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Synthesis of Poly(MMA-co-PEGMA) Electrolytes by Grafting-onto Method and Effect of Composition on Ionic Conductivities

Grafting-onto법에 의한 poly(MMA-co-PEGMA) 전해질의 합성과 이온전도도에 대한 조성의 영향

  • Lee, Ju-Hyung (Department of Engineering Chemistry, Chungbuk National University) ;
  • Ryu, Sang-Woog (Department of Engineering Chemistry, Chungbuk National University)
  • Received : 2013.10.16
  • Accepted : 2013.11.19
  • Published : 2013.11.30

Abstract

Copolymer consisted of MMA and tBMA was synthesized by radical polymerization and poly(MMA-co-MA) was prepared by selective hydrolysis of tert-butyl group. The obtained polymer was coupled with epoxy functionalized PEO of various molecular weight to synthesize poly(MMA-co-PEGMA) with different side chain length. The AC-impedance measurement shows $1.88{\times}10^{-6}Scm^{-1}$ of room temperature ionic conductivity from 48mol% of MMA while $5.11{\times}10^{-8}Scm^{-1}$ was observed in 82mol% sample. In addition, there was an effect of PEGMA molecular weight on ionic conductivity possibly due to the steric hindrance in grafting-onto coupling reaction. Finally, the polymer electrolytes shows electrochemical stability up to 6V at room temperature.

본 실험에서는 MMA와 tBMA의 공중합체를 합성하고, tert-butyl 그룹의 가수분해를 선택적으로 유도하여 poly(MMA-co-MA)를 제조하였다. 또한 말단에 에폭시기를 함유한 다양한 분자량의 PEO와 MA와의 grafting-onto 커플링 반응을 통해 같은 주사슬을 가지지만 부사슬의 길이가 다른 poly(MMA-co-PEGMA)를 합성하여 조성이 이온전도도에 미치는 영향을 평가하였다. AC-impedance로 측정한 상온 이온전도도는 MMA의 몰분율이 82%에서 $5.11{\times}10^{-8}Scm^{-1}$의 값이 얻어진 반면, 48%에서는 $1.88{\times}10^{-6}Scm^{-1}$로서 많은 PEGMA에서 높게 관찰되었다. 또한 에폭시기를 함유한 PEO의 분자량에 따라 이온전도도의 차이가 발생하는데, grafting-onto 법의 입체적 장애가 원인으로 고려되었다. 한편, 합성된 poly(MMA-co-PEGMA) 고분자 전해질은 상온에서 6V까지 우수한 전기화학적 안정성을 보여주었다.

