Membrane Journal (멤브레인)

The Membrane Society of Korea (한국막학회)
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Preparation and Characterization of Random Copolymer Electrolyte Membranes Containing PFCB (Perfluorocyclobutane) Group

PFCB (Perfluorocyclobutane) Group을 포함한 랜덤 공중합체 고분자 전해질 막 제조 및 특성연구

  • Kim Jeong-Hoon (Interface Materials and Process Team, New Chemistry Research Division, Korea Research Institute of Chemical Technology) ;
  • Kim Dong-Jin (Interface Materials and Process Team, New Chemistry Research Division, Korea Research Institute of Chemical Technology) ;
  • Chang Bong-Jun (Interface Materials and Process Team, New Chemistry Research Division, Korea Research Institute of Chemical Technology) ;
  • Lee Soo-Bok (Interface Materials and Process Team, New Chemistry Research Division, Korea Research Institute of Chemical Technology) ;
  • Joo Hyeok-Jong (Department of Polymer Science and Engineering, Chungnam National University)
  • 김정훈 (한국화학연구원 계면재료공정연구실) ;
  • 김동진 (한국화학연구원 계면재료공정연구실) ;
  • 장봉준 (한국화학연구원 계면재료공정연구실) ;
  • 이수복 (한국화학연구원 계면재료공정연구실) ;
  • 주혁종 (충남대학교 고분자공학과)
  • Published : 2006.09.01
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Abstract

This study is about the preparation and characterization of sulfonated random copolymer membranes containing perfluorocyclobutane (PFCB), fluorenyl, and sulfonyl units. The polymers were prepared through three synthetic steps, that is, the synthesis of a trofluorovinylether-terminated monomer, its thermal polymerization, and post-sulfonation using chlorosulfonic acid. A series of sulfonated random copolymers with different ion exchange capacity (IEC) were prepared by changing contents of fluorenyl uints in polymers with fixed molar ratio of chlorosulfonic acid during the post-sulfonation reaction. All the synthesized compounds were characterized by FT-lR, $^1H-NMR$, $^{19}F-NMR$, and Mass spectroscopy. As the content of sulfonated fluorenyl units increased, the IEC, water uptake, and ion conductivity of the sulfonated random copolymer membranes increased. The sulfonated random copolymer S-1 and S-2 showed higher values of ion conductivity than the Nafion-115 in a wide range of temperatures ($25{\sim}80^{\circ}C$).

본 연구는 불소관능기인 perfluorocyclobutane (PFCB), fluorenyl, sulfonyl계 방향족 화합물을 동시에 포함하는 술폰화된 랜덤 고분자 전해질 막의 제조 및 그 특성에 관한 것이다. 이러한 고분자 전해질 막은 세단계의 합성, 즉 trifluorovinyloxy그룹을 양말단에 포함하는 단량체의 합성, 중부가반응 형태의 열중합, 그리고 chlorosulfonic acid를 이용한 후술폰화를 통하여 얻어졌다. 후술폰화 반응은 고분자 내에 포함된 fluorenyl기의 함량에 따라 일정한 몰비의 술폰화제 비율로 고정하여 진행되었으며, 이에 따라 다양한 이온교환 능력(IEC)을 가지는 고분자를 쉽게 합성할 수 있었다. 제조된 단량체 및 고분자들의 구조와 순도는 각각 FT-IR과 NMR 그리고 질량분석기를 통하여 확인되었다. 술폰화된 fluorenyl기가 많아질수록 술폰화도와 이온교환 능력이 증가하는 것을 확인할 수 있었고 그에 따른 함수율도 역시 증가하는 거동을 보였다. 술폰화된 고분자들의 이온전도도를 측정한 결과 술폰화도가 증가할수록 이온 전도도가 증가하는 것을 관찰할 수 있었다, 이렇게 제조된 전해질막 중 S-1과 S-2의 경우 다양한 온도범위($25{\sim}80^{\circ}C$)에서 상용 전해질막인 Nafion-115를 능가하는 우수한 이온전도도를 나타냈다.

Keywords

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