scholarly journals Consolidation of Fir Wood by Poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) Treatment: Study of Surface and Mechanical Characteristics

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1039
Author(s):  
Danial Harandi ◽  
Javier González-Benito ◽  
Dania Olmos
Keyword(s):  
Mechanical Properties ◽  
Contact Angle ◽  
Vinyl Acetate ◽  
Vinyl Alcohol ◽  
Untreated Wood ◽  
Hydrophobic Surface ◽  
Solution Concentration ◽  
Bending Test ◽  
Water Contact ◽  
Vinyl Butyral

The ability of poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) (PVBVA) to consolidate Fir wood was studied in terms of the surface and mechanical properties’ changes. Two variables were considered to treat the wood: (i) the concentration (5 and 10 wt.%) of PVBVA solutions and (ii) the method of application (brushing and immersion). The presence of PVBVA on the wood surfaces was confirmed by infrared spectroscopy. Surface roughness measured by optical profilometry did not reveal changes in the topography of the samples, and appropriate visual appearance was confirmed. Contact angle measurements showed that a droplet of the 10%-PVBVA solution needed ~50 s to reach the same contact angle decreasing rate as that measured for the 5%-PVBVA solution, suggesting there was some kind of induction time till the spreading process was no longer controlled by the viscosity, but by the solution-wood interactions. Water contact angle (WCA) measurements proved a more hydrophobic surface of the PVBVA-treated samples, compared to untreated wood. Mechanical characterization of the samples was done macroscopically by a three-point bending test and locally by the Shore D and Martens hardness (MH). Only results from MH experiments provided comparative results, indicating that treatment with PVBVA solutions increased wood hardness locally, being enhanced with solution concentration. The best surface mechanical properties were obtained for the samples immersed in the 10%-PVBVA solution.

scholarly journals Effect of ethanol post-treatment on the bubble-electrospun poly(vinyl alcohol) nanofiber

2015 ◽  
Vol 19 (4) ◽  
pp. 1353-1356 ◽  
Author(s):  
Jiang-Hui Zhao ◽  
Lan Xu ◽  
Qixia Liu
Keyword(s):  
Mechanical Properties ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Vinyl Alcohol ◽  
Post Treatment ◽  
Poly Vinyl Alcohol ◽  
Water Contact ◽  
Angle Change ◽  
Potential Benefits

Poly(vinyl alcohol) nanofibers were prepared by bubble electrospinning. After the ethanol post-treatment, poly(vinyl alcohol) nanofibers showed enhanced hydrophobicity with water contact angle change from 0 to 78.9?, and the break strength of poly(vinyl alcohol) nanofibers was dramatically improved from 8.23 MPa to 17.36 MPa. The facile strategy with improved hydrophobicity and mechanical properties of poly(vinyl alcohol) nanofibers will provide potential benefits for applications of this material, especially in filtration field.

Osteoconductivity of Superhydrophilic Ti- and Zr-Alloy for Biomedical Application

2016 ◽  
Vol 879 ◽  
pp. 2524-2527
Author(s):  
Masazumi Okido ◽  
Kensuke Kuroda
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Strong Influence ◽  
Biomedical Application ◽  
Hydrophobic Surface ◽  
Hydrophilic Surface ◽  
Water Contact ◽  
Zr Alloy ◽  
Zr Alloys

Surface hydrophilicity is considered to have a strong influence on the biological reactions of bone-substituting materials. However, the influence of a hydrophilic or hydrophobic surface on the osteoconductivity is not completely clear. In this study, we produced super-hydrophilic and hydrophobic surface on Ti-and Zr-alloys. Hydrothermal treatment at 180 oC for 180 min. in the distilled water and immersion in x5 PBS(-) brought the super-hydrophilic surface (water contact angle < 10 (deg.)) and heat treatment of as-hydrothermaled the hydrophobic surface. The osteoconductivity of the surface treated samples with several water contact angle was evaluated by in vivo testing. The surface properties, especially water contact angle, strongly affected the osteoconductivity and protein adsorbability, and not the surface substance.

scholarly journals Superhydrophobic textile: treatment in aqueous solutions of aluminum salts

