Influence of fluorine incorporation into waterborne acrylic coatings on resulting hydrophobic, thermal stability and drag- reduction properties

Fluorinated polyacrylate copolymers containing various amounts of 1H,1H,2H,2H-perfluorooctyl methacrylate (FA) were synthesized via a miniemulsion polymerization process. The characteristics of latex particles and films were investigated using transmission electron microscopy, dynamic light scattering, attenuated total reflectance Fourier transform infrared spectroscopy, 1H and 19F nuclear magnetic resonance spectroscopy, atomic force microscopy, energy dispersive spectroscopy, water contact angle measurements, and thermogravimetric analysis. The results showed that particle size increased almost linearly with FA content, and the surface hydrophobicity of the films increased with FA content up to 14.6 wt% and then plateaued. As the FA content increased, the surface roughness of the films initially increased and then decreased. The thermal stability of fluorinated polyacrylate was significantly enhanced when a high amount of FA was incorporated into the polymer chains. The fluorinated acrylic copolymer coating also exhibited a significant drag reduction effect, with the maximum drag reduction ratio reaching 12% at a water flow velocity of 0.8 m/s.