• Title/Summary/Keyword: Chemical energy

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Synthesis and Properties of Ionic Liquids:Imidazolium Tetrafluoroborates with Unsaturated Side Chains

  • Min, Gwan-Hong;Yim, Tae-eun;Lee, Hyun-Yeong;Huh, Dal-Ho;Lee, Eun-joo;Mun, Jun-young;Oh, Seung M.;Kim, Young-Gyu
    • Bulletin of the Korean Chemical Society
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    • v.27 no.6
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    • pp.847-852
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    • 2006
  • Imidazolium tetrafluoroborate ionic liquids having unsaturated aliphatic side chains were synthesized and characterized. Most of them are liquid at room temperature and all of them are stable up to $300{^{\circ}C}$. Some imidazolium tetrafluoroborates with an allylic side chain showed much wider voltage windows on the platinum electrode, better conductivities, and lower viscosities compared with the corresponding ionic liquids containing the saturated side chains.

Synthesis and Physicochemical Properties of Ionic Liquids: 1-Alkenyl-2,3-dimethylimidazolium Tetrafluoroborates

  • Min, Gwan-Hong;Yim, Tae-Eun;Lee, Hyun-Yeong;Kim, Hyo-Jin;Mun, Jun-Young;Kim, Sang-Mi;Oh, Seung-M.;Kim, Young-Gyu
    • Bulletin of the Korean Chemical Society
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    • v.28 no.9
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    • pp.1562-1566
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    • 2007
  • 1-Alkenyl-2,3-dimethylimidazolium tetrafluoroborate ionic liquids having an olefinic substituent were synthesized and characterized. Among them, [AMMIm]BF4 with an allyl group showed lower viscosity, higher ionic conductivity, and a wider electrochemical window compared with its analogue having a saturated alkyl substituent. An EDLC with [AMMIm]BF4 showed better performance than that with [PMMIm]BF4, too.

A New Model and Equation Derived From Surface Tension and Cohesive Energy Density of Coagulation Bath Solvents for Effective Precipitation Polymerization of Acrylonitrile

  • Zhou, You;Xue, Liwei;Yi, Kai;Zhang, Li;Ryu, Seung Kon;Jin, Ri Guang
    • Carbon letters
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    • v.13 no.3
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    • pp.182-186
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    • 2012
  • A new model and resultant equation for the coagulation of acrylonitrile monomers in precipitation polymerization are suggested in consideration of the surface tension (${\gamma}$) and cohesive energy density ($E_{CED}$). The equation was proven to be quite favorable by considering figure fittings from known surface tensions and cohesive energy densities of certain organic solvents. The relationship between scale value of surface tension (${\gamma}$/M) and cohesive energy density of monomers can be obtained by changing the coagulation bath component for effective precipitation polymerization of acrylonitrile in wet spinning.

Electrical Repulsive Energy between Two Cylindrical Particles with Finite Length: Configuration Dependence

  • Choi, Ju-Young;Dong, Hyun-Bae;Haam, Seung-Joo;Lee, Sang-Yup
    • Bulletin of the Korean Chemical Society
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    • v.29 no.6
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    • pp.1131-1136
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    • 2008
  • The electrical repulsive energy between two model cylinders was calculated by solving nonlinear Poission- Boltzmann (P-B) equation under Derjaguin approximation. Effects of the surface potential, Debye screening length, and configuration of cylinders on the repulsive interaction energy were examined. Due to the anisotropy of the shape of cylinder, the interaction repulsive energy showed dependence to the configuration of particles; cylinders aligned in end-to-end configuration showed largest repulsive energy and crossed particles had lowest interaction energy. The configuration effect is originated from the curvature effect of the interacting surfaces. The curved surfaces showed less repulsive energy than flat surfaces at the same interacting surface area. The configuration dependency of interaction energy agreed with the previous analytical solution obtained under the linearized P-B equation. The approach and results present in this report would be applicable in predicting colloidal behavior of cylindrical particles.