• 폴리머
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• 제32권1호
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• pp.85-89
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• 2008

이온성 액체인 N-methoxymethyl-N-methylpyrrolidium bis(trifluoro-methansulfonyl)imide (MPSI)를 첨가제로 함유하는 acrylate 계열의 단량체를 다관능기형 acrylate 가교제와 함께 carbonate 용매에서 중합, 겔형의 고분자 전해질을 합성하였다. 고분자 전해질의 이온전도성은 고분자의 함량, 가교제의 종류, 이온성 액체의 함량에 따라 측정되었으며, 인장강도를 조사하여 고분자 및 이온성 액체의 함량이 기계적 물성에 미치는 영향을 파악하였다. 그 결과 성분의 최적화는 고분자 함량 15 wt%, 이온성액체 30 wt% 그리고 5 wt%의 가교제를 함유한 겔 전해액으로 달성되었고, 0.5 MPa의 기계적 물성과 0.8 mS/cm의 우수한 상온 이온 전도도를 나타내었다.

• Macromolecular Research
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• 제16권5호
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• pp.424-428
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• 2008

We prepared an ionic gel polymer electrolyte for dye-sensitized solar cells (DSSCs) without leakage problem. Triiodide compound (BTDI) was synthesized by the reaction of benzene tricarbonyl trichloride with diethylene glycol monotosylate and subsequent substitution of tosylate by iodide using NaI. Bisimidazole was prepared by the reaction of imidazole with the triethylene glycol ditosylate under strongly basic condition provided by NaH. BTDI and bisimidazole dissolved in an ionic liquid were injected into the cells and permeated into the $TiO_2$ nanopores. In situ crosslinking was then carried out by heating to form a network structure of poly(imidazolium iodide), thereby converting the ionic liquid electrolytes to a gel or a quasi-solid state. A monomer (BTDI and bisimidazole) concentration in the electrolytes of as low as 30 wt% was sufficient to form a stable gel type electrolyte. The DSSCs based on the gel polymer electrolytes showed a power conversion efficiency of as high as 1.15% with a short circuit current density of $5.69\;mAcm^{-2}$, an open circuit voltage of 0.525 V, and a fill factor of 0.43.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.608-612
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• 2012

We investigated the cycling behavior of $Li_4Ti_5O_{12}$ electrode in a cross-linked gel polymer electrolyte based on non-flammable ionic liquid consisting of 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide and vinylene carbonate. The $Li_4Ti_5O_{12}$ electrodes in ionic liquid-based gel polymer electrolytes exhibited reversible cycling behavior with good capacity retention. Cycling data and electrochemical impedance spectroscopy analyses revealed that the optimum content of the cross-linking agent necessary to ensure both acceptable initial discharge capacity and good capacity retention was about 8 wt %.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.168-172
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• 2018

This study first investigates the effect of the choice of cation on three different ionic-liquid-based gel polymer electrolytes (ILPEs) with polyimide membranes. The preparation of three ILPEs based on electrospun membranes of PI and incorporating a room-temperature ionic liquid, 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide complexed with lithium bis(trifluoromethylsulfonyl)imide, is described. ILPE-EMImTFSI has an ionic conductivity as high as $5.3{\times}10^{-3}S\;cm^{-1}$ at $30^{\circ}C$. Furthermore, it shows higher thermal stability and electrochemical oxidation stability compared to the other two ILPEs because of its stronger bonds. These results indicate that polyimide-based ILPE-EMImTFSI is a good candidate for use in high-safety rechargeable lithium metal batteries.

• Journal of Electrochemical Science and Technology
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• 제8권3호
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• pp.257-264
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• 2017

A polymeric ionic liquid, poly(1-methyl 3-(2-acryloyloxypropyl) imidazolium iodide) (PMAPII), was synthesized as a single-iodide-ion-conducting polymer and employed in a gel polymer electrolyte. Gel polymer electrolytes prepared from iodine, 4-tert-butylpyridine, ${\gamma}$-butyrolactone, and PMAPII were applied in quasi-solid-state dye-sensitized solar cells (DSSCs). The addition of 16 wt.% PMAPII provided the most favorable environment, striking a compromise between the iodide ion concentration and the ionic mobility, which resulted in the highest conversion efficiency of the resulting DSSCs. The quasi-solid-state DSSC assembled with the optimized gel polymer electrolyte exhibited a relatively high conversion efficiency of 7.67% under AM 1.5 illumination at $100mA\;cm^{-2}$ and better stability than that of the DSSC with a liquid electrolyte.

