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1

Evaluation of Surface Preparation Technology for Steel Components with Fluoropolymer-based Coatings in Terms of Anti-adhesive and Mechanical Properties

Miturska-Barańska Izabela, Doluk Elżbieta

Advances in Science and Technology. Research Journal

|

2023

|

Vol. 17, no 6

140--154

EN

The subject of the research presented in this paper was the evaluation of the technology of surface preparation of steel samples in terms of anti-adhesion and mechanical properties through the use of PFA coatings. Such coatings are used in many industries, e.g. in the manufacture and operation of metal moulds used, for example, in the production of resinous components. The specimens used in the study, which represented the surface of the moulds, were made from DC01 sheet. Six variants of release coating technology were used, differing in the number of technological operations and parameters. In the final stage, appropriate test methods were used to assess the energy properties of the coatings produced, the mechanical properties in terms of deformation of the supporting structure and the mechanical properties in terms of the effects on the coating itself. The scope of the research made it possible to determine the main properties that the manufactured coatings have in terms of their future practical applications. The results obtained for the surface free energy determined from the measurement of the surface wetting angle, the mechanical properties obtained from the three-point bending test and the evaluation of the surface quality of the coatings subjected to compressive and tensile deformations in the bending test, as well as the functional properties of the coatings in terms of their durability and adhesion determined in scratch tests, showed that the best characteristics were obtained for variant 6. This variant consisted of sequentially, after the initial stage, applying a primer layer and drying it for 15 minutes at 250°C, applying a PFA layer to the component at 150°C and then drying it for 15 minutes at 200°C and curing it for 20 minutes at 380°C. An additional layer of PFA was then applied and dried for 15 minutes at 200°C and cured for 20 minutes at 340°C. In addition, a long annealing for 3 hours at 340°C was applied in a given variant.

2

Surface free energy and roughness of flowable dental composites

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

Acta of Bioengineering and Biomechanics

|

2023

|

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.

3

Electrokinetic and surface properties of some methacrylate-based copolymers

Ersoy Bahri, Çiftçi Hakan, Evcin Atilla, Merdivenci Yılmaz

Physicochemical Problems of Mineral Processing

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2022

|

Vol. 58, iss. 5

art. no. 152162

EN

In this study, some electrokinetic and surface properties of MBAOM-GMA copolymers synthesized from 2-[(methoxy-1,3-benzothiazole-2-yl) amino]-2oxoethyl methacrylate (MBAOM) and glycidyl methacrylate (GMA) monomers were investigated. Accordingly, (i) pH-dependent zeta (ζ) potential changes of the copolymers were investigated under a constant ionic strength (in 1.10-3mol/dm3 NaCl) and the corresponding isoelectric points (iep) were determined, (ii) zeta potential changes depending on the salt concentration in the presence of mono-, di- and tri-valent metal salts were examined, (iii) contact angles (θ) of the copolymers with water were measured and their wetting behavior was assessed, and (iv) surface free energies (SFE) of the copolymers were determined by Acid-Base approach using Van Oss-Chaudhury-Good method. The compositions of the copolymers were 77% MBAOM - 23% GMA, 45% MBAOM - 55% GMA, and 19% MBAOM - 81% GMA. FeCl3, CaCl2, and KCl salts were used for the salt solutions for the zeta potential measurements. As a result, (i) it was determined that the chemical structure of methacrylate copolymers showed a decisive effect on both electrokinetic and surface properties, (ii) the hydrophobic character of copolymer increased with the increase of the GMA ratio, and correspondingly, the SFE decreased, and (iii) the iep of the copolymers varied between pH 3.1-3.7 depending on composition.

4

Control of glass surface wettability via esterification with n-alkyl alcohols

Kruszelnicki Mateusz, Polowczyk Izabela, Kowalczuk Przemyslaw B.

