• Transactions on Electrical and Electronic Materials
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• 제18권4호
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• pp.203-206
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• 2017

The effect of the content of microsilica and nanosilica continuously modified with hydroxy silane and epoxy-modified silicone in cycloaliphatic epoxy/microsilica/nanosilica composites (EMNCs) on the mechanical and water repellent properties was evaluated. Surface-modified micro- and nanosilica was well-mixed with a cycloaliphatic epoxy resin in the presence of polyester-modified polydimethylsiloxane (PEM-PDMS) as a dispersing agent using an ultrasonicator. Tensile and flexural tests were carried out using a universal testing machine (UTM). The water repellent property was evaluated by contact angle measurements of water on the composite surface. Tensile strength of the composite could be enhanced by 32.2% up to 91.4 MPa, and the flexural strength was raised to 122.0 MPa, which is 38.8% higher than that of neat epoxy. The contact angle of water on the composite was as high as $104.1^{\circ}$.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.76-77
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• 2021

compared and reviewed the water repellency and strength characteristics by controlling the surface stamping size and fine aggregate ratio of cement mortar mixed with water repellent as a method to control the ecological imitation surface structure. As a result of measuring the contact angle, the higher the ratio of fine aggregate, the larger the contact angle. The contact angle increased when the surface structure was changed by stamping, and increased as the stamping size became smaller. In the surface stamping of mesh#150, the contact angle was particularly increased.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.152.1-152.1
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• 2005

• 한국의류산업학회지
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• 제22권1호
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• pp.112-118
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• 2020

This paper examined the water repellency, water proofing and water vapor permeability of twelve types of woven fabrics for sports wear clothing. Their physical properties were compared and discussed with the fabric structural parameters and surface finishing effect. A water repellent property of 100% was obtained in the coated or laminated water repellent finished fabrics; in addition, cotton/nylon breathable composite fabrics treated with a laminated finishing and with low fabric density showed a 90% water repellency. Water proofing fabric above 6,000 mm H₂O hydraulic pressure was achieved by coated or laminated finishing; however, high density fabric or medium-level coated fabrics exhibited 100% water repellent and low water proofing characteristics. Superior water vapor permeability characteristics with good water repellency and proofing properties were achieved at the 2.5 layered low density and with 0.7 - 0.9 cover factor nylon fabrics treated with hydrophilic laminated finishing. The regression analysis for examining the effects of fabric structural parameters and surface finishing such as coating and laminating to the water vapor permeability exhibited a high determination coefficient of fabric structural parameters of 63.5%; in addition,, main factors among fabric structural parameters appeared to be cover factor and fabric thickness per weight. Coating and Laminating factors exhibited determination coefficient of water vapor permeability parameters of 36.5%.

• 대한가정학회지
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• 제20권3호
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• pp.19-24
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• 1982

This study was carried out to investigate the relationship between the water resistance and the air permeability. The results are as follows; 1. In case of the water proofing fabrics, We cannot find that there is any relationship between the water resistance and the air permeability according to the kinds of finishing, while in case of the water repellent finished fabries, we can find that there is a correlationship between them, especially the hydrostatic pressure and the air permeability are found to have negative correlation. 2. In case of the water proofing fabrics, the relationship between the water resistance and the air permeability is not affected by the thickness of the fabrics. On the other hand, in case of the water repellent finished fabrics, the relationship between them is affected by the thickness of the fabrics. Especially, the relationship between the hydrostatic pressure and the air permeability as well as the relationship between the water repellency and the air permeability is effect much by the thickness of the fabrics, too. 3. In case of the water proofing fabrics, the relationship between the water resistance and the air permeability is not affected by fabric count. On the otherhand, in case of the water repellent finished fabrics, the relationship between them is affected by the fabric count. Especially, the relationship between hydrostatic pressure and the air permeability, and the relationship between the water proof and the air permeability are affected much by fabric count.

