• Title/Summary/Keyword: gel materials

Search Result 1,727, Processing Time 0.027 seconds

Properties of Nano-Hybrid Coating Films Synthesized from Colloidal Silica-Silane (콜로이달 실리카와 실란으로부터 합성된 나노하이브리드 코팅 박막의 특성)

  • Na, Moon-Kyong;Ahn, Myeong-Sang;Kang, Dong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2006.06a
    • /
    • pp.232-233
    • /
    • 2006
  • In recent years the interest in organic/inorganic hybrid materials has increased at a fast rate. Nano organic-inorganic hybrid composites have shown advantages for preparing hard coating layers. Especially, nano hybrid composite has low environmental pollution. It has high transparency, hardness, toughness, thermal dissociation temperature, hydrophobicity by using nano sized inorganic material. There are many ways in which these materials may be synthesized, a typical one being the use of silica and silanes using the sol-gel process. The structure of sol-gel silica evolves as a result of these successive hydrolysis and condensation reactions and the subsequent drying and curing. The sol-gel reactions are catalyzed by acids and produce silica sol solutions. The silica sol grows until they reach a size where a gel transition occurs and a solid-like gel is formed. Colloidal silica(CS)/silane sol solutions were synthesized in variation with parameters such as different acidity and reaction time. In order to understand their physical and chemical properties, sol-gel coating films were fabricated on glass. From all sol-gel solutions, seasoning effect of sol-gel coating layer on glass was observed.

  • PDF

Transparent Sol-Gel Hybrid Dielectric Material Coatings for Low k Passivation Layer

  • Yang, Seung-Cheol;Oh, Ji-Hoon;Kwak, Seung-Yeon;Bae, Byeong-Soo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.1453-1456
    • /
    • 2009
  • Transparent sol-gel hybrid dielectric material (hybrimer) coating films were fabricated by spin coating and photo or thermal curing of sol-gel derived oligosiloxane resins. Hybrimer coating films are suitable as the passivation layer of TFT in AMLCD due to low dielectric constant, small loss tangent, low leakage current density, high transmittance and thermal stability.

  • PDF

Synthesis of Silicon Carbide Nanowhiskers from Coconut Fibres and Sol-Gel Derived Silica

  • Raman, V.;Bhatia, G.;Mishra, A.;Saha, M.;Sengupta, P.R.;Srivastava, A.K.
    • Carbon letters
    • /
    • v.7 no.3
    • /
    • pp.166-170
    • /
    • 2006
  • Silicon carbide whiskers ($SiC_w$) having the diameter in the range of 20-80 nm were synthesised from coconut fibres through sol-gel process. The coconut fibres were impregnated with tetraethoxysilane and methyltriethoxysilane derived sol and pyrolyzed at $1400^{\circ}C$ in argon. X-ray of the pyrolyzed samples showed the formation of ${\beta}$-SiC.

  • PDF

Synthesis of ZrO2 Gel Dispersed with Au Fine Particles by Sol-Gel Method (졸-겔법에 의한 Au 미립자 분산 ZrO2 겔의 합성)

  • Mun, Chong-Soo;Lee, Seung-Min
    • Korean Journal of Materials Research
    • /
    • v.13 no.4
    • /
    • pp.219-223
    • /
    • 2003
  • Zirconia gels dispersed with fine Au particles have been prepared by the sol-gel method. Starting solution with (OC$Zr_4$$H_{ 9}$)$_4$, $C_4$ $H_{9}$ OH, $H_2$O,$ HNO_3$, $HAuC1_4$ was used to prepare gels in several molar ratio. After hydrolysis, viscosity of solutions as 4∼5 cP and gelling time of sols were spent about 9 days. As the heat-treatment temperature was increased,$ ZrO_2$ had the phase transition from tetragonal to monoclinic at $750^{\circ}C$. Heat-treatments of the gel have performed at 500, 700, 750, 800, 1000 and $1100^{\circ}C$ for 3 hrs, respectively. We have investigated TG-DTA, X-ray diffraction patterns, SEM and EDS. The size of Au fine particles dispersed in the heat-treatmented gel was about 0.15∼0.23 $\mu\textrm{m}$ and the shape was most sphericity.