• 분석과학
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• 제28권1호
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• pp.8-16
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• 2015

We prepared a novel electrochemical gas sensor (EG sensor) based on interdigitated electrode (IDE) coated with vinyl ionic liquids (ILs) as electrolyte and Pt-Ru-Mo/MWNT electrocatalysts for occurring redox-active of CNCl gas. The vinyl ILs such as 1-butyl-3-(vinylbenzyl)imidazolium chloride, $[BVBI]^+Cl^-$, and 3-hexyl-1-vinylimidazolium bromide, $[HVI]^+Br^-$, were synthesized by $SN_2$ reaction in order to use electrolyte. The Pt-Ru-Mo/MWNT electrocatalysts were also prepared by one-step radiation-induced reduction of metal ions in the presence of MWNTs as supports. The fabricated EG sensor with vinyl ILs electrolyte was evaluated through optical microscopy (OM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The prepared EG sensor is clearly detected over 2.0 ppm CNCl gas and is exhibited a liner relationship between current and concentration over a region of 10-100 ppm.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.104-107
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• 2003

Poly(vinyl alcohol) (PVA) obtained by the saponification of poly(vinyl ester) like poly(vinyl acetate) o. poly(vinyl pivalate) is a linear semicrystalline polymer, which has been widely used as fibers for clothes and industries, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials[1-3]. PVA fibers and films have high tensile and compressive strengths, high tensile modulus, and good abrasion resistance due to its highest crystalline lattice modulus. (omitted)

• 폴리머
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• 제35권5호
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• pp.409-418
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• 2011

A novel silicone (Si) containing vinylic monomer, N-(3-(triethoxysilyl)propyl) methacrylamide (TESPMA), based on 3-aminopropyltriethoxysilane (APTES) and methacryloyl chloride (MCl) has been synthesized for formulation of waterborne polyurethane (WPU). Two types of vinyl group containing Si, methacryloxypropyltriethoxysilane (MPTES) and triethoxyvinylsilane (TEVS), have been used as coupling reagents for comparison of the effects of Si kinds with TESPMA on the WPU. A series of new siliconized WPU, vinyl acetate/vinyl ester of versatic acid (VAc-Veova), TESPMA, MPTES and TEVS hybrid latexes have been successfully prepared by emulsion polymerization in the presence of WPU dispersion.

• Elastomers and Composites
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• 제44권3호
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• pp.323-328
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• 2009

고분자 용융 같은 물질의 유변학적인 성질은 전단 흐름에서 복잡한 비 뉴톤 유동 현상을 보인다. 이들 유동성질은 유동단위와 유동부분 사이의 상호작용의 특성에 의하여 결정된다. poly(vinyl alcohol) hydrogel의 비 뉴톤유동 곡선을 cone-plate 레오메타로 여러 온도와 여러 농도 조건에서 얻었다. PVA hydrogel의 유동 곡선을 비 뉴톤 유동식에 적용시켜 유동 파라메타를 얻었다. 유동현상은 전단 속도가 증가함에 따라 전단박화의 틱소트로피 현상을 나타내었다.

• 통합자연과학논문집
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• 제6권2호
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• pp.71-75
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• 2013

$Bu_3Sn$-endded poly(vinyl)s with biological activity were obtained by the radical polymerization of vinyl monomers using thianthrene cation radical/$^nBu_3H$. Thianthrene cation and stannyl radicals promoted the homopolymerization and copolymerization of styrene and ethyl vinyl ether having number average molecular weights of 2000-3100. Tributyltin hydride functions as a chain transfer agent. Such polymereization by cationic thianthrene and stannyl radicals could provide some clues for the biological reaction in living animals. Plausible polymerization mechanisms were suggested.

• 한국안전학회지
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• 제26권5호
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• pp.46-53
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• 2011

The risk assessment of thermal behavior and runaway reaction cased by an exothermic batch process in manufacture of the vinyl acetate resin are described in the present paper. The aim of the study was to evaluate the risk of runaway reaction with operating parameters such as a reaction inhibitor, reaction temperature and a mount of methanol charged in the vinyl acetate polymerization process. The experiments were performed by a sort of calorimetry with the Multimax reactor system as a screening tool to investigate runaway reaction. From the experimental results, it was found that we could occur the auto acceleration for reaction of raw materials with operating parameters over $65^{\circ}C$ of reaction temperature in the vinyl acetate polymerization process.

