• 제목/요약/키워드: Hybrid gel

검색결과 251건 처리시간 0.027초

졸-겔법에 의한 안경렌즈의 열경화형 유-무기 하이브리드 코팅 (Thermally Curable Organic-inorganic Hybrid Coatings on Ophthalmic Lenses by the Sol-Gel Method)

  • 유동식;이지호;하진욱
    • 한국산학기술학회논문지
    • /
    • 제7권3호
    • /
    • pp.465-470
    • /
    • 2006
  • 코팅은 플라스틱의 표면의 물성과 렌즈의 광학적 성능을 높이기 위해 필요하다. Allyl diglycol carbonate계열 렌즈의 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 몰 비가 각각 1:1:2일 때 가장 우수한 것으로 나타났다.

  • PDF

Effect of Heat Treatment on the Morphology and Transparency of Thick Inorganic-Organic Hybrid Films Prepared by the Electrophoretic Sol-Gel Deposition of Polyphenylsilsesquioxane Particles

  • Hasegawa, Koichi;Katagiri, Kiyofumi;Matsuda, Astunori;Tatsumisago, Masahiro;Minami, Tsutomu
    • The Korean Journal of Ceramics
    • /
    • 제6권1호
    • /
    • pp.15-20
    • /
    • 2000
  • Thick inorganic-organic hybrid films were prepared on ITO-coated glass substrates by the electrophoretic sol-gel deposition of polyphenylsilsesquioxane particles. The morphology of the deposited films changed from the aggregate of the spherical particles to monolith by heat treatment at temperatures higher than $200^{\circ}C$. Transparency of the films was significantly improved accompanied by the morphological change of the particles. The degree of the morphological change was governed by two factors; maximum heat treatment temperature and heating rate. Transparent thick films of ca. 3$\mu\textrm{m}$ in thickness were obtained only by heat treatment at $400^{\circ}C$ for 2h with rapid heating from room temperature to $400^{\circ}C$. These films obtained were strongly adhered to the ITO-coated glass substrates and has a very smooth surface.

  • PDF

Enhanced Corrosion Protection Performance by Novel Inhibitor-Loaded Hybrid Sol-Gel Coatings on Mild Steel in 3.5% NaCl Medium

  • Suleiman, Rami K.
    • Corrosion Science and Technology
    • /
    • 제18권5호
    • /
    • pp.168-174
    • /
    • 2019
  • The sol-gel methodology has been applied successfully in the synthesis of a novel hybrid coating based on dimethoxymethyl-n-octadecylsilane precursor. The newly synthesized parent coating was functionalized further with two commercially-available corrosion-inhibitive pigments Moly-$white^{(R)}$ 101-ED and Hfucophos $Zapp^{(R)}$, applied to mild steel panels, and immersed continuously in 3.5% NaCl electrolytic solution for 288 h. The corrosion protection performance of the prepared functional coatings was evaluated using electrochemical impedance spectroscopy (EIS) and DC polarization techniques. An enhancement in the barrier properties has been revealed from the electrochemical characterization data of the hybrid films, in comparison with untreated mild steel substrates following long-term immersion in 3.5% NaCl. The corrosion resistance properties of the newly developed coatings over mild steel substrates found to be largely dependent on the type of the loaded inhibitive pigment in which the Moly-white inhibitor has a positive impact on the corrosion protection performance of the parent coating, while an opposite behavior was observed upon mixing the base polymeric matrix with the commercially-available Zapp corrosion inhibitor.

Adhesion Reliability Enhancement of Silicon/Epoxy/Polyimide Interfaces for Flexible Electronics

  • Kim, Sanwi;Kim, Taek-Soo
    • 마이크로전자및패키징학회지
    • /
    • 제19권3호
    • /
    • pp.63-69
    • /
    • 2012
  • Adhesion and mechanical reliability of silicon/epoxy/polyimide interfaces are critical issues for flexible electronics. Bonds between these interfaces are mainly hydrogen bonds, so their adhesion is weaker than cohesive fracture toughness and vulnerable to moisture. In order to enhance adhesion and suppress moisture-assisted debonding, UV/Ozone treatment and innovative sol-gel derived hybrid layers were applied to silicon/epoxy/polyimide interfaces. The fracture energy and subcritical crack growth rate were measured by using a double cantilever beam (DCB) fracture mechanics test. Results showed that UV/Ozone treatment increased the adhesion, but was not effective for improving reliability against humidity. However, by applying sol-gel derived hybrid layers, adhesion increase as well as suppresion of moisture-assisted cracking were achieved.

제작조건에 따른 졸-겔 복합 실리카 박막의 광학적 성질 변화 (The influence of preparation condition on optical property of sol-gel derived hybrid organic-inorganic silica glass thin films)

  • 정재완
    • 한국광학회지
    • /
    • 제11권4호
    • /
    • pp.255-260
    • /
    • 2000
  • 유기 금속화합물을 출발물질로 이용하는 졸-겔 방법으로 균열이 없는 유기-무기 복합 실리카 박막을 제작하였으며, 코팅방법, 조성비, prebake, postbake 온도 등의 제작조건에 따른 박막의 두께 및 굴절률의 변화를 체계적으로 조사하여 재현성 있는 제작조건을 확립하였다. 특히 광개시제를 첨가하였을 때 자외선 노광량에 따른 광학적 성질변화를 세 가지 광개시제에 대하여 측정, 비교하였다. 또한 졸-겔 박막으로 다중모드 간섭을 이용한 광 파워 분배기를 제작하여 광소자로의 응용 가능성을 살펴보았다.

