Crosslinked Composite Polymer Electrolyte Membranes Based On Diblock Copolymer and Phosphotungstic Acid

디블록 공중합체와 인텅스텐산을 이용한 가교형 복합 고분자 전해질막

  • Kim, Jong-Hak (Department of Chemical Engineering, Yonsei University) ;
  • Koh, Joo-Hwan (Department of Chemical Engineering, Yonsei University) ;
  • Park, Jung-Tae (Department of Chemical Engineering, Yonsei University) ;
  • Seo, Jin-Ah (Department of Chemical Engineering, Yonsei University) ;
  • Kim, Jong-Hwa (Department of Chemical Engineering, Yonsei University) ;
  • Jho, Young-Choong (Department of Chemical Engineering, Yonsei University)
  • Published : 2008.06.30

Abstract

Proton conductive hybrid nanocomposite polymer electrolyte membranes comprising polystyrene-5-poly (hydroxyethyl methacrylate) (PS-b-PHEMA), sulfosuccinic acid (SA) and phosphotungstic acid (PWA) were prepared by varying PWA concentrations. The PHEMA block was thermally crosslinked by SA via the esterification reaction between -OH of PHEMA and -COOH of SA. Upon the incorporation of PWA into the diblock copolymer, the symmetric stretching bands of the $SO_3^-$ group at $1187cm^{-1}$ shifted to a lower wavenumber at $1158cm^{-1}$, demonstrating that the PWA particles strongly interact with the sulfonic acid groups of SA. When the concentration of PWA was increased to 30wt%, the proton conductivity of the composite membrane at room temperature increased from 0.045 to 0.062 S/cm, presumably due to the intrinsic conductivity of the PWA particles and the enhanced acidity of the sulfonic acid in the membranes. The membrane containing 30wt% of PWA exhibited a proton conductivity of 0.126 S/cm at $100^{\circ}C$. Thermal stability of the composite membranes was also enhanced by introducing PWA nanoparticles.

폴리스티렌-블록-폴리히드록에틸 메타크릴레이트(PS-b-PHEMA), 술포석시닉산(SA), 인텅스텐산(PWA)으로 구성된 수소 이온 전도성 나노복합 고분자 전해질막을 제조하였다. 폴리히드록에틸 메타크릴레이트(PHEMA) 블록의 히드록실그룹(-OH)와 술포석시닉산(SA)의 -COOH 그룹과의 에스테르 반응에 의하여 전해질막을 가교시켰다. 폴리헤테로산(PWA)을 도입했을 때, $SO_3^-$ 그룹의 신축 밴드가 $1187cm^{-1}$에서 $1158cm^{-1}$로 낮아졌으며, 이는 PWA 입자가 전해질막의 술폰산 그룹과 상호작용함을 나타낸다. PWA 함량이 30wt%가 되었을 때, 상온 전도도는 0.045에서 0.062S/cm로 증가되었으며, 이는 PWA 입자의 고유 전도도 특성과 전해질막의 술폰산기의 산도가 증가했기 때문이다. 또한 30wt%를 함유한 복합 전해질막은 $100^{\circ}C$에서는 최대 0.126 S/cm의 수소 이온 전도도를 나타내었다 PWA가 첨가됨에 따라 복합 전해질막의 열적특성 또한 증가하였다.

