• Structural Engineering and Mechanics
• /
• v.86 no.1
• /
• pp.109-118
• /
• 2023

Any place where exercise is common, such as a club, sports hall, or school, is considered a place for teaching sports. When doing sports, a very safe environment for sports should be chosen. The athlete should consider the safety of sports facilities and equipment, and if there is a defect, he should refrain from exercising in these places. The safety of sports facilities is very effective in creating people's sports activities, with the benefits of staying away from physical harm, enjoying sports, and having mental peace. Everyone has the right to participate in sports and recreation and to ensure that they enjoy a safe environment. The ability to manage and solve issues that may arise plays the most critical role in creating a safe environment. The quality of construction materials used for the construction of sports facilities is of great importance. In this work, the resistance and water repellency of concrete constituents for the construction of sports buildings have been investigated by nanoscience. Nano-concrete material solves the main problem of concrete surfaces, i.e., the entry of water and humidity into the structure. It also gives it a self-cleaning ability with its water repellency. Nanoparticles are placed between pores and cover the cracks, which causes roughness in the surface structure of concrete. The high roughness of the surface of the coated concrete caused its super-hydrophobicity. In hydrophobic surfaces, the higher the contact angle, the more hydrophobic the surface will be. In order to investigate the hydrophobic properties, silica nanoparticles, silica nanoparticles, and fly ash were prepared on concrete, and their properties were analyzed.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.256-256
• /
• 2011

Using plasmas, hydrophobic surfaces are made on various substances such as polyimide films, filter paper, cotton clothes and multi-walled carbon nanotube (MWCNT) with hexamethyldisiloxane (HMDSO), trimethylchlorosilane (TMCS) and toluene reagents. Plasmas are easily and rapidly to change surface of hydrophilic materials into hydrophobic. We have also optimized processing time and maximized contact angle for super-hydrophobicity of MWCNT. Contact angles have been calculated by measuring between substance and probe liquid, and total surface free energies are determined by the Owens-Wendt equation. Figure 1 shows the measured contact angles with time and ratio of reagents on MWCNT.

• Textile Coloration and Finishing
• /
• v.28 no.3
• /
• pp.156-163
• /
• 2016

The 6 novel super hydrophobic bluish-green dyes, showing the maximum absorption at 600~650nm, were synthesized to dye polyolefin fibers such as polypropylene and high strength polyethylene fibers. Their absorption spectra appeared almost the same at visible range, which meant the length of alkyl substituents did not affect on color appearance of the dyes. The optimum length of alkyl group was determined as hexyl substituents from the practical point of view. From the dyeing results, the optimum dyeing condition was $130^{\circ}C$ for 1 hour. The good fastness ratings to washing, rubbing were obtained showing 4-5 for both fibers. Light fastness was obtained also good rating 4 for both fibers.

• Textile Coloration and Finishing
• /
• v.21 no.6
• /
• pp.1-11
• /
• 2009

Super-hydrophobic surface, with a water contact angle greater than $150^{\circ}$, has a self cleaning effect termed 'lotus effect'. We introduced super-hydrophobicity onto aramid/rayon mixture fabric with dual-scale structure by assembling silica nano-sol. Mixture fabric was treated with silica nano-sol, fluoric polymer using various parameters such as particle size, concentration. Silica nano-sol size were measured using particle size analyzer. Morphological changes by particle size were observed using field emission scanning electron microscopy(FE-SEM), contact angle measurement equipment. The contact angle of water was about $134.0^{\circ}$, $137.0^{\circ}$, $143.0^{\circ}$, $139.5^{\circ}$ and $139.0^{\circ}$ for mixture fabric coated with 100.2nm, 313.7nm, 558.2nm, 628.5nm and 965.4nm silica nano-sol, compared with about $120.0^{\circ}$ for mixture fabric coated with fluoric polymer. When we mixed particle sizes of 100.2nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $146.2^{\circ}$. And we mixed particle sizes of 313.7nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $141.8^{\circ}$. Also we mixed particle sizes of 558.2nm and 965.4nm by 7:3 volume ratio, the best super-hydrophobicity was obtained. In this paper, we fabricated the water-repellent surfaces with various surface structures by using four types of silica nano-sol, and we found that the dual-scale structure was very important for the super-hydrophobicity.

