Superhydrophobic Surfaces Produced by Carbon Nanotube Modified Polystyrene Composite Coating

The present work investigates the enhancement of water repellency on engineering materials surfaces using nanoscale roughness inherent in multi-walled carbon nanotubes (MWCNTs) together with a hydrophobic polystyrene coating via a simple spraying-based technique. The coatings show both a high contact angle and a small sliding angle for water droplets. The different surfaces obtained exhibit contact angles from 125 degrees up to 153 degrees depending on the preparation conditions. The observations of the topology by scanning electron microscopy reveal that the nanostructure created by the MWCNTs and the microstructure induced by the deposition of polystyrene particles forming a two-level structure that conceptually mimics the lotus leaf surface are necessary to create stable superhydrophobic surfaces.