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1

Hydrożelowe okłady łagodzące objawy migreny

Piłat Edyta, Krysiak Natalia, Gawrycka Pola, Gnatowski Przemysław, Kucińska-Lipka Justyna

Wiadomości Chemiczne

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2025

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[Z] 79, 7-8

539--558

EN

Migraine is a chronic neurological disorder that directly affects up to one billion people worldwide. Current treatments for migraine involve acute treatment, including the use of analgesics, nonsteroidal anti-inflammatory drugs, triptans, and preventive treatment. One of the currently available solution relieving migraine symptoms is hydrogel patches. They typically provide a cooling effect due to the presence of an active substance, most commonly menthol. Unfortunately, despite menthol's undeniable advantages in cooling applications, its intense smell may be irritating for people with migraines, who suffer from olfactory hypersensitivity. Therefore, the following work proposes a novel solution that combines the benefits of hydrogels with a natural extract of feverfew, which is described in the literature as effective in relieving headaches, including migraines. In this study, hydrogel patches were developed based on a natural polymer and modified with feverfew extract. The physicochemical properties of the resulting materials were investigated, including swelling behavior, surface wettability, and substance release from the polymer matrix. The potential for use in the intended application was preliminarily assessed as possible, but requiring further studies.

2

Synthesis and characterization of methacrylamide- -based molecularly imprinted polymers for detection of di(2-ethylhexyl) phthalate

Fauziah St, Soekamto Nunuk Hariani, Paulina Taba, Hustim Muralia, Achman Annisyah Aprilia, Andekan Nital, Husain Husnia Paraditha, Sapar Ajuk

Polimery

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2025

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Vol. 70, nr 6

386--393

EN

Based on methacrylamide (MAM) and trimethylolpropane trimethacrylate (TRIM) as a cross-linking agent, molecularly imprinted polymers (MIPs) were obtained by precipitation polymerization and used for the detection of di(2-ethylhexyl)phthalate (DEHP) in drinking water in plastic packaging. The presence of functional groups –NH, –CH, –C=O, –C=C and –CO was confirmed by FT-IR. The formation of MIP_DEHP was also confirmed by EDS. Moreover, SAA analysis showed their mesoporous structure. The adsorption capacity was consistent with the isothermal Freundlich adsorption model, and the adsorption kinetics models with a pseudo-second-order reaction. Small, uniform, porous grains were observed in the MIP structure (SEM).

PL

Na bazie metakryloamidu (MAM) i trimetakrylanu trimetylopropanu (TRIM) jako środka sieciującego, metodą polimeryzacji strąceniowej, otrzymano polimery z nadrukiem molekularnym (MIP), które użyto do wykrywania di(2-etyloheksylo)ftalanu (DEHP) w wodzie pitnej w opakowaniach plastikowych. Obecność grup funkcyjnych –NH, –CH, –C=O, –C=C i –CO potwierdzono metodą FT-IR. Powstawanie MIP_DEHP potwierdzono również metodą EDS. Ponadto analiza SAA wykazała ich mezoporowatą strukturę. Pojemność adsorpcyjna była zgodna z izotermicznym modelem adsorpcji Freundlicha, a modele kinetyki adsorpcji z reakcją pseudodrugiego rzędu. W strukturze MIP zaobserwowano małe, jednolite, porowate ziarna (SEM).

3

The effect of mechanical properties on polymer deformation and flow suspension in the Selective Laser Sintering process

Belgada Rihabe, Zarbane Khalid, Mzerd Ahmed

International Journal of Applied Mechanics and Engineering

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2025

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Vol. 30, no. 1

21--35

EN

Among the various additive manufacturing processes, there is selective laser sintering, with the use of a high-power laser that sinters the small particles of polymer powder and turn them into a solid structure, from a 3D model, nowadays SLS additive manufacturing has become the best choice for the industry, especially for polymer materials, SLS ensures high productivity and well-honed materials at low cost. Recent Advances in Fitting, the materials and software have made SLS printing accessible to a wider range of activities. Our study is to show the mechanism of polymer particle suspension during the three stages of SLS printing, we start with printing first, the polymer powder in a thin layer applied on a flat shape inside the build chamber and the printer will heat the powder until the polymer melts, Allowing the laser to easily increase the temperature in specific areas in the powder bed to trace the morphology of the solidified part. Secondly, cooling and finally post-processing to extract the finished parts from the build chamber. In our study, we will analyze the suspension of small polymer powder particles in the SLS printing process. We will start with the mathematical formulation of the problem with an experimental study of the polymer sample studied. Next, we will set up the chosen solution method and finally the modeling of the results obtained on the FORTRAN language.

