Membrane Journal (멤브레인)

The Membrane Society of Korea (한국막학회)
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Effect of Heat Capacity of Coagulant on Morphology of PVDF-Silica Mixture Through TIPS Process for the Application of Porous Membrane

다공성 분리막으로 응용을 위한 PVDF-실리카 혼합물의 응고액 열용량 변화에 따른 모폴로지 변화

  • Lee, Jeong Woo (Department of materials Engineering and Convergence Technology, Engineering Research Institute, Gyeongsang National University) ;
  • Nam, Sang Yong (Department of materials Engineering and Convergence Technology, Engineering Research Institute, Gyeongsang National University)
  • 이정우 (경상대학교 나노신소재융합공학과, 공학연구원) ;
  • 남상용 (경상대학교 나노신소재융합공학과, 공학연구원)
  • Received : 2017.10.26
  • Accepted : 2017.10.30
  • Published : 2017.10.31
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Abstract

In this study, we prepared PVDF membranes via TIPS for water treatment applications. PVDF was used for its excellent chemical and mechanical properties. The effect of coagulation bath composition, temperature, and heat capacity on the overall membrane morphology was studied and observed using SEM. A mixture of DOP and DBP was used as the diluent, and silica was used as an additive. It was observed that as the heat capacity of the coagulation bath increased, the crystallization rate of PVDF decreased yielding larger pores. Also, as the heat capacity of the coagulation bath decreased, the crystallization rate of PVDF increased yielding smaller pores.

본 연구는 열유도 상분리법(thermally induced phase separation, TIPS)을 사용하여, 수처리 분리막에 적용하기 위해, 응고조의 열용량의 변화를 위해 서로 다른 두 용액의 함량을 조절하였다. 또한, 온도의 변화를 통해 분리막의 구조 변화에 대하여 관찰하였다. 분리막을 제조하기 위한 소재로는 수처리 분리막에 주로 이용되는 기계적 물성과 내화학성이 우수한 poly (vinylidene fluoride)(PVDF)를 사용하였고, 첨가제로 실리카를 이용하였다. 희석제는 PVDF와 호환성이 좋은 dioctyl phthalate (DOP), dibutyl phthalate (DBP)를 사용하였다. 응고액의 함량 변화에 따른 열용량 변화에 따라 제조된 분리막의 구조를 관찰하기 위해 SEM 이미지를 촬영하였다. 열용량이 증가할수록 PVDF의 결정화 속도가 느려져 큰 기공을 나타내며 열용량이 작을수록 결정화 속도가 증가하여 작은 기공이 생기는 것을 확인하였다.

Keywords

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