Evaluation of hydrophobic attraction between polystyrene layer and silanated silica surface by atomic force microscopy

Abstract

In this study, hydrophobic surfaces were prepared by depositing polystyrene (PS) on a glass substrate using three different methods to measure the interaction forces against a hydrophobized particle by atomic force microscopy. We found that smooth surfaces prepared by spin coating and living radical polymerization generated hydrophobic attraction, whereas uneven surfaces obtained by free radical polymerization produced only steric repulsion, even though they had sufficient hydrophobicity. Based on these results, the origin of the hydrophobic attraction was suggested. The interaction forces between hydrophobic surfaces prepared by depositing polystyrene on a glass substrate using three different methods and a hydrophobized particle were measured by atomic force microscopy. Surfaces prepared by spin coating and living radical polymerization generated hydrophobic attraction, whereas surfaces obtained by free radical polymerization produced no hydrophobic attraction, despite sufficient hydrophobicity. Based on these results, the origin of the hydrophobic attraction was suggested.