DOI QR코드

DOI QR Code

The Behavioral Characteristics of a Droplet on the Line Patterned Surface Including Water Film

수막을 가지는 선형 젖음성 패턴 표면에서의 액적 거동 특성

  • Lee, Changwoo (Department of Mechanical Engineering, Pohang Univ. of Science and Technology) ;
  • Park, Jinyoung (Department of Mechanical Engineering, Pohang Univ. of Science and Technology) ;
  • Cho, Handong (Department of Mechanical Engineering, Pohang Univ. of Science and Technology) ;
  • Hwang, Woonbong (Department of Mechanical Engineering, Pohang Univ. of Science and Technology)
  • Received : 2013.10.16
  • Accepted : 2013.11.14
  • Published : 2013.12.01

Abstract

Herein the water film was introduced to the hydrophilic area on the line patterned surface to solve the contradiction caused by surface roughness (high different wettability has advantage to control the droplet but high roughness for that high wettability difference causes obstruction of droplet moving). Thus the droplet on the water film could not be hindered to line direction but restricted to orthogonal direction, effectively. In addition, droplet behaviors according to droplet volume and line thickness were studied. Droplet fell off the line with narrowing the interface between the droplet and the water film on the line. When the droplet fell off the line, the plate angle was designated as a critical plate angle and it used as an indicator of surface capability to control the droplet. As a result critical plate angle increases as droplet volume decreases and line thickness increases.

