Membrane Journal (멤브레인)

The Membrane Society of Korea (한국막학회)
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Surface Hydrophilization of PVDF Membrane by Thermal Polymerization Lamination Process

열중합 Lamination 공정에 의한 PVDF 분리막의 표면 친수화

  • Lee, Se-Min (Department of Chemical Engineering, College of Engineering, Regional Innovation Center, Kyung Hee University) ;
  • Byun, Young-Jin (Department of Chemical Engineering, College of Engineering, Regional Innovation Center, Kyung Hee University) ;
  • Kim, Jin-Ho (R&D Technology Center, Econity Co., Ltd.) ;
  • Kim, Sung Soo (Department of Chemical Engineering, College of Engineering, Regional Innovation Center, Kyung Hee University)
  • 이세민 (경희대학교 공과대학 화학공학과 지역혁신센터) ;
  • 변영진 (경희대학교 공과대학 화학공학과 지역혁신센터) ;
  • 김진호 ((주) 에코니티 기술연구소) ;
  • 김성수 (경희대학교 공과대학 화학공학과 지역혁신센터)
  • Received : 2013.04.08
  • Accepted : 2013.06.19
  • Published : 2013.06.30
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Abstract

Hydrophilic monomers were polymerized for lamination on polyvinylidene fluoride (PVDF) membrane surface for hydrophilization of the membranes. Hydrophilization reduced the contact angle from $95^{\circ}$ to $55^{\circ}$ and enhanced the water flux by 10 times while it reduced the bovine serum albumin (BSA) adsorption amount to 1/4 level. Thermal polymerization process was optimized by examining several operation parameters. Dimethyl oxobuthyl acrylamide (DOAA) showed the best effect due to its better hydrophilicity than others. Increase of amount of monomer enhanced the performance until the optimum concentration of 30 wt%, beyond which excess amount of monomer resulted in homopolymerization to deteriorate the performance. Azobis (isobutyronitrile)(AIBN) initiator has greater activation temperature range than benzoyl peroxide (BPO) and it showed better hydrophilation performance. Two stage lamination process, application of initiator followed by monomer addition, was more effective than one stage process, addition of initiator and monomer at once, which still reduced the contact angle but also reduced the water flux by pore blocking phenomena.

친수성 단량체를 polyvinylidene fluoride (PVDF) 분리막 표면에 열중합으로 lamination하여 분리막을 친수화하였다. 친수화 처리 후 접촉각은 $95^{\circ}$에서 $55^{\circ}$까지 감소하였고 수투과량은 10배 이상 증가하였으며 bovine serum albumin (BSA) 흡착량은 1/4 수준으로 감소하였다. 열중합 공정에서 각 공정변수별 영향을 조사하였고 이를 최적화하였다. 단량체 중 dimethyl oxobuthyl acrylamide (DOAA)가 친수성이 높아 다른 단량체에 비하여 친수화 효과가 우수하였다. 단량체의 농도가 증가함에 따라 성능이 향상되었으나 30 wt% 이상의 경우 homopolymerization을 유발하여 성능을 저하시켰다. 개시제로 사용되었던 azobis (isobutyronitrile)(AIBN)의 활성 온도 범위가 benzoyl peroxide (BPO)의 활성온도 범위보다 넓기 때문에 높은 친수화 효율을 나타내었다. 개시제를 먼저 도포시켜주고 단량체를 나중에 첨가하는 2단계 lamination 방식이 일괄 공급하는 1단계 방식보다 친수화도는 크게 향상됐지만 pore blocking현상이 나타나면서 순수투과도는 매우 감소하였다.

Keywords

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