• Bulletin of the Korean Chemical Society
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• 제27권3호
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• pp.399-402
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• 2006

Porous organic-inorganic hybrids have been prepared from tetraethylorthosilicate (TEOS) and organosilane precursors by sol-gel method. Two organosilanes, 3-(2,4-dinitrophenylamino)propyltriethoxysilane (DNPTES) and N-[[(2-nitrophenyl)methoxy]carbonyl]-3-triethoxysilylpropylamine (NPTES) were used to incorporate electron-accepting (di)nitrophenyl groups into the hybrids. The hybrids were characterized by FT-IR spectroscopy and elemental analysis, and their pore characteristics were studied by nitrogen sorption porosimetry. Surface area of the hybrids ranged from 563 to 770 $m^2$/g, pore volume, 0.23-0.30 $cm^3$/g, and porosity, 35-41%. It was demonstrated by UV-vis spectroscopy that aniline, ethylenediamine, and 1-aminonaphthalene could be removed from their hexane solutions in the presence of the hybrid powders. The removal of amines is attributable to donor-acceptor interaction between the electron-donating amines and electron-accepting (di)nitrophenyl moiety.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.869-874
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• 2006

We have carried out the Glaser oxidative coupling polymerizations of diethynyldiphenylsilane, diethynylmethylphenylsilane,diethynylmethyloctylsilane, and 1,2-diethynyl-1,1,2,2-tetramethyldisilane to afford polycarbosilanes containing diethynyl and organosilane groups in the main chain, such as poly(diethynyldiphenylsilane), poly(diethynylmethylphenylsilane), poly(diethynylmethyloctylsilane), and poly(1,2-diethynyl-1,1,2,2-tetramethyldisilane), respectively. These obtained materials are almost insoluble in common organic solvents such as $CHCl_3$ and THF probably due to the presence of a rigid rod diacetylene group along the polymer main chain. Therefore, the polymers were characterized using several spectroscopic methods in solid state. FTIR spectra of all the polymeric materials show that the characteristic $C \equiv C$ stretching frequencies appear at 2147-2154 $cm ^{-1}$, in particular. The polymers in the solid state exhibit that the strong maximum excitation peaks appear at 260-283 nm and the strong maximum fluorescence emission bands at 367-412 nm, especially. Thermogravimetric analysis of the materials shows that about 55-68% of the initial polymer weights remain at 400 ${^{\circ}C}$ in nitrogen.

• 센서학회지
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• 제22권3호
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• pp.175-180
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• 2013

This paper describes the characteristics of cubic silicon carbide (3C-SiC) films grown on a carbonized Si(100) substrate, using hexamethyldisilane (HMDS, $Si_2(CH_3)_6$) as a safe organosilane single precursor in a nonflammable $H_2$/Ar ($H_2$ in Ar) mixture carrier gas by atmospheric pressure chemical vapor deposition (APCVD) at $1280^{\circ}C$. The growth process was performed under various conditions to determine the optimized growth and carbonization condition. Under the optimized condition, grown film has a single crystalline 3C-SiC with well crystallinity, small voids, low residual stress, low carrier concentration, and low RMS. Therefore, the 3C-SiC film on the carbonized Si (100) substrate is suitable to power device and MEMS fields.

• 한국세라믹학회지
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• 제41권5호
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• pp.349-352
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• 2004

Organic-inorganic hybrid sol based on ZrO$_2$-SiO$_2$ system was prepared by sol-gel process. Firstly, ZrO$_2$ non-aqueous precursor sol was synthesized and then organosilane compounds which include epoxy silane (GPTS; 3-g1ycidoxypropyl tri-methoxysilane) and acryl silane (ACS; (3-(tri-methoxysilyl)propylmethacrylate)) were added to ZrO$_2$precursor sol for hybridization. Finally, com-mercial silica sol was added to improve the mechanical properties. Synthesized organic-inorganic Zr-hybrid sol was coated on polycarbonate substrate for enhancing it’s mechanical properties, especially hardness. Vicker’s hardness of polycarbonate sub strate was increased from 13.6 to 17.8 MPa and its pencil hardness was increased from 2 to 7 H, respectively, after coating and drying at 10$0^{\circ}C$ for 30 min.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.6-6
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• 2010

This paper describes that single crystal cubic silicon (3C-SiC) films have been deposited on carbonized Si(100) substrate using hexamethyldisilane(HMDS, $Si_2(CH_3)_6$) as a safe organosilane single-source precursor and a nonflammable mixture of Ar and $H_2$ gas as the carrier gas by APCVD at $1280^{\circ}C$. The 3C-SiC film had a very good crystal quality without defects due to viods, a very low residual stress.

