• Journal of Pharmaceutical Investigation
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• 제22권3호
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• pp.237-240
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• 1992

A series of biodegradable block copolymers consisting of $poly({\gamma}-benzyl\;L-glutamate)$ (PBLG) and poly(ethylene oxide) (PEO)-lactoselactone were prepared by polymerization of PEO-lactoselactone and ${\gamma}-benzyl$ L-glutamate-N-carboxyanhydride and characterized by IR and NMR. From circular dichroism measurements, it was found that the polymers exist in the ${\alpha}-helical$ conformation. Block copolymer microspheres were prepared by solvent-extraction-precipitation method for their primary evaluation for medical and biological applications.

• 한국염색가공학회지
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• 제5권3호
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• pp.194-205
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• 1993

Plasma polymerization in prepared glow discharge was carried out to improve the bathochromic of dyed PET fabrics by using silicon containing vinyl monomer in plasma polymerization equipment which consists of a pair of electrodes was connected to the 13.56MHz RF generator. The optimum condition for the bathochromic effect was investigated on various plasma polymeriztion parameters. By plasma polymerization used silicon containing vinyl monomer, the bathochromic of dyed PET fabrics was very enhanced. The optimum conditions on this equipment were as follows ; electrode distance : 3cm, discharge output : 60W, gas pressure : 0.3 Torr, monomer flow rate : 30㎤/min. plasma polymerization time : 60sec. The apparent strength of plasma polymerized PET fabrics was increased about 40∼47% with decreasing about 3 of L value.

• Macromolecular Research
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• 제17권3호
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• pp.174-180
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• 2009

Chemical modification of titanium/titanium oxide (Ti/$TiO_2$) substrates has recently gained a great deal of attention because of the applications of Ti/$TiO_2$-based materials to biomedical areas. The reported modification methods generally involve passive coating of Ti/$TiO_2$ substrates with protein-resistant materials, and poly(ethylene glycol) (PEG) has proven advantageous for bestowing a nonbiofouling property on the surface of Ti/$TiO_2$. However, the wider applications of Ti/$TiO_2$ based materials to biomedical areas will require the introduction of biologically active moieties onto Ti/$TiO_2$, in addition to nonbiofouling property. In this work, we therefore utilized surface-initiated polymerization to coat the Ti/$TiO_2$ substrates with polymers presenting the nonbiofouling PEG moiety and subsequently conjugated biologically active compounds to the PEG-presenting, polymeric films. Specifically, a Ti/$TiO_2$ surface was chemically modified to present an initiator for atom transfer radical polymerization, and poly(ethylene glycol) methacrylate (pEGMA) was polymerized from the surface. After activation of hydroxyl groups of poly(pEGMA) (pPEGMA) with N,N'-disuccinimidyl carbonate, biotin, a model compound, was conjugated to the pPEGMA films. The reactions were confirmed by infrared spectroscopy, X-ray photoelectron spectroscopy, contact angle goniometry, and ellipsometry. The biospecific binding of target proteins was also utilized to generate micropatterns of proteins on the Ti/$TiO_2$ surface.

• 폴리머
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• 제39권3호
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• pp.461-467
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• 2015

본 논문은 ferric p-toluenesulfonate를 산화제에 약 염기인 이미다졸과 poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) (PEG-PPG-PEG) 계면활성제를 동시 첨가하여 기상중합법으로 제조된 poly(3,4-ethylenedioxythiophene) (PEDOT) 박막의 광-전기적 특성 향상에 대한 것이다. 여러 가지 조건에서 제조된 PEDOT 박막 특성과 산화제의 첨가제로 사용된 약 염기와 계면활성제의 조합 효과의 상관관계를 규명하고자 하였다. 이미다졸과 PEG-PPG-PEG로 구성된 첨가제를 사용하여 제조된 PEDOT 박막은 $1300S{\cdot}cm^{-1}$ 이상의 전도성을 가졌다. PEG-PPG-PEG계 계면활성제의 분자량이 기상 중합을 이용한 PEDOT 박막의 특성에 미치는 영향도 조사하였다.

• 폴리머
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• 제31권6호
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• pp.550-554
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• 2007

최근 ATRP를 이용하여 단백질에 조절된 구조의 고분자를 연결시키는 연구가 활발히 진행되고 있다. 이때, ATRF 개시제는 단백질에 있는 일차아민에 아미드화 반응을 통하여 도입할 수 있다. 그런데, 형성되는 $\alpha$-할로 아미드의 경우, 상대적으로 늦은 개시 속도를 나타내는 것으로 알려져 있어 원하는 구조의 고분자를 얻는 것이 쉽지 않다. 따라서 본 연구에서는 아미드기를 가지고 있는 개시제를 이용한 [poly(ethylene glycol)methyl ether] methacrylate(PEGMA)의 ATRP 반응에 대한 적절한 반응 조건을 찾고자 하였다. PEGMA는 FEG를 가지로 가지는 단량체로서 고분자로 만들어졌을 때, 물에 잘 녹고 단백질과의 비특이적 상호작용이 적어 단백질과의 결합을 통한 바이오 응용에 널리 사용되고 있다. 아미드기를 가지는 개시제를 이용하여 PEGMA를 성공적으로 중합하기 위한 최적의 중합 조건은 할로겐 교환 반응과 활성 감소제를 사용해서 얻을 수 있었다.

