T. Nahum A. Panwar, H. Dodiuk, S. Kenig, C. Barry, J. Mead
Keywords: coating, superhydrophobic, durability, nanoparticles
Summary:Bottom up cost-effective and durable superhydrophobic coatings were formulated using hydrophobic silica nanoparticles and epoxy binder at different epoxy-to-silica nanoparticle ratios. The localization of the silica nanoparticles in the dissolved epoxy oligomers before curing and their effect on superhydrophobicity was studied using contact angle measurements (pendant drop). Surface free energy calculations were used to determine the oil repellency characteristics of the different formulated coatings. The optimized epoxy-to-silica nanoparticle ratio for hydrophobicity was investigated on different substrates using a primer layer to enhance durability and optimize superhydrophobicity. Durability was evaluated using the tape test (ASTM D3359), Taber test (ASTM D4060), and wind tunnel tests at different air velocities (80, 120, 140, and 160 mph). The results show improved durability, enabling the use of the coatings in commercial applications.