Keywords

References

  1. Wenzel, R. N., "Surface Roughness and Contact Angle," J. Phys. Colloid Chem., Vol. 53, pp. 1466-1467, 1949. https://doi.org/10.1021/j150474a015
  2. Cassie, A. B. D. and Baxter, S., "Wettability of Porous Surfaces," Trans. Faraday Soc., Vol. 40, pp. 546-551, 1944. https://doi.org/10.1039/tf9444000546
  3. Xu, X. and Qian, T., "Droplet Motion in One- Component Fluids on Solid Substrates with Wettability Gradients," Phys. Rev. E, Vol. 85, Paper No. 051601, 2012.
  4. Sun, T., Wang, G., Feng, L., Liu, B., Ma, Y., Jiang, L., and Zhu, D., "Reversible Switching between Superhydrophilicity and Superhydrophobicity," Angewandte Chemie International Edition, Vol. 43, No. 3, pp. 357-360, 2004. https://doi.org/10.1002/anie.200352565
  5. Suzuki, S., Nakajima, A., Tanaka, K., Sakai, M., Hashimoto, A., Yoshida, N., and et al., "Sliding Behavior Of Water Droplets On Line-Patterned Hydrophobic Surfaces," Applied Surface Science, Vol. 254, No. 6, pp. 1797-1805, 2008. https://doi.org/10.1016/j.apsusc.2007.07.171
  6. Garrod, R. P., Harris, L. G., Schofield, W. C., McGettrick, J., Ward, L. J., Teare, D. O., and Badyal, J. P., "Mimicking a Stenocara Beetle's Back for Microcondensation using Plasmachemical Patterned Superhydrophobic-Superhydrophilic Surfaces," Langmuir, Vol. 23, No. 2, pp. 689-693, 2007. https://doi.org/10.1021/la0610856
  7. Zhai, L., Berg, M. C., Cebeci, F. C., Kim, Y., Milwid, J. M., Rubner, M. F., and Cohen, R. E., "Patterned superhydrophobic surfaces: toward a synthetic mimic of the Namib Desert beetle," Nano Lett, Vol. 6, No. 6, pp. 1213-1217, 2006. https://doi.org/10.1021/nl060644q
  8. Abate, A. R., Thiele, J., Weinhart, M., and Weitz, D. A., "Patterning Microfluidic Device Wettability using Flow Confinement," Lab on a Chip, Vol. 10, No. 14, pp. 1774-1776, 2010. https://doi.org/10.1039/c004124f
  9. Xu, Q. F., Wang, J. N., Smith, I. H., and Sanderson, K. D., "Directing the Transportation of a Water Droplet on a Patterned Superhydrophobic Surface," Applied Physics Letters, Vol. 93, No. 23, Paper No. 233112, 2008.
  10. Geyer, F. L., Ueda, E., Liebel, U., Grau, N., and Levkin, P. A., "Superhydrophobic-Superhydrophilic Micropatterning: Towards Genome-on-a-Chip Cell Microarrays," Angewandte Chemie International Edition, Vol. 50, No. 36, pp. 8424-8427, 2011. https://doi.org/10.1002/anie.201102545
  11. Dorrer, C. and Ruhe, J., "Drops on Microstructured Surfaces Coated with Hydrophilic Polymers: Wenzel's Model and Beyond," Langmuir, Vol. 24, No. 5, pp. 1959-1964, 2008. https://doi.org/10.1021/la7029938
  12. Costacurta, S., Falcaro, P., Malfatti, L., Marongiu, D., Marmiroli, B., and et al., "Shaping Mesoporous Films using Dewetting on X-ray Pre-patterned Hydrophilic/ hydrophobic Layers and Pinning Effects at the Pattern Edge," Langmuir, Vol. 27, No. 7, pp. 3898-3905, 2011. https://doi.org/10.1021/la103863d
  13. Dupuis, A. and Yeomans, J. M., "Lattice Boltzmann Modelling of Droplets on Chemically Heterogeneous Surfaces," Future Generation Computer Systems, Vol. 20, No. 6, pp. 993-1001, 2004. https://doi.org/10.1016/j.future.2003.12.012
  14. Kusumaatmaja, H., Léopoldès, J., Dupuis, A., and Yeomans, J. M., "Drop dynamics on chemically patterned surfaces," EPL (Europhysics Letters), Vol. 73, No. 5, Paper No. 740, 2006.
  15. Kim, D., Lee, S., and Hwang, W., "Complete Wetting Characteristics of Micro/nano Dual-scale Surface by Plasma Etching to Give Nanohoneycomb Structure," Current Applied Physics, Vol. 12, No. 1, pp. 219-224, 2012. https://doi.org/10.1016/j.cap.2011.06.003
  16. Qian, B. and Shen, Z., "Fabrication of superhydrophobic surfaces by dislocation-selective chemical etching on aluminum, copper, and zinc substrates," Langmuir, Vol. 21, No. 20, pp. 9007-9009, 2005. https://doi.org/10.1021/la051308c
  17. Guo, Z., Zhou, F., Hao, J., and Liu, W., "Stable Biomimetic Super-hydrophobic Engineering Materials," Journal of the American Chemical Society, Vol. 127, No. 45, pp. 15670-15671, 2005. https://doi.org/10.1021/ja0547836
  18. Kim, Y., Lee, S., Cho, H., Park, B., Kim, D., and Hwang, W., "Robust Superhydrophilic/hydrophobic Surface Based on Self-aggregated Al2O3 Nanowires by Single-step Anodization and Self-assembly Method," ACS Appl Mater Interfaces, Vol. 4, No. 10, pp. 5074-5078, 2012. https://doi.org/10.1021/am301411z
  19. Cho, H., Kim, D., Lee, C., and Hwang, W., "A Simple Fabrication Method for Mechanically Robust Superhydrophobic Surface by Hierarchical Aluminum Hydroxide Structures," Current Applied Physics, Vol. 13, No. 4, pp. 762-767, 2013. https://doi.org/10.1016/j.cap.2012.11.021
  20. Long, C. J., Schumacher, J. F., and Brennan, A. B., "Potential for Tunable Static and Dynamic Contact Angle Anisotropy on Gradient Microscale Patterned Topographies," Langmuir, Vol. 25, No. 22, pp. 12982-12989, 2009. https://doi.org/10.1021/la901836w
  21. Monde, T., Fukube, H., Nemoto, F., Yoko, T., and Konakahara, T., "Preparation and Surface Properties of Silica-gel Coating Films Containing Branched- Polyfluoroalkylsilane," Journal of Non-Crystalline Solids, Vol. 246, No. 1-2, pp. 54-64, 1999. https://doi.org/10.1016/S0022-3093(99)00003-4