• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.871-877
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• 2005

Recent progress in the filed of transition-metal mediated C-H bond activation has had a great influence on organic synthesis. Among such transition-metal catalyzed reactions, ortho-functionalization via the chelationassisted strategy has been paid great attentions as one of the powerful methodologies for converting aromatic compounds into ones that are more functionalized at the exclusively ortho-position. In this context, various transition metal-catalyzed ortho-functionalizations such as alkylation, alkenylation, silylation and carbonylation are described briefly and their prospects are suggested.

• 폴리머
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• 제34권2호
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• pp.159-165
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• 2010

리빙 음이온 중합에 의해 sec-BuLi으로 개시된 polystyryllithium (PSLi)과 polybutadienyllithium (PBDLi)의 연쇄 말단에 di(2-pyridyl)ketone(DPK)을 반응시켜 dipyridine이 말단 관능화된 폴리스티렌과 폴리부타디엔을 각각 합성하였다. 분자량이 1000~2000 g/mol인 PSLi과 PBDLi을 사용하여 TMEDA 존재하에서 말단 DPK-관능화 반응 후 GPC에 의한 분자량 특성분석과 $^1H$-NMR, $^{13}C$-NMR 분석에 의한 고분자 말단 구조 분석을 통하여 말단 관능화 수율과 함께 유기리튬의 피리딘 링 친핵성 부가 반응으로 인한 커플링 현상을 확인하였다. PBDLi에 DPK를 부가하는 일반적인 말단 관능화 방법에 비하여 역으로 부가하는 방법에서 최대 9% 정도의 커플링 정도와 86% 이상의 관능화 수율을 보였다. 이 반응에서 LiCl 첨가효과는 없었으며, 반응온도가 낮을수록 높은 관능화 수율을 나타내었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.491-491
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• 2013

A novel plasma system has been developed for 3-dimensional modification of the carbon nano-powders. Improvement of dispersion of these nano materials are studied by plasma discharge, not using chemical modification. The plasma process is considered to great advantages over wet chemical process due to environmental, economic viewpoint, and uniformity over the treated volume. The uniform dispersion is a critical factor for these material's nano composite applications. Using this plasma system, graphene, carbon black, and CNT was treated and functionalized. Several key discharge conditions such as Ar/H2/O2 or Ar/H2/NH3 gas ratio, treatment time, power, feeder's vibration frequency are investigated. Hydrophobic of graphene has turned some more into hydrophilic by reaction test with water, electrophoresis, surface contact angle test, and turbidity analysis. The oxygen content ratio in the plasma treated CNT has increased about 3.7 times than the untreatedone. In the case of graphene and carbon black, the oxygen- and nitrogen- content has been enhanced average 10%. O-H (N-H) peak, C-O (C-N) peak, and C=O (C=N) peak data have been detected by FTIR measurement and intensified compared to before-plasma treatment due to O2 or NH3 content.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3463-3466
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• 2013

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.539-540
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• 2010

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제38차 학술발표대회
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• pp.77-79
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• 2008

Polynitro fullerenes were synthesized by reaction C-60 in benzen solution with a mixture of NaNO$_2$ and HNO$_3$. Hydrolysis of polynitro fullerenes in aqueous NaOH gave the corresponding polyhydroxylated fullerenes. Sulfonation reaction was carried out in pyridine solution of ClSO$_3$H. Infrared spectra of the resultant fullerene derivatives showed the characteristic IR bands, corresponding to absorptions of O-H, N-O, and SO$_3$Na functions. Electric resistivity and thermal transmittance of wool fiber absorbed with the water-soluble C-60 were investigated. Thermal transmittances of wool fiber were increased with increasing water-soluble C-60 concentrations, but electric conductivity were decreased with raising water-soluble C-60 uptake values.

