• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1353_1354
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• 2009

The OTFT devices had inverted staggered structures of Au/pentacene/ppMMA/ITO on PET substrate. The overall device performances of the flexible devices such as the operating voltage, the field effect mobility, the on/off ratio and the off current are somewhat worse than those of devices fabricated on glass substrates. Pentacene/ppMMA OTFT benchmarks (mobility, sub-threshold slope, on/off ratio) were comparable to that of solution cast PMMA, but below average when compared to other polymer gate dielectrics. However, threshold and drive voltages were among the lowest reported for a polymer gate dielectric, and surpassed only by ultra-thin SAM gate dielectrics.

• Journal of the Korean Society of Clothing and Textiles
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• v.10 no.2
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• pp.79-84
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• 1986

Methacrylic acid was graft polymerized with benzoyl peroxide in itiator onto the commercial PET film. Graft polymerization was carried out in emulsion, which consisted of BPO (1), chlorobenzene(8) as swelling agent, tween 80(1) and sodium lauryl sulfate(1) as emulsifier and water(1,000). Original PET film has poor reactivities and, so the film preswdled with benzyl alcohol($150^{\circ}C$, 1hr) was also examined. The graft yield of PET film was increased with reaction temperature and monomer concentration. The graft yield of preswelled PET film was higher than that of no-treated PET film. Moisture regain was linearly increased with graft yield. DSC thermodiagram showed the Tm of grafted PET film was same as that of original PET film. Grafted PET film was dyed with methylene blue solution. The photograph of the cross section showed that grafting was occured not at the center but near surfaces.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.215-215
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• 2006

The cyclic butylene terephthalte oligomer was synthesized and the composition of butylenes terephthalate cyclic oligomers was 51.2 % of dimer, 28.1 % of trimer, 7.9 % of tetramer, 8 % of pentamer and 4.8% of hexamer. Polybuthylene terephthalate was polymerized using this cyclic oligomer in the condition of melt process and supercritical process. And PBT/clay nanocomposite were manu- factured from melt process and supercritical process. Chlorodifluoro- methane(HCFC-22) was used as a solvent which has critical point ($Tc=96.2^{\circ}C$, Pc=49.7bar). Also polymer nanocomposite were manufactured using rapid expansion of supercritical solution process.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.105-109
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• 1998

Langasite({{{{ { La}_{ 3} {Ga }_{5 } {SiO }_{14 } , LGS}}}}) powder was prepared by a polymerized complex method based on the Pechini-type reaction. A mixed solution of ethylene glycol(EG), cotric acid(CA), lanthanum, gallium and silicon ions, with a molar ratio of EG:CA:La:Ga:Si=100:25:3:5:1, was polymerzed to from a transparent resin, which was used as a precursor for the synthesis of LGS. X-ray diffraction(XRD) patterns indicated that the LGS phase could be formed by the heat-treatment in air at 1000$^{\circ}C$ for 3hrs

• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.109-112
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• 1997

Morphology of carbonate crystals grown on the surface of artificial cell membranes was controlled by changing the interfacial chemistry. For octadecyltriethoxysilane (OTE) films with terminal methyl groups interacting little with an aqueous calcium carbonate solution calcite (104) crystals were formed. Polymerized pentacosadiynoic acid (PDA) films with terminal carboxylic acid groups induced deposition of calcite (012) crystals aligned along with each other within a polymer domain. On the other hand, stearyl alcohol (StOH) films with terminal hydroxyl groups induced deposition of aragonite crystals. When PDA was mixed with StOH, the 8:1 PDA:StOH (molar ratio) film produced dominating calcite (012) crystals without any crystal alignment, and the 4:1 mixture film produced minor calcite (012) crystals and major aragonite crystals. For the 2:1, 1:1, 1:2, and 1:4 mixture films, aragonite crystals were dominating. Hence, it is found that the chemical composition at the interface plays a very important role in controlling the morphology of deposited carbonate crystals.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.3
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• pp.215-222
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• 2001

