Facile and Rapid Fabrication of (trifluoropropyl) Silsesquioxanes/Ethyl Cyanoacrylate-Based Hybrid Superhydrophobic Coatings for Oil–Water Separation and Metal Anticorrosion

In this paper, fluorosilsesquioxanes (F-SQs) were first synthesized by hydrolysis condensation of (3,3,3-trifluoropropyl) trimethoxysilane. Then, F-SQs were blended with ethyl cyanoacrylate (ECA) to prepare a hybrid matrix material that was coated on the surface of sponge or copper foil to rapidly form hydrophobic coatings by anionic polymerization of ECA, which were environmentally friendly, efficient, and low cost. The resulting low surface energy materials could be used for oil–water separation and metal corrosion protection. The structure composition and properties characterization of the surface of coated polyurethane (PU) sponges and copper foils were analyzed by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, water contact angle, and electrochemical tests. Coated PU sponges with excellent mechanical and chemical stability exhibit superhydrophobic properties and can efficiently separate oil and water mixtures with an efficiency over 99%. Compared with bare copper foil, the coated copper foil exhibited lower corrosion current (Icorr) and higher impedance modulus (|Z|0.01 Hz) after immersing in a 3.5 wt % NaCl solution for 24 h, offering excellent anticorrosion properties. Moreover, when the exposure time of the coating in salt solution was extended to 21 days, the |Z|0.01 Hz of the coating remained approximately 10 times higher than that of the Cu matrix, demonstrating exceptional long-term corrosion resistance. This simple and environmentally friendly route to fabricate hydrophobic materials makes it possible for large-scale oil–water separation and metal corrosion protection.