• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.590-600
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• 1987

Silicone-containing polyamide-imides were prepared from bis(p-chlorocarbonylphenyl)diphenylsilane (BCCDPS), pyromellitic dianhydride(PMDA) and diamines. The thermal characteristics of the above polymers had been carefully studied using a thermogravimetric analyzer. The thermal stability of polymer was decreased with increasing contents of bis(p-carbonylphenyl)diphenylsilane units(BCDPS). The effect of diamine on thermal stability of polymer led benzidine > m-phenylenediamine> 4,4'-diaminodiphenyl ether > 4,4'-diaminodiphenyl sulfone. The activation energy of degradation of polymer obtained by Friedman method increased as the contents of BCDPS in the polymer decreased. The degradation temperature of polymers generally increased as the activation energy increased. The solubility of polymer increased as the content of BCDPS increased except polymers prepared with benzidine.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.51-55
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• 2005

In vitro ${\beta}$-lactamase inhibitory activity of 6-triazole exomethylenepenam compounds (1, 2, 3, 4, 5 and 6) was compared with clavulanic acid, sulbactam and tazobactam. The inhibitory activity of 3, 4 and 5 was stronger than those of sulbactam, clavulanic acid and tazobactam against Type IV enzymes. And, inhibitory activity of 3 and 4 was stronger than those of sulbactam, clavulanic acid and tazobactam against Type III enzymes. The in vitro antimicrobial activity of 3, 4 and 5 combined with ampicillin was better than those with sulbactam and with cefoperazone was compared with the sulbactam against ${\beta}$-lactamase producing 27 strains. The synergistic activity of (Z)-form compounds (3 and 5) was better than that of (E)-form compound (4) and sulfone compound (5) was better than sulfide compound (3).

• Journal of Information Display
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• v.12 no.1
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• pp.1-4
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• 2011

A complementary inverter was fabricated using pentacene and N-N -dioctyl-3,4,9,10-perylene tetracarboxylic diimide-C (PTCDI-C8) for p- and n-type transistors on a poly(ether sulfone) substrate, respectively. The mobilities of the p- and n-type transistors were 0.056 and 0.013 $cm^2$/Vs, respectively. The inverter, which was composed of p- and n-type transistors, showed a gain of 48.6 when $V_{DD}$ = -40V and at the maximum noise margin of $V_{DD}$/2. A ring oscillator was also fabricated by cascading five inverters. The five-stage ring oscillator showed the maximum output frequency of 10 kHz when $V_{DD}$ = -170 V.

• Journal of Surface Science and Engineering
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• v.41 no.3
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• pp.102-108
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• 2008

In this paper, the LiF and polymer thin film as passivation layer have been evaporated on green OLED devices. HDPE, polyacenaphthylene, polytetrafluoroethylene, poly(2,6-dimethyl-1,4-pheneylene oxide), poly sulfone and poly(dimer-acid-co-alkyl poly-amine) have been used as polymer materials. The optical transmittance of evaporated polymer thin film was very good as an above 90% in visible range. The morphology of polymer thin film was measured by AFM. As a result of the measurement average roughness($R_a$) value of the polysulfone was very low as 2.2 nm. The green OLED devices with a structure of ITO/HIL/HTL/EML/Buffer/Al in series of various passivation films were fabricated and analyzed. It was observed that an OLED device with LiF as first passivation film has shown the good electrical and optical property, and all kind of polymer films did not influence on the I-V-L characteristics and the life time of OLED devices. Therefore, we found that polymer layer played a key role as a buffer layer between the inorganic passivation layers to relieve the stress of the inorganic layers.

• Korean Membrane Journal
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• v.3 no.1
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• pp.9-16
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• 2001

The diamide-diamine having carboxylic acid was prepared by direct condensation of 1,2,4-benzenetricarboxylic acid with bits[4- (3-aminophenoxy ) phenyl] sulfone and bits(4-aminouhenyl)-1,4- diisopropylbenzene in medium consisting of triphenylphosphite, LiCl, and N-methyl-2-pyrrolidone. Copoly (amide-imide) derivatives with high molecular weight could be synthesized by one-step polycondensation of prepared diamide-diamine having carboxylic acid and various dianhydride compounds. Depending on the chemical structure and composition of polymer backbones, the viscosities of polymers were found to range between 0.87∼ 1.57 dL/B. All the polymers showed good thermal stability up to 320$\^{C}$ and the 10% weight loss temperature was observed in the range of 450∼540$\^{C}$ in a thermogravimetric traces. The glass transition was recorded in the temperature range of 200 ∼ 270$\^{C}$. All the polymers showed an amorphous nature on a differential scanning calorimetric thermograms. These polymers generally had good mechanical properties and readily soluble in various polar solvents. Further, it was proved that their properties could be determined from the composition.

