Formation of Super-Hydrophobic Surface by Accumulating Pollution on RTV Silicone Rubber Coating Surface

2014 ◽  
Vol 875-877 ◽  
pp. 1520-1524
Author(s):  
Yue Ju Zhao ◽  
Guo Gang Wang ◽  
Jin Ling Zhang ◽  
Jian Hui Wang
Keyword(s):  
Contact Angle ◽  
Silicone Rubber ◽  
Hydrophobic Surface ◽  
Dust Particles ◽  
Water Contact ◽  
Coating Surface ◽  
Static Contact ◽  
Rubber Coating ◽  
Pollution Accumulation ◽  
Rtv Silicone Rubber

The Super-hydrophobic surface can be obtained easily by pollution accumulation on room temperature vulcanized (RTV) silicone rubber coating surface. The photos taken by digital camera show that the amount of pollution on the RTV coating surface was increased with time, and after one year, the RTV coating surface nearly could hardly be seen. The water state contact angle (CA) measurement, which was investigated by the static contact angle instrument, reveals that the CA value of RTV coating surface is increased with increasing the pollution accumulation, and in suitable amount of pollution accumulation, the super-hydrophobic surface (water contact angle of 152o and roll-off angle smaller than 5 o) was obtained. The scanning electric microscope (SEM) of RTV coating with different pollution accumulation was investigated. It shows that the continuous micro-nanobinary structure can be formed with enough dust particles on the RTV surface. The mechanism of the effect of pollution accumulation on the wetting property was analyzed, the migration of hydrophobic molecular in RTV coating onto the pollution surface and the formation of micro-nanobinary structure on the RTV coating surface have synergistic effect on the super-hydrophobic surface formation caused by the pollution accumulation.

Superhydrophobic RTV Silicone Rubber Coatings on Anodized Aluminium Surfaces

2012 ◽  
Vol 706-709 ◽  
pp. 2546-2551 ◽  
Author(s):  
Gelareh Momen ◽  
Masoud Farzaneh
Keyword(s):  
Contact Angle ◽  
Silicone Rubber ◽  
Room Temperature ◽  
Water Contact ◽  
Angle Measurements ◽  
Atomic Force ◽  
Static Contact ◽  
Contact Angle Measurements ◽  
Rubber Coatings ◽  
Rtv Silicone Rubber

A superhydrophobic surface was elaborated using two inexpensive industrial processes: surface anodization in phosphoric acid and spin coating of the anodized surface by RTV silicone rubber. Scanning electron microscopy (SEM), atomic force microscopic (AFM) and water contact angle measurements have been performed to characterize the morphological features, and wettability of the surfaces. The water static contact angle of the elaborated surface reached 157 ° at room temperature. At supercool temperature (-10°C) the superhydrophobic coating showed an important delayed freezing time.

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 A Simple Method to Create Superhydrophobic Aluminium Surfaces

2012 ◽  
Vol 706-709 ◽  
pp. 2874-2879 ◽  
Author(s):  
R. Jafari ◽  
Masoud Farzaneh
Keyword(s):  
Contact Angle ◽  
Stearic Acid ◽  
Synergistic Effects ◽  
Low Cost ◽  
Contact Angle Hysteresis ◽  
Spray Coating ◽  
Superhydrophobic Surfaces ◽  
Water Contact ◽  
Simple Method ◽  
Static Contact

Superhydrophobic surfaces were prepared using a very simple and low-cost method by spray coating. A high static water contact angle of about 154° was obtained by deposition of stearic acid on an aluminium alloy. However, this coating demonstrated a high contact angle hysteresis (~ 30º). On the other hand, superhydrophobic surfaces with a static contact angle of about 162º and 158º, and a low contact angle hysteresis of about 3º and 5º were respectively obtained by incorporating nanoparticles of SiO2and CaCO3in stearic acid. The excellent resulting hydrophobicity is attributed to the synergistic effects of micro/nanoroughness and low surface energy. A study of the wettability of these surfaces at temperatures ranging from 20 to-10 °C showed that the superhydrophobic surface becomes rather hydrophobic at supercooled temperatures.

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.

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.

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.

Research on the Strengthen of Silicone Rubber

2013 ◽  
Vol 663 ◽  
pp. 377-380 ◽  
Author(s):  
Wen Juan Gu ◽  
Ying Li ◽  
Bang Gui He
Keyword(s):  
Mechanical Property ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Silicone Rubber ◽  
Sol Gel ◽  
Water Contact ◽  
Gel Method ◽  
Sol Gel Method ◽  
Strain Stress ◽  
Strengthen Mechanism

A new kind of microsphere filler was synthesized with octyltrimethoxysilane (WD13) and tetraethoxysilane (TEOS) by sol-gel method. The morphology of the filler was measured by TEM. The so synthesized spheres were added into the silicone rubber. Both the strain-stress and the water contact angle of the silicone rubber were researched. The results showed that both the mechanical property and the hydrophobic performance of the composite were improved compared with the blank specimen. The possible strengthen mechanism of the filler was discussed. The neotype silica sphere researched in this paper could react with the silicone rubber chains which perfects the vulcanization of the silicone rubber. This kind of sphere filler exhibits many merits for usage as filler.

