekop Robert E., Kazimierczuk Magdalena

Polimery

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2025

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Vol. 70, nr 2

113--123

EN

Recycled PET-G (rPET-G) composites reinforced with flax fiber were obtained. To improve interfacial adhesion, the fiber was treated by washing and finishing with bio-based epoxidized soybean oil and admixture acid. The effect of fiber surface treatment on its properties and those of the composites was evaluated by TGA, FT-IR and SEM, as well as by contact angle, flexural and tensile measurements. The results indicated delayed degradation of the treated flax fiber with a fiber mass loss of about 4 wt%. The flexural strength and modulus increased for the washed and finished flax fiber compared to the untreated one. While the tensile properties were influenced by structural effects resulting from the fiber treatment. These findings contribute to the development of more sustainable and high-performance natural fiber-reinforced thermoplastic composites.

PL

Otrzymano kompozyty PET-G z recyklingu (rPET-G) wzmocnione włóknem lnianym. Aby poprawić oddziaływania międzyfazowe, włókno poddano obróbce przez mycie i wykończenie na bazie biologicznej epoksydowanym olejem sojowym i kwasem admerginowym. Wpływ obróbki powierzchni włókna na jego właściwości i właściwości kompozytów oceniano za pomocą TGA, FT-IR i SEM, a także pomiarów kąta zwilżania, właściwości mechanicznych przy zginaniu i rozciąganiu. Wyniki wskazały na opóźnioną degradację poddanego obróbce włókna lnianego z utratą masy włókna wynoszącą ok. 4% mas. Wytrzymałość na zginanie i moduł sprężystości wzrosły w przypadku umytego i wykończonego włókna lnianego w porównaniu z niepoddanym obróbce. Natomiast właściwości mechaniczne przy rozciąganiu zależały od efektów strukturalnych wynikających z zastosowanej obróbki włókna.

6

Energy-efficient propeller-driven climbing robot design based on glass-fiber reinforced polymer

Abouhussein Omar Abdelaziz, Fouly Ahmed

Polimery

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2025

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Vol. 70, nr 7-8

455--466

EN

Three techniques were investigated to optimize the performance of a propeller-driven climbing robot: i) materials optimization using glass fiber reinforced polymer (GFRP) laminates with three distinct configurations - symmetric cross-layer (0°/90°), antisymmetric cross-layer (0°/90°), and antisymmetric angle-layer (±45°), ii) optimization of the robot chassis structural topology using density-based methods, and iii) laminate thickness (0.5-3.0 mm) and fiber content (50-70 v%). Optimal performance was achieved for an antisymmetric angle-layer configuration of 2.2 mm with 60 v% fiber content, resulting in a weight reduction (6.8%). Combined with a topologically optimized chassis design (20.1% weight reduction), the entire system achieves a 23.5% weight reduction, which translates into energy savings (23.6% torque reduction and 17.3% thrust reduction) while maintaining structural integrity. These results set a new standard for energy-efficient climbing robot designs, thanks to the synergistic optimization of materials and structures.

PL

Z badano trzy techniki w celu optymalizacji wydajności napędzanego śmigłem robota wspinaczkowego: i) optymalizacja materiałów przy użyciu laminatów na bazie wzmocnionego włóknem szklanym polimeru (GFRP) o trzech konfiguracjach - symetrycznej warstwie poprzecznej (0°/90°), antysymetrycznej warstwie poprzecznej (0°/90°) i antysymetrycznej warstwie kątowej (±45°), ii) optymalizacja topologii strukturalnej podwozia robota przy użyciu metod opartych na gęstości oraz iii) grubości laminatu (0,5-3,0 mm) i zawartości włókien (50-70 v%). Optymalną wydajność uzyskano dla antysymetrycznej konfiguracji warstwy kątowej 2,2 mm z zawartością włókien 60 v%, co skutkowało redukcją masy (6,8%). W połączeniu z topologicznie zoptymalizowaną konstrukcją podwozia (redukcja masy o 20,1%) cały system osiągnął 23,5% redukcję masy, co przekłada się na oszczędność energii (redukcja momentu obrotowego o 23,6% i redukcja ciągu o 17,3%) przy zachowaniu integralności struktury. Wyniki te wyznaczają nowy standard w dziedzinie energooszczędnych konstrukcji robotów wspinaczkowych, dzięki synergicznej optymalizacji materiałów i konstrukcji.

