• 한국세라믹학회지
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• 제45권10호
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• pp.605-609
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• 2008

This work describes the preparation of functionalized magnetic nanoparticles(MNPs) and their bioapplication to human DNA separation. Silica coated MNPs were prepared by changing the volume ratio of tetraethyl orthosilicate(TEOS) for controlled coating thickness on the original nanoparticle of MNPs. The sol-gel process in silica coating on MNPs surface was adapted for relatively mild reaction condition, low-cost, and surfactant-free. And then amino functionalized magnetic nanoparticles were synthesized using amine groups as surface modifiers. The result of adsorption efficiency for human DNA with amino-functionalized silica coated MNPs was calculated as a function of the number of amine groups.

• 한국연초학회지
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• 제27권2호
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• pp.171-177
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• 2005

Coconut based activated carbon and silica-gels were impregnated with 3-aminopropyltri ethoxysilan(APS) and N-(2-aminoethyl)-3-aminopropyl triethoxysilane (AEAPS) in order to investigate the effect of the amine group and the pore size of the supports on the removal of hydrogen cyanide(HCN) and aldehydes in mainstream smoke(MS). The physicochemical properties of the supports were analyzed by using thermal gravity analyzer(TGA), $N_2$ adsorption and desorption isotherms$(BET,\;N_2)$, and SEM-EDS. According to our experimental data, there was no significant difference in the delivery amount of HCN and aldehydes of non-functionalized silica-gels having meso-pores bigger than $20\AA$. In the case of silica-gels functionalized with APS(APS silica-gel), the delivery amounts of hydrogen cyanide(HCN) and aldehydes decreased with the increase of APS concentration. Silica-gel functionalized with AEAPS(AEAPS silica-gel) showed higher removal efficiency than that of APS silica-gels. The delivery amounts of HCN and aldehydes of activated carbon impregnated with APS and AEAPS increased with the increase of the APS and AEAPS concentrations. In accordance with the specific surface area analysis results, APS and AEAPS molecules decreased the specific surface area by blocking the micro-pores of the activated carbon. The volatile organic components removal efficiency by the micro-pores was higher than that of the amine group impregnated into the activated carbon.

• Bulletin of the Korean Chemical Society
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• 제28권11호
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• pp.1985-1992
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• 2007

Ordered mesoporous silica (MCM-41) materials with different textural properties were prepared using alkyl (dodecyl, cetyl, eicosane) trimethyl ammonium bromide (DTAB, CTAB, ETAB, respectively) as structure directing surfactants, functionalized with amine groups and used as adsorbent for the toxic metal ions, Cr (VI), As (V), Pb (II) and Hg (II). Amino functionalization of mesoporous MCM-41 was achieved by cocondensation of N-[3-(trimethoxysilyl)-propyl] aniline with tetraethyl orthosilicate. Adsorption isotherm and adsorption capacity of the amine functionalized materials for Cr (VI), As (V), Pb (II) and Hg (II) ions were followed by inductively coupled plasma mass spectrometry (ICP-MS). Results demonstrate that amine functionalized MCM-41 prepared with ETAB showed higher adsorption capacity for Cr (VI), As (V), Pb (II) and Hg (II) ions in comparison to MCM-41 prepared with CTAB and DTAB. The higher adsorption capacity for MCM-41(ETAB) was correlated with amine content in the material (determined by CHN analysis) and relative decrease in pore volume and pore diameter. X-ray diffraction (XRD) analysis, nitrogen adsorptiondesorption measurements and Fourier Transform infrared spectrometry (FTIR) were used to follow the changes in the textural parameters and surface properties of the mesoporous materials as a result of amine functionalization to correlate with the adsorption characteristics. The adsorption process was found to depend on the pH of the medium.

