The Measurement of Surface Energy by Video Analysis of Captive-Bubble Contact-Angles

1995 ◽  
Vol 75 (3) ◽  
pp. 763-766 ◽  
Author(s):  
Jeremy C. Thomas ◽  
John Davenport
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Video Analysis ◽  
Sea Water ◽  
Contact Angles ◽  
Marine Organisms ◽  
Surface Energies ◽  
Cyanea Capillata ◽  
Ptfe Sheet ◽  
Non Destructive

Surface energy has been demonstrated to have a significant effect upon the settlement and growth of many marine organisms. However, the measurement of surface energy has either been too expensive for most marine laboratories to consider its use, or the methods used have relied upon classical contact-angle theory. Modern contact-angle theory and a video-based technique using captive bubbles are described. The technique is non-destructive, inexpensive, rapid and accurate enough to compare living and man-made surfaces. A precision of ~5° has been achieved and rapidly-changing angles can be quantified. Data for PTFE sheet, Parafilm, acetate sheet, Geltek gel, sea-water-conditioned slate, Porphyra umbilicalis (L.) Agardh, Ciona intestinalis (L.), and Cyanea capillata (L.) are presented. The contact angles for the living surfaces are smaller (31–44°) than for all the non-living surfaces (73–112°), suggesting overall higher surface energies for the biological materials studied.

scholarly journals On the limitations of the applicability of Young’s equations temperature

2021 ◽  
Vol 23 (2) ◽  
pp. 218-222
Author(s):  
Magomed Pashevich Dokhov
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Interfacial Energy ◽  
Contact Angles ◽  
Surface Phenomena ◽  
Surface Energies ◽  
Three Phase ◽  
Production Techniques ◽  
The Difference ◽  
Solid Liquid

The article uses the thermodynamics of interfacial phenomena to justify the fact that Young’s equations can correctly describe the three-phase equilibrium with any type of interatomic bonds. Wetting, adhesion, dissolution, surface adsorption, and other surface phenomena are important characteristics, whichlargely determine the quality and durability of materials, and the development of a number of production techniques, including welding, soldering, baking of metallic and non-metallic powders, etc. Therefore, it is important to study them.Using experimental data regarding surface energies of liquids (melts) and contact angles available in the literature, we calculated the surface energies of many solid metals, oxides, carbides, and other inorganic and organic materials without taking into account the amount of the interfacial energy at the solid-liquid (melt) interface. Some researchers assumed that in case of an acute contact angle the interfacial energy is low. Therefore, they neglected it and assumed it to be zero.Others knew that this value could not be measured, that is why they measured and calculated the difference between the surface energy of a solid and the interfacial energy of a solid and a liquid (melt), which is equal to the product of the surface energy of this liquid by the cosine of the contact angle. It is obvious that these methods of determining the surface energy based on such oversimplified assumptions result in poor accuracy.Through the use of examples this paper shows how the surface energies of solids were previously calculated and how the shortcomings of previous calculations can be corrected

scholarly journals Free Energy Balance of Polyamide, Polyester and Polypropylene Surfaces

2012 ◽  
Vol 7 (4) ◽  
pp. 155892501200700 ◽  
Author(s):  
Marcela Bachurová ◽  
Jakub Wiener
Keyword(s):  
Contact Angle ◽  
Free Energy ◽  
Energy Balance ◽  
Surface Energy ◽  
Solid Surface ◽  
Contact Angles ◽  
Surface Energies ◽  
Receding Contact ◽  
Smooth Plate

The wettability of a solid surface is often characterized by the contact angle of liquid on the solid surface. The wettability is pertinent to surface energy, which is an important parameter. The wettability can be affected, for example, by the roughness of the solid surface. In our work textiles are used as macroscopic roughness surfaces, and smooth plate surfaces are used as well to determine surface energies. For the calculation of surface energies it is fundamental to know the contact angle. The advancing and receding contact angles are measured, and the relation between the hysteresis and surface energy is monitored.

