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1

Wpływ powłok Cr, Ti, Cr/Ti na właściwości tribologiczne stali X38CrMo16

Drabik Szymon, Madej Monika, Piotrowska Katarzyna, Radoń-Kobus Krystyna

Obróbka Metalu

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2024

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nr 1

40--47

PL

W artykule przedstawiono badania dotyczące wpływu powłok Cr, Ti, Cr/Ti na właściwości tribologiczne stali X38CrMo16 stosowanej, m.in. do wytwarzania form wtryskowych. Powłoki uzyskano techniką fizycznego osadzania z fazy gazowej PVD. Zwilżalność powierzchni określono za pomocą tensjometru optycznego przy użyciu metody kropli siedzącej. Testy tribologiczne przeprowadzono za pomocą tribometru TRB3 w skojarzeniu trącym kula-tarcza w ruchu posuwisto-zwrotnym w warunkach tarcia technicznie suchego. Przeciwpróbkę w badanych węzłach tarcia stanowiła kulka ze stali 100Cr6. Po testach tarciowo-zużyciowych próbki poddano obserwacjom mikroskopowym. Wartości kątów zwilżania wodą demineralizowaną wskazały, że wszystkie badane powierzchnie charakteryzują się dobrą zwilżalnością. Na podstawie uzyskanych wyników badań tribologicznych stwierdzono, że powłoki charakteryzowały się mniejszymi oporami ruchu oraz zużyciem w porównaniu do stali X38CrMo16, przy czym najmniejsze wartości uzyskano dla powłoki Cr.

EN

In this paper the influence of Cr, Ti, Cr/Ti coatings on tribological properties of X38CrMo16 steel used, among others, for the production of injection molds were examined. The coatings were obtained by the PVD gas phase physical deposition technique. The wettability of the surface was determined by an optical strain gauge using the sedentary drop method. Tribological tests were performed with the TRB3 tribometer in reciprocating ball-disc friction combination under technically dry friction conditions . The counter-sample in the friction nodes tested was a 100Cr6 steel ball. After the friction and wear tests, the samples were subjected to microscopic observations. The values of the wetting angles with demineralized water indicated that all tested surfaces are characterized by good wettability. Based on the resuIts of tribological tests, it was found that the coatings were characterized by Iower resistance to movement and wear with respect to X38CrMo16 steel, with the lowest values obtained for the coating Cr.

2

Analysis of the effect of assembly joints technology on the strength of adhesive joints of poly(methyl methacrylate) (pmma) used in advertising elements

Rudawska Anna, Penkała Piotr, Miszczuk Bartosz, Stančeková Dana

Technologia i Automatyzacja Montażu

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2023

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nr 2

3--10

EN

The aim of the article was to present issues related to the influence of the assembly joints technology (the type of adhesive material and the adhesive application) on the strength of the adhesive joints of poly(methyl methacrylate) (PMMA) used in the production of advertising elements. Angular adhesive joints, which are one of the types of joints made in the construction of advertising elements, were used in the study. The bonded material was poly(methyl methacrylate) (PMMA) of 8 mm thick. Two types of adhesives were used to make the adhesive joints: one-component solvent-based adhesives and methylene chloride as a solvent. Experimental tests determined the wettability of the surface of the adherends (with and without a protective coating) and the work of adhesion based on the measurement of the contact angle, as well as the strength of adhesive joints in accordance with the ISO 4578 standard. Based on the results of strength tests, it can be seen that the use of a solvent allows for obtaining equally strong joints as with the use of solvent-based adhesives. The purposefulness of using coatings protecting not only against dirt or mechanical damage in the form of scratches was also confirmed, but also the possibility of increasing (security) adhesive properties, defined in this case by wettability.