• 한국환경과학회지
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• 제16권6호
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• pp.689-698
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• 2007

Mesoporous silicas for heavy metals adsorption were prepared by co-condensation of surfactant as a template and Ludox HS-40 as a silica precursor. Various mesoporous silicas with the introduction of chelating ligands (mercaptopropyl and aminopropyl groups) were synthesized to remove heavy metal ions from aqueous solutions. The surface modification was conducted with a co-condensation process using the sequential or simultaneous addition of mesoporous silica and high concentration of the organosilane(3-mercaptopropyltrimethoxysilane and 3-aminopropyltriethoxysilane). These materials have been characterized by elemental analysis, XRD, SEM and TEM analysis. Adsorbents synthesized with 3-mercaptopropyltrimethoxysilane and 3-aminopropyltriethoxysilane shows a high loading capacity for Hg(II), Pb(II), Cd(II) and anion Cr(VI). Especially the one synthesized with a mercaptopropyl function has the highest adsorption capacity for Hg(II) and Cd(II).

• 폴리머
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• 제36권1호
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• pp.111-116
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• 2012

메조포러스 물질의 표면을 post-synthesis grafting method를 통해 표면을 기능화시킨 후 $(n-BuCp)_2ZrCl_2$/methylaluminoxane(MAO)를 담지하여 에틸렌 중합을 실시하였다. 아민기와 시안기를 가지는 유기실란 $N$-[(3-trimethoxysilyl)propyl]ethylenediamine(2NS), 4-(triethoxysilyl)butyronitrile(1NCy), 1-(3-triethoxysilylpropyl)-2-imidazoline(2NIm)는 메조포러스 물질의 표면 기능화에 사용되었다. SBA-15/2NS/$(n-BuCp)_2ZrCl_2$촉매 담지시 MAO의 양이 증가할수록 Zr 함량은 감소하였고 Al 함량은 증가하였다. 에틸렌 중합 활성은 MAO의 양이 증가할수록 급격히 증가함을 볼 수 있었다. 담지시간이 6시간일 때 가장 높은 활성을 보였다. 유기실란의 종류에 따른 활성 차이는 SBA-15/2NS/$(n-BuCp)_2ZrCl_2$ > SBA-15/2NIm/$(n-BuCp)_2ZrCl_2$ > SBA-15/1NCy/$(n-BuCp)_2ZrCl_2$ 순으로 감소하였다. 아민기를 두 개 갖는 2NS와 2NIm은 아민기를 하나 갖는 1NCy보다 $(n-BuCp)_2ZrCl_2$와 더 강하게 상호작용을 한다. 따라서 촉매 내 질소와 Zr함량이 증가할수록 활성은 증가하였다.

• 대한화학회지
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• 제38권1호
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• pp.55-60
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• 1994

유기규소 중합반응에서 나타나는 중간체 $Cp_2TiSiHPh(1),\;[Cp_2Ti]_2[{\mu}-HSi(HPh)][{\mu}-H]$ (2) 그리고 $[Cp_2TiSiH_2Ph]_2$ (3)화합물들의 전자구조를 EHT방법으로 연구하였다. 1 화합물의 안정한 구조는 Cs로 변형된 형태이고 $SiH_2$의 회전에너지는 약 14 kcal/mol로 나타났다. 전자결핍분자인 2와 3 화합물의 결합특성을 전자구조를 통하여 규명하였다. 또한 Ti금속이 Si-H의 $\sigma$ 결합과 작용할 가능성을 설명하였다.

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.533-537
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• 2007

This paper describes the heteroepitaxial growth of single-crystalline 3C-SiC (cubic silicon carbide) thin films on Si (100) wafers by atmospheric pressure chemical vapor deposition (APCVD) at 1350 oC for micro/nanoelectromechanical system (M/NEMS) applications, in which hexamethyldisilane (HMDS, Si2(CH3)6) was used as a safe organosilane single-source precursor. The HMDS flow rate was 0.5 sccm and the H2 carrier gas flow rate was 2.5 slm. The HMDS flow rate was important in obtaing a mirror-like crystalline surface. The growth rate of the 3C-SiC film in this work was 4.3 μm/h. A 3C-SiC epitaxial film grown on the Si (100) substrate was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and Raman scattering, respectively. These results show that the main chemical components of the grown film were single-crystalline 3C-SiC layers. The 3C-SiC film had a very good crystal quality without twins, defects or dislocations, and a very low residual stress.

• 대한화학회지
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• 제40권5호
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• pp.347-356
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• 1996

트리플산에 의한 phenylsilane 의 선태적 분해반응에서는 silyltriflate ester 결합을 형성하였다. 1 혹은 2당량배의 트리플산에 의한 $Ph_3SiH$과 carbosilane 고분자$(Ph_2SiCH_2CH_2CH_2)n$의 Ph기 치환반응에서는 1 혹은 2치환 silyltriflate ester 결합을 형성하였으며 이들과 allylmagnesium bromide와의 반응에 의해 이에 상응되는 화합물을 높은 수율로 얻었다. Carbosilane 고분자의 나무가지꼴 실란거대분자를 allylation 과 hydrosilation법에 의해 제3세대(G3)까지 합성하였다.