4

Otrzymywanie polimeru sulfonamidowego oraz jego wpływ na efektywność mielenia cementu

Ke Kai, Yu Han, Li Xiang, Zhao Jun-hao, Lyv Yang, Li Xiang-guo

Cement Wapno Beton

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2025

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R. 30, nr 2

110--123

PL

Efektywne mielenie stanowi jedno z kluczowych narzędzi ograniczania zużycia energii w produkcji cementu, a projektowanie wysokoefektywnych środków wspomagających mielenie w oparciu o koncepcję projektowania struktury molekularnej stanowi obecnie istotny kierunek badań. W niniejszej pracy zastosowano kwas 2-akrylamido-2-metylo-propanosulfonowy [AMPS], akrylan hydroksypropylu [HPA] oraz monoeter winylowy glikolu dietylowego [DEGVE] jako monomery do syntezy nowego polimeru o małej masie cząsteczkowej. Następnie, poprzez wprowadzenie polioli polimerowych, opracowano polimerowy środek wspomagający mielenie klinkieru cementowego, a jego relację struktura-aktywność poddano systematycznej ocenie. Wyniki badań wykazały, że optymalne właściwości uzyskuje się przy zawartości inicjatora i regulatora długości łańcucha wynoszącej odpowiednio 1,39% oraz 5,84%, przy stosunku molowym nDEGVE: nAMPS: nHPA równym 1 : 1,85 : 0,5. Należy podkreślić, że ostateczna skuteczność procesu mielenia określana jest na podstawie wartości D50 oraz pozostałości na sicie o oczkach 45 μm, a nie poprzez powierzchnię właściwą cząstek czy intensywność hydratacji cementu, które nie stanowią głównych wskaźników oceny wydajności mielenia. W porównaniu z tradycyjnymi środkami wspomagającymi mielenie na bazie alkanoloamin, opracowany polimerowy dodatek pozwolił na istotną optymalizację rozkładu wielkości cząstek cementu. Udział objętościowy frakcji 0-32 μm oraz >64 μm uległ ograniczeniu odpowiednio o 1,5% i 51,7%, natomiast udział frakcji 32-64 μm zwiększył się o 59,5%. Ponadto, w odniesieniu do środków na bazie alkanoloamin, wytrzymałość na ściskanie cementu po 3 dniach zwiększyła się o 3,4%, a po 28 dniach o 8,3%.

EN

Efficient grinding is one of the important means to reduce energy consumption in cement production, and the development of efficient grinding aids based on molecular structure design is currently a research hotspot. In this work, 2-acrylamido-2-methylpropanesulfonic acid [AMPS], hydroxypropyl acrylate [HPA], and diethylene glycol monovinyl ether [DEGVE] as monomers was applied to synthesize a novel low molecular weight polymer. A polymer-based grinding aid for cement clinker was prepared by incorporating polymeric polylol, and its structure-activity relationship was systematically evaluated. The results showed that the optimal performance was achieved when the amounts of initiator and chain transfer agent were 1.39 % and 5.84 %, respectively, and the ratio of nDEGVE : nAMPS : nHPA was 1:1.85:0.5. It should be noted that the optimal grinding performance is determined by the D50 value and the 45 μm sieve residue, not by the particle specific surface area or the strength of cement hydration, which are not the primary indicators for evaluating grinding performance. Compared with alcohol amine grinding aids, the prepared grinding aid could significantly optimize particle size distribution of cement. The volume fraction of particles above 0-32 μm and 64 μm was decreased by 1.5 % and 51.7 %, respectively, while increased by 59.5 % for 32-64 μm; Compared with the alcohol amine grinding aid, the compressive strength of cement at 3 d and 28 d increased by 3.4 % and 8.3 %, respectively.

5

Przydatność polimerów stosowanych w technologii druku 3D do budowy modeli doświadczalnych służących do badań dynamicznych na stole wstrząsowym

Dulińska Joanna, Boroń Paweł, Tatara Tadeusz, Budzik Grzegorz, Przeszłowski Łukasz

Materiały Budowlane

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2024

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nr 1

17--22

PL

Technologia druku 3D ma coraz większe zastosowanie w budownictwie. W artykule zaprezentowano ocenę przydatności wybranych polimerów do druku modeli laboratoryjnych służących do identyfikacji częstotliwości drgań własnych obiektów na stole wstrząsowym. Wyznaczono doświadczalnie parametry fizykomechaniczne polimerów, a także obliczono skale podobieństwa w przypadku modeli wydrukowanych z analizowanych polimerów. Wskazano na parametry materiałowe polimerów warunkujące możliwość i zasadność ich stosowania w badaniach dynamicznych na stole wstrząsowym.

