• Membrane Journal
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• v.23 no.4
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• pp.283-289
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• 2013

Poly(vinyl alcohol) (PVA) coating solution containing glutaraldehyde (GA) and maleic anhydride (MA) as crosslinking agents was coated onto hydrolyzed poly acrylonitrile (PAN) hollow fiber membranes. The permselectivities of the resulting composite membranes prepared varying the reaction temperature and the concentration of the crosslinking agents were tested for 90 wt% ethanol aqueous mixtures by the pervaporation technique at $60^{\circ}C$. In general, the flux decreased while the selectivity increased for the increases of the reaction temperature and the crosslinking concentration. In case of GA as a crosslinking, the flux $165g/m^2hr$ and the separation factor 81 were obtained at GA 11 wt% and the reaction temperature $120^{\circ}C$. And for the case of MA, the flux $174g/m^2hr$ and the separation factor 73 were obtained at MA 11 wt% and the reaction temperature $120^{\circ}C$.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1582-1584
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• 2008

This paper reports a simple fabrication method for creating the superhydrophobic polymer surface using a plasma etching. Generally, it is necessary for the superhydrophobic surfaces to have a rough structure on surface with the composition of the low surface energy. In this study, Poly(methyl methacrylate) (PMMA), poly(ethylene terephthalate) (PET), acrylonitrile butadiene styrene (ABS) with superhydrophobic surface were fabricated using $O_2$ plasma etching and vapor deposition with the fluoroalkylsilane self-assembled monolayers. The plasma treated polymer surfaces are covered with the nano-pillar shaped structures after treatment for $1{\sim}2min$. And these samples with FOTS SAMs coating are showed the superhydrophobicity having the water contact angle of around $150^{\circ}$ and sometimes around $180^{\circ}$ depending on the treatment time. Furthermore the nanostructured polymer is transparent for the visible light.

• Applied Chemistry for Engineering
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• v.2 no.2
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• pp.147-154
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• 1991

Thermogravimetric measurements have been carried out to investigate the stabilization and carbonization of copolymer of acrylonitrile(95 wt %) and methyl acrylate(5 wt %) at various heating rates. The cyclization and dehydrogenation during the stabilization were important factors to determine pore development in the carbonization process. The pore and the specific surface area during the carbonization began to develope at the temperature higher than $400^{\circ}C$.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.362-370
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• 1996

The performance of The performance of $Li/V_6O_{13}$ cell and the electrochemical properties of polymer electrolyte based on poly(acrylonitrile)[PAN] was investigated. The ionic conductivity of polymer electrolyte showed $2.3{\times}10^{-3}S/cm$ and the compatibility with lithium electrode was excellent. Also, it showed the electrochemical stability up to 4.3V(vs. $Li^+/Li$). The cell reaction of $Li/V_6O_{13}$ was dominated by the interfacial resistance between $V_6O_{13}$ electrode and polymer electrolyte. The diffusion coefficient of lithium ion within $V_6O_{13}$ was $2.7{\times}10^{-9}{\sim}4.2{\times}10^{-8}cm^2/sec$. The utilization of $V_6O_{13}$ active material was 95% at C/8($50{\mu}A/cm^2$) and 82% at C/4($100{\mu}A/cm^2$), respectively.

• Macromolecular Research
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• v.11 no.6
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• pp.410-417
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• 2003

Poly(methyl methacrylate-co-acrylonitrile) [P(MMA-co-AN)]/Na-MMT nanocomposites were synthesized through emulsion polymerization with pristine Na-MMT. The nanocomposites were exfoliated up to 20 wt% content of pristine Na-MMT relative to the amount of MMA and AN, and exhibited enhanced storage moduli, E', relative to the neat copolymer. The exfoliated morphology of the nanocomposite was confirmed by XRD and TEM. 2-Acryla-mido-2-methyl-1-propane sulfonic acid (AMPS) widened the galleries between the clay layers before polymerization and facilitated the comonomers, penetration into the clay to create the exfoliated nanocomposites. The onset of the thermal decomposition of the nanocomposites shifted to a higher temperature as the clay content increased. By calculating areas of tan$\delta$ of the nanocomposites, we observed that the nanocomposites show more solid-like behavior as the clay content increases. The dynamic storage modulus and complex viscosity increased with clay content. The complex viscosity showed shear-thinning behavior as the clay content increased. The Young's moduli of the nano-composites are higher than that of the neat copolymer and they increase steadily as the silicate content increases, as a result of the exfoliated structure at high clay content.