Correlation of Surface and Interfacial Energies on Enhanced Pool Boiling Heat Transfer

Volume 3 ◽  
2004 ◽  
Author(s):  
Elva Mele´ndez ◽  
Rene´ Reyes
Keyword(s):  
Heat Transfer ◽  
Contact Angle ◽  
Surface Energy ◽  
Interfacial Energy ◽  
Boiling Heat Transfer ◽  
Contact Angles ◽  
Lauryl Sulfate ◽  
Surface Energies ◽  
Interfacial Energies ◽  
Set Up

The surface energy of the material used in the construction of capillary covers is an important element to increase the boiling heat transfer on the coverings. There are a variety of methodologies for measuring the surface energy of solids, but few could be used with the construction materials tested. The sessile drop methodology allows the evaluation of either the surface energy of solids or the interfacial energy of liquids. The methodology uses an image digitalization system for measuring the contact angle of liquids on the solid’s surface. The contact angles thus measured are used to calculate the superficial and interfacial energies. This methodology was tested with an experimental set up built for this study. The accuracy of the set up was obtained with clean and greased surfaces of high heat conductivity metals. The surface energies calculated were in accordance with previous experimental results. The surface energies of metal foils used for construction of capillary coverings were similar to the values calculated for the parental solid metal. The surfaces with different grease thickness get values of surface energy close to the value for the adhered hydrocarbons. The same methodology is used for measuring interfacial energies of pure and mixtures of liquids. The liquids studied include those used for increasing boiling heat transfer. Ethanol-water mixtures were analyzed. The mixture with 16% ethanol by weight had the lowest contact angle (associated to the lowest interfacial energy) and produced the highest convective heat transfer coefficient, h. A minimum in the value of the contact angle around the 16% weight ethanol mixtures follows the maximum in the value of h around this composition, and a maximum in the wettability. Similarly, the surfactant sodium-lauryl-sulfate (SLS) produced an increment of the wettability of the mixture on the solid surface. The reduction of the contact angle is obtained with the addition of 100 ppm of SLS or less, depending on the base metal, but above this concentration, the surfactant does not modify the value of the contact angle. The h values increased with the addition of surfactant up to 100 ppm but do not change if the concentration of surfactant is higher than that value.

Comparative Study of Surface Energies of Native Oxides of Si(100) and Si(111) via Three Liquid Contact Angle Analysis

MRS Advances ◽  
2018 ◽  
Vol 3 (57-58) ◽  
pp. 3379-3390 ◽  
Author(s):  
Saaketh R. Narayan ◽  
Jack M. Day ◽  
Harshini L. Thinakaran ◽  
Nicole Herbots ◽  
Michelle E. Bertram ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Sessile Drop ◽  
Surface Composition ◽  
Ion Beam ◽  
Contact Angles ◽  
Van Der Waals Interactions ◽  
Native Oxides ◽  
Relative Errors ◽  
Contact Angle Analysis

