• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.406-414
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• 2010

A novel polyacrylamide grafted hydrous ferric oxide adsorbent composite has been synthesized by using glow discharge electrolysis plasma. To optimize the synthesis conditions, the following parameters were examined in detail: applied power, discharge time, post polymerization temperature, post polymerization time, amount of crosslinking agent and hydrous ferric oxide gel added and so on. The adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The removal percentage of the adsorbent in Pb(II) solution was examined and the data obtained showed that the adsorbent composite has a high capacity for lead ion. For the use in wastewater treatment, the thermodynamic and kinetic of Pb(II)-capture were also studied. Results indicated that the adsorption reaction was a spontaneous and an endothermic process, and it seems to be obeyed a pseudo-secondorder rate model. Moreover, the adsorption isotherm of Pb(II)-capture is following the Langmuir and Freundlich isotherm models.

• 한국미생물·생명공학회지
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• 제41권4호
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• pp.456-461
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• 2013

단일가닥 DNA와 이중가닥 DNA의 흡착 율의 차이를 이용하여, 본 연구는 산화 그래핀에 흡착된 단일 가닥 DNA을 사용하여 Klenow fragment의 효소 활성을 검출하기 위하여 실시간 형광에세이 방법을 사용했다. 실험 결과에 의하면, 산화그래핀에 흡착된 형광표지 ssDNA는 형광이 ��칭(quenching) 되지만, cDNA 첨가에 의해서 흡착된 단일가닥 DNA가 유리되었다. Klenow fragment의 활성을 측정하기 위해서 형광표지 틀(template) DNA, 산화그래핀과 시발체(primer)가 존재할 때, 고분자 반응이 진행됨에 따라 ��칭된 형광세기가 증가하였다. 그리고 겔 전기영동 실험은 산화 그래핀에서 DNA 합성과 hybridization 반응을 확인하였다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.156-157
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• 2006

Quasi-living polymerization conditions for the copolymerization of ethylene and functionalized norbornenes can be achieved by using an initiator system comprising $[N-(2,6-diisopropylphenyl)-2-(2,6-diisopropylphenylimino)-propanamidato-{\kappa}^2N,O]Ni({\Box}^1-CH_2Ph)(PMe_3)\;and\;Ni(COD)_2$. It is possible with this polymerization system to obtain block-copolymer and tapered structures. The latter form microdomains similar to those of standard block co-polymers. The mechanism of the reaction will also be discussed.

• Carbon letters
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• 제14권4호
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• pp.251-254
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• 2013

In this study, poly(amic acid) was prepared via a polycondensation reaction of 3,3'-dihydroxybenzidine and pyromellitic dianhydride in an N-methyl-2-pyrrolidone solution; reduced graphene oxide/polybenzoxazole (r-GO/PBO) composite films, which significantly increased the electrical conductivity, were successfully fabricated. GO was prepared from graphite using Brodie's method. The GO was used as nanofillers for the preparation of r-GO/PBO composites through an in situ polymerization. The addition of 50 wt% GO led to a significant increase in the electrical conductivity of the composite films by more than sixteen orders of magnitude compared with that of pure PBO films as a result of the electrical percolation networks in the r-GO during the thermal treatment at various temperatures within the films.

• 대한화학회지
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• 제17권3호
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• pp.207-212
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• 1973

毛細灌法을 利用하여 여러가지 混合溶媒系(dioxane-n-butanol, dioxane-sec-butanol, dioxane-ethyleneglycol, dioxane-kerosene)중에서 polyvinylacetate의 희박용액을 機械的으로 切斷하여 그 결과로 얻어진 平均切斷速度定數(k) 및 極限重合度(g)를 moleculare dimension이 동일한 조건하에서 比較검토하였다. 그 결과 k보다는 g의 값이 사용하는 solvent의 종류에 따라 크게 영향을 받음을 알았으며 이에 關하여 考察하였다.

• 공업화학
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• 제20권1호
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• pp.75-79
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• 2009

아닐린 단량체(monomer)의 화학적 중합시 사슬성장의 핵심생성구간에서 아닐린 이합체(dimer, p-aminodiphenylamine)의 몰 비율을 조절하여 반응용액에 첨가함으로써 분자량(Mw, 20000~10000) 조절이 가능한 폴리아닐린을 합성 하였다. 중합반응의 개시로 부터 측정된 반응시간에 따른 open-circuit potential 측정결과 첨가된 이합체의 몰수가 증가할수록 중합속도가 빨라짐을 확인하였다. 첨가된 이합체의 몰수가 증가할수록 UV/Vis. 측정결과 합성된 폴리아닐린의 흡수띄가 단파장으로 이동하였으며, GPC 측정결과 분자량이 감소하는 것을 볼 수 있었다.

• 한국응용과학기술학회지
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• 제25권4호
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• pp.485-494
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• 2008

The acrylic coating emulsions were prepared by the emulsion polymerization to protect the surface of steel plate from the corrosion chemicals like acid, base and salt water. MMA(methyl methacrylate), styrene, BA(butyl acrylate), and 2-HEMA(2-hydroxyethyl methacrylate) were used as monomer. KPS(potassium persulfate) and SBS(sodium bisulfite) as redox initiator and SDBS(sodium dodecylbenzene sulfonate) as emulsifier were used on the emulsion polymerization reaction. The most stable in-situ coating was obtained when 10% of MMA was added. Both particle size and quantity in emulsion were decreased as increasing the mount of SDBS. the most stable prepared coating emulsion with polyisocyanate crosslinker showed very high anticorrosion properties on the coated steel layer to salt water, whereas no significant improvement of anticorrosion property to acdic and basic condition it showed.

• Macromolecular Research
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• 제8권3호
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• pp.131-136
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• 2000

The synthesis of poly(2-ethynylpyridine) having glycidyl functionality was performed by the direct polymerization of 2-ethynylpyridine and epibromohydrin under mild reaction conditions without any initiator and catalysts. The polymerization proceeded well to give the resulting poly(2-ethynylpyridinium bromide) with a glycidyl functionality having relativity high molecular weight in high yields. The polymer structure was characterized by various instrumental methods to have the conjugated polymer backbone structure having glycidyl functionality. This ionic polymer was completely soluble in water, methanol, DMF, DMSO, and N,N-dimethylacetamide, but insoluble in THF, toluene, acetone, nitrobenzene, and n-hexane. This polymer system exhibited the UV-visible absorption around 300 and 520 nm and red photoluminescence spectrum around 725 nm.

• 공업화학
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• 제17권5호
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• pp.561-564
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• 2006

$SnO_{2}$가 도핑된 아나타제형의 $TiO_{2}$ 분말을 tin (IV) bis (acetylacetonate) dichloride와 titanium diisopropoxide bis (acetyl- acetonate)를 출발물질로, polyethylene glycol (PEG)을 첨가하여 합성하였다. 반응과정에 대한 구조변화를 FT-IR로 추적하였고, 입자의 모양과 형태 및 결정의 구조는 FE-SEM과 XRD 분석기로 관찰하였다. 합성된 분말의 광촉매 효과는 환경오염물질로 indigo carmine (IC)을 선택하여 UV-visible 스펙트라로 관찰하였다.