• Bulletin of the Korean Chemical Society
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• v.16 no.5
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• pp.416-421
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• 1995

The approximate rates and stoichiometry of the reaction of excess lithium gallium hydride with selected organic compounds containing representative functional groups were examined under the standard conditions (diethyl ether, 0 $^{\circ}C)$ in order to compare its reducing characteristics with lithium aluminum hydride and lithium borohydride previously reported, and enlarge the scope of its applicability as a reducing agent. Alcohols, phenol, and amines evolve hydrogen rapidly and quantitatively. However lithium gallium hydride reacts with only one active hydrogen of primary amine. Aldehydes and ketones of diverse structure are rapidly reduced to the corresponding alcohols. Conjugated aldehyde and ketone such as cinnamaldehyde and methyl vinyl ketone are rapidly reduced to the corresponding saturated alcohols. p-Benzoquinone is mainly reduces to hydroquinone. Caproic acid and benzoic acid liberate hydrogen rapidly and quantitatively, but reduction proceeds slowly. The acid chlorides and esters tested are all rapidly reduced to the corresponding alcohols. Alkyl halides and epoxides are reduced rapidly with an uptake of 1 equiv of hydride. Styrene oxide is reduced to give 1-phenylethanol quantitatively. Primary amides are reduced slowly. Benzonitrile consumes 2.0 equiv of hydride rapidly, whereas capronitrile is reduced slowly. Nitro compounds consumed 2.9 equiv of hydride, of which 1.9 equiv is for reduction, whereas azobenzene, and azoxybenzene are inert toward this reagent. Cyclohexanone oxime is reduced consuming 2.0 equiv of hydride for reduction at a moderate rate. Pyridine is inert toward this reagent. Disulfides and sulfoxides are reduced slowly, whereas sulfide, sulfone, and sulfonate are inert under these reaction conditions. Sulfonic acid evolves 1 equiv of hydrogen instantly, but reduction is not proceeded.

• Textile Coloration and Finishing
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• v.34 no.4
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• pp.234-240
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• 2022

Use of processed timber can help reduce environmental damage and the economic burden of resources (important problems with use of raw timber) and can meet the needs of various fields where the sensibility of raw timber is required. Veneer wood is positioned as a high-value-added product due to its luxury and beauty, and it is used in various fields as a building-related material, such as interior decoration, furniture, flooring, building interior materials, and lumber. Dyeing is necessary to enhance the aesthetic appearance of this pattern and to expand its use. Therefore, in this study, we compared and analyzed the dye ability of oak-patterned materials with reactive dyes, and evaluated their performance as interior materials. As a result, the oak pattern was dyed with 9 kinds of reactive dyes and a comparative analysis was performed. The most suitable conditions are 50℃, 2 hours, and 0.5% o.w.f. In addition, evaluating resilience to daylight, resilience to rubbing, fire resistance, and flame retardance, yielded results suitable for use as an interior material. In this study, the dyeability of veneer dyed under various conditions using reactive dyes was compared and analyzed the performance as an interior material was evaluated.