• 보존과학연구
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• 통권22호
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• pp.133-154
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• 2001

Stone cultural properties, exposed in natural environment, is deteriorated by many weathering reasons for a long time. It is necessary to treat of consolidation and water-repellent on the surface because of the conservation of stone cultural properties. We was treated the specimen [granite(Hwangdung-suk), sandstone, marble(in JeongSeon)] by synthesis resin of DWR-Ⅲ, SI2121 and fluoropolymer, and tested on the durability, water-repellent, color stability and luster generation etc. In the result of this study, DWR-Ⅲ and fluoropolymer is superior to the waterrepellent, durability of salt and acid rain. SI2121 is superior to the penetration because of lower viscosity, but the water-repellent is inferior to the others. After the treatment of chemicals, the color-variation make an appearance but luster-generation doesn’t. With the passage of time, the color of specimen was got better because of the ‘washing’ phenomenon for ultra-violet, salt etc.

• Journal of Forest and Environmental Science
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• 제29권2호
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• pp.109-115
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• 2013

Fast-grown wood generally contains a high proportion of juvenile wood that results in inferior dimensional stability and durability against biological deteriorations. In the present research, the Acacia mangium wood from plantation forests in Vietnam was treated with high temperature in air. The effects of heat treatment on physical properties of Acacia mangium wood, including mass loss (ML), water absorption (WA), water-repellent effectiveness (WRE) and anti-swelling efficiency (ASE) were examined. The results showed that the dimensional stability and the water-repellent effectiveness are increased by about 15-46% and 8-18%, respectively. However, the mass and dimension of wood are decreased. The results also indicated that both treatment temperature and treatment duration significantly affect the wood properties of Acacia mangium. It is thus concluded that heat treatment demonstrates an interesting potential to improve the wood quality of Acacia mangium for solid timber products. This technology provides an environmentally safe method of protecting sustainable common woods to give a new generation of value-added biomaterials with increased stability without the use of toxic chemicals.

• 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.

• Korean Chemical Engineering Research
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• 제56권3호
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• pp.327-334
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• 2018

출발물질로서 테트라에톡시실란(TEOS)과 메틸트리메톡시실란(MTMS)을 사용하여 졸-겔법에 의해 발수성 코팅용액을 제조하였다. 이 용액을 냉연강판 위에 스핀 코팅하고 열처리하여 비불소계 발수 코팅 도막을 제조 하였다. 이 과정 중 MTMS/TEOS의 몰 비, 물 농도 및 암모니아 농도가 코팅 도막의 발수성에 미치는 영향을 연구하였다. MTMS/TEOS의 몰 비를 1~20으로 변화시켜 제조 한 코팅 도막의 접촉각은 MTMS/TEOS 몰 비가 10 일 때 최대 수치인 $108^{\circ}$를 나타내었다. 반면에 물의 첨가량을 증가시킴에 따라 코팅 도막의 접촉각이 증가하여 발수성이 향상되었다. 또한 암모니아의 첨가량이 커질수록실리카입자의 크기가커져 실리카입자의표면 거칠기가증가하므로 발수성이 증가하였다.

• 한국의류학회지
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• 제17권4호
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• pp.577-586
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• 1993

Pesticide protective clothing has not been frequently worn due to its lack of thermal comfort. It is important to develop fabrics which can allow the wearer to work in comfort. One of the possible way to achieve the goal is to produce fabrics with a water- and oil-repellent finish which would resist pesticide penetration but maintain some breathability. The purpose of this study were to evaluate the pesticide barrier properties of untreated and water- and oil-repellent finished nonwoven fabrics. Three types of nonwoven fabrics(Tyvek, Sontara and Kimlon) were used as test specimens. By pad-dry-cure method, each of the specimen was treated with fluorocarbon. The pesticide barrier properties (amount of pesticide penetration and residue) were measured by the gas chromatography. The performance properties of untreated and treated specimens were evaluated with respects to water pepellency(KS K 0590), oil repellency(AATCC 118), water resistance(KS K 0591, AATCC 42), water vapor transmission (KS A 1013) and air permeability(KS K 0570). The results of this study were as follows : 1) The untreated Sontara showed much more amount of pesticide penetration than untreated Tyvek and Kimlon, while the treated Sontara showed little amount of pesticide penetration. 2) After laundering, the amount of pesticide residue in the untreated and treated Sontara was less than that in Tyvek and in Kimlon. 3) Water- and oil-repellent finish improved water repellency, oil repellency, and water resistance of specimens. 4) The untreated Sontara and Kimlon showed higher water vapor transmission and air permeability than untreated Tyvek. Water vapor transmission and air permeability of treated specimen decreased compared to those of untreated.