  • PDF

무편광 Hybrid Sol-Gel 배열도파로 격자 소자의 설계 및 제작 (Polarization-Insensitive Design and Fabrication of Hybrid Sol-Gel Arrayed Waveguide Gratings)

  • 박순룡;정재완;오범환;이승걸;이일항
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
    • /
    • pp.105-108
    • /
    • 2002
  • We report on the polarization-insensitive design and fabrication of an arrayed waveguide gratings (AWG's) using sol-gel derived silica glass films formed on fused silica substrates to provide cheap and stable tools for better design. An arrayed-waveguide grating multiplexer with raised structure is fabricated in order to effect polarization sensitivity. Since polarization is usually not known after propagation in an optical fiber. passive WDM components such as monolithic wavelength demultiplexer have to be polarization insensitive. Here, we observed that polarization have effect on crosstalk of output spectrum in arrayed-waveguide grating

  • PDF

Inorganic-organic Hybrid Proton Conductive Membranes Doped with Phosphoric Acid

  • Huang Sheng-Jian;Lee Yong Su;Lee Hoi Kwn;Kang Won Ho
    • 한국산학기술학회:학술대회논문집
    • /
    • 한국산학기술학회 2004년도 춘계학술대회
    • /
    • pp.96-99
    • /
    • 2004
  • A new proton conductive inorganic-organic hybrid membrane doped with $H_3PO_4$ was fabricated via sol-gel process wit 3- glycidoxypropyltrimethoxysilane(GPTMS), 3-aminopropyltriethoxysilane(APTES) and tetraethoxysilane(TEOS) asprecursors. Theproto conductivity of about 3.0$\times10^{-3}S/cm$ was obtained at $120^{\circ}C$ under $50\%$ relative humidity (R.H). DTA curves showed that the thermal stability of the membrane is significantly enhanced by the presence of $SiO_2$ framework up to $250^{\circ}C$. SEM and XRD revealed that the gel is microporou and amorphous. The addition of APTES improved the conductivity of the membranes and the effect of the APTES on the conductivity was also discussed in this paper.

  • PDF

Large Band Gap Attenuation of CdS Nanoclusters after H2S Exposure

  • Han, Seung-Woo;Park, Eun-Hye;Kang, Kwang-Sun
    • Current Photovoltaic Research
    • /
    • 제7권2호
    • /
    • pp.29-32
    • /
    • 2019
  • Large band gap attenuation of CdS nanoclusters in hybrid sol gel matrix comprised of 3-(trimethoxysilyl)propyl methacrylate (TMSPM), 15 wt. % zirconium, and various amounts of cadmium acetate was observed after $H_2S$ exposure. Hybrid sol gel matrixes were prepared by hydrolysis and condensation reactions. The sol gels contained with various amount of cadmium acetate were spin coated to glass substrates and exposed to $H_2S$ gas. The UV-visible absorption peaks were shifted toward blue with increasing the amount of CdS nanoclusters and were shifted to the red after thermal process. Significant amount of -OH absorption peaks were reduced after thermal process. Strong room temperature photoluminescence (PL) of CdS nanoclusters was observed after exposing to $H_2S$ gas. The PL intensity increased for several minutes and slowly decreased thereafter. The luminescence peaks were continuously shifted toward blue as the time passed. Extraordinary Stokes shift (approximately 160 nm) was observed.

졸-겔법을 이용하여 알콕사이드 전구체로부터 합성된 Polyimide-silica 혼성체의 특성 (Characteristics of Polyimide-silica Hybrid Materials Prepared from Alkoxide Precursor Using Sol-gel Process)

  • 김병우;이성환;김성완;박재현;김준호;박성수;박희찬
    • 한국세라믹학회지
    • /
    • 제39권11호
    • /
    • pp.1063-1068
    • /
    • 2002
  • Polyimide와 silica에 물리적 또는 화학적으로 결합된 Polyimide/silica(PI/silica) 혼성체들을 졸-겔법을 통하여 Polyamic Acid(PAA) 또는 end-capped PAA 용액에 tetraethoxysilane을 가수 분해 및 축 중합시켜서 제조하였다. PAA 용액은 dimethylacetamide 용액 내에서 pyromellitic dianhydride와 oxydianiline 단량체들을 개환 반응으로 합성하였다. End-capped PAA 용액은 PAA 용액에 3-aminopropyltriethoxysilane을 첨가하여 제조하였다. 적외선 분광기, 시차 열분석기, X-선 회절 분석기, 주사 전자현미경 및 인장 강도 시험기를 통하여 PI/silica 혼성체 시편들의 특성을 분석하였다. 혼성체 시편들의 물성은 PI와 silica간의 결합형 및 silica의 함량에 의해 영향을 받는다는 것을 확인하였다.

전기방사에 의한 Titania-Silica 혼성 섬유의 제조 및 특성분석 (Preparation and Characterization of Titania-Silica Hybrid Fibers by Electrospinning)

  • Park, Sung-Seen;Lee, Seung-Goo;Joo, Chang-Whan
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 2003년도 봄 학술발표회 논문집
    • /
    • pp.386-387
    • /
    • 2003
  • Titania-silica hybrid inorganic materials are interesting subjects and many researchers have been studying.$\^$1-3)/ In general, the titania-silica hybrid materials are used as film and catalyst. Sol-gel method has widely been used as an alternative technology to prepare a wide variety of applications including monoliths, powders, coatings, and fibers.$\^$4-6)/ The typical sol-gel method is hydrolysis and condensation of tetraethyl orthosilicate (TEOS), Si(OCH$_2$CH$_3$)$_4$. (omitted)

  • PDF