From fractal polymer dispersions to mechanically resistant waterborne superhydrophobic coatings

Abstract

The preparation of superhydrophobic coatings with good mechanical properties from waterborne dispersions is reported. This goal is achieved combining a high solids fractal dispersion of a hard and hydrophobic polymer and a film forming polymer dispersion (not necessarily hydrophobic) in a dual-casting strategy. The coatings are superhydrophobic (water contact angle > 150°) and oleophobic (olive oil contact angle = 120°). The mechanical strength was demonstrated by means of scrub resistance tests. The approach meets the requirements of the industrial coatings as it uses environmentally friendly waterborne polymer dispersions that can be produced in high tonnage and can be easily applied to large and irregular surfaces forming cohesive, non-porous and mechanically resistant coatings. In addition, no special preparation of the substrate is needed.