Modeling of Capillary Filling Length in Silwet L-77 Added Poly(Dimethylsiloxane) (PDMS) Microchannels

Silwet L-77 이 포함된 Polydimethylsiloxane(PDMS) 마이크로 채널의 유동 길이 모델링

  • Lee, Bom-Yee (School of Mechanical Engineering, Chonnam Nat'l Univ.) ;
  • Lee, Bong-Kee (School of Mechanical Engineering, Chonnam Nat'l Univ.)
  • 이봄이 (전남대학교 기계공학부) ;
  • 이봉기 (전남대학교 기계공학부)
  • Received : 2014.02.21
  • Accepted : 2014.06.11
  • Published : 2014.08.01


In the present study, simple models were proposed to predict the capillary-driven flow length in a surfactant-added poly(dimethylsiloxane) (PDMS) rectangular microchannel. Owing to the hydrophobic nature of PDMS, it is difficult to transport water in a conventional PDMS microchannel by means of the capillary force alone. To overcome this problem, microchannels with a hydrophilic surface were fabricated using surfactant-added PDMS. By measuring the contact angle change on the surfactant-added PDMS surface, the behavior was investigated to establish a simple model. In order to predict the filling length induced by the capillary force, the Washburn equation was modified in the present study. From the investigation, it was found that the initial rate-of-change of the contact angle affected the filling length. Simple models were developed for three representative cases, and these can be useful tools in designing microfluidic manufacturing techniques including MIcroMolding In Capillaries (MIMIC).


Capillary Force;Poly(dimethylsiloxane)(PDMS);Surfactant;Rectangular Microchannel


Supported by : 한국연구재단


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