• 제목/요약/키워드: LB films

검색결과 391건 처리시간 0.023초

크라운 기능기를 포함한 덴드리머 및 Staff-type 고분자 단분자막의 분자거동 및 전기ㆍ화학적 특성 (Molecular Behavior and Electro-Chemical Properties of Dendrimer and Staff-type Polymer Monolayers in Crown Function Group)

  • 장정수
    • 대한전기학회논문지:시스템및제어부문D
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    • 제52권5호
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    • pp.213-213
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    • 2003
  • We investigated the monolayer behavior at the air-water interface with metal solution, the surface morphologies and the electrical properties such as conductivity, The calculated conductivity values of pure water subphase and its complexes with L $i^{+}$ ions are 5.6$\times$10$^{-l6}$ and 1.9$\times$10$^{-14}$ [S/cm], respectively. And the calculated barrier height D values of pure water subphase and its complexes with Li. ions are 0.70 and 0.66 [eV], respectively. We also attempted to fabricate a crown dendrimer Langmuir-Blodgett (LB) films containing functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In conclusion, it is demonstrated that the metal ion around dendrimer and polymer included crown function group can contribute to make formation of network structure among crown function group and result in change of electrical properties.s.s.

크라운 기능기를 포함한 덴드리머 및 Staff-type 고분자 단분자막의 분자거동 및 전기ㆍ화학적 특성 (Molecular Behavior and Electro-Chemical Properties of Dendrimer and Staff-type Polymer Monolayers in Crown Function Group)

  • 장정수
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제52권5호
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    • pp.213-218
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    • 2003
  • We investigated the monolayer behavior at the air-water interface with metal solution, the surface morphologies and the electrical properties such as conductivity, The calculated conductivity values of pure water subphase and its complexes with L $i^{+}$ ions are 5.6$\times$10$^{-l6}$ and 1.9$\times$10$^{-14}$ [S/cm], respectively. And the calculated barrier height D values of pure water subphase and its complexes with Li. ions are 0.70 and 0.66 [eV], respectively. We also attempted to fabricate a crown dendrimer Langmuir-Blodgett (LB) films containing functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In conclusion, it is demonstrated that the metal ion around dendrimer and polymer included crown function group can contribute to make formation of network structure among crown function group and result in change of electrical properties.s.s.

생체박막의 상전이와 분자배열특성 (Phase Transition of Biology Thin Film and Molecule Arrangement Properties)

  • 김병근;전동규;김영근;구할본;이우선;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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    • pp.103-106
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    • 2003
  • It is well known that the state of existence of molecules on the surface of water changes during compression of the molecules. Electric methods, such as measurement of the surface potential or displacement current are also useful for investigating dynamic changes of molecular state on the water surface during compression. In this paper, We studied on the Bio thin film by Langmuir-Biodgett(LB) method. The Experiment method used displacement current, $\pi-A$ isotherm and BAM (Brewster Angle Microscopy). using the BAM, we can to the molecular orientation of monolayer on the water surface and directly see the morphology of the films on water subphase as well as that of the films.

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Langmuir-Blodgett Films of Perfluoroalkyl Monomaleate Copolymers on Porous Substrate

  • Hyein Jeong;Burm-Jong Lee;Young-Soo Kwon
    • Bulletin of the Korean Chemical Society
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    • 제15권8호
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    • pp.650-654
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    • 1994
  • Stable polyion-complexed polymeric monolayers were prepared by spreading perfluoroalkyl monomaleate copolymers, $C_2F_8MA-VE_2$ and $C_2F_8MA-VE_3$, on a aqueous poly(allylamine) subphase. The monolayer properties have been studied by the surface pressure-area (${\pi}$-A) isotherms. The $C_2F_8MA-VE_3$ containing longer oligoethyleneglycol pendant showed more expanded monolayer phase than the $C_2F_8MA-VE_2$. The polyion-complexed monolayers were transferable on various substrates, and the resulting Langmuir-Blodgett (LB) films were characterized by FT-IR spectroscopy and scanning electron microscopy (SEM). Two-dimensional crosslinking to form a polymer network was achieved by amide formation through heat treatment under vacuum with concurrent removal of perfluoroalkyl tails. SEM observation of this film on a porous membrane filter showed that the four layer film was sufficiently stable to cover the filter pore size of 0.1 ${\mu}$m. The $C_2F_8MA-VE_3$ revealed better covering capability than the $C_2F_8MA-VE_2$. Immersion of this film in water or in benzene did not cause any change in its appearance and in Fl-IR spectra.