• Macromolecular Research
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• v.15 no.4
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• pp.308-314
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• 2007

The effects of a compatibilizer on polypropylene (PP)/poly(acrylonitrile-butadiene-styrene) (ABS) blends were studied. Blends of the PP/ABS, with PP-g-SAN copolymer as a compatibilizer, were prepared using a twin screw extruder. The flexural and impact strength of the PP/ABS blends with the PP-g-SAN copolymer increased significantly with PP-rich compositions on the addition of the PP-g-SAN copolymer at 3 phr. The increase in the mechanical properties of the PP/ABS/PP-g-SAN blend may have been due to the toughening effects of the ABS in the PP-rich compositions. In the morphology study of the PP/ABS/PP-g-SAN (80/20) blend with the PP-g-SAN copolymer, the minimum droplet size, $5.1{\mu}m$, was observed with the addition on phr of the PP-g-SAN copolymer. The complex viscosity of the PP/ABS/PP-g-SAN (80/20) blends increased with the addition of3 phr of the PP-g-SAN copolymer. From the above mechanical properties, morphology and complex viscosity results for the PP/ABS blends, it is suggested that the compatibility is more increased with the PP-rich composition (PP:ABS=80/20 wt%) of the PP/ABS blend on the addition of 3 phr of the PP-g-SAN copolymer.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.65-73
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• 2017

Purpose 3D 프린팅 기술은 3D 스캔이나 모델링을 통하여 적측가공 방식으로 제작하는 기공기술로서 금형 없이 직접 생산이 가능하고 빠른 시간 내에 제작이 가능하여 최근 다양한 산업분야에서 본격적으로 적용되고 있다. 3D 프린팅 기술은 의료분야에 있어, 영상의학 및 방사선 치료분야에서 다양하게 활용되고 있지만 핵의학 분야에서는 관련 연구가 미비한 실정이다. 그러므로 본 연구는 기존에 적용되고 있는 핵의학분야 팬텀과 3D 프린팅 기술로 제작된 텀의 특성을 비교하고 적용 가능성을 평가하는데 목적을 두었다. Materials and Methods 방사선 투과도 변화측정 국제기준 팬텀인 알루미늄(Aluminum) 계단 쐐기(step wedge)를 기준($140mm{\times}62mm{\times}35mm$)으로 PMMA(Poly Methyl Meta Acrylate)와 ABS(Acrylonitrile Butadiene Styrene)재질로 각각 동일한 크기의 팬텀을 제작하였다. PMMA 팬텀은 핵의학 분야에서 주로 적용되는 팬텀의 성분과 동일한 소재로 제작하였고, ABS 팬텀 제작은 3D 프린팅 기술의 액체 기반형의 SLA(Stereo Lithography Apparatus)기법을 사용하여 제작하였다. 본 연구는 SPECT/CT장비 BrightView XCT(Philips Health Care, Cleveland, USA)를 이용하였다. 영상 획득은 Rectangular Flood phantom(Biodex, New York, USA) $^{99m}TcO_4$ 3, 6 mCi와 $^{57}Co$ lood phantom(adqual, New Hampshire, USA) $^{57}Co$ 20 mCi를 이용하여 Aluminum, PMMA, ABS 팬텀에 대해 60 min 리스트모드(List mode)로 획득하였다. 획득한 영상의 분석을 위해 관심영역(ROI)을 설정하여 각 팬텀의 단계별로 평가하였다. Results 방사선원의 종류 및 방사선량에 따라 ABS 팬텀의 계수치는 PMMA 팬텀의 계수치와 유사한 값을 나타내며, 두께의 증가에 따라 선형적으로 감소하였다. Aluminum, PMMA, ABS 팬텀의 선감약계수를 비교했을 때, Aluminum 팬텀의 선감약계수는 나머지 두 팬텀보다 수치가 높았고, PMMA, ABS 팬텀에서는 근사치의 선감약계수가 나타났다. Conclusion 3D 프린팅 기술로 제작된 ABS 팬텀을 기준으로 PMMA 팬텀은 두께가 증가함에 따른 계수치의 변화가 유사하게 선형적으로 감소하였고, 선감약계수도 근사치로 나타내었다. ABS 팬텀의 핵의학적 적용 가능성을 확인할 수 있었으며, 추후 연구를 통해 세부적인 교정치(correction value)를 적용한다면 활발한 적용이 가능하리라 사료된다.

