• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.327-330
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• 1996

Poly(L-leucine)(PLL)/poly(ethylene oxide)(PEO)/poly (L-leucine)(PLL) block copolymers were synthsized by polymerization of L-leucine N-carboxyanhydride with diamine-terminated PEO for possibility of wound dressing which may have several advantages such as 1) increase of solubility, 2) control of biodegradation, 3) absorption of body fluid. 4) non-immunogenic effect than PLL homopolymer wound dressing aleady commercialized. Water content increased with an increase of PEO content in the block copolymer due to the hydrophilicity of PEO. Release of silver sulfadiazine(AgSD) from AgSD loaded wound dressing increased with an increase of PEO content in the block copolymer. It was found that the number of Pseudomonas aeruginosa decrease with an increase of PEO content due to the fast release of antibacterial agents with an increase of PEO content in the block copolymer.

• Bulletin of the Korean Chemical Society
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• 제15권9호
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• pp.748-751
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• 1994

Poly(ethylene oxide) (PEO) in aqueous solutions has a hydrophobic character which can induce the hydrophobic interaction between its nonpolar parts. The hydrophobic properties of aqueous PEO solutions are studied by the viscometry in terms of the water structure-making and -breaking capabilities of added solutes of ureas. The results show that the contracted conformation of PEO of low molecular weight, namely poly(ethylene glycol) (PEG), does not result from the hydrophobic interaction between the nonpolar parts of PEO but it can participate in a hydrophobic interaction between the nonpolar parts of PEO and added ureas solutes with nonpolar groups, which can induce a large hydrodynamic volume and increase the viscosity. On the other hand, the PEO of large molecular weight seems to behave like any other water soluble polymers with nonpolar parts and its conformation in aqueous solutions is well explained in terms of water structure perturbing capabilities of added ureas.

• 대한의용생체공학회:의공학회지
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• 제27권5호
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• pp.224-228
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• 2006

The object of this study is to investigate the potential of dual-electrospun polymer based structure for vascular tissue engineering, especially for the medium or small sue blood vessels. Polyurethane(PU), which is known to be biocompatible in this area, was electrospun with poly(ethylene oxide) (PEO). Concentration of PU was fixed at 20wt%, while that of PEO was set from 15 to 35wt%. Morphological features were observed by SEM image and measurement of porosity and cellular responses were tested before and after extracting PEO from the hybrid scaffolds by immersing the scaffolds into distilled water. The diameter of PEO fibers were ranged from 200nm to 500nm. The lower concentration of PEO tended to show beads. The porosity of the scaffolds after extracting PEO was highly increased with higher concentration of PEO as expected. Also, higher proliferation rate of smooth muscle cells was observed at higher concentration of PEO than at the lower concentration and without PEO. As conclusions, this dual electrospinning technique combined with PU and PEO is expected to overcome the current barrier of cell penetration by providing more space for cells to proliferation.

• E2M - 전기 전자와 첨단 소재
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• 제8권4호
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• pp.487-494
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• 1995

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li secondary battery. We investigated the effects of lithium salts, plasticizer addition, temperature dependence of conductivity and electrochemical stability window of polyethylene oxide(PEO) electrolytes. PEO electrolyte completed with LiCIO$\_$4/ shows the better conductivity than the others. PEO-LiCIO$\_$4/ electrolyte, when EO/Li$\^$+/ ratio is 8, showed adequate conductivity around room temperature. By adding propylene carbonate and ethylene carbonate to PEO-LiCIO$\_$4/ electrolyte, its conductivity was higher than that of PEO-LiCIO$\_$4/ without those. Also PEO$\_$8/LiCIO$\_$4/ electrolyte remains stable up to 4.5V vs. Li/Li.

• Journal of Pharmaceutical Investigation
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• 제22권4호
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• pp.323-326
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• 1992

$Poly({\varepsilon}-carbobenzoxy\;L-lysine)/poly(ethylene oxide)/poly({\varepsilon}-carbobenzoxy\;L-lysine)$ (LEL) block copolymers containing $poly({\varepsilon}-carbobenzoxy\;L-lysine)$ (PCLL) as the A component and poly(ethylene oxide) (PEO) as the B component were investigated as drug delivery matrix. PCLL homopolymer and LEL block copolymer microspheres containing anticancer drug, cytarabine, were prepared by a solvent evaporation process and the release patterns of cytarabine from the microspheres were investigated in vitro. The size of PCLL homopolymer and LEL block copolymer microspheres was ranged from $0.2\;{\mu}m$ to $1\;{\mu}m$ in diameter and the shape of the microspheres was almost round. The release pattern of cytarabine from the block copolymer microspheres was dependent on the mole % of PEO of the block copolymers.

• 멤브레인
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• 제27권4호
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• pp.313-318
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• 2017

올레핀/파라핀 분리를 위해 $Poly(ethylene oxide)(PEO)/AgBF_4/Al(NO_3)_3/Ag_2O$ 복합막이 제조되었으며, $Ag_2O$가 도입되었을 때, 복합체 분리막의 초기성능은 선택도 13.7과 투과도 21.7 GPU로 관찰되었다. $PEO/AgBF_4/Al(NO_3)_3$ 분리막의 성능(선택도 13와 투과도 7.5 GPU)에 비해서 초기성능이 증가한 이유는 $Ag_2O$의 첨가로 인한 Ag ion의 활성도 증가로 생각되었다. 하지만 시간에 따른 성능저하 현상이 관찰되었는데 이는 고분자 matrix인 PEO 때문인 것으로 생각되었다. PEO 고분자는 $Ag_2O$ 입자를 안정화 시킬 수 없기 때문에 용매가 증발하면서 $Ag_2O$ 입자끼리 뭉치게 되고, $Ag_2O$가 barrier 역할을 하게 돼서 시간이 지나면 투과도가 감소하는 것으로 분석되었다.