ABSTRACTThe effects of crystal orientation and doping on the surface energy, γT, of native oxides of Si(100) and Si(111) are measured via Three Liquid Contact Angle Analysis (3LCAA) to extract γT, while Ion Beam Analysis (IBA) is used to detect Oxygen. During 3LCAA, contact angles for three liquids are measured with photographs via the “Drop and Reflection Operative Program (DROP™). DROP™ removes subjectivity in image analysis, and yields reproducible contact angles within < ±1°. Unlike to the Sessile Drop Method, DROP can yield relative errors < 3% on sets of 20-30 drops. Native oxides on 5 x 1013 B/cm3 p- doped Si(100) wafers, as received in sealed, 25 wafer teflon boats continuously stored in Class 100/ISO 5 conditions at 24.5°C in 25% controlled humidity, are found to be hydrophilic. Their γT, 52.5 ± 1.5 mJ/m2, is reproducible between four boats from three sources, and 9% greater than γT of native oxides on n- doped Si(111), which averages 48.1 ± 1.6 mJ/m2 on four 4” Si(111) wafers. IBA combining 16O nuclear resonance with channeling detects 30% more oxygen on native oxides of Si(111) than Si(100). While γT should increase on thinner, more defective oxides, Lifshitz-Van der Waals interactions γLW on native oxides of Si(100) remain at 36 ± 0.4 mJ/m2, equal to γLW on Si(111), 36 ± 0.6 mJ/m2, since γLW arises from the same SiO2 molecules. Native oxides on 4.5 x 1018 B/cm3 p+ doped Si(100) yield a γT of 39 ± 1 mJ/m2, as they are thicker per IBA. In summary, 3LCAA and IBA can detect reproducibly and accurately, within a few %, changes in the surface energy of native oxides due to thickness and surface composition arising from doping or crystal structure, if conducted in well controlled clean room conditions for measurements and storage.

Use of Contact Angle Hysteresis in Estimating Thin Polymer Film Surface Energy and Wettability

2006 ◽  
Author(s):  
I. S. Bayer ◽  
C. M. Megaridis ◽  
J. Zhang ◽  
D. Gamota
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Surface Energy ◽  
Uv Radiation ◽  
Contact Angle Hysteresis ◽  
Estimation Methods ◽  
Thin Polymer Film ◽  
Energy Estimation ◽  
Surface Energies ◽  
Polar Probe

A recent surface energy estimation method [1] interpreting contact angle hysteresis measurements was used to estimate surface energy of various commercially important polymer films including UV radiation cross-linked acrylic based monomer systems. The validity of the method was tested on highly hydrophobic non-polar amorphous fluoro-polymers using a number of polar and low surface tension liquids. Contact angle hysteresis was present on these surfaces even though surface morphology of the solution processed fluoro-polymers is close to ideal. Estimated surface energies using such probe liquids were consistent varying slightly with the probe liquid type. On such highly ordered and non-polar polymer surfaces use of polar and low surface tension liquids results in accurate surface energy estimation. However, use of polar probe liquids commonly employed in surface energy estimation methods, such as, Harmonic mean (HM), Geometric mean (GM) or Lewis Acid-Base method (LWAB) on polar surfaces such as polyester resulted in inconsistent surface energy values. To strengthen this observation, the ASTM surface energy estimation procedure (ASTM D2578 04a) developed for polyethylene and polypropylene surfaces (both non-polar) was employed on a sample polar polyester surface using the ASTM probe liquids. Results showed inconsistent surface energy values supporting the conclusion that care must be exercised during use of polar probe liquids in estimating surface energy on polar polymers with the contact angle hysteresis method. Finally, UV radiation cross-linkable acrylic polymer surface energies were estimated with the hysteresis method. Surface energy results were consistent based on five different probe liquids. It was observed that surface energy of the cross-linked monomer networks decreased slightly with increasing UV curing time.

Effects of green technology plasma pre-treatment on the wettability and ink adhesion of paper

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Samed Ayhan Özsoy ◽  
Safiye Meriç Acıkel ◽  
Cem Aydemir
Keyword(s):  
Contact Angle ◽  
Plasma Treatment ◽  
Surface Properties ◽  
Atmospheric Pressure ◽  
Atmospheric Pressure Plasma ◽  
Contact Angles ◽  
Content Type ◽  
Surface Energies ◽  
Pressure Plasma ◽  
Plasma Device

