• Macromolecular Research
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• v.12 no.5
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• pp.431-436
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• 2004

Cross-linked network solid polymer electrolytes were prepared by means of in situ hydrosilylation between poly[hydromethylslioxane-g-oligo(ethylene oxide)] and diallyl or triallyl group-containing poly(ethylene glycols). The conductivities of the resulting polymer electrolytes were greatly enhanced upon the addition of poly(ethylene glycol) dimethyl ether (PEGDME) as an ion-conducting plasticizer. Conductivities of the cross-linked polymer electrolytes were more dependent on the molecular weight of PEGDME than on the cross-linkers. The maximum conductivity was found to be 5.6${\times}$10$\^$-4/ S/cm at 30$^{\circ}C$ for the sample containing 75 wt% of PEGDME (M$\_$n/ =400). These electrolytes exhibited electrochemical stability up to 4.5 V against the lithium reference electrode. We observed reversible electrochemical plating/stripping of lithium on the nickel electrode.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.289-298
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• 1996

Eight kinds of poly(oxyethylene, oxyisopropylene) dodecyl ethers were synthesized by adding ethylene oxide and isopropylene oxide with each 5 and 10 moles alternatively on dodecanol. The addition of EO and PO for eight kinds of sodium poly(oxyethylene, oxyisopropylene) dodecyl ether sulfates was identified with HPLC, $^1H$ NMR, hydroxy value, and IR spectrum. In order to verify the sulfation the number of EO and PO molecules was obtained by spectra and Epton method. The yields of products sulfated by chlorosulfonic acid were 90~96%.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.433-442
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• 1996

Electrochemical characteristics and physical properties of polymer electrolyte which immobilized lithium salts such as $LiClO_4$ and $LiCF_3SO_3$ and plasticizers such as ethylene carbonate(EC) and propylene carbonate(PC) in high molecular weight poly(ethylene oxide)[PEO] polymer was investigated. PEO-Li based polymer electrolyte with plasticizers showed ionic conductivity of $10^{-4}S/cm$ at room temperature and high electrochemical stability up to 4.5 V(vs. $Li^+/Li$), so it can be applied to lithium secondary battery. The crystallinity of PEO decreased with the addition of lithium salts and plasticizers, especially $LiClO_4$ and PC showed more effective than and $LiCF_3SO_3$ and EC. Glass transition temperature($T_g$) of polymer electrolyte increased with increasing lithium salt concentration whereas melting temperature ($T_m$) decreased. Polymer electrolyte with plasticizers crystallized at $6^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.37 no.9
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• pp.781-786
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• 1993

In the presence of $Mg^{2+}$, the interaction of nonionic surfactants, $nonylphenol-(ethylene oxide)_n$[NP-nEO; n = 12, 40, 100] with iodine in aqueous solution were investigated by UV-visible spectrophotometer. CMC (critical micelle concentration) was decreased with increasing $Mg^{2+}$ concentration, and those effects depend upon EO (ethylene oxide) numbers. Above CMC, the intensity of interaction peaks by the addition of $Mg^{2+}$ increased and then decreased. The increase in the intensity of the interaction peaks were attributed to the compactness of micelle in the presence of $Mg^{2+}$. These phenomena may be explained by the fact that the linear ethylene oxide chains, to be free configuration in aqueous solution, could form a psuedo-crown ether structures capable of forming complex with $Mg^{2+}$.

• Journal of the Korean Chemical Society
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• v.40 no.12
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• pp.748-755
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• 1996

The effects of temperature on the conformational properties of poly(ethylene oxide) (PEO) in aqueous and aqueous urea solutions are reported. The values of intrinsic viscosity and Huggins coefficients for the PEO dissolved in water and urea/water mixtures (urea concentration 0.2, 1, and 2 M) were obtained using a viscometry method and discussed with respect to the change of water structure. At low temperatures (below 22 $^{\circ}C)$, the PEO-water interaction is favorable and the chain can be extended, whereas at higher temperatures (above 24 $^{\circ}C)$, it is less favorable and the chain can be contracted by a hydrophobic hydration, i.e., the PEO-water interaction becomes to be unfavorable with the increase in temperature. As the urea is added to the system, the PEO chain can be more extended and huged by the perturbation of the structured water originating from the unfavorable PEO-water interaction. The effect of temperature on the intrinsic viscosity values shows an Arrhenius behavior. The activation energies of the viscous flow were obtained and discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1247-1250
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• 2008

This presentation highlights work from the authors' laboratories on the various kinds of oxide optical materials, mainly luminescence and pigment materials with different forms (powder, core-shell structures, thin film and patterning) prepared by the Pechini-type sol-gel (PSG) process. The PSG process which uses the common metal salts (nitrates, acetates, chlorides etc) as precursors and citric acid (CA) as chelating ligands of metal ions and polyhydroxy alcohol (such as ethylene glycol or poly ethylene glycol) as cross-linking agent to form a polymeric resin on molecular level, allowing the preparation of many forms of luminescent materials.