Physicochemical Problems of Mineral Processing

|

2022

|

Vol. 58, iss. 2

art. no. 145147

EN

Surface wettability plays an essential role in many processes and materials applications. It depends mainly on the surface roughness and chemical composition, thus through a controlled modification of these parameters, the wettability can be restrained. Glass is an inorganic solid material, composed mainly of amorphous silica, which surface, due to the presence of reactive hydroxyl groups, can be quite easily chemically modified. This feature can be used to control the wettability of glass by reaction with organic compounds. In this study, the esterification of glass silanol groups with n-alkyl alcohols (Cn/H2n+1/OH, n=3, 4, 6, 8, 10) was employed to modify its wettability. The effect of such modification on the physicochemical properties of glass surface was comprehensively investigated and characterised by the water contact angle, surface free energy, zeta potential, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) measurements. We demonstrate that the wettability of the esterified glass surface is strongly dependent on both the chain length of used alcohol and modification time. The alcohol molecule binds to the glass surface through a Si-O-C bond, leading to the formation of a monolayer that does not significantly affect the surface morphology and zeta potential. Conducted studies provided a broader view of the influence of this technique for modifying surface wettability on its physicochemical properties.

5

Application of the Ozonation Process for Shaping the Energy Properties of the Surface Layer of Polymer Construction Materials

Kłonica Mariusz

Journal of Ecological Engineering

|

2022

|

Vol. 23, nr 2

212--219

EN

The properties of the surface layer of construction materials are very important for making adhesive bonds. The article presents the test results for surface free energy in PA6 polyamide subjected to surface layer modification using the ozonation process. To develop the surface geometrically, the samples were subjected to mechanical processing. The comparison of results demonstrated that ozonation is an efficient and eco-friendly method of modifying the surface layer. The article also presents the comparison results for measurements of selected surface roughness parameters.

6

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

|

2022

|

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.

7

Effect of Face Milling Parameters of Carbon Fiber Reinforced Plastics Composites on Surface Properties

Miturska-Barańska Izabela, Józwik Jerzy, Bere Paul

Advances in Science and Technology. Research Journal

|

2022

|

Vol. 16, no 2

26--38

EN

This paper analyses the influence of face milling process parameters on the surface properties of carbon fibre reinforced polymer. The influence of milling speed and feed per tooth on the surface properties was determined. The influence of cutting speed and feed per tooth on surface energy properties was determined. The object of research was a carbon fiber reinforced plastics (CFRP) composites plate made of carbon fibre in epoxy matrix. The tool used in the study was a double-edged end mill. The machining parameters used were variable: cutting speeds of 100 m·min-1, 120 m·min-1, 140 m·min-1 and 160 m·min-1, and feeds per tooth of 0.015 mm/tooth, 0.020 mm/tooth, 0.025 mm/tooth and 0.03 mm/tooth. The axial depth of cut and radial depth of cut was a constant parameter. After milling, tests were carried out on the surface contact angle, which was used to determine the surface free energy. Based on the contact angle measurements carried out with the sitting-drop method and the calculation of the surface free energy with the Owens-Wendt model, it was observed, that the increase in the value of the surface free energy is significantly influenced by the increase in the cutting speed.

8

Wpływ działania plazmy niskotemperaturowej na zmiany zwilżalności wybranych polimerów

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

Wiadomości Chemiczne

|

2021

|

[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.

9

Influence of the Biocidal Agent Layer on Selected Properties of the Blown Polyethylene Film

Jachowicz Tomasz, Kłonica Mariusz, Majewski Łukasz

Advances in Science and Technology. Research Journal

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2020

|

Vol. 14, no 4

315--325

EN

This paper discusses the problems connected with applying a biocidal substance onto the surface of a blown extruded polyethylene film in order to improve the functional properties of the film while maintaining its processing properties unchanged. The objective of the study was to determine the relationship between biocide application method and selected properties of the tube film. Two methods of biocide application onto the film surface were developed: one relied on spraying the biocide onto the hot melt surface directly during the extrusion process, while in the other the biocide was sprayed horizontally onto the blown film after the extrusion process. Biocide distribution uniformity, friction coefficients and surface free energy of the modified film were examined, and the quality and mechanical strength of heat- sealed joints were estimated. In addition, the geometric properties of the blown film were determined.

10

Wettability of quartz particles at varying conditions on the basis of the measurement of relative wetting contact angles and their flotation behaviour