• Textile Coloration and Finishing
• /
• v.21 no.1
• /
• pp.30-37
• /
• 2009

Studies on plants such as lotus leaf suggested that dual-scale structure could contribute to super-hydrophobicity. We introduced super-hydrophobicity onto poly(ethylene terephthalate)(PET) fabric with dual-scale structure by assembling $TiO_2$ nano sol. PET fabric was treated with $TiO_2$ sol, water-repellent agent using various parameters such as particle size, concentration. Morphological changes by particle size were observed using field emmission scanning electron microscopy(FE-SEM) and AFM measurement, contact angle measurement equipment. The contact angle of water was about 138.5$^{\circ}$, 125.8$^{\circ}$, 125.5$^{\circ}$ and 108.9$^{\circ}$ for PET fabric coated with 60.2nm, 120.1nm, 200nm and 410.5nm $TiO_2$ particles, compared with about 111.5$^{\circ}$ for PET fabric coated with water repellent. When we mixed particle sizes of 60.2nm and 120.1nm by 7:3 volume ratio, the contact angle of water was about 132.5$^{\circ}$. And we mixed particle sizes of 60.2nm and 200nm by 7:3 volume ratio, the contact angle of water was about 141.8$^{\circ}$. Also we mixed particle sizes of 60.2nm and 410.5nm by 7:3 volume ratio, the best super-hydrophobicity was obtained. In this paper, we fabricated various surface structures to the water-repellent surfaces by using four types of $TiO_2$ nano-particles, and we found that the nanoscale structure was very important for the super-hydrophobicity.

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2010.03a
• /
• pp.109-109
• /
• 2010

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2010.03a
• /
• pp.178-178
• /
• 2010

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.9 no.4
• /
• pp.469-477
• /
• 2021

In this study, the mechanical property of anti-fouling coating using CNF was evaluated to prevent the durability and stability of structure exposed the marine environment. Anti-fouling coating using CNF was prepared by CNF, AKD and waste glass powder, and contact angle test, drying time, viscosity analysis and microstructure were performed. When coating on one number of times, It was showed to relatively high hydrophobic performance in steel. And It was confirmed that the contact angle increased as the content of AKD increased in cement mortar. When coating on three number of times, the surface was confirmed super-hydrophobic at maximum of 151.6°. When mixing waste glass powder, the surface was showed to relatively high hydrophobic. It is pseudo plastic fluid when CNF and distilled water were prepared in a ratio of 1:1, And Anti fouling coating is judged to be suitable for use as coating on marine structure.

• Journal of the Korean Applied Science and Technology
• /
• v.34 no.1
• /
• pp.66-82
• /
• 2017

Organosilicone-based surfactants consist of hydrophobic organosilicone groups coupled to hydrophilic polar groups. Organosilicone surfactants have been widely used in many industrial fields starting from polyurethane foam to construction materials, cosmetics, paints & inks, agrochemicals, etc., because of their low surface tension, lubricity, spreading, water repellency and thermal and chemical stability, resulted from the unique properties of organosilicone. Especially, trisiloxane surfactants, having low molecular weight organosilicone as hydrophobe, exhibit low surface tension and excellent wettability and spreadability, leading to their applications as super wetter/super spreader, but have the disadvantage of vulnerability to hydrolysis. A variety of trisiloxane surfactant structures are required to provide the functional improvement and the defect resolution for reflecting the necessities in the various applications. This review covers the synthetic schemes of reactive trisiloxanes as hydrophobic siloxane backbones, the main reaction schemes, such as hydrosilylation reaction, for coupling reactive trisiloxanes to hydrophilic groups, and the synthetic schemes of the main trisiloxane surfactants including polyether-, carbohydrate-, gemini-, bolaform-, double trisiloxane-type surfactants.

• Journal of the Korean Applied Science and Technology
• /
• v.34 no.3
• /
• pp.461-477
• /
• 2017

Organosilicone-based surfactants, consisting of hydrophobic organosilicone groups coupled to hydrophilic polar groups, have been widely used in many industrial fields starting from polyurethane foam to construction materials, cosmetics, paints & inks, agrochemicals, etc., because of their low surface tension, lubricity, spreading, water repellency and thermal and chemical stability, resulted from the unique properties of organosilicone. Especially, organosiloxane surfactants, having low molecular weight siloxane as hydrophobe, exhibit low surface tension and excellent wettability and spreadability, leading to their applications as super wetter/super spreader, but have the disadvantage of vulnerability to hydrolysis. A variety of low molecular weight siloxane surfactant structures are required to provide the functional improvement and the defect resolution for reflecting the necessities in the various applications. This review includes the synthetic schemes of reactive tetrasiloxanes and disiloxanes as hydrophobic siloxane backbones, the main reaction schemes, such as hydrosilylation reaction, for coupling reactive tetrasiloxanes or disiloxanes to hydrophilic groups, and the main synthetic schemes of the tetra- and di-siloxane surfactants having polyether-, carbohydrate-, gemini-, bola-type surfactant structures.