Main Article Content
In this work, an easy one-step and inexpensive technique of mechanical wet sanding was used to impart micro structures into the Teflon surface that promotes super repellent properties toward water and the two moderate low surface tension organic liquids. Sandpapers with a wide range of grit sizes 60-1000, with associated particle sizes of 256-10 µm, were used to obtain physical modification of the Teflon surface. The roughened Teflon surface with the sandpaper of 400 grit size showed super repellency toward water, glycerol, and ethylene glycol with CAs as high as 158°, 150°, and 142°, respectively, as well as the low sliding angle of less than 2°, 5°, and 15°, respectively. The obtained results and the effect of roughness were explained in terms of both fundamental wetting models of Wenzel and Cassie-Baxter. The effect of a decrease in liquid surface tension on the length scale of imparted geometries and consequent wetting state was also concluded. Finally, the work of adhesion for the tested liquids while on the roughened Teflon surfaces were also determined using both Young-Dupre relation and the liquid’s SAs.
Bhushan, B., and Nosonovsky, M. (2010). The Rose Petal Effect and the Modes of Superhydrophobicity Philosophical Transactions of the Royal Society London, Series A: Mathematical, Physical and Engineering Sciences, 368, 4713-28.
Bhushan, B.; Jung, Y. C.; Koch, K. Micro-, Nano- and Hierarchical Structures for Superhydrophobicity, Self-Cleaning and Low Adhesion. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 2009, 367, 1631-1672.
Cao, L.; Price, T. P., Weiss, M., Gao, D. (2008). Super Water- and Oil-Repellent Surfaces on Intrinsically Hydrophilic and Oleophilic Porous Silicon Films. Langmuir, 24, 1640-1643.
Cheng, Y. T., Rodak, D. E., Wong, C. A., Hayden, C. A. (2006). Effects of Micro- and Nano-Structures on the Self-Cleaning Behaviour of Lotus Leaves. Nanotechnology, 17, 1359-1362.
Chhatre, S. S., Choi, W., Tuteja, A., Park, K., Mabry, J. M., McKinley, G. H., Cohen, R. E. (2010). Scale Dependence of Omniphobic Mesh Surfaces. Langmuir, 26, 4027-4035.
Chien-Te, H., Fang-Lin, W., Wei-Yu C. (2009). Super Water- and Oil-Repellencies from Silica-Based Nanocoatings. Surf. Coat. Technol., 203, 3377-84.
Deng, X., Mammen, L., Butt, H., Vollmer, D. (2012). Candle Soot as a Template for a Transparent Robust Superamphiphobic Coating. Science, 335, 67-70.
Farshchian, B., Ok, J. T., Hurst, S. M., Park, S. (2010). Simple fabrication of hierarchical structures on a polymer surface; In NSTI Nanotechnology Conference and Expo, Anaheim, CA, (pp 665-668), USA.
Feng, L., Zhang, Y., Xi, J., Zhu, Y., Wang, N., Xia, F., Jiang, L. (2008). Petal Effect: A Superhydrophobic State with High Adhesive Force. Langmuir, 24, 4114-4119.
Gao, L., and McCarthy, T. J. (2006). A Perfectly Hydrophobic Surface (A/R = 180/180). J. Am. Chem. Soc., 128, 9052-9053.
Hsieh, C., Wu, F., Chen, W. (2009). Contact Angle Hysteresis and Work of Adhesion of Oil Droplets on Nanosphere Stacking Layers. J. Phys. Chem. C, 113, 13683-13688.
Lafuma, A., and Quere, D. (2003). Superhydrophobic States. Nature Materials, 2, 457-60.
Liam R. J. Scarratt, Ben S. Hoatson, Elliot S. Wood, Brian S. Hawkett, and Chiara N. (2016). Durable Superhydrophobic Surfaces via Spontaneous Wrinkling of Teflon AFACS Appl. Mater. Interfaces, 8, 6743–6750.
Nilsson, M. A., and Rothstein, J. P. (2012). Using Sharp Transitions in Contact Angle Hysteresis to Move, Deflect, and Sort Droplets on a Superhydrophobic Surface. Phys. Fluids, 24, 062001.
Nilsson, M. A., Daniello, R. J., Rothstein, J. P. (2010). A Novel and Inexpensive Technique for Creating Superhydrophobic Surfaces using Teflon and Sandpaper. J. Phys. D, 43, 045301.
Nosonovsky, M., and Bormashenko, E. (2009). In Lotus Effect: Superhydrophobicity and Self-Cleaning; Functional Properties of Bio-Inspired Surfaces Characterization and Technological Applications; World Scientific Publishing Co. Pte. Ltd, Singapore, pp 43-78.
Patankar, N. A. (2004) Transition between Superhydrophobic States on Rough Surfaces. Langmuir, 20, 7097-7102.
Patankar, N. A. (2009). Hydrophobicity of Surfaces with Cavities: Making Hydrophobic Substrates from Hydrophilic Materials? J. Adhes. Sci. Technol., 23, 413-33.
Song, D., Daniello, R.J. & Rothstein, J.P. (2014). Drag reduction using superhydrophobic sanded Teflon surfaces. J. P. Exp Fluids, 55, 1783.
Tuteja, A., Choi, W., Ma, M., Mabry, J. M., Mazzella, S. A., Rutledge, G. C., McKinley, G. H., Cohen, R. E. (2007). Designing Superoleophobic Surfaces. Science, 318, 1618-22.
Xiu, Y., Zhu, L., Hess, D. W., Wong, C. P. (2008). Relationship between Work of Adhesion and Contact Angle Hysteresis on Superhydrophobic Surfaces. J. Phys. Chem. C, 112, 11403-7.