PL

Celem artykułu było przedstawienie zagadnień związanych z wpływem technologii połączeń montażowych (rodzaju materiału klejącego i sposobu aplikacji kleju) na wytrzymałość połączeń klejowych z poli(metakrylanu metylu) (PMMA) stosowanych w produkcji elementów reklamowych. W badaniach wykorzystano połączenia klejowe kątowe, które są jednym z rodzajów połączeń wykonywanych w konstrukcji elementów reklamowych. Łączonym materiałem był poli(metakrylan metylu) (PMMA) o grubości 8 mm. Do wykonania połączeń klejowych zastosowano dwa rodzaje jednoskładnikowych klejów rozpuszczalnikowych oraz chlorek metylenu, jako rozpuszczalnik. W badaniach doświadczalnych określono zwilżalność powierzchni klejonych elementów (z powłoką ochronną i bez) oraz pracę adhezyjną na podstawie pomiaru kąta zwilżania, a także wytrzymałość połączeń klejowych zgodnie z normą ISO 4578. Na podstawie wyników badań wytrzymałościowych można stwierdzić, że zastosowanie rozpuszczalnika pozwala na uzyskanie połączeń równie wytrzymałych, jak przy zastosowaniu klejów rozpuszczalnikowych. Potwierdzono również celowość stosowania powłok zabezpieczających nie tylko przed zabrudzeniami czy uszkodzeniami mechanicznymi w postaci zarysowań, ale także w celu zwiększenia (zabezpieczenia) właściwości adhezyjnych, określanych w tym przypadku przez zwilżalność.

3

Analiza wpływu zwilżalności ośrodka skalnego na parametry termiczne na podstawie profilowań geofizycznych i danych laboratoryjnych

Lis-Śledziona Anita, Słota-Valim Małgorzata, Stadtmüller Marek

Nafta-Gaz

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2023

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R. 79, nr 4

227--243

PL

Celem prowadzonych badań była analiza i oszacowanie wpływu systemu zwilżalności ośrodka skalnego na jego parametry termiczne. W zależności od temperatury, składu mineralnego, porowatości i nasycenia wodą skałę charakteryzuje określona przewodność cieplna. Jednak nie tylko ilość wody w formacji wpływa na przewodność cieplną. Ważne jest także rozmieszczenie wody w skale, które w znacznym stopniu determinowane jest przez zwilżalność. Woda w skałach wodozwilżalnych pokrywa ziarna i tworzy tzw. film wodny na powierzchni minerałów, wypełnia także małe pory skały, tworząc strugi, ścieżki perkolacji dla migracji fazy przewodzącej ciepło (wody), ale też przewodzącej prąd elektryczny. W skałach hydrofobowych film wodny na powierzchni ziaren mineralnych jest nieciągły lub w ogóle go brak, gdyż większa część powierzchni skały pokryta jest ropą, natomiast woda w większości wypełnia centralną część porów o dużych średnicach. W pracy wykazano, że istnieje zależność pomiędzy systemem zwilżalności skały a przewodnością termiczną oraz przeprowadzono modelowanie ilościowe. Analizowano dane literaturowe z badań na hydrofilowych i hydrofobowych próbkach piasku przy różnym stopniu nasycenia wodą. Obserwacja eksperymentu prowadzącego do zmiany charakteru zwilżalności skały z hydrofilowej na hydrofobową na drodze powleczenia ziaren piasku polimerem zainspirowała autorów niniejszej pracy do zaproponowania dwóch równań przedstawiających zależność przewodności termicznej (λ) od współczynnika nasycenia wodą (Sw) dla skał wodozwilżalnych i skał ropozwilżalnych. W skałach wodozwilżalnych zaobserwowano wykładniczy wzrost przewodności cieplnej wraz ze wzrostem współczynnika nasycenia wodą, natomiast w skałach ropozwilżalnych zależność λ od Sw przedstawiono przy wykorzystaniu funkcji logistycznej. W ramach testowania modeli wykonano serię obliczeń dla czterech hipotetycznych skał klastycznych i czterech skał węglanowych. Przeprowadzono analizę wyników i obliczono przewodność termiczną w rzeczywistym ośrodku skalnym, wykształconym w postaci piaszczysto-ilastych utworów paleozoicznych, dla którego istniały opracowane wcześniej przez autorów wyniki interpretacji parametrów litologiczno-złożowych. Jednym z takich parametrów była obliczona i skalibrowana z wynikami badań laboratoryjnych krzywa zwilżalności. Stanowiła ona podstawę do podziału interpretowanego interwału na strefy wodozwilżane i ropozwilżalne. Ostatecznym wynikiem pracy jest estymacja zakresów zmienności przewodności cieplnej analizowanych skał w funkcji zwilżalności oraz parametrów petrofizycznych (zailenie Vcl, porowatość efektywna PHI, współczynnik nasycenia wodą Sw).