EN

3D printing technology is gradually becoming more employed in civil engineering. The article assesses the suitability of selected polymers for printing laboratory models used to identify the natural frequencies of structures on a shaking table. Experimental physical and mechanical parameters of the polymers were determined, and similarity scales were calculated for models printed with the analysed polymers. The material parameters of the polymers determining the possibility and validity of their use in dynamic tests on a shaking table were also indicated.

6

Perspektywy rozwoju rozwiązań materiałowo-konstrukcyjnych belek zespolonych w świetle najnowszych badań

Nawrot Jacek

Przegląd Budowlany

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2023

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R. 94, nr 7-8

122--125

PL

Ciągły rozwój konstrukcji budowlanych powoduje doskonalenie istniejących oraz powstawanie nowych rozwiązań materiałowo-konstrukcyjnych, w tym również dotyczących belek zespolonych. W pracy dokonano przeglądu najnowszych badań w tym zakresie. Na ich podstawie wskazano, że największy potencjał rozwoju mają rozwiązania, których parametry wytrzymałościowe i użytkowe są porównywalne z tradycyjnymi konstrukcjami, bazujące na materiałach ekologicznych lub cechujących się niższą energochłonnością i emisyjnością niż stal czy beton, do produkcji których można wykorzystać odpady i surowce pochodzące z recyklingu.

EN

The continuous development of building structures results in the improvement of existing and the emergence of new material and structural solutions, including composite beams. The paper reviews the latest research in this field. On their basis, it was indicated that the greatest potential for development has solutions whose strength and performance parameters are comparable to traditional structures, based on ecological materials or characterized by lower energy consumption and emissivity than steel or concrete, for the production of which waste and recycled raw materials can be used.

7

Impact of orthodontic adhesive magnets on the mechanical properties and degree of conversion of a photopolymerized orthodontic adhesive

Al-Hayali Saud Khalil, Abed Mazin Ahmed, Al Qassar Sarmad Salih

Ochrona przed Korozją

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2023

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nr 10

329--334

EN

The purpose of this study was to calculate the effects of magnetic field (MF) on the degree of conversion (DC%) and mechanical properties of a photopolymerized orthodontic adhesive. In this investigation, Vega Ortho UV orthodontic adhesive was employed. The applied magnetic field had varying intensities (fixed at 0.01 T, 0.03 T, 0.05 T, 0.1 T, 0.15 T, and 0.2 T and a duration of 5 minutes) and a fixed frequency of 50 Hz. Vickers microhardness and DC% were investigated utilizing the specimens, which were created using circular molds and prepared for compression strength (CS) testing in accordance with ISO 4049. To evaluate DC% before and after MF exposure, Fourier-transform infrared spectroscopy (FTIR/ ATR) was performed. A microhardness tester was used to quantify the samples’ initial VHN while subjecting them to a 500 g load for 15 seconds. After that, properties were evaluated. With the aid of scanning electron microscopy (SEM), the surfaces were evaluated. The one-way analysis of difference and Tukey significant difference tests were used to evaluate the data. Analyses of statistical data showed that DC% tends to rise up to 0.05 T. When compared to the control, VHN and compression strength were considerably decreased after 0.03 T MF (p ≤ 0.05). However, there was a significant difference between the VHN and CS as their values increased with increasing magnetic field intensity. The surfaces of the Vega Ortho were deteriorated, as shown by SEM scans. It was found that the effect of the magnetic field caused changes in the physical and chemical properties.