7

Rheological characteristics of composites based on carboxymethyl chitosan

Lewandowska Katarzyna, Lewandowska Sandra

Engineering of Biomaterials

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2025

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vol. 28, no. 173

art. no. 01

EN

Composite formation is a widely used method to modify polymer performance because such systems can combine the advantageous properties of each ingredient. This research evaluates the rheological properties and structure of biopolymer composites based on carboxymethyl chitosan (CMCS), with various additions of an aqueous dispersion of α-chitin (ChA) and glycerin (GLY). Composites containing carboxymethyl chitosan, α-chitin dispersion, and glycerin are designed for potential cosmetic and/or biomedical applications. The rheological properties of carboxymethyl chitosan, α-chitin aqueous dispersion, and their mixtures were determined using a ROTAVISC lo-vi Complete rotational viscometer in the temperature range of 25-40ºC and under various shear rates (1.3-33 s-1). The activation energy of the viscous flow and the rheological parameters from the power law were calculated and analyzed using Arrhenius plots and flow curves, respectively. As part of this investigation, composite films were prepared and characterized using infrared analysis. The studies conducted classified the prepared systems as non-Newtonian liquids that exhibit a shear-thinning effect (i.e. typical pseudoplastic fluids). The results revealed that the introduction of chitin whiskers as an aqueous dispersion into the CMCS matrix significantly altered the rheological properties of the tested composites. These changes were attributed to the mutual interactions between the polymer components and the low-molecular-weight additives.

8

Design and development of multilayered functionalized artificial skin for prosthetic applications: a biomimetic approach

Adamczyk Dominika, Szatkowski Piotr, Grałek Oliwia, Frohlich Martyna, Matysek Justyna

Engineering of Biomaterials

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2025

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vol. 28, no. 173

art. no. 12

EN

The development of artificial skin for prosthetic applications poses a significant engineering challenge due to the need to replicate human skin's multilayered architecture and multifunctionality. Each layer must be engineered to mimic distinct skin functions including mechanical protection, thermal regulation, tactile sensation, and structural support. Additionally, the artificial skin must demonstrate biocompatibility, long-term durability, and seamless integration with prosthetic devices to provide users with enhanced sensory feedback and improved quality of life. This study aims to design and fabricate a low-cost, biomimetic four-layer artificial skin system using functionalized silicon composites to replicate human skin's multilayered architecture and multifunctional properties for prosthetic applications. The four-layer structure includes: a surface biomimetic porous layer for mechanical shielding, a thermal management layer enhanced with boron nitride fillers to improve heat conduction, a conductive sensing layer containing carbon nanotubes for pressure detection, and a base layer providing cushioning and structural integrity. Each layer was specifically engineered to mimic different skin functions: mechanical protection, thermal regulation, tactile sensation, and structural support. The total thickness of the fabricated layers matches the human skin thickness values. Mechanical characterization revealed properties compatible with prosthetic applications, while surface analysis confirmed successful texture modification for enhanced tactile interaction. The thermal layer demonstrated improved heat distribution capabilities, and the conductive layer showed potential for pressure sensing applications. This work presents a complete design approach for artificial skin that meets both appearance and functional needs for prosthetics. The developed system offers promising prospects for enhancing quality of life for amputees through improved sensory feedback and thermal comfort.