2021 ◽  
Author(s):  
Eterina Endiiarova ◽  
Artem Osipov ◽  
Sergey Alexandrov ◽  
Alexander Shakhmin
Keyword(s):  
Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Superhydrophobic Surface ◽  
Hydrophobic Surface ◽  
Solution Concentration ◽  
Textile Processing ◽  
X Ray ◽  
Textile Materials ◽  
Aluminum Salts ◽  
Processing Treatment

Abstract Textile is currently a promising material. Obtaining hydrophobic surfaces on textiles significantly increases its value when used in various fields. In this work we carried out experiments on textile processing. Treatment of textile materials in solutions containing aluminum allows to obtain a superhydrophobic surface. KAl(SO4) and AlCl3 solutions were used. It was found that treatment in AlCl3 solution is more effective and allows to achieve a hydrophobic surface on textile with a contact angle of more than 150º. The hydrophobic surface retained its properties even after 30 days. Textile samples were investigated using X-Ray photoelectron spectroscopy (XPS). The X-Ray photoelectron spectroscopy results showed hydrophobicity in the treatment of textile materials is ensured by the formation of aluminum oxide on the surface. The dependence of the coarse calico contact angle on the AlCl3 solution concentration is determined. which demonstrates that when the concentration of AlCl3 solution increases (within the limits of variation considered), the contact angle also increases.

scholarly journals One-Step Preparation of Durable Super-Hydrophobic MSR/SiO2 Coatings by Suspension Air Spraying

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 677 ◽  
Author(s):  
Zhengyong Huang ◽  
Wenjie Xu ◽  
Yu Wang ◽  
Haohuan Wang ◽  
Ruiqi Zhang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Adhesion Strength ◽  
Contact Angle Hysteresis ◽  
Surface Hardness ◽  
Hierarchical Structures ◽  
Hydrophobic Surface ◽  
Water Contact ◽  
Hydrophobic Coating ◽  
Mechanical Durability ◽  
One Step

In this study, we develop a facial one-step approach to prepare durable super-hydrophobic coatings on glass surfaces. The hydrophobic characteristics, corrosive liquid resistance, and mechanical durability of the super-hydrophobic surface are presented. The as-prepared super-hydrophobic surface exhibits a water contact angle (WCA) of 157.2° and contact angle hysteresis of 2.3°. Mico/nano hierarchical structures and elements of silicon and fluorine is observed on super-hydrophobic surfaces. The adhesion strength and hardness of the surface are determined to be 1st level and 4H, respectively. The coating is, thus, capable of maintaining super-hydrophobic state after sand grinding with a load of 200 g and wear distances of 700 mm. The rough surface retained after severe mechanical abrasion observed by atomic force microscope (AFM) microscopically proves the durable origin of the super-hydrophobic coating. Results demonstrate the feasibility of production of the durable super-hydrophobic coating via enhancing its adhesion strength and surface hardness.

scholarly journals Poly (Vinyl Butyral-Co-Vinyl Alcohol-Co-Vinyl Acetate) Coating Performance on Copper Corrosion in Saline Environment

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 439
Author(s):  
Adriana Samide ◽  
Claudia Merisanu ◽  
Bogdan Tutunaru ◽  
Gabriela Eugenia Iacobescu
Keyword(s):  
Vinyl Acetate ◽  
Vinyl Alcohol ◽  
Electrochemical Impedance ◽  
Copper Surface ◽  
Copper Sample ◽  
Electrochemical Measurements ◽  
Copper Corrosion ◽  
Nacl Solution ◽  
Force Microscopy ◽  
Vinyl Butyral

Poly (vinyl butyral-co-vinyl alcohol-co-vinyl acetate) named further PVBA was investigated as a protective coating for copper corrosion in 0.9% NaCl solution using electrochemical measurements such as, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization associated with atomic force microscopy (AFM). The PVBA coating on the copper surface (Cu-PVBA) was modeled in methanol containing PVBA. Its inhibitory properties against corrosion was comparatively discussed with those of the copper sample treated in methanol without polymer (Cu-Me) and of untreated sample (standard copper). A protective performance of PVBA coating of 80% was computed from electrochemical measurements, for copper corrosion in NaCl solution. Moreover, AFM images designed a specific surface morphology of coated surface with PVBA, clearly highlighting a polymer film adsorbed on the copper surface, which presents certain deterioration after corrosion, but the metal surface was not significantly affected compared to those of untreated samples or treated in methanol, in the absence of PVBA.