PL

Celem badania było określenie wpływu pola magnetycznego (MF) na stopień konwersji (DC%) i właściwości mechaniczne fotopolimeryzowanego kleju ortodontycznego. W badaniu zastosowano klej ortodontyczny Vega Ortho UV. Zastosowane pole magnetyczne miało różne natężenia (0,01 T, 0,03 T, 0,05 T, 0,1 T, 0,15 T i 0,2 T przez 5 minut) i stałą częstotliwość 50 Hz. Mikrotwardość Vickersa i DC% ustalono z wykorzystaniem próbek, które zostały wykonane przy użyciu okrągłych form i przygotowane do badania wytrzymałości na ściskanie (CS) zgodnie z normą ISO 4049. Do oceny DC% przed ekspozycją na działanie pola magnetycznego i po niej wykorzystano spektroskopię w podczerwieni z transformacją Fouriera (FTIR/ATR). Do ilościowego określenia początkowej wartości VHN próbek użyto mikrotwardościomierza, poddając je obciążeniu 500 g przez 15 sekund. Następnie dokonano oceny właściwości. Ocenę powierzchni przeprowadzono za pomocą skaningowej mikroskopii elektronowej (SEM). Dane poddano jednokierunkowej analizie różnic i testowi istotnej różnicy Tukeya. Analizy danych statystycznych wykazały, że DC% ma tendencję do wzrostu do poziomu 0,05 T. W porównaniu z próbką kontrolną wartości VHN i wytrzymałości na ściskanie uległy znacznemu zmniejszeniu po oddziaływaniu 0,03 T MF (p ≤ 0,05). Istniała jednak znacząca różnica między VHN i CS, ponieważ ich wartości rosły wraz ze wzrostem natężenia pola magnetycznego. Powierzchnie Vega Ortho uległy degradacji, jak wykazały skany SEM. Stwierdzono, że wpływ pola magnetycznego spowodował zmiany właściwości fizykochemicznych.

8

The experimental study of the effect of magnetically sensitive elastomers on oil recovery of reservoirs containing high-viscosity oils

Mustafayeva Rena E.

Nafta-Gaz

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2023

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R. 79, nr 2

110--113

EN

In world practice, low-viscosity oil accounts for the main share of production. As the development progresses, the share of high-viscosity oil in the total balance increases year on year. The growing unused reserves of high-viscosity oil oblige researchers to solve the issue of developing these reserves, which is an important task for the oil industry. Studies have been carried out to increase oil recovery during the development of oil reservoirs containing high-viscosity oil by pumping a solution of magnetically active polymer, namely silicone oligomer, the matrix of which contains 5–25% Fe+3 ions, treated with a constant transverse magnetic field with a strength of H = 51740 A/m. A mixture of 90% by weight of quartz sand and 10% by weight of bentonite clay, with a permeability of k = 1.4 D, was used as a reservoir model. The high-viscosity oil model consisted of St-45 aviation oil. A silicone oligomer of 159–360 brand was used as a matrix with an operating temperature range of 60°C to +300°C, into which particles of gamma-Fe2O3 Nano powder with a size of 0.5 nm are introduced, with a degree of filling of the matrix of 5–25% by volume of Fe. Magnetization saturation is 80 emu/g, residual magnetization is 460 emu/g, and coercive force is 670 Oh. Validation of the proposed method was carried out by physical modeling of the process of displacement of high-viscosity oil with a magnetic elastomer on a laboratory installation. The oil recovery coefficient was calculated according to a wellknown method. The use of magnetically sensitive polymer can be an effective method of developing heavy oil fields. For each heavy oil field, taking into account its specifics (reservoir properties of the rock, physicochemical properties of oil, etc.), an appropriate magnet active polymer is selected. As the experimental results show, the best indicator of the oil recovery coefficient is achieved at 65%, compared with 48% of recovery in the absence of magnetic field exposure.

PL

W praktyce światowej główną część produkcji stanowią ropy o niskiej lepkości. W miarę postępu rozwoju udział rop o dużej lepkości w ogólnym bilansie rośnie z roku na rok. Rosnące niewykorzystane zasoby ropy naftowej o wysokiej lepkości obligują badaczy do rozwiązania kwestii zagospodarowania tych zasobów, co jest ważnym zadaniem dla przemysłu naftowego. W czasie zagospodarowania złóż ropy naftowej o dużej lepkości prowadzone były badania nad zwiększeniem wydobycia ropy poprzez tłoczenie roztworu magnetycznie aktywnego polimeru, jakim jest oligomer silikonowy, którego matryca zawiera 5–25% jonów Fe+3, poddanego działaniu stałego poprzecznego pola magnetycznego o natężeniu H = 51740 A/m. Jako model złoża zastosowano mieszaninę: 90% mas. piasku kwarcowego i 10% mas. glinki bentonitowej, o przepuszczalności k = 1,4 D. Modelem ropy o dużej lepkości był olej lotniczy St-45. Jako matrycę o zakresie temperatur pracy od 60°C do +300°C zastosowano oligomer silikonowy marki 159–360, do którego wprowadzone zostały cząsteczki nanoproszku gamma-Fe2O3 o rozmiarach 0,5 nm, a stopień wypełnienia matrycy jest w zakresie 5–25% obj. Fe. Nasycenie magnetyczne wynosi 80 emu/g, namagnesowanie szczątkowe wynosi 460 emu/g, a siła koercji wynosi 670 Oh. Walidację proponowanej metody przeprowadzono poprzez fizyczne modelowanie procesu wypierania oleju o dużej lepkości elastomerem magnetycznym w instalacji laboratoryjnej. Współczynnik odzysku oleju obliczono według znanej metody. Zastosowanie magnetycznie czułego polimeru może być skuteczną metodą zagospodarowania złóż ciężkich rop. Dla każdego złoża ciężkiej ropy naftowej, biorąc pod uwagę jego specyfikę (właściwości skały zbiornikowej, właściwości fizykochemiczne ropy itp.), dobierany jest odpowiedni polimer magnetycznie aktywny. Z eksperymentu wynika, że najlepszy współczynnik odzysku oleju osiągnięto na poziomie 65%, w porównaniu z 48% odzysku przy braku ekspozycji na pole magnetyczne.