• Korean Chemical Engineering Research
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• 제60권3호
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• pp.407-413
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• 2022

본 연구는 생체 모방 폴리아민 복합체를 통해 아민 그룹(amine group)이 기능화 되고 크기 조절이 간편한 실리카 나노입자의 합성 방법에 관한 것이다. 먼저, 실리카 나노입자를 합성하기 위한 촉매로써 polyallylamine hydrochloride(PAH)와 인산 이온(phosphate ion)으로 구성된 폴리아민 나노 복합체를 형성하였다. 복합체의 크기는 pH 조건에 따라 가역적인 조절이 가능하다. 나노 복합체에 존재하는 PAH 주쇄의 다량의 아민 그룹들은 silicic acid의 축합(condensation) 반응을 촉매 하며, 결과적으로 실리카 나노입자를 매우 빠른 시간 내에 합성할 수 있다. 최종적으로 pH 조건에 따라 다양한 크기를 갖는 실리카 나노 입자를 합성하였다. 실리카 나노입자의 합성 과정에서 촉매 역할을 하는 PAH는 나노입자의 내부 및 표면에 함입되고 합성된 실리카 나노입자의 표면에 아민 그룹이 노출된다. 본 방법은 실리카 나노입자의 합성과 표면개질이 동시에 이루어지며, 아민 그룹이 도입된 실리카 나노입자를 다양한 크기로 조절하여 손쉽게 합성할 수 있다. 최종적으로, 본 연구에서 제시한 방법은 기존의 합성법 보다 온화한 조건 하에서 단시간 내에 실리카 나노입자를 합성할 수 있으며, 생체 공학 및 재료 분야에서 적용되어 넓게 활용될 수 있다.

• 폴리머
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• 제36권6호
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• pp.693-698
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• 2012

본 연구에서는 높은 분자량의 polylactide(PLA)를 중합하기 위하여 aluminum isopropyl oxide($Al(O-i-Pr)_3$)를 아민기로 표면 기능화된 실리카에 담지하고 이를 촉매로 이용하여 생성된 PLA의 중합특성을 확인하였다. 담지촉매는 먼저 실리카 표면을 아민기를 갖는 실란화합물로 기능화한 후 $Al(O-i-Pr)_3$을 in-situ 합성하였다. 기능기에 담지된 $Al(O-i-Pr)_3$는 MAO(methyl aluminoxane) 존재하에 중합활성을 보였다. $115^{\circ}C$에서는 표면 기능화된 아민기양이 증가할수록 전환율과 분자량이 증가하였고, $130^{\circ}C$에서는 표면 기능화된 아민기양이 증가할수록 전환율은 감소하였으나 분자량은 크게 증가하여 표면 기능화된 아민기양이 3.0 mmol일 경우 44000 g/mol로 가장 높은 분자량을 얻었다. GPC curve를 통해 $115^{\circ}C$ 중합온도에서는 분자량 분포곡선이 bimodal 형태에서 저분자량 부분이 크게 증가하여 shoulder 형태로 변화하였으며 $130^{\circ}C$에서는 GPC 단일피크를 보였다. 균일계 $Al(O-i-Pr)_3$ 촉매보다 아민기로 표면 기능화된 실리카에 담지된 $Al(O-i-Pr)_3$ 촉매가 더 높은 활성과 고분자량의 PLA를 합성할 수 있었다.

• Korean Chemical Engineering Research
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• 제44권4호
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• pp.417-423
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• 2006

실리카계 메조 물질 MCM-41 지지체 위에 여러 방법으로 aminopropyltrimethoxysilane(APMS)을 표면 기능화 시킨 염기촉매를 제조하였고 표준 염기반응인 Knoevenagel 축합반응을 수행하여 촉매적 활성을 측정하였다. Methyltrimethoxysilane으로 추가 표면처리하거나, APMS를 염소함유 유기실란과 축합하여 2차 아민 형성 후 고정화시킨 MCM-41 촉매(BAPM)를 제조한 결과, MCM-41 표면의 잔류 OH를 제거하고 물과의 수소결합으로 아민 활성점의 기능이 약화되는 것을 억제하여 높은 TON을 얻을 수 있었다. 코팅에 의해 표면에 많은 양의 아민이 고정화된 MCM-41은, 세공 내부의 반응 공간이 줄어들고, 인접한 아민 간의 수소결합으로 인하여 낮은 염기도가 예상되며 촉매 활성도 상대적으로 낮았다. 제조한 촉매 중에는 BAPM이 촉매 활성이 가장 우수하였다.

