• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.360-360
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• 2011

We demonstrated the fabrication method of superhydrophobic nanocoating through a facile spin-coating and the chemical modification. The resulting coating showed a tremendous water repellency with a static water contact angle (CA) of 158$^{\circ}$ and a hysteresis of 1$^{\circ}$. The number of ZnO nanoparticle (NP) coating cycles affected on the surface roughness, which is key role for superhydrophobic surface, and thus the CA can be modulated by changing the ZnO NP coating cycles. The CA can be controlled by changing the carbon length of Self-Assembled Monolayers(SAM). This simple ZnO coating is substrate-independent including flexible surfaces, papers and cotton fabrics, which can effectively be used in various potential applications. We also observed the thermal and dynamic stabilities of SAM on ZnO nanoparticles. The superhydrophobicic surface maintained its superhydrophobic properties below 250$^{\circ}C$ and under dynamic conditions.

• 한국응용과학기술학회지
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• 제36권2호
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• pp.531-540
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• 2019

친수성 및 소수성 나노실리카를 tetraethyl orthosilicate(TEOS)를 커플링제로 사용하여 유리 표면에 거친 스파이크 구조 형성과 반응성 hydroxyl기를 동시에 도입한 후 불소를 함유한 실란으로 2차 코팅처리하여 궁극적으로 발수성 유리 표면 형성의 최적 조건을 확립하는 연구를 수행하였다. 소수성 나노실리카인 실리카 에어로졸을 이용한 초소수 도막의 형성은 나노실리카 표면에 반응성인 -OH기가 존재하지 않아 내구성이 있는 소수성 도막을 형성할 수 없었다. 이에 반하여 친수성기를 가진 나노실리카와 가수분해된 TEOS를 포함하는 코팅액 이용하여 유리 표면을 1차 코팅한 후 2차로 trichloro-(1H,1H,2H,2H)perfluorooctylsilane(TPFOS) 용액으로 코팅하여 $150^{\circ}$ 이상의 수접촉각을 가지는 초소수 표면을 제조하였으며, $1^{\circ}$ 이하의 물 슬라이딩각을 보여 초발수성도 동시에 가지고 있었다. 이에 덧붙여 친수성 나노실리카의 함량이 증가할수록 광투과도가 감소하였으며, TPFOS 용액에 의해서도 광투과도가 감소하였다. 코팅된 유리시편의 내구성 50회 문지름까지는 초소수성을 유지하였으나, 200회 문지름에서는 단지 소수성만을 유지하였다. 결론적으로 최적의 코팅액의 조건은 친수성 나노실리카의 함량이 0.3 g인 HP3 코팅액을 2회 코팅한 후 2차로 TPFOS 용액으로 코팅하는 것이었다. 이렇게 제조된 코팅액은 광투과도가 중요한 솔라셀의 표면 처리제로 사용이 가능할 것으로 판단된다.

• Macromolecular Research
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• 제17권9호
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• pp.666-671
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• 2009

Water repellent elastomeric surfaces were fabricated successfully on SBS/MWNT nanocomposites films using the breath figure method and subsequent thermal treatment. The uniformly dispersed CNTs were found to play significant roles in tuning the size and ordering of the macroporous morphology at the nanocomposite surface as well as enhancing the mechanical properties of nanocomposites. In particular, the CNTs dispersed in a nanocomposite solution retarded the coarsening process of aqueous droplets during the breath figure process and decreased the pore size in the finally fabricated film. The water contact angle measurement showed that the double-scale structure comprised of self-organized macropores and surface the roughness induced by a thermal treatment produced a highly water-repellent nanocomposite surface.

