• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.78-83
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• 2001

In this work, the surface of inorganic fillers were modified with some functional groups such as stearic acid, aliphatic long chain, vinylsilane and aminosilane to control the interaction between inorganic fillers and polymer matrix. Ethylene-vinyl acetate copolymers (EVA) with various amount of vinyl-acetate content and copolyether-ester elastomer were used as polymer matrix. The addition of inorganic fillers increases flame retardancy, but results in steep drop of electrical and mechanical properties, which may be caused by the defect in the interface between organic/inorganic hybrid composites. The hybrid composites are found to show better mechanical properties and higher volume resistivities as inorganic fillers are well dispersed and have good adhesion with polymer matrix. Also, the most effective type of functional group coated on fillers depends on the chemical structure of polymer.

• Macromolecular Research
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• v.17 no.12
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• pp.987-994
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• 2009

Palladium nanoparticles having cubic silsesquioxanes (POSS) (Pd-POSS) were produced by the reaction of palladium (II) acetate and octa(3-aminopropyl)octasilsesquioxane octahydrochloride (POSS-${NH_3}^+$ in methanol at room temperature. Functionalized multiwalled carbon nanotubes (MWNT-COOH) were prepared by acid treatment of pristine MWNTs. The hybrid nanocomposites of Pd-POSS and MWNT-COOH (Pd-MWNT nanocomposites) were synthesized by self-assembly method via ionic interaction between positively charged Pd-POSS and negatively charged MWNT-$COO^-$. The spherical aggregates of Pd-POSS with a diameter of 40-60 urn were well attached to the surfaces of MWNT-COOH on Silicon wafer. The composition, structure, and surface morphology of Pd-MWNT nanocomposites were studied by UV-vis spectrophotometer, energy dispersive spectrum (EDX), scanning electron microscopy (SEM), and atomic force microscope (AFM).

• Polymer(Korea)
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• v.35 no.1
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• pp.94-98
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• 2011

Poly(2-hydroxyethyl methacrylate), PHEMA, hybrid gels containing Pluronic and acrylic acid (AAc) were prepared as new biocompatible and stimuli-responsive hydrogels by photo-polymerization technique. The prepared hybrid gel showed reversible, temperature-responsive swelling behavior due to the presence of Pluronic component, which underwent sol-gel transition at an elevated temperature to cause gel shrinkage. The hydrogel also exhibited increased swelling degrees and pH-sensitivity due to the AAc component with ionizable carboxylic acid groups. The microporous gel morphology and its changes upon stimuli was observed by scanning electron microscopy.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.181-182
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• 2013

• Polymer(Korea)
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• v.35 no.5
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• pp.488-492
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• 2011

Three isocyanatopropyldimethoxysilylpolydimethylsiloxanes(IDMSi-PDMS) were synthesised from the reaction of isocyanatopropyltrimethoxysilane with monohydroxyl group termainated PDMS having different molecular weight($M_n$=5000, 10000, and 20000). Then PDMS modified polyurethane hybrid elastomer(PSMPH) were prepared from the reaction of IDMSi-PDMS with ${\alpha}$, ${\omega}$-hydroxyl group terminated polyurethane. PSMPH sealant was prepared by compounding PSMPH elastomer with additives such as plasticizer, adhesion promoter, crosslinking agent, vicosity increasing agent, inorganic filler, and catalyst at room temperature under nitrogen atmosphere. The methoxy group in the PSMPH sealant should be crosslinked with the hydroxyl group in the building stone or moisture by typical sol-gel reaction. The adhesive strength of the sealant having PDMS of $M_n$=5000 showed 40.28 kg of maxium load and 20.14 kg of break load. The shrinkage rate of the sealant having PDMS of $M_n$=20000 was 5.7% as the best result. Also, their skin over time, slump, oil content after 8 days under oil soaked paper and alkaline resistance characteristics show good results.

• Polymer(Korea)
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• v.33 no.2
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• pp.97-103
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• 2009

Ultra-high molecular weight polyethylene (UHMWPE)/functionalized-MWNT hybrid films were prepared by the solution intercalation method, using 4-cumylphenol-MWNT (CP-MWNT) as the functionalized-MWNT. The variation of the thermomechanical properties, morphology, gas permeability, and optical transparency of the hybrid films with CP-MWNT content in the range of 0$\sim$2.00 wt% were examined. The newly synthesized UHMWPE/functionalized-MWNT hybrid films were characterized by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and a universal tensile machine (UTM). It was found that the addition of only a small amount of functionalized-MWNT was sufficient to improve the thermomechanical properties of the UHMWPE hybrid films, with maximum enhancement being observed in the CP-MWNT loading in the range 0.50 to 1.00 wt%. The maximum enhancement in the oxygen gas barrier was also found at the functionalized MWNT content of 1.00 wt%. In this work, the thermomechanical properties and gas permeability of the hybrid films were found to be better than those of pure UHMWPE.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.309-309
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• 2006

Latest developments on hybrid nanostructured materials fabricated by applying self-assembly strategies on organic/inorganic nanotemplates are discussed. Within this frame, numerous functional nanomaterials including arrays of composite metal/semiconductor nanoparticles, planar waveguides and functional multilayer thin films are generated using self-assembled polymers as templates or building blocks. In particular, surface plasmon resonance based optical sensing is employed to investigate nanofabrication processes occurring in nanoscale dimention. We also suggest unprecedented pathways to hybrid supramolecular multilayer nanoarchitectures in 1D or 2D geometry via layer-by-layer self-assembly.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.779-780
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• 2009

New inverted architecture of a hybrid inorganic-organic light-emitting diode, utilizing ZrO2 electron-injecting layer, is presented. The thickness of the ZrO2, as well as the annealing of the light-emitting polymer, is found critical to obtain good performance. A range of light-emitting polymers is shown to operate efficiently in the proposed architecture.

• Bulletin of the Korean Chemical Society
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• v.28 no.6
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• pp.1015-1020
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• 2007

A simple approach to prepare arrays of Au/TiO2 composite nanoparticles by using Au-loaded block copolymers as templates combined with a sol-gel process is described. The organic-inorganic hybrid films with closely packed inorganic nanodomains in organic matrix are produced by spin coating the mixtures of polystyrene-block-poly(ethylene oxide) (PS-b-PEO)/HAuCl4 solution and sol-gel precursor solution. After removal of the organic matrix with deep UV irradiation, arrays of Au/TiO2 composite nanoparticles with different compositions or particle sizes can be easily produced. Different photoluminescence (PL) emission spectra from an organic-inorganic hybrid film and arrays of Au/TiO2 composite nanoparticles indicate that TiO2 and Au components exist as separate state in the initial hybrid film and form composite nanoparticles after the removal of the block copolymer matrix.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1386-1389
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• 2008

Conventional viewing angle switching electrode requires pixel division and additional liquid crystal panel. Hence the conventional viewing angle switching has low aperture ratio and high thickness. In this paper we proposed new viewing angle switching using hybrid aligned nematic mode by fringe-field electrode field (named HAN-FFS) with single liquid crystal panel. The fringe-field switching electrode is located at the bottom, and the additional common electrode is located at the top of the cell to control viewing angle. The proposed device is free from additional liquid crystal panel and pixel division. Consequently, the suggested structure has not only high aperture ratio but also show an excellent potential for viewing angle switching.