EN

The study aimed to evaluate the impact of the rock medium's wettability system on the thermal properties of the rock. The rock exhibits a specific thermal conductivity depending on the temperature conditions, mineral composition, porosity, and water saturation. However, it is not only the amount of water in the rock that affects its thermal conductivity. The water distribution in the rock, which is mostly determined by its wettability, is also essential. Water in the water-wet rocks covers the grains and creates a so-called water film on the minerals' surfaces. It also fills the tiny pores of the rock, creating streams and percolation paths for the migration of the heat-conducting and electrically conductive phases. In hydrophobic rocks, the water film on the surfaces of the minerals grains is discontinuous or non-existent as most of the rock surface is covered with oil, while water fills the central part of the pores of larger diameters. The results of the study confirmed the existence of a relationship between the rock wettability system and thermal conductivity based on the quantitative modeling that was carried out. The data from the literature were analyzed and tested by taking the hydrophilic and hydrophobic sand samples at various degrees of water saturation. The results of the experiment found in the literature leading to a change in the characteristics of the sand samples from initially hydrophilic into hydrophobic by coating sand grains with thermosensitive polymer led to an idea of proposing two equations presenting the dependence of thermal conductivity on the water saturation coefficient for water-wet and oil-wet rocks. In water-wet rocks, an exponential increase in thermal conductivity was observed with an increase in the water saturation coefficient. In contrast, in oil-wet rocks, the dependence of thermal conductivity λ on Sw was expressed using a logistic function. As part of model testing, a series of calculations were carried out for four hypothetical clastic rocks and four carbonate rocks. The analysis of the obtained results allowed to calculate thermal conductivity for real clastic rock medium represented by Paleozoic sandy claystone formation, with previously developed by the authors lithological interpretation and 1D models of reservoir properties. Among these parameters, a wettability curve was calculated and calibrated with the laboratory data. The wettability was used to distinguish interpreted intervals into the water- and oil-wet zones. Finally, as a result, the variability ranges of thermal conductivity of analyzed rocks were estimated as a function of wettability and petrophysical parameters (Vcl clay volume, PHI effective porosity, Sw water saturation).

4

The wettability of nitrogen and argon implanted WC-Co indexable knives used for wood-based material machining

Barlak Marek, Wilkowski Jacek, Werner Zbigniew, Podziewski Piotr

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2023

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No. 122

27--35

EN

The wettability of nitrogen and argon implanted WC-Co indexable knives used for wood-based material machining. An attempt was made to examine the effect of the depth profiles of the implanted ions on the wettability of ion implanted WC-Co tools used for wood-based material machining. The tests were carried for two types of the tool surfaces, i.e. initial and polished, two commonly used gases, i.e. nitrogen and argon, and for the values of the parameters, possible to control in the case of classic ion implanters. Four depth profiles were modelled for two different values of the acceleration voltage, two for each implanted element. The modelling parameters were selected so that the two modelled depth profiles for both implanted elements were similar. The wettability tests were carried using a computer-supported test stand. The obtained results did not confirm the hypothesis about the relationship between the wettability and the position and the shape of the depth profiles.

PL

Zwilżalność implantowanych azotem i argonem narzędzi WC-Co, wykorzystywanych w obróbce materiałów drewnopochodnych. Podjęto próbę sprawdzenia wpływu profili głębokości implantowanych jonów na zwilżalność implantowanych jonowo narzędzi WC-Co, stosowanych do obróbki materiałów drzewnych. Badania przeprowadzono dla dwóch rodzajów powierzchni narzędzi, tj. wyjściowej i polerowanej, dwóch powszechnie stosowanych gazów, tj. azotu i argonu oraz dla wartości parametrów możliwych do uzyskania w przypadku klasycznych implantatorów jonów. Zamodelowano cztery głębokościowe profile dla dwóch różnych wartości napięcia przyspieszającego, po dwa dla każdego implantowanego pierwiastka. Parametry modelowania dobrano tak, aby dwa modelowane profile głębokości dla obu implantowanych pierwiastków były podobne. Badania zwilżalności były prowadzone na wspomaganym komputerowo stanowisku testowym. Uzyskane wyniki nie potwierdzają hipotezy o zależności między zwilżalnością a położeniem i kształtem głębokościowych profili implantowanych pierwiastków.

5

Ocena wybranych właściwości mechanicznych i fizycznych akrylowych cementów kostnych o niskiej lepkości

Zając Zuzanna, Łagan Sylwia, Liber-Kneć Aneta

Aktualne Problemy Biomechaniki

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2023

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z. 23

35--42

EN

The aim of this work was comparison mechanical and physical properties of bone cements used in human and animal orthopedics. The mechanical properties were determined by compression tests, a contact angle was observed with a goniometer and the surface free energy was calculated by Owens-Wendt model. Two states of material (initial and after incubation) were considered. The incubation process changed the nature of the surface to hydrophilic and caused an increase in the polar component of the surface free energy. The obtained compression curves are similar, showing both linear and plastic regions, with an conventional yield point.