Gao Shuling, Ma Lifeng, Wei Dezhou, Shen Yanbai

Physicochemical Problems of Mineral Processing

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2019

|

Vol. 55, iss. 1

278--289

EN

In this paper, on the basis of a modified Washburn equation, the squared incremental pressure due to liquid rising vs. time were measured instead of wicking distances before reaching equilibrium, and the relative wetting contact angles (RWCA) were applied to characterize the surface wettability of quartz particles conditioned at different concentrations of flotation reagents. Combined with the flotation experiments on quartz particles at corresponding conditions, the relationship between flotation recoveries and RWCA was analysed, which proves that RWCA can characterize the surface wettability of quartz particles accurately. The results also showed that the best reagent conditions for floating quartz are pH 12.0, a Ca2+ concentration of 1×10-3 mol/dm3 and a sodium oleate concentration of 0.75×10-3 mol/dm3, where the recovery of quartz is 86%. The surface tension of the filtrate of the pulp was determined by a fully-automatic tensiometer as well. Based on the measured values of RWCA and surface tension, the free energy changes (ΔG) before and after the adhesion of bubbles and particles per unit area at corresponding situations were calculated, respectively. The trends of ΔG varying with the concentrations of reagents were in close accordance with those of RWCA and the flotation recoveries, proving that it is more likely for particles having bigger contact angles to adhere to bubbles, resulting in a higher flotation recovery. These results give a more feasible and accurate approach to analysing the surface wettability and floatability of fine particles.

11

Surface free energy of extruded polymer compositions

Garbacz Tomasz

Physicochemical Problems of Mineral Processing

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2019

|

Vol. 55, iss. 6

1509--1516

EN

Suitable adhesive properties of the polymer compositions provide largely outer surface of the product. The aim of the studies was evaluation of the efficiency of the extrusion process and physical properties of PVC modified by selected auxiliary. In the studies PVC was used. PVC was modified by blowing agent (0-1.5% by mass) and antistatic agent (0-0.8% by mass) in the form of polyvinyl chloride concentrates. Efficiency of extrusion process is determined also by selected proprieties of surface layer of a mill cake of polyvinyl chloride. Surface free energy has been calculated in Owens-Wendt method. Antistatic agent causes diminishing of wettability and adsorption of surface layer and eventually increase of surface free energy of surface layer. For ensuring appropriate adhesion properties of a surface layer it would be advisable to use, for polyvinyl chloride modification, the antistatic agent in the amount not smaller than 0.4% by mass in relation to polyvinyl chloride mass. Taking into account research results, which can be useful during the development of processing technology of the polyvinyl chloride used for polymers composites, it can be stated that the content of the blowing agent used, noticeably decreasing polymer mass and simultaneously not worsening the properties of a surface layer, should not exceed 0.5÷1.0% by mass in relation to polyvinyl chloride mass.

12

The Influence of Surface Free Energy on Tribological Properties of Oxide Layers Formed on Aluminium Alloy EN AW-5251

Niedźwiedź M., Bara M., Skoneczny W.

Tribologia

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2018

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nr 4

71--79

EN

This paper presents the influence of the parameters of the formation of oxide layers on the surface free energy and the tribological properties of these layers. The layers were formed electrochemically on aluminium alloy EN AW-5251, with variable values of electrolyte temperature and current density. A three-component electrolyte was used to produce oxide layers. The surface free energy was determined by the droplet deposition method by measuring the wetting angles, while the van Oss-Chaunhury-Good method was used for the calculations. Tribological tests were performed on a T-17 tribological tester under conditions of technically dry friction for reciprocating motion. T7W composite was used as a specimen in tribological tests.

PL

W artykule przedstawiono wpływ parametrów wytwarzania warstw tlenkowych na swobodną energię powierzchniową oraz właściwości tribologiczne tych warstw. Warstwy zostały wytworzone na stopie aluminium EN AW-5251 metodą elektrochemiczną, przy zmiennych wartościach temperatury elektrolitu oraz gęstości prądowej. Do wytwarzania warstw tlenkowych zastosowano elektrolit trójskładnikowy. Swobodna energia powierzchniowa wyznaczona została metodą osadzonej kropli poprzez pomiar kątów zwilżania, natomiast do obliczeń zastosowano metodę van Ossa-Chaunhury’ego-Gooda. Testy tribologiczne przeprowadzono na testerze tribologicznym T-17 w warunkach tarcia technicznie suchego dla ruchu posuwisto-zwrotnego. W testach tribologicznych jako próbki użyto kompozytu T7W.

13

Problems of Tribologic Characterization of Shoe – Walking Surface Friction Pairs

Przepiórka J., Szczerek M.