Purpose The surface energy of the printing material can be increased to desired levels with different chemicals or methods. However, the important thing is that the surface properties of printing material are not affected negatively. In this way the aim of this paper provide that the surface properties of matte and glossy coated paper is improved by the argon containing atmospheric pressure plasma device because the plasma treatment method does not occur surface damaging on the papers. Design/methodology/approach In experimental studies, test samples cut from 160 mm × 30 mm in size from 115 g/m2 gloss- and matt-coated papers were used. The plasma treatments of paper samples were carried out with an argon containing atmospheric pressure plasma device of laboratory scale that produces plasma of the corona discharge type at radio frequency. The optimized plasma parameters were at a frequency of 20 kHz and plasma power 200 W. A copper electrode of length 12 cm and diameter 2.5 mm was placed in the centre of the nozzle. Findings Research findings showed that the surface energies of the papers increased with the increase in plasma application time. While the contact angle of the untreated glossy paper is 82.2, 8 second plasma applied G3 sample showed 54 contact angle value. Similarly, the contact angle of the base paper of matt coated is 91.1, while M3 is reduced to 60.4 contact angles by the increasing plasma time. Originality/value Plasma treatment has shown that no chemical coating is needed to increase the wettability of the paper surface by reducing the contact angle between the paper and the water droplet. In addition, the surface energies of all papers treated by argon gas containing atmospheric pressure plasma, increased. Plasma treatment provides to improve both the wettability of the paper and the adhesion property required for the ink, with an environmentally friendly approach.

scholarly journals Surface Energies of Tomato and Bell Pepper Cultivars

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 489E-489
Author(s):  
L. Cisneros-Zevallos ◽  
M.E. Saltveit ◽  
J.M. Krochta
Keyword(s):  
Surface Energy ◽  
Osmotic Dehydration ◽  
Contact Angles ◽  
Bell Pepper ◽  
Soluble Solids ◽  
Complete Wetting ◽  
Surface Energies ◽  
Fruit Processing ◽  
Hydrophobic Nature ◽  
Tomato Cultivars

Fruit processing treatments, such as osmotic dehydration, washing, aqueous dips and coatings applications, and even microbial adhesion, depend critically on the surface energy of surfaces. Knowledge of these values can be used as reference targets for treatment formulations when complete wetting is necessary. Unripened and ripened tomato cultivars, `Ace' and `Castlemart', and bell pepper cultivars `California Wonder' and `Garden Sunshine' were characterized by color, firmness, and soluble solids, and evaluated for their surface energy. Calculated surface energy was obtained using Fowkes' equation by measuring contact angles of a series of pure surfactants of different HLB values on the fruit surface and by comparing with a reference paraffin surface of 25.5 dynes/cm. Results indicated that surface energies were similar between both types of fruits, while there were differences between maturity stages for tomato fruits. Surface energy in all cases was lower than 30 dynes/cm, indicating the hydrophobic nature of the epicuticular surface of the fruits tested.

Influence of Surface Energy in the Osteogenesis Process of Treated Titanium Surfaces

2015 ◽  
Author(s):  
Lidiane Sartini de Oliveira ◽  
Cleudmar Amaral de Araújo ◽  
Fernando Lourenço de Souza ◽  
Gustavo Mendonça ◽  
Daniela B. S. Mendonça ◽  
...  
Keyword(s):  
Surface Energy ◽  
Bone Structure ◽  
Contact Angles ◽  
Nodule Formation ◽  
Acid Attack ◽  
Surface Energies ◽  
Biomechanical Behavior ◽  
Significant Difference ◽  
Bonferroni Test ◽  
Titanium Surfaces

In the 1960’s, Brånemark and colleagues developed a dental implant system using a direct attachment to bone structure without generating soft tissue. This phenomenon called osseointegration involves biomechanical behavior of materials. In several studies it has been verified that the surface treatment on titanium implant has been the main factor for the osteogenesis process and, consequently, osseointegration [1, 2, 3]. Treated titanium surfaces have better conditions for cell adhesion that can lead to load application in the shortest time. The aim of this study was to evaluate the surface energy and the cell osteogenesis on titanium discs under different conditions of blasting and acid attack. Osteoblastic cells Hfob 1.19 were used to measure cell culture parameters like cell viability and cell proliferation, alkaline phosphatase activity and mineralized nodule formation. Osteogenesis cell was defined through a mathematical model proposed by a similitude in engineering with osteogenic parameters analyzed in culture cells. Fowkes Theory was used to calculate the surface energy by measuring contact angles between liquid sensors (Deionized Water, Chloroform) on different titanium surfaces. Significant difference (P < 0,01) was observed for surface energies ranging between 26,76 a 33,81 mJ/m^2 using ANOVA and Bonferroni test. It was noted that the highest surface energies are related with osteogenesis levels.