• 한국세라믹학회지
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• 제37권8호
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• pp.760-767
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• 2000

Recently, the protection of construction is demanded with environmental pollution. These protect modes are use of concrete admixture, coat of protective polymer and impregnate of surface with chemicals etc. The most widely used impregnation is economical and effective. The define of Impregnation for construction protect is reacted in and consolidated substrate after absorbed. The impregnation agents are Polyesters, Acrylic monomers, Epoxy and Silicone derivatives. Commonly, because the Silane has good water repellency and environmental advantages that it widely used to water proofing agents, dampproofing agents and absorption reducer for concrete of bridges. When application of Silane, it occurs pollution and harmfulness as included organic solvent. The manufactures have tired to emulsification of Silane for the reducing of the defects. The Silane emulsion is vary unstable and does not stored long periods, and it is diminished in good properties with internal reaction. In this study we tried to emulsification of Silane for effectiveness improvement and reduce pollution and hazard and discussed properties variation of emulsion. The Silane emulsions are achieved emulsifying with W/O and O/W type surfactants. It used 0.24% PVA as protective colloid and stable phase is creamy. The creamy Silane emulsion performance as the penetration depth and water absorption rate are above 4 mm and below 0.1. It stable about 6 month at room temperature.

• Corrosion Science and Technology
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• 제20권5호
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• pp.256-265
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• 2021

Titanium is applied in various industries due to its valuable properties and abundant reserves. Generally, if a highly uniform oxide structure and a high-density oxide film is formed on the surface through anodization treatment, the utility value such as color appearance and corrosion inhibition efficiency is further increased. The objective of this study was to determine improvement of water-repellent property by controlling titanium oxide parameters such as pore size and inter-pore distance to improve corrosion resistance. Oxide film structures of different shapes were prepared by controlling the anodization processing time and voltage. These oxide structures were then analyzed using a Field Emission Scanning Electron Microscope (FE-SEM). Afterwards, a Self-Assembled Monolayer (SAM) coating was performed for the oxide structure. The contact angle was measured to determine the relationship between the shape of the oxide film and the water-repellency. The smaller the solid fraction of the surface, the higher the water-repellent effect. The surface with excellent hydrophobic properties showed improved corrosion resistance. Such water-repellent surface has various applications. It is not only useful for corrosion prevention, but also useful for self-cleaning. In addition, a hydrophobic titanium may open up a new world of biomaterials to remove bacteria from the surface.

• 한국염색가공학회지
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• 제17권6호
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• pp.27-35
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• 2005

Conventional pad- dry-cure(thermo-fixation) process usually produces functional performance on both sides of a fabric. UV curing technique was applied to impart water- and oil-repellent finish effective only on the face of a PET knitted fabric. The preferential one-side coating, by virtue of the limited penetration of UV light, was achieved by W curing after padding of a fluorocarbon agent without special coating or printing equipments. The difference in the functional property of face and back sides was examined by measuring water and oil repellency at each side of the treated fabric. The influence of pre/post-irradiation dose and agent concentration on the performance of the finished fabrics were investigated. While increase in both resin concentration and post-irradiation did not have significant effect on the finish, UV pre-irradiation of PET fabrics caused remarkable influence presumably due to appropriate surface modification of PET fabrics required for facile wetting of the resin. The dimensional stability and color change of the UV cured fabrics measured by FAST and reflectance spectrophotometry showed significantly decreased color difference and increased percent extension compared with the samples pre-irradiated without agent application.

• 한국표면공학회지
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• 제54권2호
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• pp.90-95
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• 2021

Surface modification technique enabling the control of condensation provides various benefit in various engineering systems, such as heat transfer, desalination, power plants, and so on. In this study, lubricant oil-impregnation into Teflon-coated nanoporous anodic oxide layer of aluminum to enhance a de-wetting and mobility of water droplet on surface. Due to the surface treatment improving water-repellency, the condensation mode is changed to dropwise, thus the frequency of sliding condensed water droplet on surface is increased. For these reasons, the surface of oil-impregnated Teflon-coated nanoporous anodic aluminum oxide shows significantly enhanced condensation heat transfer compared to bare aluminum surface. In addition, the porosity of anodic aluminum oxide affected the mobility of water droplet even with oil-impregnation and Teflon-coating, indicating that the optimization of porous structure of anodic oxide is required for maximizing the condensation heat transfer.