Tribologia

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2018

|

nr 6

125--129

EN

Tribological characteristics of shoe sole in a friction pair with the walking surface are important parameters due to the safety of shoe exploitation and time of its durability. The footwear industry methods of analysing friction coefficient are obsolete, and, on the other hand, modern tribological equipment that allows credible results requires long data processing. The authors suggest using a previously developed formula that binds tribological characteristics with energetic condition of the walking surface. By doing so, this formula evaluates the force of friction and wear of shoe – walking surface pair. It may shorten the time needed to evaluate the basic parameters of shoe exploitation in variable conditions of their utilization and, thus, contribute to the formulation of material resolutions aiming to improve the quality of shoe usage while reducing the costs of performing required examinations.

PL

Charakterystyki tribologiczne podeszew obuwia w skojarzeniu z podłożem są parametrami istotnymi z punktu widzenia bezpieczeństwa jego użytkowania oraz czasu eksploatacji. Metody badania współczynnika tarcia i zużycia stosowane w przemyśle obuwniczym są przestarzałe, natomiast nowoczesne urządzenia tribologiczne pozwalające na otrzymywanie wiarygodnych wyników badań wymagają długich, wielogodzinnych biegów badawczych. Autorzy sugerują wykorzystanie reguły wiążącej charakterystyki tribologiczne z energetycznym stanem powierzchni trących do określania wielkości siły tarcia i zużycia skojarzenia podeszwy obuwniczej z podłożem. Może to pozwolić na skrócenie czasu potrzebnego do określenia podstawowych parametrów eksploatacyjnych obuwia w zmiennych warunkach eksploatacji, przyczyniając się do opracowywania rozwiązań materiałowych ukierunkowanych na poprawę jakości obuwia przy znaczącej redukcji niezbędnych do tego kosztów badań.

14

Wpływ promieniowania rentgenowskiego na stabilność wybranych właściwości polietylenu

Wiśniewska A., Chwalik G., Łagan S.

Inżynieria Powierzchni

|

2018

|

nr 1

3--11

PL

Przeprowadzono ocenę procesu degradacji polietylenu (PE) w warunkach in vitro pod wpływem działania promieniowania rentgenowskiego (X) oraz inkubacji w dwóch roztworach symulujących środowisko żywego organizmu (SBF – simulated body fluid). W badaniach wykorzystano dawkę odpowiadającą 10 standardowym zdjęciom rentgenowskim układu kostnego oraz roztwory Ringera i soli fizjologicznej o temperaturze 40°C. Przedstawiono wyniki wpływu 12-miesięcznych badań na wybrane właściwości powierzchni materiału: zwilżalności powierzchni oraz ścieralności. Na podstawie pomiarów kąta zwilżania określono wartość swobodnej energii powierzchniowej (SEP). Wykonano również analizę przewodności płynów inkubacyjnych. Otrzymane wyniki wskazują, że przyjęta dawka promieniowania rentgenowskiego nie ma istotnego wpływu na zwilżalność powierzchni polietylenu. Charakter warstwy wierzchniej polietylenu nie zmienił się na skutek 12-miesięcznej inkubacji i pozostał hydrofilowy. Dla próbek inkubowanych w obu płynach imersyjnych zaobserwowano spadek wartości swobodnej energii powierzchniowej (SEP). Zarówno dla napromieniowanego materiału, jak i grupy kontrolnej nie stwierdzono znaczących zmian w masie próbek oraz przewodności płynów inkubacyjnych, co wskazuje na stabilność polietylenu. Uzyskano natomiast wzrost wartości ścieralności o ok. 26%. Wraz z upływem czasu inkubacji zauważono spadek wartości tego parametru dla polietylenu poddanego działaniu promieniowania. Dla grupy kontrolnej nie stwierdzono znaczących zmian.

EN

The evaluation of a degradation process of polyethylene (PE) in in vitro conditions under the influence of X-rays (X) and an in-cubation in two solutions simulating the environment of a living organism (SBF – simulated body fluid) was carried out. A dose corresponding to 10 standard X-ray pictures of the skeletal system as well as Ringer's and saline solutions at 40°C were used in the study. The paper presents the results of the influence of the 12-month studies on the selected surface properties of the material: surface wettability and abrasiveness. The value of surface free energy (SFE) was determined on the basis of the wetting angle measurements. The conductivity of the incubation fluids was also analyzed. The obtained results indicate that the adopted dose of X-ray radiation has no significant effect on the wettability of the surface of polyethylene. The nature of the surface layer of polyethylene did not change as a result of the 12-month incubation and remained hydrophilic. For the samples incubated in both immersion fluids, a decrease in surface free energy (SFE) was observed. For both the irradiated material and the control group, no significant changes in the mass of the samples and the conductivity of the incubation fluids were found, which indicates the stability of polyethylene. However, the abrasion value increased by approximately 26%. With the passage of the incubation time, a decrease in the value of this parameter was observed for the polyethylene subjected to radiation. No significant changes were found for the control group.