9

A comprehensive review of polymer materials and selective laser sintering technology for 3D printing

Jabri F. E., Ouballouch A., Lasri L., Alaiji R. El

Journal of Achievements in Materials and Manufacturing Engineering

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2023

|

Vol. 118, nr 1

5--17

EN

Purpose: This review analyses different approaches used to study selective laser sintering (SLS) technology of polymer materials. These main approaches concern: thermal behaviour, fatigue and surface roughness. Design/methodology/approach: Regarding the first behaviour, researchers extensively studied the impact of process parameters, including scan speed, laser, power and laser energy density, on the thermal behaviour of 3D printed parts. Numerical and experimental analyses are used to conduct process parameter evaluations. Findings: Laser power and scan speed are the most significant parameters of the laser energy density. For the second, according to test protocols and quantitative analysis performed, the authors concluded that the combination of small and large laser energy density particles generates higher sintering and better fatigue resistance. Moreover, tensile analysis in different environments showed that testing in the water decreased the fatigue life of polymer samples. The influence of process parameters on the mechanical properties and surface roughness of 3D parts is also analysed. In addition, the investigators found that the additives increase the surface roughness of 3D printed parts. Practical implications: This review shows that researchers can focus on creating a combination of these approaches to expand the use of this process for industrial part production. Originality/value: All these investigations have made it possible to determine the optimal process conditions to ensure higher quality, optimal surface quality and better fatigue strength.

10

Mechanical analysis of multilayer composite materials with duroplastic matrix after exposure to low temperatures

Krzak Anna, Nowak A. J.

Archives of Materials Science and Engineering

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2023

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Vol. 122, nr 2

49--57

EN

Purpose: Cryogenic engineering is gaining more and more interest in various industry sectors, which leads to an intensive search for effective solutions. The article presents the findings of mechanical testing conducted on glass-epoxy laminates at room temperature and after long- term contact with liquid nitrogen. Design/methodology/approach: To compare the impact properties and flexural strength, the samples were tested under cryogenic and room conditions, and then the fracture locations were identified using the Leica DVM6 microscope. The study brings value to the emerging field of cryogenic engineering by providing valuable information on the mechanical properties of glass-epoxy composites under cryogenic conditions. Findings: It has been found out that immersing the glass-epoxy composites into the Dewar had minimal influence on impact and flexural strength properties. The most noticeable changes were observed in the case of the EP_4_2 composite. The material consists of a solution of brominated epoxy resin in an organic solvent. It is used to produce laminates in electrical engineering and printed circuits in electronics, where it should exhibit excellent impact properties. Research limitations/implications: One of the prospective research directions is a thorough analysis of the mechanical properties of the developed composite materials during cryogenic cycles. Originality/value: The study aims to determine the effect of different compositions of glass fabric-reinforced resin with a weight of 205 g/m2 on the mechanical properties of the developed composite materials at both room temperature and after long-term exposure to liquid nitrogen. Those investigations serve as surveillance for developing of new material solutions directed towards cryogenic applications and are essential for subsequent stages of research.

11

Investigation of the effect of polymer concentration in fracturing fluid on crack size and permeability during hydraulic fracturing

Moroz L. B., Uhrynovskyi A. V., Kogut G. M.

