• Journal of Information Display
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• 제12권4호
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• pp.191-194
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• 2011

A symmetric-viewing inverse-twisted-nematic (ITN) liquid crystal display (LCD) with alternating alignment layers was developed using a stamping-assisted rubbing (SAR) technique. A patterned layer of a fluorinated acrylate polymer was transferred onto the first rubbed vertical-alignment layer prepared on a substrate by stamping. The fluorinated acrylate polymer provided a protective layer covering the first rubbed alignment layer during the second rubbing process, which promoted the vertical alignment of the LC molecules. The LC cell in the ITN geometry with two orthogonally rubbed alignment layers showed symmetric-viewing characteristics with fourfold symmetry. The SAR technique was shown to be a mask-free alignment method of producing multidomains for symmetric-viewing LCDs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.389-390
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• 2008

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.426-426
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• 2008

Blend membranes were prepared by solvent casting method from sulfonated fluorinated poly(arylene ether)s (SDFF) and chemically modified polyvinylidene fluoride (mPVdF) in isopropanol and were evaluated as proton exchange membrane electrolytes in PEMFC. $^1H$-NMR, differential scanning calorimeter and thermogravimetric analysis was utilized to characterize the structure of the blend membranes (SDFF/mPVDF) and effects of mPVDF content on the properties of the membrane such as water uptake and proton conductivity were also investigated.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.177-179
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• 2007

An object of the present study is to provide a hollow fiber membrane humidifier capable of improving the humidification efficiency while lowering the pressure loss, and is suitably usable for PEMFC(Polymer Electrolyte Membrane Fuel Cell). The performance of PEMFC is decisively dependent on the humidity of the electrolyte membrane(fluorinated membrane) and a humidifier plays an important role in moisturizing electrolyte membrane. Especially, this humidifier is a passive type(power-free) item and is volumetrically optimized. In this research, we propose the substitutes for the expensive fluorinated humidifier materials and the optimum dry-jet wet spinning conditions of hollow fiber membrane. In addition to that, This study will present an performance of an humidifier and compare computational results with the experimental data.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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• pp.43-44
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• 2009

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.933-935
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• 2002

In this paper, new non-chiral molecules with semi-fluorinated alkyl chains were synthesized varying the structure of central bent core unit. Their mesomorphic properties were investigated by DSC and polarized microscopy. The compound with 1,3-dihydroxy phenylene unit could form an enantiomeric smectic phase, but the remaining compounds with bent-core mesogenic unit were not liquid crystalline. In this presentation, their x-ray measurement and electro-optical property will be also described.

• Fibers and Polymers
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• 제3권3호
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• pp.91-96
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• 2002

Polyhydroxyamides derivatized with trifluorormethyl ether and trifluoromethyl ester groups were investigated as possible candidates for a new flame retardant polymer. Model compounds for these derivatized polyhydroxyamides were synthesized and their cyclization chemistry was investigated. The model compound study revealed that trifluorornethyl ester group containing model compounds can cyclize on heating, while trifluoromethyl ether group containing model compounds cannot. The non-fluorinated ether and ether derivatives behaved similarly. The trifluoromethyl ester derivatized polyhydroxyamides were synthesized according to the procedures for the model compounds. TGA characterization revealed that the fluorinated polymers have nearly same thermal stability as the underivatized PHA after cyclization.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.213-214
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• 2000

New light-emitting polyimides were synthesized from the conventional polycondensation of 5,5'-bis(4-aminophenyl)-2,2'bifuryl (PFDA) with fluorinated and non-fluorinated aromatic dianhydrides, providing a good quality of thin films: 6F-PFDA PI and ODPA-PFDA PI. Their UV-visible absorbance and photoluminescent characteristics were investigated. The polymers emit blue and blue-greenish light in a quantum yield of 7.3-14.9%, depending on the polymer backbone.

• Corrosion Science and Technology
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• 제14권5호
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• pp.207-212
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• 2015

The purpose of this research was to synthesize fluorine modified waterborne polyurethane dispersion (F-WPU) by soap-free (internal emulsifier) emulsion polymerization techniques, to prepare coating solution based on fluorine modified waterborne polyurethane dispersion (F-WPU) and to compare the chemical and thermo-mechanical properties on the electrogalvanized steel sheet. Environmentally friendly F-WPU was prepared with a fluorinated polyol containing 60 wt% of fluorine. There are various ways of combining a wide variety of fluorinated polyols and diisocyanate to exhibit novel properties of waterborne polyurethane dispersion. Components of coating solution were largely divided into 4 kinds i.e., F-WPU, acrylic emulsion, silane coupling agent, and colloidal silicate. F-WPU coating solution on the electro-galvanized steel sheet showed excellent properties of corrosion resistance, alkali resistance and heat resistance, as compared to other coating solutions using a general waterborne resin. The F-WPU coating solution's reliable effects are possibly due to the fluorine atoms incorporated even in a small amount of F-WPU.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.41-48
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• 2011

The wettabilities of the partially fluorinated polymers (ethylene-tetrafluoroethylene copolymer (ETFE), ethylenechlorotrifluoroethylene copolymer (ECTFE), and poly(vinylidene fluoride) (PVDF)) were investigated by contact angle measurements. Zisman plots for ETFE and ECTFE exhibited linear relationships, while the Zisman plot for PVDF showed a slight curvature, which was interpreted to indicate strong non-dispersive interactions between the surface and the contacting liquids. The Lifshitz-van der Waals forces of the fluoropolymers were estimated to increase in the order of ETFE < PVDF $\ll$ ECTFE. An evaluation of the polar or "acid-base" interaction energies showed that PVDF, which possesses the most acidic hydrogens among the examined fluoropolymers, has the strongest acid-base interactions.