9

Gradient Al2O3-Ni composites for aggressive substance transport: a novel approach using centrifugal gel casting

Zygmuntowicz Justyna, Tańska Joanna, Wiecińska Paulina, Piotrkiewicz Paulina, Konopka Katarzyna, Szafran Mikołaj, Wachowski Marcin, Michalski Bartosz, Kaszuwara Waldemar

Composites Theory and Practice

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2025

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R. 25, nr 2

144-156

EN

This study focuses on the development and characterization of Al2O3-Ni composite materials designed for use in environments where high corrosion resistance and mechanical strength are critical. The composites were formed using the centrifugal gel casting method to produce pipes with a gradient structure. The inner layer of the pipes consisted mainly of Al2O3, while the outer layer incorporated nickel particles. Rheological, thermogravimetric, and microstructural analyses were conducted to optimize the composite's formulation and processing conditions. The results showed that a monomer content of 3% by weight of 2-hydroxyethyl acrylate (HEA) provided an optimal balance between workability and polymer network formation. Corrosion tests revealed that while the alumina-rich inner layer exhibited good chemical resistance, the presence of nickel particles on the surface led to localized corrosion, particularly in acidic environments. The findings indicate that further refinement of the casting process is necessary to improve the distribution of the nickel particles and enhance the material's overall corrosion resistance.

10

Development of the properties of magnesia alumina spinel-based refractory composites with modifying oxides

Bąk Aleksandra, Surówka Bartosz, Prorok Ryszard, Madej Dominika

Composites Theory and Practice

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2025

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R. 25, nr 3

166--180

EN

The present study investigates the synthesis of MgAl2O4 spinel via one-step sintering, producing a reference sample without additives and four additional samples containing 5 wt% ZrO2, Fe2O3, SiO2, or TiO2, respectively. The MA sample along with the four types of modified spinel-based composites [MA_5T, MA_5Z, MA_5F, MA_5S] were characterized in terms of their phase composition, microstructure, bulk and true densities, as well as open and true porosities of the sintered materials. High-temperature microscopy was employed to evaluate dimensional changes of the samples during their heat treatment process. The presence of phases and the firing behavior of the resulting composite materials were evaluated using thermodynamic simulation (FactSage 8.3). The study demonstrated that the incorporation of specific oxide additives significantly influences the synthesis and properties of MgAl₂O₄ spinel. Iron (Fe³⁺) and titanium (Ti⁴⁺) ions were found to induce structural modifications within the spinel lattice, suggesting partial substitution or incorporation into the crystal framework. XRD analysis showed that the addition of the SiO₂ modifier leads to the formation of Mg₂SiO₄, which can partially dissolve into the spinel phase, while ZrO₂ promoted the extraction of Al³⁺ ions from the spinel structure, as corroborated by the thermochemical simulations using FactSage. The highest microstructural densification was achieved in the samples with TiO₂ and SiO₂, indicating their positive role in enhancing sintering efficiency. Conversely, the addition of Fe₂O₃ did not significantly affect the densification behavior, despite the formation of an Fe-rich spinel phase.

11

Al₂O₃-Ni composites: impact of cooling on composites in centrifugal gel casting

Zygmuntowicz Justyna, Tańska Joanna, Wiecińska Paulina, Piotrkiewicz Paulina, Konopka Katarzyna, Szafran Mikołaj, Wachowski Marcin, Szachogłuchowicz Ireneusz, Kaszuwara Waldemar

Composites Theory and Practice

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2025

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R. 25, nr 2

113-122

EN

This study investigates the influence of polymerization kinetics and the processing sequence on the microstructure and mechanical performance of Al₂O₃-Ni composites fabricated via centrifugal gel casting. Two fabrication approaches were compared, differing in the sequence of component addition and the temperature of the casting mass. The optimized method, involving cooling the suspension to below 5°C prior to the addition of nickel powder and the polymerization initiator, significantly extended the gelation idle time from 225 s to 475 s, allowing improved control over polymerization and particle dispersion. As a result, the microstructure exhibited enhanced phase homogeneity and reduced porosity. Compression tests demonstrated substantial enhancement in mechanical performance: the compres sive strength increased from 22 MPa in the non-optimized series to 185 MPa in the optimized series, representing more than an eightfold improvement. These findings highlight a practical strategy for tuning the polymerization behavior to engineer high-performance ceramic-metal composites with potential applications in structural and functional components.