scholarly journals Synthesis, Characterization and Wettability of Cu-Sn Alloy on the Si-Implanted 6H-SiC

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 906 ◽  
Author(s):  
Xiang Zhao Zhang ◽  
Pu Hao Xu ◽  
Gui Wu Liu ◽  
Awais Ahmad ◽  
Xiao Hui Chen ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Sessile Drop ◽  
Contact Angles ◽  
Graphite Layer ◽  
Sessile Drop Technique ◽  
Sic Ceramics ◽  
Sic Ceramic ◽  
Interfacial Chemical Reaction ◽  
Drop Technique

The wettability of the metal/SiC system is not always excellent, resulting in the limitation of the widespread use of SiC ceramic. In this paper, three implantation doses of Si ions (5 × 1015, 1 × 1016, 5 × 1016 ions/cm2) were implanted into the 6H-SiC substrate. The wetting of Cu-(2.5, 5, 7.5, 10) Sn alloys on the pristine and Si-SiC were studied by the sessile drop technique, and the interfacial chemical reaction of Cu-Sn/SiC wetting couples was investigated and discussed. The Si ion can markedly enhance the wetting of Cu-Sn on 6H-SiC substrate, and those of the corresponding contact angles (θ) are raised partly, with the Si ion dose increasing due to the weakening interfacial chemical reactions among four Cu-Sn alloys and 6H-SiC ceramics. Moreover, the θ of Cu-Sn on (Si-)SiC substrate is first decreased and then increased from ~62° to ~39°, and ~70° and ~140°, with the Sn concentration increasing from 2.5%, 5% and 7.5% to 10%, which is linked to the reactivity of Cu-Sn alloys and SiC ceramic and the variation of liquid-vapor surface energy. Particularly, only a continuous graphite layer is formed at the interface of the Cu-10Sn/Si-SiC system, resulting in a higher contact angle (>40°).

Estimation of casein micelles' surface energy by means of contact angle measurements

1989 ◽  
Vol 56 (2) ◽  
pp. 223-234 ◽  
Author(s):  
Michel Britten ◽  
Marcel Boulet ◽  
Paul Paquin
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Potential Energy ◽  
Short Range ◽  
Casein Micelle ◽  
Casein Micelles ◽  
Surface Energies ◽  
Angle Measurements ◽  
Heat Treated ◽  
Contact Angle Measurements

SummaryThe surface energies of highly hydrated casein micelle layers isolated from variously pretreated skim milks have been determined by means of contact angle measurements. The long range Lifshitz-Van der Waals (LW) and the short range hydrogen bonding (SR) components of surface energy were determined using α-bromonaphthalene and water for contact angle measurements. Casein micelles isolated from untreated and heat treated milks showed similar surface energy values of about 63·5 mJ.m-2 with an LW component of 19·2 mJ.m-2 and an SR component of 44·3 mJ.m-2. The calculated attraction potential energy was − 0·7 mJ.m-2. Casein micelles isolated from renneted milk showed a surface energy of 33·0 mJ.m-2 with an LW component of 30·7 mJ.m-2 and an SR component of 2·3 mJ.m-2. The attraction potential energy of renneted micelles was nearly two orders of magnitude higher than those of micelles from other milks ( − 63·3 mJ.m-2). The SR component of interfacial energy accounted for 98% of this attraction potential. The importance of attractive forces in relation to casein micelle stability is discussed.

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