15

Ocena właściwości elastomerów wykorzystywanych na smoczki dziecięce w badaniach przyspieszonego starzenia

Żelasko A., Mrowiec A., Światłoń M., Niedziela E., Walaszczyk M., Zielińska E., Łagan S.

Aktualne Problemy Biomechaniki

|

2018

|

z. 15

67--74

PL

Celem pracy była ocena wpływu procesu przyspieszonego starzenia materiałów wykorzystywanych do produkcji smoczków dziecięcych, na zmianę właściwości powierzchni na podstawie pomiarów kąta zwilżania. Wyznaczona swobodna energia powierzchniowa (SEP) oraz jej składowe wskazują na wyraźny wpływ parametrów procesu starzenia na właściwości powierzchni smoczków lateksowych i silikonowych. Badania ujawniły znaczące różnice w kierunkach zmian SEP na skutek zjawiska starzenia. Uważa się, iż ma to wpływ na inicjowanie zjawiska adhezji bakterii.

EN

The aim of the study was to assess the impact of the accelerated aging of materials for baby’s pacifiers, on the surface properties based on wetting measurements. The research method consisted in assessing the contact angle in the sitting drop procedure based on the analysis of its shape in the subsequent stages of the aging process. For each stage and material, the value of surface free energy (SEP) was determined, which was also subjected to statistical analysis. Analytical model of Owens-Wendt was used for the calculations.

16

The Effect of Active Diluent Addition on the Energy and Adhesive Properties of Epoxy Adhesive

Krawczuk Anna, Domińczuk Jacek

Advances in Science and Technology. Research Journal

|

2018

|

Vol. 12, no 1

19--25

EN

The paper reports values of surface free energy and its components of an epoxy adhesive modified by the addition of an active diluent. Wetting envelopes are determined and they serve as a basis for a wettability analysis and determining the possibility of maximizing the work of adhesion between the liquid and the solid. Static strength tests of adhesive joints made with the analysed adhesive compositions were also conducted. The results are used to determine the effect of active diluent addition on the energy and adhesive properties of the epoxy adhesive

17

Analiza właściwości energetycznych kompozycji klejowych dedykowanych do połączeń klejowo-zgrzewanych

Krawczuk A., Domińczuk J.

Technologia i Automatyzacja Montażu

|

2017

|

nr 2

61--65

PL

W pracy przedstawiono wyniki badań swobodnej energii powierzchniowej kompozycji klejowych, utworzonych w celu zapewnienia właściwych warunków wypełniania szczelin w połączeniach hybrydowych, takich jak połączenie klejowo-zgrzewane. Przedstawiona w pracy analiza wartości składowych polarnej i niepolarnej dla badanych klejów posłużyła do określenia zdolności kleju do zwilżania powierzchni. Podstawą do określenia wartości składowych swobodnej energii powierzchniowej były pomiary kąta zwilżania przez wybrane substancje adhezyjne na materiale o znanym stanie energetycznym warstwy wierzchniej. W oparciu o przeprowadzoną analizę możliwe było sklasyfikowanie kompozycji wg ich właściwości energetycznych, sprzyjających procesowi zwilżania powierzchni łączonych materiałów.

EN

The paper presents the results of measurements of surface free energy for adhesive compositions created in order to provide the appropriate conditions for filling gaps in the hybrid joints, such as weld-bonded joints. Presented in the paper analysis of polar and non-polar components of surface free energy for the studied adhesives was used to determine the ability of the adhesive to wet the surface. The basis for determining the value of surface free energy were measurements of the contact angle by selected adhesive substances on the material with a specific energy state of the surface layer. Based on this analysis, it was possible to classify the composition according to the energy properties conducive to the process of wetting the surface of the joined materials.

18

Surface free energy of composite materials with high calcium carbonate filler content

Rudawska A., Jakubowska P., Kloziński A.

