• Elastomers and Composites
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• v.50 no.1
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• pp.35-48
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• 2015

Polyhedral oligomeric silsesquioxane (POSS) is an important inorganic-organic hybrid material with a three-dimensional structure. Polyurethane (PU) is a widely applied polymer that has versatile properties with the change of two phase structure. When POSS is incorporated into PU by physical or chemical methods, many properties can be greatly improved, such as mechanical properties, thermal stability, biodegradation resistance, and water resistance. This paper reviews the recent progress in preparation, structure, and performance of POSS-modified polyurethane from the viewpoint of physical blending and chemical modification.

• Journal of the Korean Ceramic Society
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• v.42 no.10 s.281
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• pp.645-648
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• 2005

To fabricate a (100) silicon hard master, we used anisotropic wet etching for the embossing. The etching chemical for the sili­con wafer was a TMAH 25$\%$ solution. The anisotropic wet etching produces a smooth sidewall surface inclined at 54.7°, and the surface roughness of the fabricated master is about 1 nm. After spin coating an organic-inorganic sol-gel hybrid resin on a silicon substrate, we used the fabricated master to form patterns on the silicon substrate. Thus, we successfully obtained patterns via the hot embossing technique with the (100) silicon hard master. Moreover, by using a single hydrophobic surface treatment of the master, we succeeded in achieving uniform surface roughness of the embossed patterns for more than ten embossments.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.289-289
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• 2011

The conducting polymer thin films were deposited using the gas phase method which known as molecular layer deposition (MLD). Terephthalaldehyde (TPA) and p-phenylenediamine (PD) were used as monomers to deposit conducting polymer. Self-terminating nature of TPA and PD reaction were demonstrated by growth rate saturation versus precursors dosing time. Infrared spectroscopic and X-ray photoelectron spectroscopy were employed to determine the chemical composition and state of conducting polymer thin films. Layer by layer growth and polymerization of thin films can be showed by shifting of absorption edge using UV-VIS spectroscopy. This conducting polymer fabricated by using MLD method gives the opportunity to develop new hybrid materials by combining inorganic materials in nanoscale.

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.164-164
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• 2008

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.587-592
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• 2006

코팅은 플라스틱의 표면의 물성과 렌즈의 광학적 성능을 높이기 위해 필요하다. Allyl diglycol carbonate계열 렌즈 표면의 물성과 광학적 성능을 개선하기 위하여 3-glycidoxypropyltrimethoxysilane(GPTS), methyltrimethoxysilane(MTMS) 및 tetraethyl orthosilicate(TEOS)의 몰 비를 변화시켜 유-무기 하이브리드 재료로 사용하였다. Sol-gel 공정에 의한 flow코팅하여, $140^{\circ}C$에서 4시간 경화하였다. 코팅 렌즈는 투과율, 부착력, 연필경도, 내마모성, 내온수성 및 내약품성을 평가하였고 GPTS, MTMS 및 TEOS의 몰비가 각각 1: 1: 2일 때 가장 우수한 것으로 나타났다.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.313-316
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• 2006

눈은 자외선과 가시광선에 노출되어 있다. 눈은 자외선 노출에 해로우므로 모든 자외선으로부터 눈을 보호해야 한다. 본 연구에서는 자외선 차단을 위해 투명 플라스틱에 유-무기 하이브리드 재료와 자외선 흡수제의 배합에 의한 자외선 차단 코팅하였고, PMMA, CR 39 및 PC기재에 적용하여 자외선 차단 효과를 조사하였다. 자외선 흡수제의 양이 증가할수록 자외선의 투과도는 낮았다. PMMA의 경우 자외선 투과도를 현저히 감소시켰으며 CR 39에서도 자외선 차단 효과가 있는 것으로 나타났다. 한편, PC자체에서는 자외선 차단효과가 있는 것으로 평가되었다. CR 39 렌즈의 부착력, 내약품성, 내온수성은 우수하였고, 연필 경도의 경우 4H였으며 내마모성은 좋지 않았다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.10a
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• pp.152-152
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• 2009

유기태양전지 Solvent인 1-2-Dichlorobenzene(DCB)에 1-Bromonaphtalene(BN)을 첨가하여 Air분위기에서 ZnO film을 이용한 유/무기 복합 태양전지를 만들었다. 셀의 구조는 ITO/ZnO nanofilm/Poly(3-hexylthiophene(P3HT):[6,6]-Phenyl C60-Butyric acid methyl ester(PCBM)/PEDOT:PSS/Ag로 제작했다. 두께 70nm ZnO film은 전기화학적 방법으로 ITO위에 전착하였다. AM1.5조건에서 Solar simulator로 측정한 결과 BN을 첨가한 셀에서 Jsc값이 증가되었다. Jsc값의 증가는 BN이 결정화를 향상시켜 효율이 증가됨을 확인하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.268-268
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• 2012

합금도금강판의 일시 방청과 기능성 부여 후처리는 크로메이트, 인산염처리 등과 같은 방법을 시행하는 것이 일반적이다. 그러나, 최근에는 아연합금도금 강판의 사용 및 보관 환경이 가혹해짐에 따라 보다 우수한 일시 방청성과 내식성이 요구되고 있다. 본 연구는 tetraethoxysilane (TEOS), methacryloxypropyltrimethoxysilane (MPTMS) 무기성분과 multifuncitional trimethylolpanetriacrylate(TMPTA) 그리고 1,6-Hexanediol diacrylate(HDODA) 등의 유기성분을 갖는 유무기 하이브리드 솔젤(sol-gel)1)을 제작하여 각 조건에 대하여 표면 관찰 및 염수분무시험을 통한 내식성 평가를 진행하였다.

• Electronic Materials Letters
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• v.14 no.6
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• pp.657-668
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• 2018

Organic-inorganic hybrid lead halide perovskites have been extensively investigated for various optoelectronic applications. Particularly, owing to their ability to form highly crystalline and homogeneous films utilizing low-temperature solution processes (< $150^{\circ}C$), perovskites have become promising photoactive materials for realizing high-performance flexible solar cells. However, the current use of mesoporous $TiO_2$ scaff olds, which require high-temperature sintering processes (> $400^{\circ}C$), has limited the fabrication of perovskite solar cells on flexible substrates. Therefore, the development of a low-temperature processable charge-transporting layer has emerged as an urgent task for achieving flexible perovskite solar cells. This review summarizes the recent progress in low-temperature processable electron- and hole-transporting layer materials, which contribute to improved device performance in flexible perovskite solar cells.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1366-1370
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• 2001

Thin films of the SiO2-TiO2-PDMS composite material have been prepared by the sol-gel dip coating method. Acid catalyzed solutions of tetraethoxy silane (TEOS) and polydimethyl siloxane (PDMS) mixed with titanium isopropoxide Ti(OiPr) were used as precursors. The optical and structural properties of the organically modified 70SiO2-30TiO2 composite films have been investigated with Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible Spectroscopy (UV-Vis), Differential Thermal Analysis (DTA) and prism coupling technique. The films coated on the soda-lime-silicate glass exhibit 450-750 nm thickness, 1.56-1.68 refractive index and 88-94% transmittance depending on the experimental parameters such as amount of PDMS, thermal treatment and heating rate. The optical loss of prepared composite film was measured to be about 0.34 dB/cm.