• 공업화학
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• 제7권3호
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• pp.433-442
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• 1996

분자량이 큰 Poly(ethylene oxide)[PEO] 고분자에 $LiClO_4$, $LiCF_3SO_3$ 등의 리튬염과 ethylene carbonate(EC), propylene carbonate(PC) 등의 가소제를 고정화시킨 고분자 전해질의 전기화학적 특성 및 물리적 성질을 조사하였다. 가소제가 첨가된 PEO-Li계 고분자 전해질은 상온에서 $10^{-4}S/cm$의 이온 전도도를 보였고 4.5 V(vs. $Li^+/Li$)까지 높은 전기화학적인 안정성을 나타냄으로써 리튬 2차전지에 적용 가능한 것으로 나타났다. 리튬염 및 가소제의 첨가에 따라 PEO의 결정상이 감소되었고 특히 $LiClO_4$, PC등이 $LiCF_3SO_3$, EC 등에 비하여 더 효과적인 것으로 나타났다. 리튬염의 농도가 증가할수록 고분자 전해질의 유리전이온도($T_g$)는 증가되었으며 반면에 융점온도($T_m$)는 감소하는 것으로 나타났다. 가소제가 첨가된 고분자 전해질은 $6^{\circ}C$에서 결정화 되었다.

• 폴리머
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• 제27권5호
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• pp.449-457
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• 2003

액중건조법을 사용하여 PCL/PEO 마이크로캡슐을 제조하여 형태적 분석 및 제조 조건에 따른 특성을 살펴보고 거동을 통하여 약물 전달 체계로서의 가능성을 고찰하였다. 유화제의 종류 및 농도 그리고 교반 속도에 따른 마이크로캡슐의 입경과 형태의 변화에 대하여 광학 현미경과 SEM을 사용하여 관찰하였다. 또한 접촉각 측정을 통해 PCL/PEO와 약물간의 계면에서의 부착일을 살펴보았으며, 방출 거동을 알아보기 위해 UV/vis. 흡광 광도법으로 흡광도를 측정 하여 용출된 약물의 양을 정량하였다. 그 결과, 마이크로캡슐의 평균 입경이 170 nm∼68 $\mu$m인 구형의 형태를 나타내었으며, PEO의 함량이 증가함에 따라 친수성기가 증가하여 물에 대한 부착일이 증가함을 알 수 있었다. 또한 약물 방출 실험을 통하여 PEO의 함량을 높게 하고 교반 속도를 빠르게 하여 제조한 마이크로캡슐의 약물 방출이 상당히 빠름을 알 수 있었다 이는 PEO의 함량이 증가함에 따라 친수성기가 증가하고 계면력이 증가하기 때문이라 사료된다.

• 폴리머
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• 제25권6호
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• pp.759-764
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• 2001

폴리에틸렌옥사이드 (PEO)의 고유한 성질인 결정성을 저하시키기 위하여 카보네이트 관능기가 도입된 새로운 PEO 유도체를 제조하였다. 이를 위하여 다양한 분자량의 폴리에틸렌글리콜 (PEG)과 디메틸카보네이트 (DMC)로부터 에스터 교환반응에 의하여 메틸카보네이트 관능기가 PEE 말단에 존재하는 전구체를 우선 합성하였으며, 촉매로는 황산을 사용하였다. 얻어진 전구체를 이용하여 진공하에서의 축합 반응을 통하여 PEO 주사슬에 카보네이트 관능기가 도입된 새로운 PEO 유도체, poly(ethylene oxide-carbonate)s를 합성하였으며, 이 때 titanium isopropoxide (TiP)를 촉매로 사용하였다. 반응에 이용한 PEG는 수평균 분자량이 200, 400 그리고 600 g/mol인 것을 사용하였으며, 합성된 새로운 유도체의 구조와 조성을 $^1H-NMR$과 $^{13}C-NMR$로 확인하였으며, 그들의 열적 특성 및 분자량을 DSC, TGA 및 GPC를 이용하여 분석하였다.

• 한국염색가공학회지
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• 제21권5호
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• pp.16-20
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• 2009

Films of Poly(ethylene oxide), PEO, were modified to impart hydrophilicity via UV irradiation. The UV irradiation treatment produced new photo-oxidized groups of carbonyl and ether groups as indicated in ATR and ESCA analysis. It was found that water contact angle decreased from $15^{\circ}C$ to $10^{\circ}C$ and total surface energy of PEO increased from 54.2 mN/m to 76.6 mN/m with increasing UV energy, which was attributed to significant contribution of acid base interaction of the photo-oxidized PEO rather than nonpolar interaction originating from the dominant increase in Lewis acid parameter. The increased hydrophilicity and surface energy were also proved by the decreased water wetting time.