Polyaniline-Camphorsulfonic Acid Emeraldine Salt(PANI-CSA ES) was prepared by doping Polyaniline Ermeralidine Base(PANI EB) with DL-10-Camphorsulfonic Acid(CSA). PANI-CSA ES was solved in an organic solvent by ultrasonification for different periods of time and its surface resistivity was measured. Several PANI-CSA ES solutions solved in different organic solvents were prepared and their surface resistivities were measured. Thermal stability of film casted with PANI-CAS ES solution in m-cresol was estimated by measuring its surface conductivity and the content of this moisture and organic solvents. PANI-CSA ES was blended with different polymeric binders to improve its physical properties and the surface resistivities of several kinds of PANI-CSA ES blends were measured as a function of the content of PANI-CSA ES. PANI-CSA ES polymerized by 1-step oxidative polymerization was prepared and its surface resistivity was measured.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.3083-3087
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• 2013

Diacetylene lipid monomers possess the capability to self-assemble into vesicles via polymerization under ultraviolet irradiation, resulting in the formation of polydiacetylene (PDA) liposomes. Exposure of the polymerized vesicles to external stimuli is known to induce a unique blue-to-red color transition. The cyclic oligosaccharide ${\alpha}$-cyclodextrin known for its use in many applications, such as drug delivery, purification, and stimulus sensing, is able to form an inclusion complex with poly(ethylene glycol) (PEG) in aqueous solution. In this study, we prepared polymeric liposomes with PEG (PEG-PDA) with the aim of improving the stability of the vesicles and colorimetric response toward ${\alpha}$-cyclodextrin. We demonstrated that PEG-PDA liposome displays unique characteristics compared with native PDA liposome and it also shows apparent chromic properties of the inclusion complex formation with ${\alpha}$-cyclodextrin.

• Carbon letters
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• v.7 no.4
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• pp.266-270
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• 2006

Multi-walled carbon nanotube-poly methyl methacrylate (MWNT/PMMA) nanocomposite has been prepared by in situ polymerization of MMA dispersed with MWNTs. The MWNTs were functionalized by nitric acid and sulfuric acid treatment, and this was confirmed by FTIR spectrometer. The solution mixture of MWNTs and MMA was partially polymerized at $80^{\circ}C$, followed by the addition of AIBN and polymerization at $50^{\circ}C$. The MWNT-PMMA composite was prepared by casting the pre-polymer on the glass plate, and the optical properties have been studied using UV-vis spectrometer. The acid treated MWNTs were well dispersed in MMA with fairly good dispersion stability, while flocculation and sedimentation was observed from raw MWNTs in MMA.

• Journal of the Korean Ceramic Society
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• v.23 no.4
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• pp.78-84
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• 1986

Zirconium acetate solution which was obtained from $ZrOCl_2$.$8H_2O$ was condensed polymerized and drawn to fibers by pulling method. Drawn gel fibers fired at 130$0^{\circ}C$ were short porous and mechanically weak. But addition of CaO about 13m/o caused the fibers to have the cubic structure and relatively dense microstructure. In order to clarify the condition for the synthesis of zirconia fibers viscosity measurement DTA-TG analysis X-ray diffraction infrared spectroscopy, SEM and specific surface area were studied.

• Journal of the Korean Ceramic Society
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• v.26 no.3
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• pp.371-380
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• 1989

The purpose of this experiment is to elucidate the reaction mechanism concerning to the formation of crystalline BaTiO3 synthesized by adding the pH control agent(KOH soln) in TiCl4 and BaCl2 solution (Wet direct synthetic method). In this expeirment, it is identified that the amorphous barium-titanate having Ba-O-Ti bonding is formed above pH5 due to the -OH- ion and Ti-gel is formed below pH5 due to the polymerization of metatitanic acid. The bonding of the amorphous Ba-O-Ti is identified by FT-IR spectrum and crystallization temperature is about 82$0^{\circ}C$. If the pH of the above system according to the -OH- ion concentration is above 13.8, the polymerized metatitanic acid will be depolymerized and produce [TiO3]2+ion and crystalline BaTiO3 is formed by reacting the produced [TiO3]-- ion with the active Ba++ ion.