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.169-172
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• 2000

A new gel polymer electrolyte based on the modified polyacrylonitrile (PAN), polyacrylonitrile-co-bis[2-(2-methoxyethoxy)ethyl]itaconate (abbreviated as PANI) copolymer was synthesized in expectation of enhanced trapping ability of liquid electrolytes. PAN and PANI blend was complexed with organic solvents, ethylene carbonate (EC) and dimethyl carbonate (DMC), and $LiClO_4$ salt. The highest room temperature conductivity of $2\times10^{-3}\;Scm^{-1}$ was found for a film of 25PAN+10PANl+50EC/DMC+$15LiClO_4$. The solvent-rich crystalline part decreases due to the blending of PANI and therefore number of charge carriers increases giving higher ionic conductivity. The addition of PAM as a host polymer in the PAN-based gels has beneficial effects such as higher ionic conductivity, better thermal characteristics, better miscibility with solvent, wider electrochemical stability, and better interfacial stability with lithium electrode, though it exhibits slightly less mechanical rigidity.

• Polymer(Korea)
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• v.38 no.1
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• pp.103-107
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• 2014

Poly(acrylonitrile-butadiene-styrene) (ABS) composite sheets containing titanium dioxide ($TiO_2$), barium sulfate ($BaSO_4$), calcium carbonate ($CaCO_3$) were prepared by using a co-rotating twin screw extruder, and the reflectance and flexural modulus of the composite sheets were measured. The fillers were well dispersed in ABS matrix. The reflectance of composite sheet was increased with increasing $TiO_2$ and $BaSO_4$ content. Sheet having $TiO_2$ 20 wt% composition, with 5~20 wt% $BaSO_4$ resulted in more than 95% of reflectance. The flexural modulus of composite sheet was increased from 1864 MPa for $ABS/TiO_2/BaSO_4$ 85/10/5 (w/w/w) to 3134 MPa for $ABS/TiO_2/BaSO_4$ 55/20/25 (w/w/w).

• Membrane Journal
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• v.29 no.3
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• pp.164-172
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• 2019

In this work, we demonstrate a facile process to prepare an electrolyte membrane for the supercapacitor based on a graft copolymer consisting of starch and poly(acrylonitrile) (PAN). The graft copolymer (starch-g-PAN) was synthesized via free radical polymerization initiated by ceric ions. The starch-g-PAN was dissolved in ionic liquid, i.e. 1-ethyl-3-methylimidazolium dicyanamide (EMIM DCA) without any organic solvents at room temperature. The gelation of polymer electrolyte membranes occurred by applying high temperature, i.e. $100^{\circ}C$ for 1 hour. The resultant electrolyte membrane was flexible and thus applied to flexible solid supercapacitors. The performance of the supercapacitor based on starch-g-PAN graft copolymer electrolyte reached 21 F/g at a current density of 0.5 A/g. The cell also showed high cyclic stability with 86% of retention rate within 10,000 cycles. The preparation of starch-g-PAN based polymer electrolyte membrane provides opportunities for facile fabrication of flexible solid supercapacitors with good performance.