scholarly journals Surface properties of extracts from cork black condensate

Holzforschung ◽  
2010 ◽  
Vol 64 (2) ◽  
Author(s):  
Ricardo A. Pires ◽  
João F. Mano ◽  
Rui L. Reis
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Solid Waste ◽  
Surface Properties ◽  
Protective Coating ◽  
Water Evaporation ◽  
Polar Component ◽  
Coating Surface ◽  
Surface Behavior ◽  
Chemical Groups

Abstract The insulation corkboard production generates black condensate (BC), a paste-like solid waste. It is hydrophobic and has the potential to be used as protective coating. To evaluate this potential, coatings were prepared from BC extracts and their surface behavior was evaluated by contact angle (CA) measurements. The CA dynamics were recorded as a function of time; advancing CAs were also registered; the approaches were applied according to Fowkes, Owens-Wendt-Rabel-Kaelble (OWRK), and Van Oss to determine the surface energy (SE) for each coating. Depending on the liquid probe, three phenomena were observed: water evaporation, diiodomethane diffusion into the coating, and rearrangement of the chemical groups on the coating surface, when glycerol was dropped onto the surface. Based on the results from the CA dynamics, the applicability of the coatings against hydrophobic environments was limited owing to its affinity to apolar compounds. The results show that the coating prepared by the toluene BC extract was the best coating. The key data were: water CA of 99.3°, total SE (between 37.4 mN m-1 and 40.1 mN m-1), SE polar component (0.1 mN m-1), and the acidic and basic characters were negligible. It can be concluded that the BC extracts have potential for coatings.

Effect of low-temperature plasma treatment and γ-irradiation on the surface properties of thin films based on polylactic acid

2020 ◽  
Vol 6 ◽  
pp. 40-55
Author(s):  
N.M. Ivanova ◽  
◽  
E.O. Filippova ◽  
A.N. Aleinik ◽  
V.F. Pichugin ◽  
...  
Keyword(s):  
Thin Films ◽  
Contact Angle ◽  
Low Temperature ◽  
Polylactic Acid ◽  
Surface Properties ◽  
Polar Component ◽  
Low Temperature Plasma ◽  
Plasma Exposure ◽  
Γ Irradiation ◽  
Temperature Plasma

Effects of the low-temperature plasma exposure, γ-irradiation, and joint g-irradiation and plasma exposure on the structure and surface properties of thin films based on polylactic acid (PLA) have been investigated. Films were obtained by the method a solvent-casting. It has been shown that films based on polylactic acid have topographically different sides: a smoother inner side and embossed outer one. PLA films have properties close to those hydrophobic, with a contact angle in the range of 70°-73° regardless of the surface side and belong to a weakly polar materials. The combined effect of plasma and gamma radiation slightly changes the surface topography. The effect of low-temperature plasma on the surface of the films leads to a decrease in the contact angle by 13°-55° (9-11%) and an increase in surface energy due to the polar component. The results of in vivo experiments on rabbits are presented. Biomicroscopy, optical coherence tomography, morphological and electron microscopic examination of the cornea after implantation of initial and radiation and plasma treated films showed that implantation of the films in the anterior chamber is not accompanied by a pronounced inflammatory reaction and increased intraocular pressure, while maintaining the morphological structure of the cornea almost unchanged.

Surface Modification of Calcium Hydroxyfluor Carbonate Apatites by Bisphosphonates

2005 ◽  
Vol 284-286 ◽  
pp. 357-360 ◽  
Author(s):  
Luis M. Rodríguez-Lorenzo ◽  
Blanca Vázquez ◽  
Julio San Román
Keyword(s):  
Thermal Analysis ◽  
Contact Angle ◽  
Weight Loss ◽  
Surface Modification ◽  
Bone Resorption ◽  
Ir Spectroscopy ◽  
Surface Energy ◽  
Cellular Interaction ◽  
Polar Component ◽  
Carbonate Apatite

Hydroxyapatite has been frequently described as an osteoconductive but not osteoinductive material based on failure to observe bone formation in nonbony sites. Bisphosphonates (BPs) are stable pyrophosphate analogs, that enhance the proliferation, differentiation and bone forming activity of osteoblasts and are potent inhibitors of bone resorption. In this paper, the modification of a calcium hydroxyfluor carbonate apatite with sodium alendronate and (4-(aminomethyl)benzene)bisphosphonic acid is described. The surface modification is carried out by refluxing the apatite in a bisphosphonate acetone solution. Modified particles are characterized by thermal analysis, ATR-IR spectroscopy and contact angle between other techniques. A weight loss between 150 and 500°C can be observed for the modified apatites. IR spectra show the appearance of bisphosphonate bands on modified powders. The surface energy of the modified apatite is reduced up to a 74% from the total apatite value after the alendronate surface modification with a decrease of 58% of the polar component main responsible of the cellular interaction of biomaterials.