• Bulletin of the Korean Chemical Society
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• 제22권10호
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• pp.1136-1140
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• 2001

• 한국재료학회지
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• 제32권12호
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• pp.533-537
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• 2022

Flexible zinc-air batteries have many merits, including low cost, high safety, environmentally friendliness applicability, etc. One of the key factors to improve the performance of flexible zinc-air batteries is to use a gel electrolyte. In this study, gel electrolytes were synthesized from potato, sweet potato, and corn starch. In a comparison of each starch, the corn starch-based gel electrolyte showed the highest discharge capacity of 12.41 mAh/cm² in 20 mA and 6.47 mAh/cm² in 30 mA. It also delivered a higher specific discharge capacity of 7.06 mAh/cm² than the other materials after 100° bending. In addition, the electrochemical impedance spectroscopy (EIS) was analyzed to calculate the ionic conductivity. The potato, sweet potato, and corn starch-based gel electrolytes showed electrolyte resistances (Re) of 0.306, 0.298, and 0.207 Ω, respectively. In addition, the corn starch-based gel electrolyte delivered the highest ionic conductivity of 0.121 S cm^-1 among the other gel electrolytes. Thus, the corn starch-based gel electrolyte was verified to improve the performance of flexible zinc-air batteries.

• 전기화학회지
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• 제6권2호
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• pp.141-144
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• 2003

Proton conducting polymeric gels as the electrolytes of electrochemical capacitors have been prepared by two different methods: 1) swelling a polymethacrylate-based polymer matrix in aqueous solutions of inorganic and organic acids, and 2) polymerizing complexes of anhydrous acids and prepolymers with organic plasticizer. The FT-IR spectra strongly suggest that the carbonyl groups in the polymer matrix interact with protons from the doped acids. High ionic (proton) conductivity in the range of $6\times10^{-4}-4\times10^{-2}\;S\;cm^{-1}$ was obtained at room temperature for the aqueous gels. The non-aqueous polymer complexes showed rather low ionic conductivity, but it was about $10^{-3}\;S\;cm^{-1}\;at\;70^{\circ}C$ for the $H_3PO_4$ doped polymer electrolyte. The mechanisms of ion (proton) conduction in the polymeric systems are discussed.

• 공업화학
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• 제32권4호
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• pp.467-471
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• 2021

본 연구에서는 가교성 작용기가 기능화된 사다리형 폴리실세스키옥산(LPMA64)을 합성하였고, 이를 액상 전해질의 열 가교 공정에 활용하여 유기-무기 하이브리드 겔 고분자 전해질을 제조하였다. 5 wt%의 낮은 LPMA64 고분자 가교제 함량으로도 전해질 내 네트워크 구조가 잘 발달하여, 우수한 형태 안정성과 높은 이온 전도도를 가지는 전해질의 제조가 가능하였다. 하이브리드 겔 고분자 전해질이 적용된 리튬-황 전지는 안정적인 율속과 장수명 성능 및 높은 쿨롱 효율을 나타냈으며, 이는 완화된 리튬 폴리설파이드 셔틀 현상에 기인했다. 본 연구결과는 제조된 유기-무기 하이브리드 겔 고분자 전해질이 리튬-황 전지 응용에 유망한 전해질임을 보여주었다.

• Macromolecular Research
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• 제16권3호
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• pp.247-252
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• 2008

Lithium gel electrolytes based on a mixed polymer matrix consisting of poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) and cyanoresin type M (CRM) were prepared using an in situ blending process. The CRM used in this study was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) (PVA) with a mole ratio of 1:1. The mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) with a volume ratio of 1:1. In this study, the presence of PVDF in the electrolytes helps to form a dimensionally stable film over a broad composition range, and decreases the viscosity. In addition, it provides better rheological properties that are suitable for the extrusion of thin films. However, the presence of HFP has a positive effect on generating an amorphous domain in a crystalline PVDF structure. The ionic conductivity of the polymer electrolytes was investigated in the range 298-333 K. The introduction of CRM into the PVDF-HFP/$LiPF_6$, complex produced a PVDF-HFP/CRM/$LiPF_6$ complex with a higher ionic conductivity and improved thermal stability and dynamic mechanical properties than a simple PVDF-HFP/$LiPF_6$, complex.