A rapid and efficient strategy for creating super-hydrophobic coatings on various material substrates

Abstract

A new phase separation methodology has been initially proposed for creating white or colorful super-hydrophobic coatings on the surfaces of various material substrates simply by using a common polymer, i.e., polycarbonate (PC), and its solvent and non-solvents suitably selected. The cleaned substrates were first dipped into the PC polymer solution and then further treated with the PC non-solvent, forming a super-hydrophobic coating at ambient room temperature within ∼21 min. It was found that PC coatings could present various surface morphologies and tunable hydrophobic characteristics if treated with different polymer non-solvents, as characterized in SEM images. The developed protocol can allow the super-hydrophobic coatings to be fabricated without any further surface modifications, showing water contact angles (CAs) of up to 160° and rolling angles of less than 5°. They might well retain super-hydrophobicity over the whole pH range and have long-term mechanic stability. Colorful super-hydrophobic surfaces could also be produced by doping different oily paints or dyes into the PC matrixes. Such a fabrication methodology may be extended to a wide variety of polymers, which may open up new avenues for creating super-hydrophobic coatings on various material substrates especially those with intricate shapes (i.e., channels) in industrial and biological processes.