• Journal of the Korean Chemical Society
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• v.20 no.1
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• pp.59-72
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• 1976

The addition of one mole of zinc chloride to 2.33 moles of sodium borohydride in tetrahydrofuran at room temperature gave a clear chloride-free supernatant solution of zinc borohydride after stirring three days and standing at room temperature.The approximate rates and stoichiometry of the reaction of zinc borohydride with 54 selected organic compounds were determined in order to test the utility of the reagent as a selective reducing agent. Aldehydes and ketones were reduced rapidly, aromatic ketones being somewhat slowly, and the double bond of cinnamaldehyde was not attacked. Acyl halides were reduced rapidly within one hour, but acid anhydrides were reduced at a moderate rate. Carboxylic acids, both aliphatic and aromatic, were slowly reduced to alcoholic stage. Esters were inert to this reagent but a cyclic ester, γ-butyrolactone, was slowly attacked. Primary amides were reduced slowly with partial evolution of hydrogen, whereas tertiary amides underwent neither reduction nor hydrogen evolution. Epoxides and nitriles were all inert, as well as nitro, azo, and azoxy compounds. Cyclohexanone oxime and phenyl isocyanate were reduced slowly but pyridine was inert. Disulfide, sulfoxide, sulfone and sulfonic acids were stable to this reagent.

• Journal of the Korean Electrochemical Society
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• v.17 no.1
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• pp.44-48
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• 2014

Sulfonated poly(arylene ether sulfone)-cerium composite membranes with improved oxidative stability were prepared for proton exchange membrane fuel cell application. Oxidative stability of the composite membranes changed depending on the amount of incorporated metal. Their water uptake, IEC and proton conductivity were also affected. ICP analysis confirmed trace of cerium ion in the composite membranes and $^1H$-NMR indicated successful coordination of sulfonic acid groups with the metal ions. Increasing amount of the cerium ion resulted in decrease in proton conductivities and water uptake, but enhanced oxidative stabilities. A hydrogen peroxide exposure equipment was used for the test of oxidative stability of the composite membranes, which enabled to mimic fuel cell operating condition compared with conventional Fenton's test.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.283.2-283.2
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• 2016

최근 ZnO는 무독성, 저가격, 수소 플라즈마에 대한 내구성 및 열적 안정성 등의 활발히 연구되고 있으며, III족 원소(Al, Ga, In) 불순물을 도핑하여 전기적 성질의 열적 불안정성을 해결하고 전기적 성질을 향상 시키고 또한 밴드갭 에너지가 3.3 eV 이상으로 증가하여 가시광선 영역에서 광투과율이 높은 투명도 전성 재료를 제공할 수 있다. 본 연구에서는 RF Magnetron Sputtering을 이용하여 내열성과 광학적 측면에서 우수한 성능을 가지는 PES 기판에 표면 에너지를 높이고 치밀한 구조의 박막을 증착하기 위해서 $O_2$ 플라즈마 처리를 하여 ZnO계 투명 전도막을 제작함으로써 투명전극에서 요구하는 $10^{-3}{\Omega}{\cdot}cm$ 이하의 낮은 비저항과 80% 이상의 광투과율을 가지는 방안에 대하여 연구하였다. PES 기판 위에 고밀도 $O_2$ 플라즈마를 이용하여 전 처리를 실시한 후 4인치의 Al-doped ZnO(ZnO 98 wt% : $Al_2O_3$ 2 wt%), AZO의 타겟을 이용하여 상온에서 RF Magnetron Sputtering 법으로 AZO 박막을 증착하였다. PES 기판상의 AZO 박막 두께가(100~400nm) 증가함에 따라 캐리어 농도와 홀 이동도가 점차 증가하는 경향을 보였다. 이는 박막 두께가 증가할수록 면저항과 비저항은 감소하며 결정립 크기가 커지고 결정입계에서 산란이 줄어들기 때문에 전기적 특성이 개선된 것으로 판단된다. 고밀도 $O_2$ 플라즈마 표면처리 시간이 증가함에 따라 플라스틱 기판의 결합에너지와 부착력이 증가하여 AZO 박막의 결정립 크기를 증가시키며, 접촉각은 감소하였다. 또한 급속열처리 온도가 증가함에 따라 전기적 특성과 광학적 특성이 향상됨을 확인할 수 있었다. 제작된 AZO 박막은 급속열처리 시간 10분에서 온도 $200^{\circ}C$일 때, 캐리어 농도 $2.32{\times}10^{21}cm^{-3}$, 홀 이동도 $4.3cm^{-2}/V$로 가장 높은 것을 확인할 수 있었고, 가장 낮은 비저항 $1.07{\times}10^{-3}{\Omega}{\cdot}cm$과 가시광 영역(300 nm ~ 1100 nm)에서의 AZO 박막의 광 투과율은 약 86%를 얻을 수 있었다.