• Bulletin of the Korean Chemical Society
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• 제3권2호
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• pp.60-66
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• 1982

In relation to denaturation of proteins, thermally induced conformational change of poly(D-glutamic acid) was studied in the presence of poly(vinyl alcohol) at low pH, where poly(D-glutamic acid) undergoes a helix-to-${\beta}$ transition without any other polymer. In a dilute solution, poly(vinyl alcohol) enhanced the ${\alpah}-to-{\beta}_1$ transition of poly(D-glutamic acid) due to intermolecular interaction between the two polymers. On the other hand, this conformational change was interrupted to a large extent in a concentrated solution, due to the interpenetration of poly(vinyl alcohol) chain into poly(D-glutamic acid) chain which prevented the intramolecular association of poly(D-glutamic acid) chain. A conformational change from ${\beta}_1\;to\;{\beta}_2$ of poly(D-glutamic acid) was observed for the films obtained by casting during annealing the mixture solutions. The ${\beta}_2$ content in the cast film increased with increasing poly(vinyl alcohol) content in the mixture.

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.246-250
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• 1987

The reaction of aryl iodides or bromides with olefins in the presence of 1 mol % of $PdCl_2(PPh_3)_2$ and 3 equiv. of $n-Bu_3N\; at\; 100^{\circ}C$ in carbon monoxide atmosphere gave the corresponding aryl vinyl ketones in good yields with small amount of vinylated 1-aryl olefins. But, when the reaction was proceeded under the 10 atm of carbon monoxide, aryl vinyl ${\alpha}$-diketones and aryl vinyl ketones were obtained in moderate to good yields. The reaction was tolerant of a wide variety of functional groups on either the aryl halides or olefin compounds. Reactivity of aryl halide decrease in the order; aryl iodide > aryl bromide ${\gg}$aryl chloride. In general, the reaction proceeded well and gave good yields of aryl vinyl ketones and aryl vinyl ${\alpha}$-diketones when reactants are substituted with electron withdrawing groups.

• 한국응용과학기술학회지
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• 제15권3호
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• pp.55-60
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• 1998

The sodium ${\alpha}-sulfo$ fatty acid vinyl ester oligomers, which are oligomer type surfactants were prepared by polymerization with fatty acid vinyl acetate. The ${\alpha}-sulfonation$ of fatty acid vinyl ester oligomers were carried by direct addition of sulfur trioxide. The dispersing performance of oligomer type anionic surfactants and sodium dodecyl sulfate(SDS) in the aqueous suspension of iron oxide and titanium dioxide particles was evaluated by particle size distribution and zeta-potential measurement. As results, the particles of iron oxide and titanium dioxide were flocculated by addition of small amount of oligomer type anionic surfactants and sodium dodecyl sulfate(SDS), then the flocks redispersed by more addition of oligomer type anionic surfactants and SDS. The flocculation, redispersion process was observed in lower concentration range of oligomer type anionic surfactants than SDS. Especially, the dispersing action of sodium ${\alpha}-sulfo$ palmitic acid vinyl ester oligomer was better than sodium ${\alpha}-sulfo$ lauric acid vinyl ester oligomer.

• 한국공간구조학회논문집
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• 제14권4호
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• pp.81-88
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• 2014

Construction of vinyl house structures is increasing because they do not have a large cross section as non-permanent structures. Vinyl house structures are apt to collapse by snow load because they have a small size member as a temporary building. Therefore, it is very important to ensure not only the stiffness of the individual member, but also the overall stability of three-dimensional arch-type vinyl house structures. The purpose of this study is to estimate the stability of arch-type vinyl house structures that have a various curvature under the vertical load such as snow load. As a result of the study, the buckling load of V27 model is the largest, and the values of buckling load have a tendency to increase with increasing H(height of arch) in the case of $H{\leq}2.75m$, but to decrease with increasing H in the case of $H{\geq}2.75m$.