• 폴리머
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• 제28권4호
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• pp.344-351
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• 2004

온도에 반응하는 고분자로서 폴리(에틸렌 글리콜)을 기본으로 다이블록 및 트리블록 폴리에스테르 공중합체들은 비독성과 생체적합성 그러고 생분해성 특징 때문에 주사제형의 약물전달체로서 많은 응용이 이루어지고 있다. 본 연구에서는 다이블록 공중합체를 이용한 새로운 솔-젤 전이 현상을 갖는 고분자를 준비하고자, 평균분자량 750g/mole의 메톡시 폴리(에틸렌 글리콜)과 카프로락톤을 실온에서 HCI $.$ Et$_2$O 존재 하에서 개환중합을 실시하였다. 합성된 고분자는 시차주사열량계와 X-선 회절기를 이용하여 특성을 분석하였고, 수용액상에서의 고분자 용액은 실온에서 신체온도로 온도를 상승시키면 졸에서 겔 상으로의 상변화를 보였다. 신체온도 부근에서의 겔 형성을 확인하기 위하여 20 W% 졸 상태의 고분자용액을 쥐의 피하에 주입한 결과 분산 없이 겔이 잘 형성되었고 2개월 간 겔이 유지됨을 확인하였다. 이러한 연구 결과로, 새로운 솔-젤 상전이 현상을 보이는 다이블록 공중합체를 합성하였고, 주사형 이식 재료로의 가능성을 확인하였다.

• Macromolecular Research
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• 제17권4호
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• pp.250-258
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• 2009

One-step seeded polymerization was used to prepare $7{\sim}10{\mu}m$ of crosslinked monodisperse spheres with four crosslinking agents using $4.68{\mu}m$ poly(methyl methacrylate)(PMMA) seed particles in aqueous-alcoholic media in the absence of the swelling process. The crosslinking agents used were ethylene glycol dimethacrylate(EGDMA), allyl methacrylate(AMA), 1,6-hexanediol diacrylate(HDDA) and trimethylolpropane trimethacrylate(TMPTMA). The effects of the type and concentration of the crosslinking agents on the swelling, pore size, thermal property of the networks and morphology of the particles were studied. The chemical structures and concentrations of the crosslinking agents affected both the swelling ratio and the porosity of the networks. In addition, the chemistry of the reactive vinyl group and chain length of the crosslinking agents affected the stability of the monodisperse particles of the ultimate morphology.

• Macromolecular Research
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• 제13권2호
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• pp.102-106
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• 2005

Poly(methyl methacrylate) (PMMA)/sodium montmorillonite (Na-MMT) nanocomposites were prepared with a novel method utilizing a macroazoinitiator (MAI). To induce the intergallery polymerization of methyl methacrylate (MMA), the MAI containing a po1y(ethylene glycol) (PEG) segment was intercalated between the lamellae of Na-MMT and swelled with water to enhance the diffusion of MMA into the gallery. The structure of the nanocomposite was examined using X-ray diffraction and transmission electron microscopy, and the thermal properties were examined using differential scanning calorimetry and thermogravimetry. The PMMA/Na-MMT nanocomposite prepared by intergallery polymerization showed a distinct enhancement of its thermal properties; an approximately $30^{\circ}C$ increase in its glass transition temperature and an $80\sim100^{\circ}C$ increase in its thermal decomposition temperature for a $10\%$ weight loss.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.226-226
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• 2006

Ethylene was polymerized with a catalyst having sterically hindered pentamethylcyclopentadienyl ligand, $Cp^{\ast}_{2}ZrCl_{2}/MAO$, and the polymerization mixture were treated with dry oxygen (oxidative workup) to produce hydroxyl-terminated polyethylenes (PE-OH). Polyethylene-block-Poly (${\Box}-caprolactone$) was synthesized from PE-OH and ${\cdot}\^{A}-caprolactone$A by using stannous octoate as a catalyst for ring opening polymerization of ${\cdot}\^{A}-caprolactone$. Polyethylene-block-Poly(methyl methacrylate) was obtained by transforming the hydroxyl-terminated polyethylenes to macroinitiators for atom transfer radical polymerization (ATRP) and by reacting them with MMA.

• Macromolecular Research
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• 제13권3호
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• pp.229-235
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• 2005

Various alkoxyamine initiators for nitroxide mediated radical polymerization (NMRP) were prepared in high yields by a simple substitution reaction of nitroxide anions with benzyl bromide. The required nitroxide anions were easily generated by treating either nitroxide free radicals or hydroxy amine with an alkali metal such as sodium or potassium in THF. This method is both practical and efficient, since the ionic conditions prevent other side reactions from occurring, such as the self-coupling or oligomerization reactions that are observed in the case of radical trapping conditions. To demonstrate the utility of the resulting alkoxyamine initiators, end- and telechelic-alkoxyamine PEG macroinitiators derived from the alkoxyamines were synthesized by a simple chemical modification, and used for the preparation of PEG-b-PS and PS-b-PEG-b-PS block copolymers by NMRP.