Spectral Change and Surface Images of the Azobenzene Functionalized Dendrimer in LB Monolayers

  • Shin, Hoon-Kyu;Kwon, Young-Soo
    • KIEE International Transactions on Electrophysics and Applications
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    • 제11C권4호
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    • pp.146-149
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    • 2001
  • The functionalized dendrimer containing 48 azobenzene was synthesized. Many isolated featureless domains were explicitly observed even at the air/water interface. Also, these monolayers were representatively observed, showing the change of surface pressure with irradiation time and wavelength. In AFM images, larger domains irregularly shaped structures on the top, while smaller ones were free from such defects. In the optical absorption spectra of the monolayer films by UV irradiation and heat treatment, only the photoiosmerization of the G4-48 Azo monolayers was observed, revealing a decrease of absorbance peaks without any change of the spectral shape. This suggests that the functional group and the symmetric chain affect optical behavior and morphological change.

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Ultra-thin Film Assembly of a Novel Biomaterial Containing Protein and Functionalized Polymer for Sensor Application

  • 임정옥;손병기;허증수
    • 센서학회지
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    • 제4권4호
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    • pp.81-87
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    • 1995
  • A novel biomaterial capable of incorporating biotinylated biomolecule has been synthesized. Our strategy is to biotinylate one-dimensional electroactive polymers and use a bridging streptavidin protein on Langmuir-Blodgett (LB) organized films. These copolymers are derivatized with long alkyl chains and biotin moieties to bind, respectively, to the hydrophobic surface and the biotinylated species, through the biotin and streptavidin complexation. We utilize the polymer assembly approach to attach a signal transducing biomolecule biotinylated phycoerythrin (B-PE) into this novel biomaterial by binding the unoccupied biotin binding sites on the bound streptavidin (4 sites total). The pressure-area isotherm of the protein injected monolayer showed area expansion. A characteristic fluorescent emission peak at 576nm was detected from the monolayer transferred onto a solid substrate. These observations demonstrated the promise of the organized thin polymer assemblies for their application to the sensor system.

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아조벤젠이 기능화된 덴드리머 유기단분자막의 광학적 성질과 특성 (Characteristics and Optical Properties of the Azobenzene Functionlized Dendrimer in Organic Thin Monolayers)

  • 손정호;윤회찬;김정명;김병상;신훈규;장정수;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.182-185
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    • 2001
  • The functionlized dendrimer containing 48 azobenzene was synthesized. Many isolated featureless domains were explicitly observed even at the air-water interface. Also, these monolayers were representatively observed, showing the change of surface pressure with irradiation time and wavelength. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In the optical absorption spectra of the LB films by UV irradiation and heat treatment, only photoisomerization of the G4-48Az monolayers was observed, a decrease of absorbance peak without change of the spectral shape. This suggests that optical behavior and morphological change are affected by the functional group and the symmetric chain.

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Structure Formation in Multilayered Films Prepared by the Layer-by-Layer Deposition using PAA and HM-PEO

  • Seo, Jin-Hwa;Lutkenhaus Jodie L..;Kim, Jun-Oh;Hammond Paula T.;Char Kook-Heon
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.295-295
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    • 2006
  • In present study, poly(acrylic acid) (PAA) and hydrophobically modified poly(ethylene oxide) (HM-PEO) multilayers based on the hydrogen bonding between the component polymer pair have been prepared by the LbL deposition method. Dip assembled HM-PEO/PAA multilayers yield unique film morphologies in comparison with PEO/PAA multilayers due to the micellar formation of HM-PEO owing to the hydrophobic attraction between alkyl chains end-capped with the PEO chains. Individual HM-PEO micelles were connected through the bridging PEO chains to form temporary networks on multilayer surface and induced peculiar surface morphology on HM-PEO/PAA multilayers above the critical number of bilayers.

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Polyamic Acid 알킬아민 염의 랭뮤어-블로젯막 제작에 관한 연구 (A Study on the Preparation of Polyamic Acid Alkylamine Salt Langmuir-Biodgett Films)

  • 정순욱;임현성
    • 한국응용과학기술학회지
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    • 제17권4호
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    • pp.226-232
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    • 2000
  • Polyimide is a well-known organic dielectric material, which has not only high chemical and thermal stability but also good electrical insulating and mechanical properties. In this research, we have synthesized a polyamic acid(PAA), which is a precursor of the polyimide. To obtain the optimum conditions of polyamic acid alkylamine salt(PAAS) Langmuir-Blodgett(LB) film deposition, the ${\pi}-A$ isotherms were examined by varying subphase temperature, barrier moving speed and spreading amount of solution. Film formation was verified by measuring transfer ratio, absorption of UV/vis spectra and scanning electron microscope(SEM) images.