Highly efficient Oil/Water and brine Separations: Superhydrophobic hybrid isobornyl methacrylate coatings

• Facile and easy fabrication of a fluorine-free superhydrophobic coating with methacrylate chemistry and their efficient oil–water separation. A new type of monomer chemistry using iso -norbornyl groups, a bulky and hydrophobic monomers was used. • The coatings are robust and applicable to a wide variety of fluid and pollutant compositions including a non-pressure induced separation (gravity) of oil/water. • The coating was characterized by rheology, contact angle, FTIR, SEM-EDS, profilometry, and TGA, exhibiting a fast cure reaction, nanometrical texturing, and outstanding thermal stability. • The coated mesh screens exhibited > 99% efficiency on separating water from eight oils of wide commercial interest with hexane/saturated brines of NaCl, KCl or MgSO 4 , and have high recyclability. • Possible applications are in oil/water separators, de-icing technologies, and anti-microbial coatings. A rapid and facile method to obtain a fluorine-free, superhydrophobic/superoleophilic coating with superior thermal stability based on a cyclic methacrylate chemistry is reported. The chemical structure of the coating is based on the crosslinking reaction of isobornyl methacrylate, ethylene glycol dimethacrylate (crosslinker) and a 3-(trimethoxysilyl)propyl methacrylate (adhesive), using AIBN as initiator, toluene as solvent, and silica nanoparticles. Chemorheology results showed that the coating can be fully cured in 10 min at 100 °C, exhibiting a water contact angle (CA) of 165 ± 3°, and an oil CA of 0° for eight oils of wide commercial interest (gasoline, diesel, petroleum ether, kerosene, hexane, toluene, chloroform and dichloromethane). The superhydrophobic/superoleophilic exhibited nanostructures and multiscale roughness throughout the surface, and excellent adhesion properties on the mesh screen. Also, the coating exhibited outstanding oil/water separation efficiency (>99 %) for all eight types of oil/water mixtures studied, as well as for hexane/saturated brines of NaCl, KCl or MgSO 4 , besides having high recyclability. Isothermal and non-isothermal TGA revealed its high thermal stability, and the activation energy of thermal degradation according to the Kissinger and modified Ozawa models were 115.6 and 119.2 kJ/mol, respectively.