scholarly journals Hydrophobic zinc-tellurite glass system as self-cleaning vehicle: Interplay amid SiO2 and TeO2

2018 ◽  
Vol 14 ◽  
pp. 492-494
Author(s):  
Siti Nur Nazhirah Mazlan ◽  
Ramli Arifin ◽  
Sib Krishna Ghoshal
Keyword(s):  
Contact Angle ◽  
Hydrophobic Interactions ◽  
Hydrophobic Surface ◽  
Cost Effective ◽  
Underlying Mechanism ◽  
Industrial Applications ◽  
Glass System ◽  
Preparation Technique ◽  
Water Contact ◽  
Self Cleaning

Cost-effective, environmental amiable and maintenance free glasses with improved hydrophobic activity are needed for diverse industrial applications. Pollutant and dirt depositions on glasses that cause the visual obscurity and damages of the cultural heritages require inhibition. The underlying mechanism of hydrophobic interactions assisted self-cleaning traits of glass is poorly understood. It has been shown that excellent hydrophobic glass with water contact angle (WCA) above 90o and very low surface wettability can be achieved by controlling the surface roughness (SR), where liquid droplets remain perfectly spherical on such surfaces (literally without touching) before being self-cleaned (rolls off). Moreover, selection and optimization of constituent materials composition as well as the preparation technique play a significant role towards such success. Most of the previous attempts for the self-cleaning glass preparation were made via coating strategy on glass surface. Yet, preparation of super-hydrophobic glass surfaces with self-cleaning attributes remains an open challenge. Driven by this idea, we prepared a new glass system of composition (80 x) TeO2-20ZnO-(x)SiO2 (x = 0, 0.03, 0.06, 0.09 and 0.12 mol%) by melt-quenching method, where the proportions of SiO2 and TeO2 were interplayed. As-prepared samples (thin pellet without coating) were characterized using atomic force microscopy (AFM) and video contact angle (VCA) measurements. The effects of SiO2 concentration on the glass SR, surface energy and hydrophobic properties were evaluated. Glass 0.06 mol% of SiO2 revealed the optimal WCA of 112.39º and SR of 7.806 nm. It was established that a trade-off between SiO2 and TeO2 contents in the studied glasses could produce super-hydrophobic surface (WCA over 90º), leading to great opportunities for diverse self-cleaning applications.

Effects of Titanium Surface Wettability on Osteoblast Behavior In Vitro

2020 ◽  
Vol 985 ◽  
pp. 64-68
Author(s):  
Kenta Nisogi ◽  
Satoshi Okano ◽  
Sengo Kobayashi ◽  
Kensuke Kuroda ◽  
Takeaki Okamoto
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Titanium Surface ◽  
Pure Titanium ◽  
Hydrophobic Surface ◽  
Surface Wettability ◽  
In Vitro Assays ◽  
Water Contact ◽  
Heat Treated

Surface wettability is thought to influence the osteoconductivity of bone-substituting materials; however, the effects of surface wettability on osteoblast behavior are not well understood. In this study, we prepared both an as-polished pure titanium with a water contact angle (WCA) of 57° and heat-treated pure titanium with more hydrophobic surface and WCAs of 68°-98°. The effects of the surface wettability of pure titanium on osteoblast behaviors were evaluated by in vitro assays. Compared with the as-polished titanium, the proliferation rate of osteoblast increased on heat-treated titanium. This suggested that surface wettability affects osteoblast behaviors, meaning osteoconductivity is influenced by surface wettability.

Research on the Formula of Polyaspartic Ester Polyurea Concrete Coating and its Application

2013 ◽  
Vol 423-426 ◽  
pp. 1159-1163 ◽  
Author(s):  
Jing Feng ◽  
Ling Min Liao ◽  
Liang Chen ◽  
Cheng Jing Xiao ◽  
Shan Feng Wang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Crack Resistance ◽  
Water Contact Angle ◽  
Bonding Strength ◽  
Testing Machine ◽  
Weight Ratio ◽  
Hydrophobic Surface ◽  
Water Contact ◽  
North Water ◽  
Concrete Coating

Its of great importance to develop various outstanding protective concrete coating with favorable impermeability and crack-resistance properties. In this study, the polyaspartic ester polyurea was prepared, and its adhesion to concrete was evaluated by universal testing machine and SEM technology. The optimal formula of polyurea was obtained by investigating the effects of each component's content on the bonding strength to concrete and the water contact angle. Subsequently, the mechanical and surface properties of these polyurea coating were tested. The results showed that the polyurea was obtained by the following formula: the weight ratio of A1/A2/B was 0.612/ 0.408/ 1, and the fluoride filler content was 3%. The coating exhibited excellent mechanical properties, such as high bonding strength (4.5 MPa), sufficient tensile strength (16.4 MPa) and elongation at break (456%). Meanwhile, the coating showed a hydrophobic surface with its water contact angle of 105°. Hence, the polyurea coating is likely to improve the crack-resistance and impermeability properties of hydraulic concrete. Till now, the polyurea coating has been applied to the concrete repair and protection engineering in the South-to-North Water Transfers Project.

Sign in / Sign up

Export Citation Format

Share Document