12

Influence of the metal phase of novel Al2O3/TiO2/TiAl2O5 composites obtained via the slip casting method

Wachowski Marcin, Zygmuntowicz Justyna, Kosturek Robert, Śnieżek Lucjan, Piotrkiewicz Paulina, Żurowski Radosław, Korycka Karolina

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

|

Vol. 73, nr 1

art. no. e152213

EN

This study aims to analyze the ceramic-metal composite Al2O3/TiO2/TiAl2O5 obtained using the slip-casting method. Samples containing 50% of the solid phase and 2% and 4% fractions of the metallic phase were examined. Rheological investigations were performed. Measurements of shrinkage and density of the composites produced were determined. The phase composition of the obtained composite was investigated using SEM/EDS and XRD techniques. Stereological analysis was performed as well. The slip-casting method enables the production of the proposed composite, reinforced by the presence of TiO2 and TiAl2O5. With the increase in the content of the metallic phase in the composite, the thialite phase content increases, but relative density and volumetric shrinkage of the obtained composites both decrease. Thialite grains are characterized by a size in the range of 4 µm to 15 µm, which leads to a low density of the samples. The results revealed that no significant effect of changing the metal phase content of the slurries used for the composites being fabricated was observed on the limiting grain growth of alumina during the sintering process of slip-casting composites. This finding is important as it suggests that the increase in metallic phase content does not lead to undesirable grain coarsening, which could degrade mechanical properties.

13

Wybrane metody badań nieniszczących wykorzystywane podczas inspekcji uszkodzonych struktur kompozytowych przed i po naprawie

Szymański Rafał

Badania Nieniszczące i Diagnostyka

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2025

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nr 1-3

33--45

PL

Artykuł wpisuje się we współczesne zainteresowania firm z branży lotniczej. W artykule wymieniono najczęstsze niezgodności występujące w strukturach kompozytowych powstające na etapie produkcyjnym oraz eksploatacyjnym. W pracy skupiono się na uszkodzeniu wywołanym uderzeniem, które jest najczęstszym typem uszkodzenia podczas eksploatacji samolotów. Przybliżono również ogólne podejście do przeprowadzenia inspekcji w celu identyfikacji uszkodzenia oraz naprawy uszkodzenia. Badania opisane w artykule przeprowadzono na płaskich płytach kompozytowych (polimerowo węglowych) o strukturze monolitycznej i przekładkowej. Zarówno do wykrycia uszkodzeń w kompozycie węglowym oraz weryfikacji naprawy, wykorzystano metodę wizualną, tap-test, termografię oraz ultradźwiękową (Phased Array). Na podstawie otrzymanych wyników określono skuteczność wykrywania uszkodzeń oraz możliwości weryfikacji naprawionych struktur dla każdej z wykorzystanej w badaniach metody nieniszczącej.

EN

The article is in line with the contemporary interests of aerospace companies. The article lists the most common incompatibilities occurring in composite structures arising at the manufacturing and operational stages. The paper focuses on impact damage, which is the most common type of damage during aircraft operations. It also approximates a general approach to conducting an inspection to identify the damage and repair the damage. The tests described in the article were conducted on flat composite (polymer-carbon) plates with monolithic and sandwich structures. Both visual, tap-test, thermography and ultrasonic (Phased Array) methods were used to detect damage in the carbon composite and verify repair. Based on the results obtained, the effectiveness of damage detection and the ability to verify repaired structures were determined for each nondestructive method used in the study.