EFFECT OF SURFACE PROPERTIES ON THE WETTABILITY OF IRON CONTAINING AMORPHOUS CARBON FILMS

2002 ◽  
Vol 16 (06n07) ◽  
pp. 1031-1037 ◽  
Author(s):  
J. S. CHEN ◽  
S. P. LAU ◽  
Z. SUN ◽  
G. Y. CHEN ◽  
Y. J. LI ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Amorphous Carbon ◽  
Photoelectron Spectroscopy ◽  
Contact Angle Measurement ◽  
Carbon Films ◽  
Angle Measurement ◽  
Vacuum Arc ◽  
Polar Component ◽  
Dispersive Component

Ta-C and iron containing amorphous carbon (a-C:Fe) films were deposited by filtered cathodic vacuum arc technique. The influences of Fe contents on the wettability of the films were investigated in terms of surface energy. The surface energy of a-C:Fe films was determined by the contact angle measurement. Atomic force microscopy (AFM), Raman spectroscopy and X-ray induced photoelectron spectroscopy (XPS) were employed to analyze the origin of the variation of surface energy with various Fe content. It is found that the contact angle for water increases significantly after incorporating Fe into the films and the films become hydrophobic. The roughness of these films has a little effect on the contact angle. The surface energy is reduced after incorporating Fe into the a-C film which is due to the reduction of both dispersive and polar component. The reduction in dispersive component is ascribed to the decrease of atomic density of the a-C:Fe films due to the increase in sp2 bonded carbon. The absorption of oxygen on the surface play an important role in the reduction of polar component for the a-C:Fe films. It is proposed that such network as (Ca-O-Fe)-O-(Fe-O-Ca) may be formed and responsible for the reduction of polar component.

Anti-Sticking Properties of PVD CrWNx, CrOx and ZrOx Coatings on Medical Electrode Application

2010 ◽  
Vol 297-301 ◽  
pp. 656-663
Author(s):  
Y.L. Hsu ◽  
C.H. Lee ◽  
S.M. Chiu ◽  
Y.C. Sung ◽  
K.Y. Yang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
High Surface ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Polar Component ◽  
In Vitro Test ◽  
Unbalanced Magnetron Sputtering ◽  
Unbalanced Magnetron

The side effect of electrosurgery includes tissue charring, smoke generation and the adhesion of tissue to electrodes. These effects prolong surgery and interfere with effective coagulation. In this paper, CrWNx, CrOx and ZrOx coating were prepared by an unbalanced magnetron sputtering. The microstructure of films was characterized using XRD, XPS, TEM and AFM. The hydrophobicity and surface energy of coatings were calculated by contact angle measurement and Wu harmonic mean approach. Anti-sticking in vitro test was performed by monopolar electrosurgery using pork liver tissue. The hardness of CrWNx , ZrOx and CrOx coatings were 44 GPa, 26.3 GPa and 20.7 GPa, respectively. The CrOx coating had the lowest surface energy 33.5 mN/m and the highest contact angle of water as high as 103°. The high surface O-H bonds density of CrOx coating and N-H bonds density of CrWNx coating could explain about their lower polar component of surface energy. All the three PVD coatings remarkably reduced the quantity of tissue adhesion on the electrode from about 2 times (ZrOx and CrWNx coatings) to 4.88 times (CrOx coating) than uncoated SUS304 electrode.

On the Wettability of Nanocomposite Amorphous Carbon Films

2005 ◽  
Vol 23 ◽  
pp. 67-70
Author(s):  
P. Zhang ◽  
B.K. Tay ◽  
G.Q. Yu ◽  
S.P. Lau
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Amorphous Carbon ◽  
Photoelectron Spectroscopy ◽  
Contact Angles ◽  
Atomic Scale ◽  
Vacuum Arc ◽  
Polar Component ◽  
Metal Composite ◽  
Obvious Effect

Nanocomposite Si containing amorphous carbon (a-C:Si) and metal containing amorphous carbon (a-C:Me) films including a-C:Al, a-C:Ti, and a-C:Ni were prepared by the filtered cathodic vacuum arc (FCVA) technique The metal-carbon (5 at.% metal) composite targets were used. The VCA Optima system was used to measure the contact angle. Three types of liquid were used to study the changes in the surface energy. X-ray photoelectron spectroscopy (XPS) was employed to analyze the composition and chemical state of the films. The surface morphology and roughness of the films were determined by atomic force microscopy (AFM). The Al containing films show the highest contact angle with water, which reaches as high as 101.26°. The Si containing films show the lowest contact angle around 64°. The contact angles of Ni, and Ti containing films are around 83°, 96.5°, respectively. The absorption of oxygen on the surface play an important role on the polar component of the a-C:Me films. The formation of Al-O, and Ti-O bonds is responsible for the lower polar component. The metal state Ni results in higher polar component. The Si-O bond contributes to the high polar component of a-C:Si film. As all films are atomic scale smooth, the RMS roughness is below 0.5 nm, the roughness does not have obvious effect on the surface energy.