Archives of Materials Science and Engineering

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2023

|

Vol. 122, nr 2

70--77

EN

Purpose: This article aims to investigate the impact of polymer type and concentration in the fracturing fluid on the size and permeability of fractures during hydraulic fracturing. The aim is to predict the conductivity and productivity of the formed fractures in order to evaluate the cumulative gas production. Design/methodology/approach: The influence of polymer concentration in the fracturing fluid on the size and permeability of fractures was studied using the GOHFER software from Haliburton. Findings: The results of the study show that by combining the effect of increasing fracture size and decreasing the permeability of the proppant, a gas flow rate increase of 3.5 times was achieved. Research limitations/implications: High polymer concentrations lead to reduced permeability due to the accumulation of polymer residues and polymer skin. Practical implications: The conducted study on the impact of polymer concentration in the fracturing fluid on the size and permeability of fractures will allow for a more qualitative hydraulic fracturing process. Originality/value: This article presents how the concentration and type of polymer affect the width, thickness, length, and conductivity of fractures during hydraulic fracturing.

12

Leading-edge polymer/carbonaceous nano-reinforcement nanocomposites — opportunities for space sector

Kausar Ayesha, Ahmad Ishaq

Advances in Materials Science

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2023

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Vol. 23, nr 4(78)

99--122

EN

Carbonaceous or nanocarbon nano-reinforcement nanocomposites have been found as emergent candidates for aerospace industry. Consequently, the multifunctional nanocomposites have been fabricated using marvelous nanocarbon nanostructures like graphene, carbon nanotube, fullerene, carbon black, etc. Manufacturing techniques have also been engrossed for the formation of high performance engineering nanocomposites having fine strength, heat stability, flame resistance, and other space desired features. These practices include solution, in situ, and melt procedures, on top of specific space structural design techniques, for the formation of aerospace structures. The aerospace related material property enhancements using various carbonaceous nano-reinforcements depends upon the type of nanocarbon, dimensionality, as well as inherent features of these nanostructures (in addition to the choice of manufacturing methods). Furthermore, carbon nano-reinforcements have been filled, besides carbon fibers, in the epoxy matrices. Nanocarbon coated carbon fibers have been filled in epoxy resins to form the high performance nanomaterials for space structures. The engineering features of these materials have been experiential appropriate for the aerospace structures. Further research on these nanomaterials may be a key towards future opportunities in the aero systems. Additionally, the explorations on structure-property relationships of the carbonaceous nanocomposites have been found indispensable for the development of advanced aerospace structures.

13

Wpływ kąta rastrowania na właściwości mechaniczne polimeru PLA-IMPACT w technologii druku 3D

Boroń Paweł, Dulińska Joanna, Jurkowska Nadzieja, Tatara Tadeusz

Materiały Budowlane

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2022

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nr 4

6--10

PL

Celem pracy jest poznanie możliwości i uwarunkowań stosowania modeli wykonanych w technologii druku 3D do badań dynamicznych. Zaprezentowano metodę i wyniki badań określających parametry fizykomechaniczne polimeru PLA-IMPACT drukowanego z różnymi kątami rastrowania. Badania wykazały, że wartość modułu sprężystości polimeru nie zależy od kąta rastrowania, natomiast na granicę plastyczności ma wpływ kierunek laminacji, co wpływa w istotny sposób na realizację modeli obiektów do badań dynamicznych.

EN

The aim of the work is to identify the possibilities and conditions for the use of models made in 3D printing technology for dynamic experiments. The methodology and results of tests determining the physical and mechanical parameters of the PLA-IMPACT polymer printed with different screening angles are presented. The research showed that the value of the polymer modulus of elasticity does not depend on the rastering angle, while the yield point depends on the direction of lamination, which is of key importance in the implementation of models of objects for dynamic tests.

14

Roztwory polimerowe do zabezpieczania otworów pali i wykopów szczelinowych

Kłosiński Bolesław, Rychlewski Piotr

Materiały Budowlane

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2022

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nr 2

15--17

PL

Przedstawiono informacje o roztworach polimerowych do zabezpieczania otworów pali i szczelin, właściwości polimerów naturalnych i sztucznych, sposób ich działania, różnice w porównaniu z zawiesiną bentonitową. Opisano zasady stosowania roztworów polimerowych, sposób przygotowania, stężenie polimerów, sposoby kontroli roztworów, ich regeneracji i utylizacji oraz popełniane błędy. Zaletą stosowania polimerów jest łatwiejsze ich przygotowanie niż zawiesiny bentonitowej, mniejsze urządzenia, mniejsze zbiorniki, szybsza gotowość do użycia, a także czystość placu robót, łatwe oczyszczanie sekcji przed betonowaniem oraz łatwiejsza utylizacja zużytego roztworu. Konieczne jest jednak skontrolowanie całkowitego usunięcia osadu piasku i oczyszczenia dna otworu lub szczeliny przed zabetonowaniem. W artykule podano przykłady zastosowania polimerów w kraju.