Keywords

References

  1. S. W. Kuo, C. H. Wu, and F. C. Chang, 'Thermal Properties, Interactions, Morphologies, and Conductivity Behavior in Blends of Poly(vinylpyridine)s and Zinc Perchlorate', Macromolecules, 37, 192 (2004) https://doi.org/10.1021/ma035655+
  2. D. K. Lee, K. J. Lee, Y. W. Kim, B. R. Min, and J. H. Kim, 'Nanostructure, Interactions and Conductivities of Polymer Electrolytes Comprising Silver Salt and Microphase-separated Graft Copolymer', J. Polym. Sci. B. Polym. Phys., 45, 1018 (2007) https://doi.org/10.1002/polb.21086
  3. J. H. Kim, M. S. Kang, Y. J. Kim, J. Won, N. G. Park, and Y. S. Kang, 'Dye-Sensitized Nanocrystalline Solar Cells Based on Composite Polymer Electrolytes Containing Fumed Silica Nanoparticles', Chem. Commun., 14, 1662 (2004)
  4. J. H. Kim, B. R. Min, J. Won, S. H. Joo, H. S. Kim, Y. S. Kang, 'Role of Polymer Matrix in Polymer/Silver Complexes for Structure, Interactions, and Facilitated Olefin Transport', Macromolecules, 36, 6183 (2003) https://doi.org/10.1021/ma034314t
  5. D. J. Kim, B.-J. Chang, C. K. Shin, J.-H. Kim, S.-B. Lee, and H.-J. Joo, 'Preparation and Characterization of Fluorenyl Polymer Electrolyte Membranes Containing PFCB Groups', Membrane Journal, 16, 16 (2006)
  6. J.-H. Choi, P.-H. Kang, Y.-M. Lim, J.-Y. Sohn, J.-H. Shin, C.-H. Jung, J.-P. Jeun, and Y.-C. Nho, 'Preparation and Characterization of Poly(styrenesulfonic acid)-grafted Fluoropolymer Membrane for Direct Methanol Fuel Cell,' Korean Membr. J., 9, 52 (2007)
  7. C. H. Park, C. H. Lee, Y. S. Chung, and Y. M. Lee, 'Preparation and Characterization of Crosslinked Block and Random Sulfonated Polyimide Membranes for Fuel Cell', Membrane Journal, 16, 241 (2006)
  8. L. Depre, M. Ingram, C. Poinsignon, and M. Popall, 'Proton conducting sulfon/sulfonamide functionalized materials based on inorganicorganic matrices', Electrochim. Acta, 45, 1377 (2000) https://doi.org/10.1016/S0013-4686(99)00346-1
  9. S. D. Mikhailenko, K. Wang, S. Kaliaguine, P. Xing, G. P. Robertson, and M. D. Guiver, 'Proton conducting membranes based on cross-linked sulfonated poly(ether ether ketone) (SPEEK)', J. Membr. Sci., 233, 93 (2004) https://doi.org/10.1016/j.memsci.2004.01.004
  10. S.-L. Chen, J. B. Benziger, A. B. Bocarsly, and T. Zhang, 'Photo-Cross-Linking of Sulfonated Styrene-Ethylene-Butylene Copolymer Membranes for Fuel Cells', Ind. Eng. Chem. Res., 44, 7701 (2005) https://doi.org/10.1021/ie050015b
  11. Z. Li, J. Ding, G. P. Robertson, and M. D. Guiver, 'A Novel Bisphenol Monomer with Grafting Capability and the Resulting Poly(arylene ether sulfone)s, Macromolecules, 39, 6990 (2006) https://doi.org/10.1021/ma061054h
  12. J. R. Varcoe, R. C. T. Slade, E. L. H. Yee, S. D. Poynton, D. J. Driscoll, and D. C. Apperley, 'Poly (ethylene-co-tetrafluoroethylene)-Derived Radiation-Grafted Anion-Exchange Membrane with Properties Specifically Tailored for Application in Metal-Cation-Free Alkaline Polymer Electrolyte Fuel Cells.', Chem. Mater., 19, 2686 (2007) https://doi.org/10.1021/cm062407u
  13. J. H. Choi, C. K. Yeom, J. M. Lee, and D. S. Suh, 'Nanofiltration of Electrolytes with Charged Composite Membranes', Membrane Journal, 13, 29 (2003)
  14. C. Manea and M. Mulder, 'Characterization of polymer blends of polyethersulfone/sulfonated polysulfone and polyethersulfone/sulfonated polyetheretherketone for direct methanol fuel cell applications', J. Membr. Sci., 206, 443 (2002) https://doi.org/10.1016/S0376-7388(01)00787-6
  15. C. Heitner-Wirguin, 'Recent advances in perfluorinated ionomer membranes: structure, properties and applications', J. Membr. Sci., 120, 1 (1996) https://doi.org/10.1016/0376-7388(96)00155-X
  16. D. K. Lee, Y. W. Kim, J. K. Choi, B. R. Min, and J. H. Kim, 'Preparation and Characterization of Proton Conducting Crosslinked Diblock Copolymer Membranes', J. Appl. Polym. Sci., 107, 819 (2008) https://doi.org/10.1002/app.27122
  17. Y. W. Kim, J. K. Choi, J. T. Park, and J. H. Kim, 'Proton Conducting Poly(vinylidene fluoride-cochlorotrifluoroethylene) Graft Copolymer Electrolyte Membranes', J. Membr. Sci., 313, 315 (2008) https://doi.org/10.1016/j.memsci.2008.01.015
  18. Z. Wang, H. Ni, C. Zhao, X. Li, T. Fu, and H. Na, 'Investigation of sulfonated poly(ether ether ketone sulfone)/heteropolyacid composite membranes for high temperature fuel cell applications', J. Polym. Sci. B: Polym. Phys., 44, 1967 (2006) https://doi.org/10.1002/polb.20841
  19. Y. S. Kim, F. Wang, M. Hickner, T. A. Zawodzinski, and J. E. McGrath, 'Fabrication and characterization of heteropolyacid ($H_3PW_{12}O_{40}$/directly polymerized sulfonated poly(arylene ether sulfone) copolymer composite membranes for higher temperature fuel cell applications', J. Membr. Sci., 212, 263 (2003) https://doi.org/10.1016/S0376-7388(02)00507-0
  20. T. Z. Fu, C. J. Zhao, S. L. Zhong, G. Zhang, K. Shao, H. Q. Zhang, J. Wang, and H. Na, 'SPEEK/epoxy resin composite membranes in situ polymerization for direct methanol fell cell usages', J. Power Sources, 165, 708 (2007) https://doi.org/10.1016/j.jpowsour.2006.12.023
  21. J. K. Choi, D. K. Lee, Y. W. Kim, B. R. Min, and J. H. Kim, 'Composite Polymer Electrolyte Membranes Comprising Triblock Copolymer and Heteropolyacid for Fuel Cell Applications', J. Polym. Sci. B. Polym. Phys., 46, 691 (2008) https://doi.org/10.1002/polb.21390
  22. J. T. Park, K. J. Lee, M. S. Kang, Y. S. Kang, and J. H. Kim, 'Nanocomposite Polymer Electrolytes Containing Silica Nanoparticles: Comparison between Poly(ethylene glycol) and Poly(ethyleneoxide) dimethyl ether', J. Appl. Polym. Sci., 106, 4083 (2007) https://doi.org/10.1002/app.26951
  23. K. D. Kreuer, 'Proton Conductivity: Materials and Applications', Chem. Mater., 8, 610 (1996) https://doi.org/10.1021/cm950192a