• Title/Summary/Keyword: Vinyl ether

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Electro-optic Properties of Polymer Dispersed Liquid Crystal Displays: Effect of BDVE(Butanediol Vinyl Ether) & Temprature Stability (고분자 분산형 액정 표시 소자(PDLC)의 제작 및 측정: BDVE(Butanediol Vinyl Ether) 첨가에 따른 효과와 온도의존성 평가)

  • No, Young-Seok;Jeon, Chan-Wook
    • Korean Chemical Engineering Research
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    • v.46 no.5
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    • pp.938-944
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    • 2008
  • The electro-optic properties of polymer-dispersed liquid crystal cells containing BDVE(Butanediol vinyl ether) in PN393 base pre-polymer were examined. The higher the contents of BDVE, the smaller becomes the droplet size. However, the droplet size was saturated around $3{\mu}m$ even at 40 wt% of BDVE. Both of contrast ratio and response time of PDLC cell fabricated with a new formula were found to be superior to the reference cell with PN393 by the factor of 4.9 and 0.15, respectively. However, the new formula made the operating voltage go higher compared to the reference cell of PN393 formula. Except for contrast ratio, response time as well as operating voltage were found to be highly stabilized by adding BDVE in PN393 base pre-polymer over the temperature range of $0{\sim}60^{\circ}C$ studied.

Theoretical Study of Solvent Effect on Yield of Oxidative Addition Reaction (산화첨가반응의 수득률에 미치는 용매효과에 관한 이론적 연구)

  • Lee, Chul-Jae;Kim, Byung-So
    • Applied Chemistry for Engineering
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    • v.21 no.5
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    • pp.586-589
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    • 2010
  • In present work, oxidative addition reaction of 1,3-cycleohexandion (1,3-CHD) with ethyl vinyl ether (EVE) was attempted utilizing $Ag_2CO_3$/celite (SC) reagent. In order to optimize reaction conditions, we surveyed several solvents for the production of dihydrofuran with the (SC) system. The yield of the acetonitrile (AN), dimethyl sulfoxide (DMSO), benzene (BZ), and heptane (HT) are given 78, 40, 15, and 10%, respectively. Therefore, we studied the solvent effects on yields by using PM3 and ZINDO/1 parameter of semi-empirical method of HyperChem7.0 molecular modeling program.

A Novel Synthetic Route to Highly Cross-Linked Poly(alkylvinylether)s. Synthesis and Free Radical Polymerization of a Vinyl Ether Monomer Containing Electron Acceptors in Side Chain

  • 이주연;이현주;김무용
    • Bulletin of the Korean Chemical Society
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    • v.17 no.3
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    • pp.257-262
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    • 1996
  • p-(2-Vinyloxyethoxy)benzylidenemalononitrile 2 and methyl p-(2-vinyloxyethoxy)benzylidenecyanoacetate 3 was prepared by the condensation of p-(2-vinyloxyethoxy)benzaldehyde 1 with malononitrile or methyl cyanoacetate, respectively. Vinyl ether monomers 2 and 3 polymerized quantitatively with radical initiators in γ-butyrolactone solution at 65 ℃. The trisubstituted terminal double bond participated in the vinyl polymerization and radical polymerization of 2 and 3 led to swelling polymers 4 and 5 that were not soluble in common solvents due to cross-linking. Under the same polymerization conditions ethylvinyl ether polymerized well with model compounds of p-methoxybenzylidenemalononitrile 6 and methyl p-methoxybenzylidenecyanoacetate 7, respectively, to give 1:1 alternating copolymers 8 and 9 in high yields. Polymers 4 and 5 showed a thermal stability up to 300 ℃ without any characteristic Tg peaks in DSC thermograms. Alternating copolymers 8 and 9 were soluble in common solvents such as acetone and DMSO, and the inherent viscosities of the polymers were in the range of 0.36-0.74 dL/g. Films cast from acetone solution were cloudy and tough and Tg values obtained from DSC thermograms were in the range of 59-60 ℃.

Influences of Ionizing Radiation on Mechanical and Electrical Properties of Polymer Composites Based on Poly (vinyl ether of ethyleneglycol)

  • V.A. Kovtunets;A.I. Kupchishin;G.A. Mun;Z.S. Nurkeeva;G.T. Akhmetkalieva;V.V. Khutoryanskiy;Soh, Dea-wha
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05a
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    • pp.85-87
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    • 2004
  • Radiation technology is an effective way for regulating polymeric materials to physicochemical and mechanical properties. New polymeric hydrogels based on vinyl ethers have been synthesized by the ${\gamma}$-initiated polymerization method. In this paper, we have studied the effect of radiation on mechanical and electrochemical properties of new rubber-like polymeric composite materials based on poly (vinyl ether of ethyleneglycol: PVEEG).