• 청정기술
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• 제20권2호
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• pp.116-122
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• 2014

수열합성 또는 후처리 방법을 통해 산 또는 염기능을 나타내는 다양한 종류의 이원기능 금속-유기 구조체 물질을 제조하여 대표적인 방향제 원료 중 하나인 자스민알데하이드(jasminaldehyde)를 합성하기 위한 벤즈알데하이드(benzaldehyde, $C_6H_5CHO$)와 헵탄알(heptanal, $C_6H_{13}CHO$)의 알돌 축합반응의 촉매로 활용하였다. 실험 결과, 산 또는 염기점 모두에서 축합반응이 진행되었으며, 촉매 성능은 기능기의 도입 여부 및 종류와 금속-유기 구조체의 물리적인 특성에 크게 의존하였다. Jasminaldehyde 선택도는 황산 기능기를 도입한 경우에는 금속-유기 골격체의 종류에 상관없이 감소하였으나, 아민 기능기를 도입한 경우에는 금속-유기 골격체의 종류에 따라 상반된 경향을 나타내었다. 평가한 촉매 중 MIL-101의 촉매 성능이 가장 우수하였는데, 이러한 결과는 MIL-101이 알돌 축합반응의 촉매로 작용하기에 충분한 산량과 적당한 산세기를 가지고 있으며, 세공 크기가 넓어 크기가 큰 생성물의 물질이동 측면에서 유리하기 때문인 것으로 판단된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.315-315
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• 2011

The ring formation and electronic properties of furan adsorbed on graphene layers grown on 6H-SiC(0001) has been investigated using atomic force microscopy (AFM), near edge X-ray absorption fine structure (NEXAFS) spectra for the C K-edge, and high resolution photoemission spectroscopy (HRPES). Moreover, we observed that furan molecules adsorbed on graphene could be used for chemical functionalization via the lone pair of electrons on the oxygen group, allowing chemical doping. We also found that furan spontaneously formed rings with one of three different bonding configurations and the electronic properties of the ring formed by furan on graphene can be described using by AFM, NEXAFS and HRPES, respectively.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3644-3649
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• 2011

Multinuclear solid-state nuclear magnetic resonance (NMR) experiments were performed to investigate the local structure changes of nanoporous silica during hydrothermal treatment and surface modification with 3-aminopropyltriethoxysilane (3-APTES). The nanoporous silica was prepared by sol-gel polymerization using inexpensive sodium silicate as a silica precursor. Using $^1H$ magic angle spinning (MAS) NMR spectra, the hydroxyl groups, which play an important role in surface reactions, were probed. Various silicon sites such as $Q^2$, $Q^3$, $Q^4$, $T^2$, and $T^3$ were identified with $^{29}Si$ cross polarization (CP) MAS NMR spectra and quantified with $^{29}Si$ MAS NMR spectra. The results indicated that about 25% of the silica surface was modified. $^1H$ and $^{29}Si$ NMR data proved that the hydrothermal treatment induced dehydration and dehyroxylation. The $^{13}C$ CP MAS and $^1H$ MAS NMR spectra of 3-APTES attached on the surface of nanoporous silica revealed that the amines of the 3-aminopropyl groups were in the chemical state of ${NH_3}^+$ rather than $NH_2$.

• 한국안광학회지
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• 제9권2호
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• pp.481-489
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• 2004

Poly(triazine bissulfide)s는 상간이동촉매하에서 bis(4-chloro-3-nitrophenyl)sulfone와 6-dibutylamino-1,3,5-triazine-2,4-dithiol로도 합성하였으며, 또한 m-dibromide xylene와 p-dibromide xylene으로 cetyltrimethyl ammonium bromide와 함께 $70^{\circ}C$에서 24시간 동안 6-dibutylamino-1,3,5-triazine-2,4-dithiol로 반응시켜서도 합성하였다. 캐스트필름을 만들기 위해서 합성한 이들에 대한 용해도, 열적 성질, 평균분자량 등에 대해서 좋은 결과를 얻었다. 이러한 결과는 기능성 광학플라스틱 재료인 고분자물질을 합성하는데 있어서 중요한 것임을 보여주는 것이다. 최대대수정도는 $50{\sim}60^{\circ}C$이상에서 0.57~1.40dl/g의 값을 보였다.