PL

Celem pracy było porównanie właściwości mechanicznych i fizycznych powierzchni cementów kostnych stosowanych w ortopedii. Właściwości mechaniczne określono za pomocą statycznej próby jednoosiowego ściskania, kąt zwilżania wyznaczano przy użyciu goniometru optycznego, a swobodną energię powierzchniową obliczono według modelu Owensa-Wendta. Rozpatrzono dwa stany materiału (początkowy i po inkubacji). Proces inkubacji zmienił charakter powierzchni na hydrofilowy i spowodował wzrost wartości składowej polarnej swobodnej energii powierzchniowej. Otrzymane krzywe ściskania dla badanych stanów są podobne, ukazując obszar liniowy, jak i plastyczny, z umowną granicą plastyczności.

6

Surface free energy and roughness of flowable dental composites

Łagan Sylwia, Chojnacka-Brożek Agnieszka, Liber-Kneć Aneta, Malik Gabriela

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 3

EN

The surface properties like roughness, wettability and surface free energy are important for utility properties of traditional and flowable dental restorative composites, due to their role in plaque formation, discoloration, mechanical wear or adhesion and bonding. The goal of our work was to assess the surface free energy (SFE) and the surface roughness (Ra) of three commercial flowable dental composites: everX Flow (bulk), everX Flow (dentin) and Flow-Art. Methods: Surface roughness, contact angle and surface free energy were determined for tested composites. Two surface states (control and roughened) were compared. Roughness was measured with the use of the 3D optical profilometer. The contact angle (CA) was determined through the sessile drop method with the use of four different probing liquids. This enabled to apply two surface free energy approaches (Owens–Wendt (O-W) and van Oss– Chaudhury–Good (LWAB)). Additionally, Zisman’s approach (γC) was used. Results: The water contact angle values were similar for Flow-Art (67.56±1.49°) and everX Flow (bulk) (68.94±2.72°) compared to higher value for everX Flow (dentin) (74.39±2.05°). SFE was in the range from 43 to 50 mJ/m2 for O-W and from to 62 mJ/m2 for LWAB. The γC was from 37 47 to 45 mJ/m2 . Conclusions: Roughening composites’ surface influenced on increasing the CA value. All approaches of surface free energy calculations provide useful data for predicting interactions between flowable composites and dental tissues. Tested composites showed good wetting for initial state of surface after polymerization. These influence on better adhesion of the material to the bonding system during dental restoration.

7

Multiscale water drop contact angles at selected silica surfaces

Zhang Chen, Wang Xuming, Li Lixia, Jin Jiaqi, Polson Randy, Miller Jan D.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 152154

EN

In this study, multiscale advancing contact angles for glycerol/water drops at silica surfaces are reported for millidrops, submicron-drops, and nanodrops. Selected silica surfaces were muscovite, silicon, and talc. The contact angles for millidrops (1–2 mm) were determined by the traditional sessile drop technique. For submicron-drops (0.1–1.0 μm), a hollow tip Atomic Force Microscope (AFM) procedure was used. The contact angles for nanodrops (~7 nm) were examined from Molecular Dynamics (MD) simulation. The results were compared to evaluate the effect of drop size on the contact angle. In the case of the hydrophobic talc surface, the 75° advancing contact angle did not vary significantly with drop size. For the hydrophilic muscovite surface, the water drop wet the surface and an advancing contact angle of about 10° was found for the millidrops and submicron-drops. However, for the MD simulated nanodrops, attachment and spreading of the ~7 nm drop created a 2D film of molecular dimensions, the contact angle of which was difficult to define and varied from 0° to 17°. Perhaps of equal interest from the MD simulation results was that the spreading of the glycerol/water nanodrop at the muscovite surface resulted in crystallographic directional transport of water molecules to the extremities of the 2D film. Such separation and segregation left the center of the film with an increased concentration of glycerol. Based on these results, the line tension, which has been found in other investigations to account for contact angle decrease with a decrease in drop size, does not seem to be a significant factor in this study.

