• 대한의용생체공학회:의공학회지
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• 제12권1호
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• pp.57-62
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• 1991

ABA type block copolymers composed of poly($\gamma-benzyl$ L-glutamate) (PBLG) as the A component and poly (ethylene glycol) as the B component were obtained by polymerization of $\gamma-benzyl$ L-gletamate N -carboxyanhydride, initiated by amino groups at both ends of poly(ethylene glycol) . From circular dichroism measurements in ethylene dichloride solution as well as from infrared spectTa measurements in solid state, it was found that the polypep- tide block exists in the a-helical conformation, as in PBLG homopolymer. $Poly-N^5$ (3-hydroxypropyl glutamine) (PHPG)/poly(ethylene glycol)block copolymer hydrogel was obtained by the treatment of PBLG/PBG block copolymer with the mixture of 3-ammine-1-propanol and diamlnooctane. The water content of PHPG/PEG block copolymer hydrogel was about 80wt% when the concentration of crosslinking agent was below 5 mole % per polymer.

• Fibers and Polymers
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• 제4권4호
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• pp.156-160
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• 2003

Poly(ethylene 2,6-naphthalate) (PEN)/Poly(ethylene glycol) (PEG) copolymers were synthesized by two step reaction during the melt copolymerization process. The first step was the esterification reaction of dimethyl-2,6-naphthalenedicarbox-ylate (2,6-NDC) and ethylene glycol (EG). The second step was the condensation polymerization of bishydroxyethylnaphthalate (BHEN) and PEG. The copolymers contained 10 mol% of PEG units with different molecular weights. Structures and thermal properties of the copolymers were studied by using $^1{H-NMR}$, DSC, TGA, etc. Especially, while the intrinsic viscosities of PEN/PEG copolymers increased with increasing molecular weights of PEG, but the glass transition temperature, the cold crystallization temperature, and the weight loss temperature of the copolymers decreased with increasing molecular weights of PEG. Consequently, the hydrophilicities by means of contact angle measurement and moisture content of the copolymer films were found to be significantly improved with increasing molecular weights of PEG.

• 멤브레인
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• 제25권6호
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• pp.515-523
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• 2015

상업적으로 이용되는 폴리스티렌계 이온교환막은 제조 공정이 쉽고 간단하지만 막이 가지는 취성 때문에 내구성이 약하다는 단점을 가지고 있다. 이를 보완하기 위하여 친수성 그룹인 poly(ethylene glycol)을 곁사슬로 가지고 있는 poly(ethylene glycol)methyl ether methacrylate를 공중합시켜 음이온 교환막을 합성하였다. 지지체로는 내화학성 및 기계적 강도가 우수한 다공성 PE 지지체를 사용하였고, 여기에 다양한 조성의 vinylbenzyl chloride, styrene, poly(ethylene glycol)methyl ether methacrylate, divinylbenzene, benzoyl peroxide를 녹인 단량체 용액을 지지체 기공에 채운 뒤 열중합 가교시켜 trimethylamine을 이용하여 음이온 교환기를 도입해 세공충전 음이온 교환막을 합성하였다. 또한 poly(ethylene glycol)methyl ether methacrylate의 곁사슬 길이와 각 단량체가 차지하는 비율의 변화가 음이온 교환막의 전기화학적 특성에 미치는 영향을 알아보았다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.13-16
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• 2001

최근 생분해성 고분자[1]의 유용성은 플라스틱 쓰레기의 처리에 관한 복합적인 문제점의 영향 때문에 많은 주목을 받고 있다 Aliphatic polyester는 생분해가능 혹은 퇴비로 사용 가능한 플라스틱 상품[2-4]의 용도로 가장 바람직한 구조를 가진 물질중의 하나이다. 이런 필요성의 대두로 poly(ethylene oxalate)(PEO)와 poly(butylene succinate)(PBS)[5-9]의 합성에 관해 많은 연구가 있었다. (중략)

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 춘계학술발표회 논문집
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• pp.64-68
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• 1996

PP-EVOH(poly(vinyl alchol-co-ethylene)) blends were prepared by the mixing of polypropylene and poly(vinyl alcohol-co-ethylene) containing 38mol% of ethylene units (EVOH38) at melt state above PP melting temperature. The materials were characterized by using dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and contact angle measurement to detemine the glass transition, meltin, decomposition temperatures, and wettability respectively. From the results, PP-EVOH(poly(vinyl alcohol-co-ethylene)) blends exgibits partial miscibility.

• Macromolecular Research
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• 제16권7호
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• pp.659-662
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• 2008

A new and useful poly(ethylene oxide)-based pH-sensitive block copolymer is introduced. Poly(ethylene oxide-b-N-phenylmaleimide) was first synthesized by anionic polymerization of N-phenylmaleimide (N-PMI) using mixed alkali metal polymeric alkoxide by sequential monomer addition method in the mixture of benzene/THF/DMSO (10/5/3, v/v/v) at room temperature. Reductive deimidation of the resulting block copolymer was performed using hydrazine monohydrate leading to the formation of the corresponding pH-sensitive poly(ethylene oxide-b-maleic acid).

• 청정기술
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• 제8권1호
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• pp.39-44
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• 2002

Poly(ethylene terephthalate)의 재활용을 위하여 촉매가 없는 상태에서 고온, 고압에서의 메탄올 분해에 의한 dimethyl terephthalate와 ethylene glycol의 회수에 관한 연구가 진행되었다. 과량의 메탄올 존재 하에서 반응기를 62기압, $310^{\circ}C$에서 약 50분간 반응시키면 98% 이상의 높은 수율의 dimethyl terephthalate가 얻어져 기존의 방법보다 간편하며 경제적인 방법으로 재활용의 새로운 방법으로 제안되었다.

• 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.

• Korea-Australia Rheology Journal
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• 제11권3호
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• pp.219-223
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• 1999

The effects of the transreactions on the rheological properties have been found in the poly(ethylene 2, 6-naphthalate) (PEN) and poly (ethylene terephthalate) (PET) blends. The rheological properties were very much dependent on the blend compositions, which, in turn, were related to extent of the reactions. In particular, a blend with 50/50 wt% composition exhibits an unusual and remarkable decrease in complex viscosity and it may be related to the randomness of the copolymer structure through transreactions. It has been identified by investigating the extent of transreactions and block length of the copolymer from the (ethylene 2, 6-naphthalate) (EN) and (ethylene terephthalate) (ET) units from $^1{H}$ n.m.r. spectra.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.408.2-409
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• 2002

The aim of this study is to prepare biodegradable microspheres without use of any kind of surfactants or emulsifiers for a novel sustained delivery carriers of protein drugs. Poly(e-caprolactone)/poly(ethylene glycol)/poly(e-caprolactone) (CEC) triblock copolymer was synthesized by ring-opening of e-caprolactone with dihydroxy poly(ethylene glycol) and was used to make surfactant-free microspheres. (omitted)