scholarly journals Evaluation of the Physical Performance and Working Mechanism of Asphalt Containing a Surfactant Warm Mix Additive

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Jingtao Shi ◽  
Weiyu Fan ◽  
Tihong Wang ◽  
Pinhui Zhao ◽  
Fa Che
Keyword(s):  
Contact Angle ◽  
Spectral Analysis ◽  
Surface Energy ◽  
Asphalt Mixtures ◽  
Polar Component ◽  
Zero Shear Viscosity ◽  
Working Mechanism ◽  
Water Contact ◽  
Temperature Characteristics ◽  
Physical Blending

This paper analyzes the influence of a surfactant warm mix additive on unmodified asphalt’s conventional performance, viscosity-temperature characteristics, surface energy, and spreading performance on aggregate surfaces. The effect of the additive on asphalt’s microstructure was explored by infrared (IR) spectral analysis. The results show the additive has little influence on the penetration, softening point, ductility, and viscosity-temperature characteristics of asphalt; this suggests that the additive does not work by lowering viscosity. The additive can reduce the zero-shear viscosity of asphalt, and adding too much can reduce antirutting performance. The additive also increases the asphalt’s surface energy and the asphalt-water contact angle, while the polar component of surface energy decreases. The additive improves the spreading performance of asphalt on aggregate surfaces and reduces the asphalt-aggregate contact angle; the lower the temperature, the greater the reduction. IR spectral analysis shows that the additive does not react with asphalt—only physical blending occurs. The addition of a surfactant warm mix additive to asphalt allows asphalt mixtures to be more easily mixed and compacted at lower temperatures, thereby saving energy.

Increasing Storage Modulus, Contact Angle and Surface Tension of Airway Mucus Increases Clearance by Simulated Cough Through a Model Trachea

2010 ◽  
Author(s):  
Anpalaki J. Ragavan ◽  
Cahit A. Evrensel ◽  
Peter Krumpe
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Storage Modulus ◽  
Surface Properties ◽  
Respiratory Diseases ◽  
Interactive Effects ◽  
Altered Surface ◽  
Human Trachea ◽  
Tension Increase ◽  
And Storage

Altered surface and viscoelastic material properties of mucus during respiratory diseases have a strong influence on its clearance by cilia and cough. Combined effects of the surface properties (contact angle and surface tension) and storage modulus with relatively unchanged viscosity on displacement of the simulated mucus aliquot during simulated cough through a model adult human trachea is investigated. For the mucus simulants used in this study contact angle and surface tension increase significantly as storage modulus increase while viscosity remains practically unchanged. Displacement of mucus simulant aliquots increased significantly with increasing storage modulus (and contact angle) at a given cough velocity in the range between 5 meters/second (m/s) and 30 m/s with duration 0.3 s. Results suggest that the interactive effects of elasticity and surface properties may help facilitate mucus displacement at low cough velocities.

A look into the interaction of metal oxide thin films with biological media: Albumin and Fibrinogen adsorption

2012 ◽  
Vol 1376 ◽  
Author(s):  
P. Silva-Bermudez ◽  
S. Muhl ◽  
M. Rivera ◽  
S. E. Rodil
Keyword(s):  
Surface Roughness ◽  
Surface Energy ◽  
Protein Adsorption ◽  
Photoelectron Spectroscopy ◽  
Ex Situ ◽  
Polar Component ◽  
Metal Oxide Thin Films ◽  
Adsorbed Protein ◽  
Major Chemical ◽  
Fibrinogen Adsorption

ABSTRACTIn the present work, the adsorption of albumin and fibrinogen on Ta, Nb, Ti and Zr oxidesthin films deposited on Si (100) wafers by magnetron sputtering was studied in order to get a better understanding of the correlation among the surface properties of these oxides and the protein adsorption phenomena on their surfaces. The surface energy, hydrophobicity, chemical composition, roughness and atomic order of the films were characterized. The films were immersedfor 45 minutes in single protein solutions; either albumin or fibrinogenand the adsorbed protein layer on the films was studied ex-situ in a dry ambient using bothX-ray photoelectron spectroscopy and atomic force microscopy.The adsorption of albumin and fibrinogen on the films modified the surface morphology and decreased the surface roughness for all the four different metal oxides. The XPS results confirmed the presence of the protein on the surface of the films and showed that the two proteins studied were adsorbed without undergoing a major chemical decomposition. A correlation between the surface roughness,the polar component of the surface energy of the films and the atomic percentage of nitrogen on the films after protein adsorption, an indirect signal of the amount of protein adsorbed, was found for albumin and fibrinogen adsorption on Ta, Nb and Ti oxides; the largest the roughness or the polar component the largest amount of adsorbed protein.

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