8

Studies on water transport in quasi two-dimensional porous systems using neutron radiography

Fijał-Kirejczyk Izabela M., Rogante Massimo, Milczarek Jacek J., Żołądek-Nowak Joanna, Jurkowski Zdzisław, Żołądek Jan, Rusinek Dariusz

Nukleonika

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2022

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Vol. 67, No. 1

3--9

EN

The spontaneous wetting and drying of flat porous samples of linen, cotton and synthetic textiles were studied using dynamic neutron radiography (DNR). The progress of the wetting process of the media was delineated from the obtained neutron dynamical radiography images. The results of the investigation reveal a non-classical behaviour of kinetics of wicking of these materials. The character of the wetting kinetics is discussed in terms of the fractal character of the tortuosity of fabric capillaries.

9

Microstructure and surface free energy of light-cured dental composites after their modification with liquid rubber

Sowa Monika, Przekora Agata, Pałka Krzysztof

Engineering of Biomaterials

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2022

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vol. 25, no. 164

9--15

EN

The use of liquid rubber as a component of light-cured dental composites is one of the methods of increasing their fracture toughness. It also reduces polymerization shrinkage and offers the potential to lower water sorption. The aim of the study was to evaluate the miscibility of liquid rubber in composite matrix resins as well as changes in the wettability and surface free energy (SFE) values of commercial lightcuring composites after their modification with liquid rubber. The research materials were Flow Art and Boston (Arkona) light-cured composites and resin mixtures used in their production. Liquid rubber Hypro 2000X168LC VTB (Huntsman Int.) was used as a modifier. The solubility of liquid rubber was assessed under light microscopy. The contact angle and SFE measurements were made on a DSA30 goniometer (Kruss) using water and diiodomethane. It was found that the liquid rubber solubility depended mainly on the viscosity of the resin, which was related to the amount of BisGMA. The resulting mixture showed good temporal stability without larger domains. The curing process released the liquid rubber as a separate phase formed as spherical domains. The morphology of these domains was homogeneous and their size did not exceed 50 µm in diameter. The presence of liquid rubber in modified composites increased their hydrophobicity and reduced the surface free energy value. The obtained properties might help to reduce the formation of bacterial biofilm on dental fillings.

10

Biological and mechanical research of titanium implants covered with bactericidal coating

Malisz Klaudia, Świeczko-Żurek Beata

Engineering of Biomaterials

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2022

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vol. 25, no. 165

17--22

EN

Materials used in bone implants should not only be non- -toxic to the surrounding tissues, but also should promote osseointegration and minimize the risk of infection. Infections are a serious problem contributing to implantation failure. They are associated with pain, immobilization, and the necessity of reoperation. In extreme cases, they can lead to significant inflammatory changes in the bones, which, in turn, can lead to amputation and even death. After implantation, the surrounding tissues are damaged. In addition, implants are susceptible to bacterial colonization due to the lack of microcirculation. Therefore, scientists are working on antibacterial coatings to prevent the adhesion of bacteria before tissue regeneration. The paper concerns the biological and mechanical properties of titanium implants with an antibacterial coating. The Ti13Zr13Nb alloy samples were coated with hydroxyapatite (HAp) coatings using the electrophoretic deposition technique (EPD). Subsequently, the surface of the samples was modified with silver, copper, and nickel nanoparticles by the immersion method. Different titanium sample types (i.e. HAp-only and nanometals-enriched coatings) were placed in a bacterial solution for a period of one month. Each sample was examined using scanning electron microscopy (SEM), nanoindentation, nanoscratch, and contact angle tests. The significant amount of dead biofilm on the surface proves the effectiveness of antibacterial activity. The wettability assessment showed that the samples were hydrophilic. The conducted tests of mechanical properties indicate the heterogeneity of the coatings.

11

Relative wettability measurement of porous diffuser and its impact on the generated bubble size

Al-Yaqoobi Atheer M.G., Zimmerman William B.

Chemical and Process Engineering

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2022

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Vol. 43, nr 1

45-–55

EN

Controlling the bubble size is a major concern in enhancing transport performance in gas-liquid systems. The role of wettability of diffuser surface on bubble size is the subject of the current work. The study inspects the contact angle of a set of liquids on HP ceramic diffusers using the Washburn method. The results demonstrate that organic liquids like toluene, methanol–water (1:1 v/v), ethanol– water (1:1 v/v) and decane have small contact angles of 12.9, 37.5, 24.4 and 22.5 respectively. Water has a lower wettability than the organic compounds where the contact angle was about 67.4. The effect of wettability of the bubble size is investigated by measuring the size of air bubble produced using the same diffuser material. The results of bubble size measurement demonstrates that with liquids of small contact angle, i.e. good wetting properties, small bubble sizes are produced in comparison with liquids with a higher contact angle. The study demonstrates the viability of Washburn method in characterization of wettability of porous diffuser, which was verified by measuring the bubble size produced. A high reduction in bubble size can be obtained by a carefully chosen diffuser material that provides better wettability.