Polimery

|

2017

|

T. 62, nr 6

434--440

EN

The adhesive properties of ternary composites based on middle density polyethylene (PE-MD) and isotactic polypropylene (i-PP) with high content (48–64 wt %) of inorganic fillers were studied. As fillers two kinds of calcium carbonate were used. Two fillers differed in their fineness degree and one of them had also stearic acid modified surface. It was stated that the kind and amount of filler affect mean value and scatter of surface free energy (γS) as well as its polar and dispersive components. More stable adhesive properties were observed for composites with stearic acid modified filler.

PL

Zbadano właściwości adhezyjne trójskładnikowego kompozytu na bazie polietylenu średniej gęstości (PE-MD) i izotaktycznego polipropylenu (i-PP) z wysoką zawartością (48–64 % mas.) nieorganicznych napełniaczy. Jako napełniaczy użyto dwu rodzajów węglanu wapnia, które różniły się stopniem rozdrobnienia, a ponadto ten o drobniejszych cząstkach miał powierzchnię modyfikowaną kwasem stearynowym. Stwierdzono, że rodzaj i ilość napełniacza wpływają na rozrzut i wartość średnią swobodnej energii powierzchniowej (γS) oraz jej komponentów: polarnego i dyspersyjnego. Bardziej stabilne właściwości adhezyjne zaobserwowano w grupie kompozytów z napełniaczem modyfikowanym kwasem stearynowym.

19

Polytetrafluoroethylene thin films obtained by the pulsed electron beam deposition method at different gas pressures

Jędrzejewski R., Piwowarczyk J., Kwiatkowski K., Baranowska J.

Polimery

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2017

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T. 62, nr 10

743--749

EN

Polytetrafluoroethylene (PTFE) coatings were manufactured using the pulsed electron beam deposition (PED) technique. The presence of a PTFE structure was confirmed by means of Fourier transform infrared spectrometry (FT-IR). The surface morphology and roughness were characterized by atomic force microscopy (AFM). A pressure increase leads to a decrease in the material transport from the target to the substrate. The water contact angle (WCA) and surface free energy (SFE) were examined. The hydrophobic properties were preserved after film deposition.

PL

Cienkie powłoki z politetrafluoroetylenu (PTFE) wytwarzano metodą pulsacyjnej ablacji elektronowej (PED) z zastosowaniem zmiennego ciśnienia gazu roboczego. Techniką spektroskopii w podczerwieni z transformacją Fouriera (FT-IR) potwierdzono strukturę chemiczną osadzonej cienkiej warstwy. Za pomocą mikroskopii sił atomowych (AFM) oceniano morfologię i chropowatość otrzymanej powierzchni. Wyznaczono kąt zwilżania (WCA) i swobodną energię powierzchniową (SFE) powłok z PTFE. Stwierdzono, że zachowują one hydrofobowe właściwości politetrafluoroetylenu. Zwiększenie wartości zastosowanego w procesie ciśnienia wpłynęło na zmniejszenie grubości osadzanej warstwy PTFE w wyniku pogorszenia transportu materiału z targetu (tarczy) do podłoża.

20

Influence of dry grinding on physicochemical and surface properties of talc

Arsoy Z., Ersoy B., Evcin A., Icduygu M. G.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

288--306

EN

In this study the effect of dry grinding on hydrophobicity, surface free energy (SFE), particle size distribution, surface area, porosity, oil absorption, and whiteness of talc was investigated. The dry grinding was performed in a vibrating ball mill at various grinding times (5-150 min) by keeping the grinding parameters constant such as the number of ball, ball size, the amount of talc, vibration frequency and amplitude. Then, the contact angle measurements were performed on disc-shaped samples produced under a hydraulic press by using a sessile drop method with different liquids (water, formamide, diiodomethane, and ethylene glycol), and surface free energies (mJ/m2) were calculated according to OCG-AB (van Oss-Chaudhury-Good Acid-Base) method by using the obtained contact angle values. In addition, the physicochemical analyses given above were carried out for each ground sample. According to the obtained results, the water contact angle and SFE of the original sample were 63.800 and 48.70 mJ/m2, respectively. The lowest and highest contact angle values for the samples were obtained as 59.300 and 70.770 at grinding times for 5 and 15 min, respectively. It was also determined that the grinding time over 30 min showed no significant effect on the contact angle and SFE values of the samples. Similarly, the grinding time vs. SFE, and the grinding time vs. contact angle curves showed a similar trend. Parallel to the increase in the surface area upon the grinding, a small increase in the oil absorption and whiteness of talc was also determined.