• 폴리머
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• 제26권6호
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• pp.710-717
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• 2002

주형분자로서 all-trans-retinoic acid를 사용하여 methacrylic acid (MAA)를 가교 중합함으로써 분자각인고분자를 제조하였다 제조된 분자각인고분자가 충전된 HPLC컬럼의 분리특성을 살펴본 결과 레티노이드 유도체에 대해 좋은 분리 특성을 보였다. 주형분자의 양이 일정할 경우 주형분자대비 MAA의 양이 증가할수록 컬럼의 성능인자와 선택도는 높게 나타났으며, 이는 확률적으로 보다 많은 호스트분자와 주형분자간의 결합소를 제공한데 따른 결과이다. 유화중합에 의해 제조된 분자각인 고분자입자는 둥근 형태로 관찰되었으며 그 크기도 용액중합에 의해 제조된 것에 비해 훨씬 일정하게 분산되었으나, 분리특성은 효율이 떨어짐을 알 수 있었다 이러한 이유는 유화중합에 의한 분자각인고분자 제조시 물과 MAA 또는 물과 주형분자간의 수소결합에 의해 MAA와 주형분자간의 결합력 및 결합소의 수에 손실이 있었기 때문이다.

• Bulletin of the Korean Chemical Society
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• 제17권4호
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• pp.376-379
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• 1996

The bulk photopolymerization of methacrylic acid (MA) with phenylsilane was performed to produce poly(MA)s containing phenylsilyl moiety presumably as an end group. It was found that while the polymerization yields and intrinsic viscosities decreased, the TGA residue yields and the relative intensities of SiH IR stretching bands increased with increasing molar ratio of phenylsilane over MA. The phenylsilane seemed to significantly influence on the photopolymerization as both chain initiation and chain transfer agents.

• Journal of Pharmaceutical Investigation
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• 제41권2호
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• pp.111-115
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• 2011

pH-sensitive cross-linked polymeric micelles were synthesized by using block ionomer complexes of poly(ethylene oxide)-b-poly(methacrylic acid) (PEO-b-PMA) with calcium ions as micellar templates. An anticancer drug, doxorubicin (DOX) was conjugated on the cross-linked ionic cores of micelles via acid-labile hydrozone bonds. The resulting DOX-conjugated, pH-sensitive micelles are stable at physiological conditions, whereas the release of DOX was significantly increased at the acidic pH. Such micelles were internalized to lysosomes, and acidic pH in lysosomes triggers the release of DOX upon internalization in MCF-7 breast cancer cells. The released DOX entered the cell nucleus and eventually killed cancer cells. Therefore, these data demonstrate that the pH-sensitive micelles could be a promising nanocarrier for delivery of anticancer drug, DOX.

• Macromolecular Research
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• 제13권4호
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• pp.327-333
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• 2005

pH-sensitive hydrogels were studied as a drug carrier for the protection of insulin from the acidic environment of the stomach before releasing it in the small intestine. In this study, hydrogels based on poly(ethylene oxide) (PEO) networks grafted with methacrylic acid (MAA) or acrylic acid (AAc) were prepared via a two-step process. PEO hydrogels were prepared by ${\gamma}-ray $ irradiation (radiation dose: 50 kGy, dose rate: 7.66 kGy/h), grafted by either MAA or AAc monomers onto the PEO hydrogels and finally underwent irradiation (radiation dose: 520 kGy, dose rate: 2.15 kGy/h). These grafted hydrogels showed a pH-sensitive swelling behavior. The grafted hydrogels were used as a carrier for the drug delivery systems for the controlled release of insulin. Drug-loaded hydrogels were placed in simulated gastric fluid (SGF, pH 1.2) for 2 hr and then in simulated intestinal fluid (SIF, pH 6.8). The in vitro drug release behaviors of these hydrogels were examined by quantification analysis with a UV-Vis spectrophotometer.

