Fabrication of Super-Hydrophobic Microchannels via Strain-Recovery Deformations of Polystyrene and Oxygen Reactive Ion Etch

Anirban Chakraborty; Mingming Xiang; Cheng Luo

doi:10.3390/ma6083610

Fabrication of Super-Hydrophobic Microchannels via Strain-Recovery Deformations of Polystyrene and Oxygen Reactive Ion Etch

Materials (Basel). 2013 Aug 19;6(8):3610-3623. doi: 10.3390/ma6083610.

Authors

Anirban Chakraborty¹, Mingming Xiang², Cheng Luo³

Affiliations

¹ Department of Mechanical and Aerospace Engineering, University of Texas, Arlington, TX 76019, USA. anirban.chakraborty@gmail.com.
² Department of Mechanical and Aerospace Engineering, University of Texas, Arlington, TX 76019, USA. mingming.xiang@mavs.uta.edu.
³ Department of Mechanical and Aerospace Engineering, University of Texas, Arlington, TX 76019, USA. chengluo@uta.edu.

Abstract

In this article, we report a simple approach to generate micropillars (whose top portions are covered by sub-micron wrinkles) on the inner surfaces of polystyrene (PS) microchannels, as well as on the top surface of the PS substrate, based on strain-recovery deformations of the PS and oxygen reactive ion etch (ORIE). Using this approach, two types of micropillar-covered microchannels are fabricated. Their widths range from 118 μm to 132 μm, depths vary from 40 μm to 44 μm, and the inclined angles of their sidewalls are from 53° to 64°. The micropillars enable these microchannels to have super-hydrophobic properties. The contact angles observed on the channel-structured surfaces are above 162°, and the tilt angles to make water drops roll off from these channel-structured substrates can be as small as 1°.

Keywords: hybrid micro/nanostructures; shape-memory polymer; super-hydrophobic microchannels.