12

Experimental Investigation of the Wettability of Protective Glove Materials: A Biomimetic Perspective

Irzmańska Emilia, Jastrzębska Aleksandra, Kaczmarek Łukasz, Adamus-Włodarczyk Agnieszka

Autex Research Journal

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2022

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Vol. 22, no. 4

427--437

EN

The objective of the present work was to evaluate the surface wettability of commercially available polymeric protective gloves, as well as to determine the effects of their surface topography in conjunction with the glove material on the hydrophobic properties of the final products, together with surface free energy (SFE) and work of adhesion. The geometric structures imparted to the surface led to different levels of hydrophobicity and SFE. Most of the studied materials were characterized by good wettability properties. It was shown that a textured surface topography affects wettability. The highest SFE was found for nitrile butadiene rubber materials. All materials except for nitrile butadiene rubber exhibited good hydrophobic properties and relatively low work of adhesion.

13

Wettability of the System of Cast Iron and Magnesia Ceramics with Graphite

Hosadyna-Kondracka Małgorzata, Nowak Rafał, Turalska Patrycja, Bruzda Grzegorz, Boroń Łukasz, Wawrylak Marek

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 3

25--33

EN

In this paper examinations of high-temperature wetting tests of 3 systems of liquid alloy – cast iron in contact with ceramic materials: magnesia ceramics in combination with natural graphite were presented. After wettability testing, the microscopic observations of the morphology of the sample surface and the cross-section microstructure with the chemical composition in micro-areas were examined. One of the objective of this work was also to verify whether the graphite content would affect the wettability of the magnesia ceramics. The study of high-temperature wetting kinetics of the liquid alloy in contact with the ceramic material, by the "sessile drop" method with capillary purification (CP) procedure was conducted. Under the test conditions, at a temperature of 1450°C and time 15 minutes, all 3 experimental systems showed a non-wetting behaviour. The average contact angle for the system with cast iron drop on magnesia ceramics was 140°, on magnesia ceramics with 10 parts per weight of graphite was 137° and on magnesia ceramics with 30 parts per weight of graphite - 139°. Microscopic observations revealed that in the case of the sample consisting of the cast iron drop on the substrate with magnesia ceramics, the formation of fine separations was not observed, unlike the systems with the substrate with magnesia ceramics and the addition of natural graphite. Numerous, fine droplets accumulate on the graphite flakes and consist mainly of Si as well as Fe and O. On the other hand, the rough MgO grains have a gray, matt surface, without fine separations. The conducted observations indicate the mechanical nature of the bonding - liquid metal penetrates into the pores of the rough ceramics of the substrate. However, in the case of systems of cast iron drop with magnesia ceramics and addition of graphite, probably the adhesive connection and the physical attraction of elements derived from cast iron drop with the flake graphite appeared as well.

14

Wettability of the surface of bacterial cellulose film modified with the ion implantation

Betlej Izabela, Barlak Marek, Wilkowski Jacek, Werner Zbigniew, Zagórski Jerzy, Lipska Karolina, Boruszewski Piotr

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2022

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No. 118

15--21

EN

Wettability of the surface of bacterial cellulose film modified with low energy ion implantation The paper presents the preliminary results of the modification on the water wettability of cellulose, using ion implantation method. Two kinds ions of the noble gases, i.e. helium and argon were implanted with fluences of 1e15 nand 1e16 cm-2, and with the ion energy of 60 keV. The measurements of the contact angle values show the different influence of both types ions on the hydrophobicity of the modified cellulose, but the hydrophobicity of implanted cellulose increases in all cases. The real investigations were supplemented with the modelling results of the depth profiles of the implanted ions and the main parameters of the modelled peaks.

PL

Zwilżalność powierzchni celulozy bakteryjnej modyfikowanej metodą implantacji jonów. Artykuł przedstawia wstępne wyniki modyfikacji na zwilżalność wodą implantowanej jonami celulozy. W badaniach wykorzystano dwa rodzaje gazów szlachetnych, tj. hel i argon. Implantowane dawki wynosiły 1e15 i 1e16 cm-2, a energia jonów 60 keV. Pomiary kąta zwilżania pokazują różny wpływ obydwu typów jonów na hydrofobowość modyfikowanej celulozy, jednakże hydrofobowość wzrasta we wszystkich przypadkach. Badania zostały uzupełnione wynikami modelowania głębokosciowych profili implantowanych jonów i głównych parametrów modelowanych pików.