EN

Information on polymer fluids for supporting pile boreholes and diaphragm excavations, properties of natural and artificial polymers, way of its performance, differences against bentonite slurries are presented. Rules of using of polymer fluids, their production, concentration of polymers, checking of their properties, regeneration, disposal and mistakes made sometimes are described. The advantages of the polymer fluids are easier production than of the bentonite slurry, smaller equipment and storage tanks, quicker making ready to use, and also clean working site, ease cleaning of a section before concreting and easier disposal of used up liquid. However, it is necessary to check a full removing of the sand sediment and cleaning up of the bottom of a borehole or excavation before concreting. Examples of polymer fluids application in Poland are given.

15

Pojedynek poliner hydro glass vs poliner hydro felt : porównanie wykładzin szklanych i filcowych do sieci ciśnieniowych

Kubera-Morka Agnieszka, Goździor Tomasz Michał

Inżynieria Bezwykopowa

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2022

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nr 2

58--64

PL

Jazda offroadowa wymaga auta specjalnie zaprojektowanego do tego celu. Podobnie wygląda sytuacja z doborem odpowiedniego materiału do renowacji. Specjalnie skonstruowana wykładzina ma w najlepszy sposób dopasować się do istniejącego wodociągu. Każdy offroad jest inny, ale przy dobrym doborze auta, kierowcy i pilota jesteśmy w stanie pokonać niemal dowolną trasę. Tak też jest z wykładzinami.

16

The role of lightweight materials in modern transport vehicles

Ćwiek Janusz, Wierzbicki Łukasz

Diagnostyka

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2022

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Vol. 23, No. 4

art. no. 2022405

EN

Polymeric materials and their composites in vehicles have experienced a real boom in the last 30 years, and their application is increasing with a tendency to further growth. The demands on the modern vehicle industry, whether they are trains, planes, or cars, are ever challenging - users want high-performance vehicles, but at the same time they are looking for improved reliability and safety, greater comfort, and low pricing. Changing the proportion of light-weight materials to steel in the construction of new vehicles helps make them lighter and more fuel or electrical energy efficient, resulting in lower greenhouse gas emissions. There is one family of materials that is responding to the challenge of these potentially conflicting demands: polymer materials. This includes relatively pure chemical materials as well as fibre-filled polymer composites.65 This article presents polymeric materials that are used for the production of vehicle parts today.

17

Performance of steel–polymer–steel seafloor pipeline buried in earthquake fault zones

Thang Vul, Hui David, Marshall Peter W., Zhou Jianren

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e174, 2022

EN

Steel tubular structures are widely used in offshore structures, such as fixed, floating, and seafloor pipelines. The earthquake can cause relatively large pipe displacement, especially in the fault zone. Therefore, single-wall buried pipelines or piles of the offshore fixed platform in these zones could be under buckling and wrinkling which would lead to the severely deteriorated performance of the pipelines or costly failure. The purpose of this research is to prevent these types of failures by developing innovative double-wall steel–polymer–steel (SPS) composite pipes in place of single-wall pipes. In the double-wall pipe, the annulus of the inner and outer pipe was grouted with polymer. Verification exercises for single-wall pipe in air and buried in clay, and double-wall pipes in the air were performed. Thereafter, an analysis of laterally loaded SPS double-wall composite pipes in clay was performed and the pipe responses were examined. A comparison of performance behaviors for single and double-wall pipes was also performed. It was found from this research that double-wall SPS composite pipes demonstrated increased tolerance for higher levels of displacements, strain, stress, and ovality under work environments where pipelines could be subjected to large displacement in the earthquake fault zone. For those composite pipes in which there is no bond between the polymer layer and inner/outer steel pipes, the composite pipes showed wrinkles on the compression side of the pipe even under a small displacement. So, the polymer and steel must be bonded to have a good composite section. The composite pipes with stiffer polymer grout showed a better performance while soft polymer did not contribute to the overall stiffness of the composite pipes. In addition, the effects of weld on the outer steel pipes were also studied and the results were documented.