14

Enhanced microstructure and mechanical properties of Al2O3-Ni composites via centrifugal slip casting with constant magnetic field

Zygmuntowicz Justyna, Kosiorek Magdalena, Wachowski Marcin, Torzewski Janusz, Szachogluchowicz I., Zielińska Paulina, Kaszuwara Waldemar, Falkowski Paweł

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 8

232--248

EN

This study investigates the fabrication and properties of Al2O3-Ni composites produced by centrifugal slip casting under a constant external magnetic field, aiming to optimize particle alignment and distribution for enhanced material performance. The research compares two series of samples made with nickel powders from Sigma Aldrich and Alfa Aesar. Series I exhibited non-uniform nickel particle distribution, while Series II demonstrated a more uniform dispersion and consistent particle size, likely due to improved alignment under the magnetic field. The optimal results from compression tests revealed that Series II achieved a compressive strength of 410 MPa, roughly twenty times greater than Series I, highlighting the effectiveness of the magnetic field in enhancing the microstructure and mechanical properties. These findings suggest that centrifugal slip casting with a constant magnetic field holds significant potential for applications in aerospace and electronics, where robust material performance under extreme conditions is required.

15

Effect of matrix modification of sandwich composite on selected strength propertises

Masiewicz Joanna, Przybyłek Paweł, Szczepaniak Robert, Kostrzewa Marcin

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 9

203--213

EN

Improvements in materials and the availability of apparatus enabling mechanical, strength, thermal testing of sandwich structures, including fatigue tests, allow for a dynamic development of research work confirming the effectiveness of the use of structural composites as energy-intensive structures. This paper presents the results of selected strength tests of a layered epoxy-glass composite with a polyurethane-modified matrix and a porous core. The conducted experimental studies were proposed as a basis for the creation of a test procedure for comprehensive strength and mechanical characterisation of the composite. Obtaining a layered material with a modified matrix is a formative factor for impact energy absorption properties. The quantitative and qualitative effects of material selection and matrix modification on impact properties were characterised, and an analysis of composite damage and component interaction under loads occurring during the proposed experimental tests was carried out.

16

Characterization of EN-AW-6061-O–graphite nanoflake composites for enhanced mechanical properties using multi-pass friction stir processing

Patil Namdev Ashok, Pedapati Srinivasa Rao, Kakkeri Shrishail, Pedapati Santoshi

Advances in Materials Science

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2025

|

Vol. 25, nr 3(85)

5--17

EN

In this study, graphite (Gr) nano flakes dispersion with increasing number of passes (1, 2, and 3) inside the resultant aluminium ENAW-6061-O-Gr composites using Friction Stir Processing (FSP) has been accomplished successfully. The objectives were to embed the Gr nanoflakes inside ENAW-6061-O-Gr composites, investigate the effect of number of FSP passes on the mechanical properties of aluminium 6061/graphite composites. The ENAW-6061-O-Gr composite samples were evaluated with tensile tests and elemental analysis through SEM with EDX and mapping. The dispersion and presence of graphite particles is confirmed. Multi-pass FSP improved the tensile strength of the ENAW-6061-O-Gr composites. The UTS of C3-Composite processed with three passes is 153.65 MPa, that is 24% of improvement compared to the unreinforced aluminium ENAW-6061-O base metal alloy.

17

Preparation and use of alginate-based composites with the addition of graphene oxide for the removal of divalent metal ions from aqueous solutions

Fryczkowska Beata, Zaręba Piotr

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

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2024

|

Nr 92 (tom 1)

85--101

EN

Industrial wastewater contains heavy metals such as zinc, copper, lead, chromium, nickel, cadmium, arsenic, cobalt and mercury and is one of the types of sewage that negatively affect the environment. Metal ions can be removed using various types of sorbents. An interesting solution are polysaccharide-based sorbents. This paper presents research on the preparation and use of granules based on 2% alginate with the addition of 2.81% graphene oxide as sorbents of the following ions: Ni2+, Co2+, Cu2+, Pb2+ and Cd2+. Graphene oxide / alginate solutions, containing from 0.18% to 5.62% of GO, were prepared for the tests. Granules were formed by coagulating successive alginate solutions in 2.5% CaCl2 (Method 1). The possibility of introducing alginate solutions directly into solutions containing metal ions was also tested (Method 2). As a result of the study, it was observed that the use of ready-made sorbent (Method 1) allows the removal of ~ 30% of the contamination within 30 to 60 minutes. This method turned out to be the most effective for removing Ni2+, Co2+ and Cu2+ ions. The use of a simplified procedure (Method 2), on the other hand, allows the removal of all tested metal ions in amounts ranging from 5% (Cd2+) to 25% (Co2+).