Keywords

References

  1. J. MacCallum, and C. Vincent, 'Polymer Electrolyte Reviews-1' 69, Elsevier Applied Science, New York (1987).
  2. G.-A. Nazri, and G. Pistoia, 'Lithium Batteries Science and Technology' 574, Kluwer Academic Publishers, New York (2004).
  3. M. Yosho, R. Brodd, and A. Kozawa, 'Lithium-ion Batteries' 413, Springer, New York (2009).
  4. J. Saunier, F. Alloin, J. Sanchez, and G. Caillon, 'Thin and flexible lithium-ion batteries: investigation of polymer electrolytes' J. Power Sources, 119-121, 454 (2003). https://doi.org/10.1016/S0378-7753(03)00197-6
  5. F. Dias, L. Plomp, and J. Veldhuis, 'Trends in polymer electrolytes for secondary lithium batteries' J. Power Sources, 88, 169 (2000). https://doi.org/10.1016/S0378-7753(99)00529-7
  6. D. Kim, J. Song, and J. Park, 'Synthesis, characterization and electrical properties of the novel polymer electrolytes based on polyesters containing ethylene oxide moiety' Electrochimica Acta, 40, 1697 (1995). https://doi.org/10.1016/0013-4686(95)00078-S
  7. J. Acosta, and E. Morales, 'Structural, morphological and electrical characterization of polymer electrolytes based on PEO-PPO blends' Solid State Ionics, 85, 85 (1996). https://doi.org/10.1016/0167-2738(96)00045-8
  8. A. Nishimoto, M. Watanabe, Y. Ikeda, and S. Kohjiya, 'High ionic conductivity of new polymer electrolytes based on high molecular weight polyether comb polymers' Electrochimica Acta, 43, 1177 (1998). https://doi.org/10.1016/S0013-4686(97)10017-2
  9. Y. Ikeda, Y. Wada, Y. Matoba, S. Murakami, and S. Kohjiya, 'Characterization of comb-shaped high molecular weight poly(oxyethylene) with tri(oxyethylene) side chains for a polymer solid electrolyte' Electrochimica Acta, 45, 1167 (2000). https://doi.org/10.1016/S0013-4686(99)00377-1
  10. P. Jannasch, 'Ion conducting electrolytes based on aggregating comblike poly(propylene oxide)' Polymer, 42, 8629 (2001). https://doi.org/10.1016/S0032-3861(01)00373-1
  11. E. Gomez, A. Panday, E. Feng, V. Chen, G. Stone, A. Minor, C. Kisielowski, K. Downing, O. Borodin, G. Smith, and N. Balsara, 'Effect of ion distribution on conductivity of block copolymer electrolytes' Nano Letters, 9, 1212(2009). https://doi.org/10.1021/nl900091n
  12. W. Young, and T. Epps, III, 'Ionic conductivities of block copolymer electrolytes with various conducting pathways: sample preparation and processing considerations' Macromolecules, 45, 4689(2012). https://doi.org/10.1021/ma300362f
  13. D. Kim, Y. Kim, J. Kim, and S. Moon, 'Electrical properties of the plasticized polymer electrolytes based on arcylonitrile-methyl methacrylate copolymer' Solid State Ionics, 106, 329 (1998). https://doi.org/10.1016/S0167-2738(97)00498-0
  14. Z. Chen, L. Zhang, R. West, and K. Amine, 'Gel electrolyte for lithium-ion batteries' Electrochimica Acta, 53, 3262 (2008). https://doi.org/10.1016/j.electacta.2007.10.058
  15. T. Niitani, M. Shimada K. Kawamura, and K. Kanamura, 'Characteristics of new-type solid polymer electrolyte controlling nano-structure' J. Power Sources, 146, 386 (2005). https://doi.org/10.1016/j.jpowsour.2005.03.102
  16. K. Kim, and S. Ryu, 'Synthesis and electrochemical properties of solid polymer electrolytes using $BF_3LiMA$ as monomer' J. Kor. Electrochem. Soc., 14, 208 (2011). https://doi.org/10.5229/JKES.2011.14.4.208
  17. K. Kim, and S. Ryu, 'Synthesis of self-doped poly(PEGMA-co-$BF_3LiMA$) electrolytes and effect of PEGMA molecular weight on ionic conductivities' J. Kor. Electrochem. Soc., 15, 230 (2012). https://doi.org/10.5229/JKES.2012.15.4.230
  18. E. Ruckenstein, and H. Zhang, 'Grafting by in situ coupling of epoxy group of a living copolymer with an anionic living polymer' J. Polym. Sci.: Part A: Polym. Chem., 37, 105 (1999). https://doi.org/10.1002/(SICI)1099-0518(19990101)37:1<105::AID-POLA12>3.0.CO;2-T
  19. D. Rahlwes, J. Roovers, and S. Bywater, 'Synthesis and characterization of poly(styrene-g-isoprene) copolymers' Macromolecules, 10, 604 (1977). https://doi.org/10.1021/ma60057a021
  20. M. Takaki, R. Asami, and M. Mizuno, 'Anionic grafting reaction of living polystyrene with poly(p-vinylstyrene oxide) and its styrene copolymer' Macromolecules, 10, 845 (1977). https://doi.org/10.1021/ma60058a024
  21. S. Ryu, and A. Hirao, 'Anionic synthesis of well-defined poly(m-halomethylstyrene)s and branched polymers via graft-onto methodology' Macromolecules, 33, 4765 (2000). https://doi.org/10.1021/ma991793g