15

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.

16

Characteristic of polypropylene nanocomposite material reinforcement with hydroxyapatite for bone replacement

Obaid M. N., Sabr O. H., Hussein A. A.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 104, nr 1

21--30

EN

Purpose: Human bone suffered some degeneration due to age and accidents; therefore, there are many interests in the prepared synthetic bone with properties nearer to natural bone. The present study prepared a nanocomposite of polypropylene reinforced with different weight fraction of Nano hydroxyapatite (HAp) to be used as a bone replacement with good biological properties that enhanced the growth of osteoplastic cells and enhance the prevention of clots and coagulates creation. Design/methodology/approach: Nanocomposite from polypropylene reinforced with different weight fraction of Hydroxyapatite (HAp) (1,2 and 3) % prepared by first dispersion Nano hydroxyapatite insolvent and then mixing with a pellet of polypropylene by the twin-screw extrusion process, the current research study the surface properties ( atomic force microscopy (AFM), contact angle test) Moreover, it studied the characteristics of prepared nanocomposite materials (Differential Scanning Calorimetry (DSC), Field Emission-Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared (FTIR)). Findings: The AFM results show the surface roughness decreased with increasing content of HAp, which diminished the chance of creation clots and coagulates on it. The contact angle results referred to polypropylene behaviour transformed from hydrophobic to hydrophilic with addition HAp that permission to grow the osteoplastic cell on it, so the healing process is accelerated. Moreover, the FE-SEM images revealed uniform distribution and good bonding between polypropylene and Hydroxyapatite. The thermal properties were measured by the DSC test showed the melting temperature, and the enthalpy of melting (indicated to increase the crystalline structure per cent) are increased with increasing the percentage of Hydroxyapatite. Research limitations/implications: This research studied the characteristics of nanocomposite materials prepared by three steps (dispersion by ultrasonic device, manually mixed and melting and mixing by twin extruder) which can be used as a bone replacement. However, the main limitation was the uniform distribution of nano-hydroxyapatite within the matrix. In a further study, the cytotoxic test can be tested to study the effect of prepared nanocomposite on living cells’ growth. Practical implications: The interest object is how to connect among different properties to prepared bone replacement with good properties and biocompatibility that made able to stimulate the growth and healing process. Originality/value: The nano-hydroxyapatite is a biomaterial that has a composition similar to the natural mineral phase of the bone and does not have any negative effect, which enhanced the growth of osteoplastic cells and decreased the clots and coagulates creation; therefore, nano-hydroxyapatite is used to decrease the surface roughness which decreased the chance of coagulation creation and to enhance the hydrophilic properties.

17

Surface roughness and wettability performance of thermally modified rowan wood as a fast-growing species

Candan Zeki, Görgün Hızır Volkan, Korkut Süleyman, Ünsal Öner

Drewno : prace naukowe, doniesienia, komunikaty

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2021

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vol. 64, nr 208

35--44

EN

This study aims to examine the effect of the thermal modification process on the surface roughness properties of the wood of rowan (Sorbus aucuparia L.) as a fast-growing species. Four thermal modification processes were applied, with temperatures of 160 and 180°C and durations of 2 and 4 hours. In total five groups were compared, including the untreated group. Arithmetical mean roughness, maximum height, ten-spot average roughness, and root-mean-square deviation were measured using a stylus-type profilometer, both parallel and perpendicular to the grain, according to the JIS B 0601 standard. Wettability was determined by measuring the contact angle of a droplet of distilled water. After dripping, the camera captured several images to measure the contact angle. The results showed that thermal modification decreases the wettability of the samples. Moreover, increments in temperature and duration may further decrease wettability. On the other hand, there are no significant differences between groups in terms of the surface roughness values, measured both parallel and perpendicular to the grain, except for two groups. It is concluded that these process conditions did not substantially change the surface roughness properties of rowan wood panels. However, the decrease in wettability may provide new possibilities for the use of less-known wood species.