18

Investigation of joining mechanism of electrical-assist friction stir joining between polyethylene (PE) and 316 stainless steel

Derazkola Hamed Aghajani, Kordani Naser, Abokheili Rasool Mohammadi

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e199, 2022

EN

In this study, the Polyethylene (PE) polymer and 316 stainless steel textiles lap welded by the electrical-assist friction stir joining (EA-FSJ) technique. Effects of stirring action of tool and electrical current heat on joining mechanism between PE sheets and 316 stainless steel are investigated. A scanning electron microscope (SEM) was used to investigate of internal material flow. To study the bonding mechanism in joint line, Fourier-transform infrared spectroscopy (FT-IR) and energy-dispersive X-ray spectroscopy (EDS) techniques were employed. Differential scanning calorimetry (DSC) was used to analyze of PE structure after welding. The results show that the joining mechanism in this joint consists of chemical bonding and mechanical locking between 316 stainless steel and PE. The presence of extra heat by electrical current decreased the strength of steel during the welding process and consequently increased chemical bonding and mechanical joining. The final joint flexural and tensile strength were increased by 9 and 10%, respectively, comparing PE raw sheet. The electrical heat increases the PE softening front of the tool and decreases joint thinning after the welding procedure. The mixing between PE and 316 stainless steel fragments increases the stir zone hardness near 84 ShoreD.

19

Interpreting the experimental results of compressive strength of hand-mixed cement-grouted sands using various mathematical approaches

Mahmood Wael, Mohammed Ahmed Salih, Sihag Parveen, Asteris Panagiotis G., Ahmed Hawreen

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 1

art. no. e19, 2022

EN

Using two different test standards (ASTM and BS), the influence of five different sizes of sand on the ultimate stress (MPa) of hand-mixed cement-grouted sands modified with polymer is discussed in this study. The characteristics of cement-grouted sands modified with polymer up to 0.16% (percent weight of dry cement) were evaluated and measured in fresh and hardened conditions. Adding polymer decreased the water/cement ratio (w/c) from 0.6 to 0.5, and it kept the flow time of the cement-based grout in the range of 18 to 23 s recommended by ASTM standard. Using mix proportion and curing time, adding polymer significantly increased the prismatic and cylindrical compressive strength (MPa) by 113 to 577% and 53 to 459%. Several mathematical approaches such as linear regression (LR), Nonlinear regression (NLR), multilinear regression (MLR), Artificial neural network (ANN), and M5P-tree were used to predict the compression strength of cement-grouted sand with a different size of sand, w/c, polymer content, and curing age. Based on the scatter index (SI), objective function (OBJ) assessments, and training and testing datasets, the compressive strength of the cement-grouted sands can be predicted well using NLR and ANN models. The compression strength tested using the BS standard was 71% higher than the compression strength of the same mix tested using the ASTM standard.

20

Wpływ działania plazmy niskotemperaturowej na zmiany zwilżalności wybranych polimerów

Hołysz Lucyna, Kamela (Rymuszka) Diana, Terpiłowski Konrad, Chibowski Emil

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1270--1295

EN

The effects of air, oxygen and argon plasma treatment on wetting and energetic properties of polymers: polymethylmethacrylate (PMMA), polyetheretherketone (PEEK), polyoxymethylene (POM), polyamide (PA6G), polycarbonate (PC) and polypropylene (PP) were studied. The changes in surface properties of PMMA, PEEK, POM, PA6G polymers after the air plasma treatment, and PP and PC polymers after the Ar or O2 plasma treatment were determined via the measurement of advancing and receding contact angles of three liquids having different polarity, i.e. water, formamide and diiodomethane. Having the determined contact angles the surface free energy and its components of the polymers were calculated using three different theoretical approaches, namely: acid-base Lifsthitz-van der Waals (LWAB), contact angle hysteresis (CAH) and Owens and Wendt (O-W). The effects of plasma treatment were further determined by calculations of the adhesion work and work of spreading of water on modified polymer and compared to values calculated for the unmodified surfaces. Then for the PEEK and POM modified with the air plasma, their surface wettability was determined after 14 days from the exposure to the plasma. It was found that plasma treatment caused better wettability what reflected in a decreased contact angles measured on the modified polymer surfaces. The greatest changes appeared for polar liquids, i.e. water and formamide. It pointed to an increased the surface hydrophilicity after the plasma treatment. The changes correlated also with the increased polar interactions due to appearance polar groups on the surface. For the studied polymer surfaces, generally the dispersive interactions practically did not change, regardless the treatment time and plasma type. The total surface free energy values calculated for the polymers from three different approaches to interfacial interactions are similar. However, the energy values are apparent because they depend s upon the kind of liquid used for the contact angles measurement. Irrespectively of the plasma type, for all polymers an increase of the adhesion work of water in reference to the unmodified surfaces was observed. The most appropriate time to improve the adhesion between the polymer surface and liquid was found to be 25 or 60 s. However, the effects of plasma treatment are not permanent. With the storage time the contact angles have increased. This can be due to the structure reorganization within a few nm thick the surface layer.