Mechanics of Composite Materials

, Volume 48, Issue 2, pp 229–234 | Cite as

Controllable wettability of paraffin-anodic aluminum oxide composite surface with a roughness tunable by thermal expansion

  • Ch. Lee
  • S. Lee
  • W. Hwang

The roughness of a composite surface, one of factors determining the contact angle (CA), is controlled by the difference in the thermal expansion of constituents of the composite. The CA on a composite surface can be calculated by using an equation derived from Cassie and Wenzel relations. A composite of paraffin and anodic aluminum oxide was fabricated to verify this equation. The CA on this surface changed from 63 to 113° as the temperature increased from 1 to 40°C.


composite Cassie relation anodization wetting 



This work was supported by the National Research Foundation of Korea (NRF) grant funded by Korea government (MEST) (No. 2010-0018457).


  1. 1.
    M. Nosonovsky and B. Bhushan, “Superhydrophobic surfaces and emerging applications: Non-adhesion, energy, green engineering,” Curr. Opin. Colloid. Interface Sci. 14, 270 (2009).CrossRefGoogle Scholar
  2. 2.
    R. N. Wenzel, “Surface roughness and contact angle,” J. Phys. Colloid. Chem. 53, 1466 (1949).CrossRefGoogle Scholar
  3. 3.
    A. Cassie and S. Baxter, “Wettability of porous surfaces,” Trans. Faraday Soc. 40, 546 (1944).CrossRefGoogle Scholar
  4. 4.
    H. Moon, S. K. Cho, R. L. Garrell, and C.-J. C. J. Kim, “Low voltage electrowetting-on-dielectric,” J. Appl. Phys., 92, 4080 (2002).CrossRefGoogle Scholar
  5. 5.
    S. A. Pollack MG and Fair RB., “Electrowetting-based actuation of droplets for integrated microfluidics,” Lab Chip., 2, 96 (2002).CrossRefGoogle Scholar
  6. 6.
    J. Lee, H. Moon, J. Fowler, T. Schoellhammer, and C.-J. Kim, “Electrowetting and electrowetting-on-dielectric for microscale liquid handling,” Sens. Actuators. A. Phys., 95, 259 (2002).CrossRefGoogle Scholar
  7. 7.
    H. Liu, L. Feng, J. Zhai, L. Jiang, and D. Zhu, “Reversible wettability of a chemical vapor deposition prepared ZnO film between superhydrophobicity and superhydrophilicity,” Langmuir, 20, 5659 (2004).CrossRefGoogle Scholar
  8. 8.
    T. Sun, G. Wang, L. Feng, B. Liu, Y. Ma, L. Jiang, and D. Zhu, “Reversible switching between superhydrophilicity and superhydrophobicity,” Angew. Chem. Int. Ed. Engl., 43, 357 (2004).CrossRefGoogle Scholar
  9. 9.
    J. S. Neil, et al., “The use of high aspect ratio photoresist (SU-8) for super-hydrophobic pattern prototyping,” J. Micromech. Microeng., 14, 1384 (2004).CrossRefGoogle Scholar
  10. 10.
    H. Masuda and K. Fukuda, “Ordered metal nanohole arrays made by a two-step replication of honeycomb structures of anodic alumina,” Science, 268, 1466 (1995).CrossRefGoogle Scholar
  11. 11.
    X. Wang and G.-R. Han, “Fabrication and characterization of anodic aluminum oxide template,” Microelectron. Eng., 66, 166. (2003)CrossRefGoogle Scholar
  12. 12.
    K. Wefers and C. Misra, Oxides and Hydroxides of Aluminum, Alcoa Laboratories (1987)Google Scholar
  13. 13.
    S. Numata, K. Fujisaki, and N. Kinjo, “Re-examination of the relationship between the packing coefficient and thermal expansion coefficient for aromatic polyimides,” Polymer, 28, 2282 (1987).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, Inc. 2012

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringPohang University of Science and Technology (POSTECH)PohangRepublic of Korea

Personalised recommendations