• Korean Journal of Heritage: History & Science
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• v.48 no.3
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• pp.46-59
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• 2015

This study was conducted focusing on the stability on materials of cultural property when the fumigant containing ethylene oxide was applied among some kinds of fumigant. Four kinds of specimens from paper, textile, metal and pigment were prepared to compare color difference, weight, surface condition before and after treatment and FT-IR analysis was carried out on specimens of paper and textile. In the case of fumigation treatment, it was conducted by two groups : one is made up of specimens with the non-fumigation as control groups, the other is made up of specimens treated with ethylene oxide + $HFC_{134a}$ and ethylene oxide + $CO_2$ as experimental groups. The result of color difference showed that there were color differences on the specimens of Hanji(Korean traditional paper), silver, cotton, ramie and yellow pigment. Especially, it was found out there was color change more than 6.0 on average from the silver specimen. However, in the silver specimen's case, color change in the non-fumigated specimen was relatively higher than those of fumigant-treated specimens, therefore, it is judged that fumigant doesn't have a decisive effect on color change in specimens, but required caution while fumigating. The result of weight measurement, there were totally 0~2% weight changes and the slightest change was found in the metal specimen, the biggest change in the papers. The result of microscopic observation on the surface of specimens showed color changes and especially, the biggest change on the silver specimen was observed. But no change in components was identified from FT-IR analysis of papers and textiles.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.527-531
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• 2009

Periodic mesoporous organosilicas (PMO) were synthesized using bis(triethoxy silyl) benzene as the precursor and dodecyl trimethyl ammonium bromide (DTMA) as the templating agent. From these results of XRD, TEM, and NMR, the pore structure of the material was confirmed to have a well-organized hexagonal structure. Poly(ethylene oxide) (PEO) was penetrated into PMO. From the DSC and XRD experiments, the polymer melting transition of crystalline polyethylene oxide (PEO) decreased then finally disappeared. These results prove that the polymer chains penetrate into the PMO channels, and penetrated polymer chains are constrained inside channels of PMO.

• Corrosion Science and Technology
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• v.22 no.3
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• pp.193-200
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• 2023

Titanium alloy (grade-4) is commonly used in industrial and medical applications. To improve its corrosion resistance and biocompatibility for medical use, it is necessary to form a titanium oxide film. In this study, the morphology of the oxide film formed by anodizing Ti-grade 4 using different electrolytes was analyzed. Wetting properties before and after surface modification with SAM coating were also observed. Electrolytes used were categorized as A, B, and C. Electrolyte A consisted of 0.3 M oxalic acid and ethylene glycol. Electrolyte B consisted of 0.1 M NH₄F and 0.1 M H₂O in ethylene glycol. Electrolyte C consisted of 0.07 M NH₄F and 1 M H₂O in ethylene glycol. Samples B and C exhibited a porous structure, while sample A formed a thickest oxide film with a droplet-like structure. AFM analysis and contact angle measurements showed that sample A with the highest roughness exhibited the best hydrophilicity. After surface modification with SAM coating, it displayed superior hydrophobicity. Despite having the thickest oxide film, sample A showed the lowest insulation resistance due to its irregular structure. On the other hand, sample C with a thick and regular porous oxide film demonstrated the highest insulation resistance.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.376-376
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• 2016

Poly(ethylene oxide) (PEO)/functionalized bacterial cellulose nanowhiskers (f-BCNW) (0.1 wt%) composite nanofibers were fabricated by electrospinning process and the thermomechanical properties were significantly enhanced more than the PEO and PEO/bacterial cellulose nanowhiskers (BCNW) (0.1 wt%) composite nanofibers. The functionalization of BCNW (f-BCNW) was performed by microwave plasma treatment for effects of nitrogen functionalization of chemically-driven BCNW. The N-containing functional groups of f-BCNW enhanced chemical bonding between the hydroxyl groups of the polymer chains in the PEO matrix and diameter size of PEO/f-BCNW (0.1 wt%) composite nanofibers were decreased more than PEO and PEO/BCNW (0.1 wt%) composite nanofibers on the same concentration. The strong interfacial interactions between the f-BCNW nanofillers and polymer matrix were improved the thermomechanical properties such as crystallization temperature, weight loss and glass transition temperature (Tg) compared to PEO and PEO/BCNW composites nanofibers. The results demonstrated that N2 plasma treatment of BCNW is very useful in improving thermal stability for bio-applications.