Fabrication and characterization of stable superhydrophobic fluorinated-polyacrylate/silica hybrid coating

• Published in: Applied surface science 2014-04, Vol.298, p.214-220
• Main Authors: Li, Kunquan, Zeng, Xingrong, Li, Hongqiang, Lai, Xuejun
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Emulsion polymerization; Exact sciences and technology; Fluorinated polyacrylate; Hybrid coating; Physics; Silica; Superhydrophobic
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2014.01.164

•The superhydrophobic PFA/SiO2 coating was successfully fabricated by spraying.•The synthesized PFA latex showed core–shell structure and good dispersion.•The PFA/SiO2 coating showed good resistance to acid and base, weather and heat.•The superhydrophobic coating could be fabricated on various substrates. The core–shell fluorinated-polyacrylate (PFA) emulsion was synthesized through emulsion polymerization method and the superhydrophobic PFA/SiO2 hybrid coating was successfully fabricated on the slide glass by spraying the mixture of PFA emulsion and hydrophobic SiO2 particles using ethanol as cosolvent. The PFA emulsion was characterized by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), water contact angle (WCA), transmission electron microscopy (TEM), and the effects of SiO2 content on the wetting behavior and surface morphology of PFA/SiO2 hybrid coating were investigated. To evaluate the stability of the hybrid coating, the acid and base resistance, weatherability and thermal stability were also studied. Results showed that the obtained PFA latex exhibited a core–shell structure with a particle size of 134.1nm and a narrow polydispersity of 0.03. With the increase of dodecafluoroheptyl methacrylate (DFMA) content in the latex shell from 0wt% to 31.8wt%, the WCA of the PFA film enlarged from 85° to 104°, indicating that the introduction of fluorinated monomer was effective in reducing the surface energy. By adding different amount of SiO2 particles, the surface morphology and wetting behavior of the PFA/SiO2 hybrid coatings could be controlled. When the mass ratio of SiO2 to PFA emulsion was 0.2, the surface roughness (Rq) increased to 173.6nm and the wetting behavior of the surface became superhydrophobic with a WCA of 153°, resulted from the corporation of low surface energy and the binary nano/microstructure on the surface. The as-prepared PFA/SiO2 hybrid coating showed good acid and base corrosion resistance, and it could keep superhydrophobicity after being heated at 250°C for 2h or exposed to ambient atmosphere for more than 3 months. Additionally, the superhydrophobic PFA/SiO2 hybrid coating could be applied to various substrates through spraying. This was a green and eco-friendly method in fabricating stable organic/inorganic hybrid superhydrophobic coating because none of toxic organic solvents were used during the whole process.