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A Novel Synthetic Route to Highly Cross-Linked Poly(vinyl ethers): Ⅲ. Synthesis and Free Radical Polymerization of Aryloxyethyl Vinyl Ethers Having an Electron Acceptor in ortho- or meta-Position

  • 이주연;김무용;안광덕
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.318-323
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    • 1997
  • ο-(2-Vinyloxyethoxy)benzylidenemalononitrile (3a) and methyl ο-(2-vinyloxyethoxy)-benzylidenecyanoacetate (3b), m-(2-vinyloxyethoxy)benzylidenemalononitrile (4a), and methyl m-(2-vinyloxyethoxy)benzylidenecyanoacetate (4b) were prepared by the condensation of ο-(2-vinyloxyethoxy)benzaldehyde (1) and m-(2-vinyloxyethoxy)benzaldehyde (2) with malononitrile or methyl cyanoacetate, respectively. Bifunctional vinyl ether monomers 3a and 3b polymerized quantitatively with radical initiators in γ-butyrolactone solution at 65 ℃, while meta-isomers 4a and 4b gave lower yields of polymers under the same conditions. The polymers 5-6 obtained from the monomers 3-4 were insoluble in common solvents due to cross-linking. Under the same polymerization conditions ethyl vinyl ether polymerized well with model compounds ο-methoxybenzylidenemalononitrile 7a, methyl ο-methoxybenzylidenecyanoacetate 7b, m-methoxybenzylidenemalononitrile 8a, and methyl m-methoxybenzylidenecyanoacetate 8b, respectively, to give 1:1 alternating copolymers 9-10 in high yields. Cross-linked polymers 5-6 showed a thermal stability up to 300 ℃, and showed a double phase degradation pattern in their TGA thermograms. Polymers 5-6 showed broad endothermic bands around 75-110 ℃ without any characteristic Tg peaks in DSC thermograms. Alternating copolymers 9-10, except copolymer 9b were soluble in common organic solvents. The inherent viscosities of polymer 9-10 were in the range of 0.35-0.62 dL/g. Polymer films cast from acetone solution were cloudy and tough and Tg values obtained from DSC thermograms were in the range of 118-165 ℃.

Radical Polymerization of Vinyl Monomers to Poly(vinyl)s having nBu3Sn end Groups with Biological Activity

  • Park, Jaeyoung;Lee, Beomgi;Kim, Seongsim;Cheong, Hyeonsook;Gwak, Gyeongja;Lee, Ki Bok;Woo, Hee-Gweon
    • Journal of Integrative Natural Science
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    • v.6 no.2
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    • pp.71-75
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    • 2013
  • $Bu_3Sn$-endded poly(vinyl)s with biological activity were obtained by the radical polymerization of vinyl monomers using thianthrene cation radical/$^nBu_3H$. Thianthrene cation and stannyl radicals promoted the homopolymerization and copolymerization of styrene and ethyl vinyl ether having number average molecular weights of 2000-3100. Tributyltin hydride functions as a chain transfer agent. Such polymereization by cationic thianthrene and stannyl radicals could provide some clues for the biological reaction in living animals. Plausible polymerization mechanisms were suggested.

Response Characteristics of Ligand Free PVC Membranes (이온운반물을 사용치 않은 이온 선택성 막의 특성)

  • Kim, Young-Hak;Lee, Ji-Yeun;Jung, Moon-Mo;Kim, Eu-Jung;Hur, Moon-Hye;Ahn, Moon-Kyu
    • Analytical Science and Technology
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    • v.10 no.6
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    • pp.453-458
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    • 1997
  • Many polymeric poly(vinyl chloride) membrane electrodes have been developed for the determination of basic drugs. But relatively little has been roported concerning the behavior of ligand free PVC memebranes. In connection with the evaluation of various ionophores, we bave evaluated a near-Nernstian response and selectivity of these ligand-free PVC electrodes towards basic drugs such as alverine, chlorpromazine and promazine. The electrode membranes were constructed with only several plasticizer and poly (vinyl chloride) matrix. The plasticizer studied were dioctyl phenylphosphonate, 2-nitrophenyl octyl ether, isododecyl phenylphosphate and dioctyl maleate.

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