• 한국의류학회지
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• 제30권3호
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• pp.481-486
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• 2006

한지를 의류용으로 사용하기 위한 시도들이 있었지만, 습윤상태에서 물리적 성질이 크게 감소한다는 문제점 때문에 많은 한계를 가지고 있었다. 따라서 한지의 습윤상태에서의 물리적 성질을 향상시키기 위해 내수성을 부여하고자, 실리콘 수지를 이용하여 한지에 발수가공을 행하였다. 패드-드라이-큐어 방법을 사용하여 처리하였고, 가공의 최적조건을 알아보기 위해 수지의 농도와 촉매의 농도, 큐어링 시간과 온도를 변화시켜 실험하였다. 한지의 발수도, 강연도, 방추도를 측정하였고, 습윤과 건조상태에서의 인장강도, 인열저항 마찰저항을 비교하였다. 그 결과 한지의 발수가공을 위한 최적처리조건은 실리콘 수지농도 40g/l, 촉매농도는 수지농도의 1/2인 20g/l, 큐어링 온도 160$^{circ}C$, 큐어링 시간 120초였다. 가공 후에도 한지의 유연성은 크게 저하되지 않았으며, 방추도는 약간 증가하였다. 가공 후, 건조상태에서의 인장강도, 인열저항은 큰 변화가 없었으나 내마모도는 증가하였고, 습윤상태에서의 인장강도, 인열저항, 내마모도 모두 증가하였다.

• 펄프종이기술
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• 제35권3호
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• pp.43-52
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• 2003

The new principle to measure a sizing degree by a contact angle was developed using an automatic determination of the 3-end point coordinates of the water droplet on a sheet, which could diminish the operator's bias during measurement. A constant amount of water was first placed on a sample sheet by a water dispenser, and then an image of the liquid droplet was captured by a digital camera and then transmitted to a computer. The program measuring for contact angle extracted a liquid contour by Gaussian function combined with a 8-direction chain code. The Euclidean equation was applied to the binary image of the liquid contour in order to measure the diameter of the contour. Finally, the contact angle of the liquid was calculated by using the diameter and the top coordinates. In addition, a surface free energy of the sample sheet and an elapsed time taken up to the complete absorption into the sheet were simultaneously measured with the contact angle.

• 한국건축시공학회지
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• 제15권6호
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• pp.607-614
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• 2015

일반적으로 건축물의 마감은 기본적인 발수성을 가진 수성페인트 마감으로 이루어진다. 이는 건축물 외벽에 작업시 적용하기 쉬우며, 건축물 유지 또한 쉬워 많은 장점을 가지고 있다. 하지만 자외선으로 인해 변색 또는 열화 되기 쉬워 그 효과는 기대에 미치지 못하고 있다. 따라서 본 연구는 외부 표면마감 재료로서 발수제를 직접 혼입한 수성페인트의 색 변화를 통한 내구성능을 분석하여 실제 현장에 적용하기 위한 실용성을 평가하고자 하였다. 촉진 시간에 따른 색 변화 및 색차를 측정하였으며, 적용가능성은 실험결과를 토대로 평가하였다. 색차, 명도 및 색도의 변화량을 실험결과에 따라 종합적으로 고려해 볼 때 본 연구에서 제안한 발수제를 혼입한 수성페인트 마감공법(혼입율 2, 5, 8%)은 충분히 사용 가능할 것으로 사료된다. 이는 건축물의 외부 표면을 수성페인트로 칠한 후 추가로 발수제를 도포하는 등의 기존 표면 마감방법에 비해 공사내용이 간편하며 시공성도 양호하여 폭넓은 활용이 기대된다. 또한 실제 현장에서는 원하는 색상으로 필요한 양만큼 제조하여 사용할 수 있으며, 전문 인력이 필요하지 않아 손쉽게 활용 가능할 것으로 기대된다.