화학공학소재연구정보센터
Polymer, Vol.128, 108-118, 2017
Investigating the interrelationship of superhydrophobicity with surface morphology, topography and chemical composition in spray-coated polyurethane/silica nanocomposites
A one-step and efficient method, based on the spray-coating technique, was proposed to impart superhydrophobicity to an intrinsically hydrophilic polymer. The main aim is to establish correlations among surface morphology, topography and chemical composition of superhydrophobic surfaces. Introduction of non-solvent changed the ordered honeycomb-like morphology to an unordered strand-like morphology. Moreover, the concurrent addition of non-solvent and nanoparticles has led to a unique hierarchical morphology where silica nanoparticles decorated the PU strand-like structure resulting in a very high WCA value (160 degrees) and very low sliding angle (<2 degrees). The topography results were utterly in conformity with those attained by the morphological analysis, and both qualitative and quantitative descriptions were given. It was found that the uniformity of the roughened structure plays a crucial role in superhydrophobicity. Moreover, the aggregation of silica particles at the surface layer of the coatings was also influential which was further confirmed by X-ray photoelectron spectroscopy results. (C) 2017 Elsevier Ltd. All rights reserved.