• 제목/요약/키워드: Maleic Anhydride

검색결과 257건 처리시간 0.023초

Synthesis and Physicochemical Properties of Polynucleotide Analogues Containing Pyrimidine Bases

  • 한만중;김기호;우경수;장지영;박영동
    • Bulletin of the Korean Chemical Society
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    • 제21권3호
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    • pp.321-327
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    • 2000
  • Polynucleotide analogues containing pyrimidine (uracil and thynime) bases, $poly[(1'{\beta}-uracil-1-yl-2'.5'-dideoxy-D-glycero-pent-4'-enofuranose)-alt-(maleic$ acid)] (12) and $poly[(1'-{\beta}-thymin-1-yl-2'5'-dideoxy-D-glycero-pent-4'-enofuranose)-alt-(maleic$, acid)] (15), were synthesized by the altermating copolymerization of relevant nucleosied derivatives and maleic anhydride, and the subsequent hydrolysis. The polymers had quite similar structures to the natural polymes and were soluble in water, They showed high hypochromicities up to 49% and excimer fluorescence due to the base stacking, and polyelectrolyte behavior. Since the polymers had compact structrures, depyrimidinations, the release of pyrimidine bases from the polymer backbone, occurred in aqueous solutions with higher rates compared with those of the natural polymers.

액화목재복합체(LWPC)의 제조 및 물성 (Preparation and Properties of Liquefied-Wood Polymer Composite)

  • 김철현;김강재;엄태진
    • Current Research on Agriculture and Life Sciences
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    • 제27권
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    • pp.29-33
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    • 2009
  • Liquefied-wood polymer composite was prepared and mechanical properties was evaluated to develop potential utility of liquefied wood. The liquefied wood was made from waste wood and chemical modified with acetic anhydride and maleic anhydride (MA), phtalic anhydride (PA). The composite sheet was prepared from modified liquefied-wood and polymer(PE). The mechanical, chemical and microscopical properties composite sheet were investigated. The results were summarized as follows, 1. The tensile strength was increased and breaking elongation of composite sheet was decreased with the time of acetylation and the dosage of MA. 2. The Young's modulus of composite sheet was gradually decreased with the dosage of PA. 3. The peak intensity of 1737cm-1 in FT-IR spectra of chemical modified liquefied woods was increased. 4. The dispersity of liquefied woods with PE was improved with chemical modification.

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Poly(dimethylsiloxane) 변성 EPDM/HDPE 복합체의 제조와 PTC 특성 (Preparation and PTC Characteristics of Poly(dimethylsiloxane) Modified EPDM/HDPE Composite)

  • 강두환;김성수
    • 폴리머
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    • 제32권4호
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    • pp.353-358
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    • 2008
  • EPDM에 maleic anhydride를 그래프트시켜 말레화 EPDM(MEPDM)을 제조하고 여기에 양 말단에 hydroxyl기를 갖는 $\alpha$,$\omega$-poly(dimethylsiloxane)(PDMS)을 반응시켜 MEPDM-g-PDMS 공중합체를 제조하였다. MEPDM-g-PDMS와 HDFE 및 4-ethoxybenzoic acid로 표면처리된 MWCNT를 internal mixer에 가하고 $180^{\circ}C$에서 컴파운딩하여 MEPDM-g-PDMS/HDPE/CNT 복합체를 제조하였다. 복합체에서 CNT의 모폴로지를 전자현미경으로 측정한 결과 표면처리된 CNT를 사용한 경우가 분산이 균일하게 이루어졌으며 입자의 응집현상도 감소되는 것으로 나타났다. 온도변화에 따른 전기저항은 용융온도부근에서 전기저항이 급격히 증가하였으며 EtO-CNT의 함량을 15%로 하여 제조한 복합체의 경우가 PTC intensity가 2.3으로 가장 우수한 PTC 특성을 나타내었다.

몇 개의 전이금속 이온과 고분자와 고분자 Complex의 합성과 특성연구 (Synthesis and Characterization of Polymer and Polymer Complex with Some Transition Metal Ions)

  • Badr, S.K.;Mohamed, T.Y.
    • 대한화학회지
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    • 제54권1호
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    • pp.43-48
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    • 2010
  • p-페닐렌 디아민과 maleic anhydride, 아세틸 아세톤과 커플된 O-아미노 페놀의 아조화합물으로 부터 폴리이미드가 만들어졌다. 합성된 폴리이미드(PA)는 DMF용매 속에 다른 몰비율로 녹아있는 $Co^{+2},\;Cr^{+2},\;Ni^{+2},\;Cu^{+2},\;Zn^{+2},\;Cd^{+2}$ and $Fe^{+3}$ 를 포함하는 전이금속이온들의 금속염들과 함께 환류되었다. 이 complex들은 원소분석과 열분석, IR, $^1H$ NMR으로 구조분석, 특성 연구되었다.