• Elastomers and Composites
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• 제50권2호
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• pp.110-118
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• 2015

In this study, diethylaminoethyl methacrylate-styrene-butadiene terpolymer (DEAEMA-SBR), in which diethylaminoethyl methacrylate (DEAEMA) was introduced to the SBR molecule as a third monomer, was synthesized by cold emulsion polymerization. It is expected that amine group introduced to a rubber molecule would improve dispersion of silica by the formation of hydrogen bond (or ionic coupling) between the amine group and silanol groups of silica surface. The chemical structure of DEAEMA-SBR was analyzed using proton nuclear magnetic resonance spectroscopy (H-NMR), Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). Then, various properties of DEAEMA-SBR/silica composite such as crosslink density, bound rubber content, abrasion resistance, and mechanical properties were evaluated. As a result, bound rubber content and crosslink density of DEAEMA-SBR/silica compound were higher than those of the SBR 1721 composite. Abrasion resistance and moduli at 300% elongation of the DEAEMA-SBR/silica composite were better than those of SBR 1721 composite due to the high bound rubber content and crosslink density. These results are attributed to high affinity between DEAEMA-SBR and silica. The proposed study suggests that DEAEMA-SBR can help to improve mechanical properties and abrasion resistance of the tire tread part.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3715-3721
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• 2013

In this study, the behavior of cells on the modified surface, and the correlation between the modified substrates and the response of cells is described. A close-packed layer of nano-sized silica beads was prepared on a coverslip, and the adhesion, proliferation, and migration of BALB/3T3 fibroblast cells on the silica layer was monitered. The 550 nm silica beads were synthesized by the hydrolysis and condensation reaction of tetraethylorthosilicate in basic solution. The amine groups were introduced onto the surfaces of silica particles by treatment with 3-aminopropyltrimethoxysilane. The close-packed layer of silica beads on the coverslip was obtained by the reaction of the amine-functionalized silica beads and the (3-triethoxysilyl)propylsuccinic anhydride treated coverslip. BALB/3T3 fibroblast cells were loaded on bare glass, APTMS coated glass, and silica bead coated glass with the same initial cell density, and the migration and proliferation of cells on the substrates was investigated. The cells were fixed and stained with antibodies in order to analyze the changes in the actin filaments and nuclei after culture on the different surfaces. The motility of cells on the silica bead coated glass was greater than that of the cells cultured on the control substrate. The growth rate of cells on the silica bead coated glass was slower than that of the control. Because the close-packed layer of silica beads gave an embossed surface, the adhesion of cells was very weak compared to the smooth surfaces. These results indicate that the adhesion of cells on the substrates is very important, and the actin filaments might play key roles in the migration and proliferation of cells. The nuclei of the cells were shrunk on the weakly adhered surfaces, and the S1 stage in which DNA is duplicated in the cell dividing processes might be retarded. As a result, the rate of proliferation of cells was decreased compared to the smooth surface of the control. In conclusion, the results described here are very important in the understanding of the interaction between implanted materials and biosystems.

• 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.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1381-1384
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• 2005

Surface modification of tridimensional cubic mesoporous silica, SBA-16, was investigated with pendant arm functionalized cobalt diaminosarcophagine (diAMsar) cage complex which covalently grafted onto the silica surface through the silication with sylanol group. The spectroscopic results showed that the mesoporous structure was preserved under the $[Co(diAMsar)]^{3+}$ grafting reaction condition. Successful grafting prevented the cobalt diAMsar cage from leaching out from the SBA-16 support.