18

Numerical analysis of temperature distributions in glulam beams exposed to fire and reinforced with aramid composite

Jończyk Damian, Hajdas Damian, Major Maciej

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

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2024

|

Nr 91 (tom 1)

7--21

EN

Currently, strengthening timber elements with the use of various materials has become popular. Reinforcements are used to repair existing elements or improve the static operating characteristics of new elements. Fibre composites are being increasingly used as reinforcement. Investigations have shown that the use of fibre composites influences the nature of static work. However, an under-researched issue is the determination of the influence of composite reinforcement on temperature distributions and, consequently, the depth and shape of charring in the cross-section during a fire. The article presents a numerical thermal analysis of cross-sections of glulam beams reinforced with aramid materials in various forms. Fire action was assumed in accordance with the ISO fire curve and the fire load on three of the four edges of the beams was modelled. Temperature distributions are presented for all analysed cases, which shows the beneficial effect of the use of aramid reinforcement on the temperature distribution in the cross-section during a fire.

19

Review of modern methods of timber strengthening

Dygas Justyna

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2024

|

Z. 30 (180)

35--45

EN

The aim of this review paper is to present modern methods of strengthening timber structures. The first part of the article discusses the characteristics of timber. It needs to be strengthened for several reasons, as described below. The following points describe the strengthening of the components with the use of steel and composite materials. The focus is placed on composite bars, strips and sheets. The materials industry is particularly interested in composites. The work showed their general characteristics and analysed how to use them to reinforce the structure in the best manner. The analysis of the conducted studies suggests that the application of the aforementioned elements is reasonable, and scientists are planning additional research in this domain.

PL

Celem tej pracy przeglądowej było przedstawienie nowoczesnych sposobów wzmacniania konstrukcji drewnianych. W pierwszej części artykułu skupiono się na charakterystyce drewna. Jego wzmacnianie jest konieczne ze względu na szereg przyczyn, które omówiono w niniejszej pracy. W kolejnych punktach opisano wzmacnianie elementów za pomocą stali oraz kompozytów. Szczególną uwagę poświęcono prętom, taśmom i matom kompozytowym. Widoczne jest duże zainteresowanie kompozytami w branży materiałowej. Przedstawiono ich ogólną charakterystykę oraz przeanalizowano ich użyteczność we wzmacnianiu konstrukcji. Z badań wynika, że zastosowanie wyżej wymienionych elementów jest zasadne, a naukowcy planują dalsze badania w tym zakresie.

20

Synteza i zastosowanie modyfikowanych nanorurek TiO2

Górzyński Daniel, Nadolna Joanna, Kozak Magda, Mazierski Paweł

Wiadomości Chemiczne

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2024

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[Z] 78, 3-4

171--188

EN

Heterogeneous photocatalysis in the presence of semiconductor materials, especially TiO2, is increasingly studied due to its potential application in hydrogen generation, carbon dioxide conversion, and pollutant degradation. TiO2, known for its cost-effectiveness, stability, and safety, is particularly effective in its nanometric form, with nanotubes standing out for their structure that improves light absorption and charge carrier mobility. One approach to improve the properties of TiO2 for its application in photocatalytic processes involves its modification. Modifications of TiO2 nanotubes aim to reduce the rate of recombination of photogenerated charge carriers, increase photocatalytic activity in the UV range, extend its activity to the visible radiation range, and enhance reaction selectivity. Enhancing TiO2 photocatalytic efficiency involves modifications such as doping, creating heterojunctions, and introducing structural defects. The objective of this mini-review is to present selected methods of modifying TiO2 nanotubes obtained through anodic oxidation, leading to the enhancement of their photocatalytic properties.