잠재적 항암작용이 있는 6-Allylthio-3-aminopyridazine 유도체의 합성 (Synthesis of Potential Anticancer 6-Allylthio-3-aminopyridazine Derivatives)

  • 박은희;박명숙
    • 대한화학회지
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    • 제51권3호
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    • pp.244-250
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    • 2007
  • 항암작용이 기대되는 일련의 새로운 6-allylthio-3-aminopyridazine 유도체를 allylthiolation, amination을 이용하여 합성하였다. 피리다진 핵은 hydrazine monohydrate와 maleic anhydride의 축합반응으로 제조하였다. 3,6- Dichloropyridazine은 3,6-dihydroxypyridazine을 POCl3에 가하여 합성하였다. 6-Allythio-3-chloropyridazine은 3,6- dichloropyridazine에 allylmercaptan과 sodium hydroxide을 이용하여 얻었다. Morpholine, piperazine, pyrazole, imidazole, pyrrolidine, piperidine, perhydroazepine 및 perhydroazocine와 같은 질소 친핵체를 갖는 hetero환을 피리 다진 환의 3번 위치에 도입시켜 6-allylthio-3-aminopyridazine 합성하였다. 이 과정은 아민 친핵체의 친핵성 치환반응 으로 n-buthanol에서 NH4Cl를 가하고 24~48시간 동안 환류시켜 진행하였다.

POLYPROPYLENE/CLAY NANOCOMPOSITES FOR AUTOMOTIVE APPLICATIONS

  • HONG C. H.;LEE Y. B.;JHO J. Y.;NAM B. U.;HWANG T. W.
    • International Journal of Automotive Technology
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    • 제6권6호
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    • pp.665-670
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    • 2005
  • Nanocomposites of polypropylene with organically modified clays were compounded on a twin-screw extruder by two-step melt compounding of three components, i.e., polypropylene, maleic anhydride grafted polypropylene (PP-g-MA), and organically modified clay. The effect of PP-g-MA compatibilizers, including PH-200, Epolene-43, Polybond-3002, Polybond-3200, with a wide range of maleic anhydride (MA) content and molecular weight was examined. Morphologies of nanocomposites and their mechanical properties such as stiffness, strength, and impact resistance were investigated. X-ray diffraction patterns showed that the dispersion morphology of clay particles seemed to be determined in the first compounding step and the further dispersion of clays didn't occur in the second compounding step. As the ratio of PP-g-MA to clay increased, the clay particles were dispersed more uniformly in the matrix resin. As the dispersibility of clays was enhanced, the reinforcement effect of the clays increased, however impact resistance decreased.

표면개질 및 분산제어된 다중벽 탄소나노튜브를 이용한 염료감응태양전지 대전극의 제조 (Fabrication of counter electrodes for dye-sensitized solar cells by using surface modified and dispersion controlled multi-walled carbon nanotubes)

  • 최희정;이기원;박남규;김경곤;홍성철
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.445-447
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    • 2008
  • 본 연구에서는 다중벽 탄소나노튜브용 표면개질제를 리빙라디칼중합법을 통하여 제조하고, 이를 이용하여 표면개질되고 분산제어된 다중벽탄소나노튜브를 제조하고 염료감응형 태양전지의 대전극 재료로 사용하였다. 우선 리빙라디칼중합법 중 nitroxide mediated polymerization (NMP) 기술을 이용하여 poly(maleic anhydride-co-p-acetoxystyrene)-block-poly(p-acetoxystyrene)를 합성하고, 공중합체중의 maleic anhydride기에 이미드화 반응을 통하여 pyrene기를 도입하였다. 공중합체 중의 p-acetoxystyrene 반복단위들은 가수분해 반응을 통하여 p-hydroxystyrene 반복단위로 변환하였으며, 제조된 공중합체의 구조와 열 특성 등을 GPC, GC, $^1H$-NMR, TGA을 통하여 분석하였다. 제조된 공중합체를 이용하여 다중벽 탄소나노튜브의 표면을 polymer wrapping법으로 처리하였고, 표면개질된 탄소나노튜브의 분산성을 다양한 용매에서 비교분석하였다. 표면이 개질되고 페이스트 내에의 분산성이 향상된 다중벽탄소나노튜브를 염료감응태양전지의 대전극 제조에 응용하였으며, 표면처리 및 분산제어 여부에 따른 제작 특성 및 동작특성 등을 평가하였다.

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이온성 망상구조막에 기반한 전기 활성 고분자 구동기 (Electro-Active Polymer Actuator by Employing Ionic Networking Membrane of Poly (styrene-alt-maleic anhydride)-Incorporated Poly (vinylidene fluoride))

  • 여군;김상균;이선우;오일권
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.714-717
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    • 2007
  • In this study, a novel actuator was developed by employing the newly-synthesized ionic networking membrane (INM) of poly (styrene-alt-maleic anhydride) (PSMAn)-incorporated poly (vinylidene fluoride) (PVDF). Based on the same original membrane, various samples of INM actuator were prepared through different reduction times with the electroless-plating technique. The as-prepared INM actuators were tested in terms of surface resistance, platinum morphology, resonance frequency, tip displacement, current and blocked force, and their performance was compared to that of the widely-used traditional Nafion actuator. Scanning electron microscope (SEM) and transmission electron microscopy (TEM) revealed that much smaller and more uniform platinum particles were formed on the surfaces of the INM actuators as well as within their polymer matrix. Although excellent harmonic response was observed for the newly-developed INM actuators, this was found to be sensitive to the applied reduction times during the fabrication. The mechanical displacement of the INM actuator fabricated after optimum reduction times was much larger than that of its Nafion counterpart of comparable thickness under the stimulus of constant and alternating current voltage.

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