• 제목/요약/키워드: photopoly-merization

검색결과 3건 처리시간 0.015초

Syntheses and Optical Properties of Cholesteric Liquid Crystal Polymers Utilizing p-Phenylene Bis-(p-(3-acryloxy-2-methylpropyloxy)benzoate

  • 윤웅찬;최정희;진성호;송동미
    • Journal of Photoscience
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    • 제12권1호
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    • pp.41-46
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    • 2005
  • We synthesized chiral choleseric liquid crystalline monomer p-phenylene bis-(p-3-acryloxy-2(S)-methylpropoxy)benzoate (1) and achiral nematic liquid crystalline monomer, p-phenylene p-acryloxy-6-hexyloxy-p-octyloxybenzoate (2) for the construction of cholesteric polymer network with a pitch gradient. In this research we attempted to synthesize cholesteric polymer film which have a wide reflection bandwidth in the region of visible wavelength with the synthesized chiral cholesteric monomer 1 and nematic monomer 2 under various photopoly merization conditions. We succeeded to construct cholesteric polymer film network with a pitch gradient covering more than 200 nm bandwidth in the visible wavelength by diffusion controlled photostructuring method.

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Synthesis and Antitumor Activity of Phthalimide-Based Polymers Containing Camptothecin

  • Lee, Neung-Ju
    • Macromolecular Research
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    • 제11권1호
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    • pp.47-52
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    • 2003
  • The objective of this study was to develop a polymeric drug delivery system for camptothecin (CPT), capable of improving its therapeutic index and reducing its side effects. A monomeric conjugate, 3,6-endo-methylene-1,2,3,6-tetrahydrophthalimidoethanoylcamptothecin in (ETECPT) between CPT and 3,6-endo-methylene-1,2,3,6-tetrahydrophthalimidoethanoic acid was synthesized. Its homo-and copolymer with acrylic acid (AA) were prepared by photopolymerization using 2,2-dimethoxy-2-phenylacetophenone (DMP) as a photoinitiator. The monomer and its polymers were characterized by IR, $^1$H- and $^{13}$ C-NMR spectra. The ETECPT content in poly(ETECPT-co-AA) obtained by elemental analysis was 82 wt%. The number-average molecular weights of the polymers determined by gel permeation chromatography were as follows: M$_{n}$ = 11,400 for poly(ETECPT), M$_{n}$ = 17,900 for poly(ETECPT-co-AA). The $IC_{50}$/ values of ETECPT and its polymers against cancer cells were much larger than that of CPT. Our results from the in vivo antitumor activity indicated that all polymers show high antitumor activity than CPT at a dose of 100 mg/kg./kg.

Poly(ethylene glycol)diacrylate/poly(propylene glycol)diacrylate 막의 이산화탄소 기체 투과특성에 관한 연구 (Gas Permeation Properties of $CO_2$ Through Poly(ethylene Glycol) Diacrylate/Poly(Propylene Glycol) Diacrylate Membrane)

  • 임지원;남상용;이선용;윤태일
    • 멤브레인
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    • 제14권3호
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    • pp.250-257
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    • 2004
  • 이산화탄소 분리에 이용하기 위하여 PEG (Poly(ethylene glycol)diacrylate)와 PPG (Poly(propylene glycol) diacrylate)를 광학 중합반응(Photopoly merization)을 이용하여 제조하였다. PEG와 PPG는 분자량이 각각 258과 540이었다. PEG와 PPG의 질량 혼합비(wt%)를 9:1, 8:2, 7:3, 6:4, 5:5로 변화시키면서 막을 제조하였다. $25^{\circ}C$에서 PEG/PPG (9:1)의 이산화탄소 투과도는 28.9 barrel 으로 나타났으며, 선택도($PCO_2$/$PN_2$)는 57.9로 나타났다. 같은 온도에서 PEG/PPG(5:5)로 조성을 변화시켰을 때 이산화탄소 투과도는 40.4 Barrer, 기체선택도($PCO_2$/$PN_2$)는 51.8를 나타냈다 이산화탄소의 투과도는 5:5 > 6:4 > 7:3 > 8:2 > 9:1의 경향을 나타내었다. $35^{\circ}C$로 승온을 하는 경우에 PEG/PPG (9:1)는 45.4 Baller, 선택도($PCO_2$/$PN_2$)는 48.2을 나타냈으며, PEG/PPG (5:5)의 이산화탄소 투과도는 78.9 Barrer을 나타내고 선택도($PCO_2$/$PN_2$)는 33.2로 나타났다. 각각의 온도에서 이산화탄소의 기체선택도($PCO_2$/$PN_2$)는 PPG의 함량이 증가하면서 감소하는 경향을 나타내었다.