An Effective Route to the Fabrication of Super-Hydrophobic Surfaces Combined by Micromolding and Photograft Polymerization Methods

2012 ◽  
Vol 152-154 ◽  
pp. 9-13
Author(s):  
Jing Tao Yang ◽  
Lei Wang ◽  
Zheng Yuan Huo ◽  
Jie Feng ◽  
Feng Chen ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Energy Dispersive Spectrometer ◽  
Hydrophobic Surface ◽  
Body Structure ◽  
Critical Difference ◽  
Water Contact ◽  
Methacrylate Monomers ◽  
Polypropylene Matrix ◽  
Morphology Characterization

A super-hydrophobic surface on the polypropylene matrix was fabricated via micromolding and photograft polymerization. A micro-convex body structure was molded by etching templates. The water contact angle could be increased to 138°. The fluoro methacrylate monomers were further grafted to the surface through UV-induced photograft polymerization. The morphology characterization and the spectroanalysis indicated that the rough hierarchical structure (confirmed by scanning electron microscope) and the grafted fluoropolymers (measured by fourier transform infrared spectrum and X-ray energy dispersive spectrometer) made a critical difference. A water contact angle of 160° was arrived.

Synthesis and characterization of novel polysiloxane-grafted fluoropolymers

2005 ◽  
Vol 83 (6-7) ◽  
pp. 553-558 ◽  
Author(s):  
Bilal Baradie ◽  
Patricia HM Lai ◽  
Molly S Shoichet
Keyword(s):  
Carbon Dioxide ◽  
Thermal Stability ◽  
Supercritical Carbon Dioxide ◽  
Vinyl Acetate ◽  
Vinyl Alcohol ◽  
Contact Angles ◽  
Synthesis And Characterization ◽  
Water Contact ◽  
Degradation Temperature

Fluorosilicone polymers combine the properties of both fluorocarbons and siloxanes, yielding materials with unique properties. Novel crosslinked fluorosilicone polymers were synthesized by grafting diisocyanate-terminated polydimethylsiloxane (PDMS) to hydroxyl-functionalized fluoropolymers of poly(tetrafluoroethylene-co-vinyl acetate-co-vinyl alcohol) (PTFE-VAc-VA), as confirmed by elemental bulk and surface analysis. The fluorosilicone polymers containing 34 mol% of TFE were thermally stable with a degradation temperature of 267 °C. Fluorosilicone films were found to be more hydrophobic than the parent, non-grafted fluoropolymers; dynamic advancing and receding water contact angles for PTFE-co-VAc-co-VA-g-PDMS were 104° ± 1° and 61° ± 1°, respectively, whereas for PTFE-co-VAc they were 90° ± 2° and 59° ± 2°. The combined properties of thermal stability and hydrophobicity suggest that these fluorosilicones may be useful for coating and paint applications.Key words: fluoropolymers, fluorosilicone, polydimethylsiloxane, supercritical carbon dioxide.

Hydrophobic Performance of Core/Shell Nanoarrays Modified by Stearic Acid

2020 ◽  
Vol 15 (2) ◽  
pp. 264-268
Author(s):  
Hongxing Han ◽  
Lin Pan ◽  
Manying Zhang ◽  
Lei Zhao ◽  
Zhifeng Liu
Keyword(s):  
Contact Angle ◽  
Stearic Acid ◽  
Water Contact Angle ◽  
Zno Nanorods ◽  
Hydrophobic Surface ◽  
Optical Transmittance ◽  
Surface Hydrophobicity ◽  
Core Shell ◽  
Water Contact ◽  
Angle Measurements

In this paper, we successfully prepare hydrophobic surface of ZnO/ZnS nanorods arrays modified by stearic acid. The morphology, microstructure, optical transmittance and self-cleaning property are examined by SEM, XRD, UV-vis and water contact angle measurements, respectively. The ZnO/ZnS core/shell nanoarrays shows a higher value of water contact angle in compare with that of pure ZnO nanorods arrays. After treatment by stearic acid, the resulting ZnO/ZnS nanostructure exhibits the best hydrophobicity with water droplets about 146.5 . The results show that the surface hydrophobicity of ZnO/ZnS nanoarrays can be improved by using stearic acid with low-surface-energy.

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