Controlled Fabrication of Superhydrophobic Hierarchical Structures Using Epf/carbon Based Composites

We have prepared and characterized a series of nonfluoro polymer composites with functional carbon additives such as graphite, candle soot and camphor soot which when mixed with EPF (Expanded Polystyrene Foam) matrices increase surface hydrophobicity. Water contact angles of >150° was observed on spin-cast composite film surfaces containing 3% camphor soot particles, compared to 89° in the absence of any additive. These films reveal surface roughness which is more than for plain spin-cast films and demonstrate enhanced self cleaning property. FESEM was used to quantify the surface morphology to identify the characteristics of the additives as a function of composition and functionality. The forest of flakes and nano protrusion were available in these films, which facilitates to enhance the water contact angle. The surfaces reveal that the additive undergoes with the matrix when the composite films are allowed to dry in at ambient temperature and forms hierarchical structure.