18

Hydrophilization of Polyester Textiles by Nonthermal Plasma

Azeem Musaddaq, Javed Asif, Morikawa Hideaki, Noman Muhammad Tayyab, Khan Muhammad Qamar, Shahid Muhammad, Wiener Jakub

Autex Research Journal

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2021

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Vol. 21, no. 2

142--149

EN

Polyester is a popular class of material used in material engineering. With its 0.4% moisture regain, polyethylene terephthalate (PET) is classified as highly hydrophobic, which originates from its lack of polar groups on its backbone. This study used a parallel-plate nonthermal plasma dielectric barrier discharge system operating at medium pressure in dry air and nitrogen (N2) to alter the surface properties of PET fabrics to increase their hydrophilic capabilities. Water contact angle, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) were utilized to analyze any effect from the plasma treatment. The wettability analysis revealed a reduction in the contact angle of more than 80% within 5 min for both discharges. Scanning electron microscopy analysis showed no microscopic damage to the fiber structure, guaranteeing that the fabrics’ structural integrity was preserved after treatment. AFM analysis showed an increase in the nanometer roughness, which was considered beneficial because it increased the total surface area, further increasing the hydrophilic capacity. XPS analysis revealed a sharp increase in the presence of polar functional groups, indicating that the induced surface changes are mostly chemical in nature. Comparing that of untreated fabrics to treated fabrics, a Increase in water absorption capacity was observed for air-treated and N2-treated fabrics, when these fabrics were used immediately after plasma exposure.

19

Synthesis of a magnetic ionic liquid ([C12mim]FeCl4) and its interactions with low-rank coal

Li Zhihao, Liu Mingpu, Lin Mengyu, Ma Chuandong, He Meng, Wang Qingbiao, Yu Hao, Li Lin, You Xiaofang

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 3

566--578

EN

he large number of oxygen-containing functional groups present on the surface of low-grade coal contribute to its strong hydrophilic properties and rendering coal beneficiation by flotation challenging. In this study, a magnetic ionic liquid (IL), [C12mim]FeCl4, was developed as a green medium to treat low-rank coal. Notably, the IL can be recovered using a magnetic field. The interactions between the low-rank coal and the IL were analyzed, and the structure and properties of [C12mim]FeCl4 were characterized using Raman spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, and vibrating-sample magnetometry. Moreover, the effects of the newly prepared IL on the wetting properties of low-rank coal were studied using water contact angle measurements. The contact angle of the coal sample treated with the IL increased initially but decreased with subsequent increase in treatment time, indicating a change in coal wettability with time. The results from FT-IR analysis show that the changes in contact angles may be attributed to the changes to the oxygen-containing functional groups at the coal surface upon interaction with the IL, where the content of oxygen-containing functional groups in the treated coal sample initially decreased but subsequently increased with increase in treatment time. X-ray photoelectron spectroscopy analysis confirmed these results. Thus, it can be concluded that [C12mim]FeCl4 initially destroys the oxygen-containing functional groups at the coal surface, resulting in an increase in the water-coal contact angle but subsequently promoting oxidation of the coal surface, hence causing a reduction in the contact angle.

20

Fabrication of transparent polysiloxane coatings on a glass support via the sol-gel dip coating technique and the effect of their hydrophobization with hexamethyldisilazane

Chodkowski Michał, Terpiłowski Konrad, Pasieczna-Patkowska Sylwia

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 6

76--88

EN

This study aimed at synthesis, preparation, and physicochemical properties investigation of undoped polysiloxane-based coatings deposited on the glass supports. The other goal was to test the effectiveness of their hydrophobization with hexamethyldisilazane at an elevated temperature using a bubbler. The coatings were obtained in a sol-gel process by acid-assisted hydrolysis of tetraethoxysilane and they were applied to the glass supports using the dip coating technique with various withdrawal speeds. The synthesized composition was scanned using TurbiscanLAB and its particle size was determined by means of the dynamic light scattering technique. The obtained surfaces were examined based on the water wettability measurements, photoacoustic spectroscopy, and transmittance measurements. It was found that the stability of the sol did not change during the dip-coating. Smooth, homogeneous, uniform, hydrophobic, and transparent coatings on the glass supports were obtained. Their wettability was determined by the contact angle in the range from 83.5 to 95.2 degrees and very low contact angle hysteresis. The hydrophobic effect obtained by modification with hexamethyldisilazane appears to be permanent – the contact angles do not change significantly after 7 days. The synthesized sol composition appears to be a good starting point for its chemical and physical modification for hydrophobicity increase and surface properties modification. Moreover, the hydrophobization of the coatings with hexamethyldisilazane at an elevated temperature using the bubbler did not have the desired effect.