Characterization of PVdF/Laponite Reinforced Composite Membranes for PEMFC Surpport

PEMFC 지지체용 PVdF/Laponite 강화 복합막의 특성평가

  • Oh, Seul-Gi (School of Materials Science and Engineering, Engineering Research Institute, i-Cube Center, Gyeongsang National University) ;
  • Hwang, Hae-Young (School of Materials Science and Engineering, Engineering Research Institute, i-Cube Center, Gyeongsang National University) ;
  • Kim, Hyoung-Juhn (Fuel Cell Research Center, Korea Institute of Science and Technology) ;
  • Nam, Sang-Yong (School of Materials Science and Engineering, Engineering Research Institute, i-Cube Center, Gyeongsang National University)
  • 오슬기 (경상대학교 나노신소재공학과, 아이큐브 사업단) ;
  • 황해영 (경상대학교 나노신소재공학과, 아이큐브 사업단) ;
  • 김형준 (한국과학기술연구원 연료전지연구센터) ;
  • 남상용 (경상대학교 나노신소재공학과, 아이큐브 사업단)
  • Received : 2010.06.14
  • Accepted : 2010.06.22
  • Published : 2010.06.30

Abstract

In this study, high porous PVdF flat sheet membranes were prepared to obtain reinforced membrane support for polymer electrolyte membrane fuel cell. Nano-size laponite was randomly dispersed in the membranes to improve mechanical property which lowered by the high porosity. The morphology and porosity of prepared PVdF/Laponite composite membranes were examined using the SEM analysis and the weight method and all membranes showed over 60% porosity. The membrane thermal stability depending on the laponite contents in the composite membranes was evaluated by membrane heat shrinkage at $105^{\circ}C$ and $135^{\circ}C$. MD and TD heat shrinkage of the PVdF composite membrane containing 5 wt% laponite was 2~3% and 2~3.5% at $135^{\circ}C$, respectively. The mechanical strength was enhanced after incorporating laponite particles and 30% increase in the modulus compared to pure PVdF membrane was obtained.

본 연구에서는 연료전지용 강화 복합막 지지체 제조를 위해 높은 다공성을 가지는 PVdF 평막을 제조하였다. 높은 다공도로 인한 낮은 기계적 강도를 보완하기 위한 방법으로 나노 사이즈의 laponite를 막 내에 분산시켰다. 제조된 PVdF/Laponite 복합막의 모폴로지 및 다공도는 SEM 분석 및 무게 중량법을 사용하여 평가하였고, 60% 이상의 다공도를 보였다. 첨가된 laponite 함량에 따른 막의 열적 안정성은 $105^{\circ}C$, $135^{\circ}C$에서의 수축률을 이용하여 평가하였으며, laponite 함량이 5%일 때 $135^{\circ}C$에서 MD와 TD방향으로의 열 수축률 2~3%와 2~3.5%를 나타내었다. Laponite 첨가 후 막의 기계적 강도가 향상되었으며, 순수 PVdF 막에 비해 약 30%의 모듈러스 증가를 나타내었다.

Keywords

Acknowledgement

Grant : PEMFC용 강화 복합막 Matrix 개발

Supported by : 대학산업기술지원단(UNITEF), 한국과학기술연구원(KIST)

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