• Korean Membrane Journal
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• 제9권1호
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• pp.57-63
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• 2007

Amphiphilic graft copolymer from poly(vinylidene fluoride) (PVDF) was synthesized using atom transfer radical polymerization (ATRP) for composite nanofiltration membranes. Direct initiation of the secondary fluorinated site of PVDF facilitates grafting of tert-butyl methacrylate (tBMA). Amphiphilic PVDF-g-PMAA graft copolymer with a 51:49 wt ratio was obtained by hydrolyzing poly(tert-butyl methacrylate) (PtBMA) to poly(methacrylic acid) (PMAA). Wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) confirmed the decrease of crystallinity of PVDF upon graft copolymerization. Composite nanofiltration membranes were prepared from PVDF-g-PMAA as a top layer coated onto PVDF ultrafiltration (UF) support membrane. The morphology and hydrophilicity of membranes were characterized using scanning electron microscopy (SEM) and contact angle measurement. The rejections of composite membranes were 80.2% for $Na_2SO_4$ and 28.4% for NaCl, and the solution flux were 9.5 and $14.5\;L/m^2\;h$ at 1.0 MPa pressure.

• Elastomers and Composites
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• 제48권4호
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• pp.294-299
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• 2013

수용성 단량체인 메타크릴산 (MAA)을 단량체로 potassium persulfate (KPS)를 개시제로 이용하여 $70^{\circ}C$에서 $90^{\circ}C$ 사이의 선택된 온도에서 용액중합을 진행하였다. 물에 대한 메타크릴산의 농도가 감소하거나 개시제의 농도가 증가하면 분자량은 감소하였다. 중합반응온도는 폴리메타크릴산 (PMAA)의 분자량에 크게 영향을 미치지 않았다. Weissenberg 효과는 대부분의 반응온도에서 나타났으며, $90^{\circ}C$에서는 약하게 관찰되었다. 대부분의 중합반응에서 분산성지수는 1.5 이하로 관찰되었다. 교반속도가 증가하면서 분자량은 점진적으로 증가하다, 교반속도가 800 rpm에 이르면서 수평균 및 중량평균분자량이 동일하게 791,000 g/mol의 분자량을 갖는 단분산성의 PMAA가 구하여졌다. 유리전이온도는 $162^{\circ}C$로 측정되었다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1990년도 제2차 학술발표초록집
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• pp.12-12
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• 1990

• Bulletin of the Korean Chemical Society
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• 제17권6호
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• pp.532-535
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• 1996

The bulk photopolymerization of methacrylic acid (MA) with secondary silanes such as PhMeSiH2 and Ph2SiH2 gave poly(MA)s possessing the secondary silyl moiety presumably as an end group. It was found that while the polymerization yields and intrinsic viscosities decreased, the TGA residue yields and the relative intensities of SiH IR stretching bands increased with increasing mole ratio of the secondary silane over MA. The sterically less bulky silane PhMeSiH2 produced poly(MA)s with somewhat higher molecular weights and with similar TGA residue yields compared with the sterically bulkier silane Ph2SiH2. The secondary silanes seem to significantly influence on the photopolymerization of MA as both chain initiation and chain transfer agents.

• Archives of Pharmacal Research
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• 제26권8호
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• pp.649-652
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• 2003

Polymeric nanoparticles composed of polystyrene (PS) as core and poly(methacrylic acid) (PMA) as corona were prepared by the dispersion copolymerization. The potential of the nanoparticles as carriers for recombinant human epidermal growth factor (EGF) was investigated. The nanoparticles showed monodispersity and good water-dispersibility. The loading content of EGF to the nanoparticles was very high due to electrostatic interaction between EGF and nanoparticles. EGF was released as a pseudo-zero order pattern after initial burst effect. The nanoparticles were sufficient for A431 cells proliferation.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2004년도 추계학술발표회 논문집
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• pp.273-273
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• 2004