Separation of oil-water via porous PMMA/SiO2 nanoparticles superhydrophobic surface

A porous superhydrophobic coating on filter paper is developed by employing solution-casting technique using polymethyl methacrylate-co-ethyl acrylate polymer (PMMA) and silica nanoparticles (SiO2). The wettability, surface topography and chemical composition of coating were examined. The coated filter paper shows a static water contact angle of 170 degrees +/- 2 degrees and sliding angle of 8 degrees +/- 1 degrees. Additionally, thermal stability by annealing at different temperature ranging 40-280 degrees C, UV stability, chemical stability by immersing in different solutions of pH range of 2-13, and mechanical durability by performing adhesive tape peeling, sand abrasion, and washing tests of coatings were evaluated. Petroleum ether - water mixture and emulsion were successfully separated via a simple filtering method by using coated filter paper with high separation efficiency. Furthermore, coating also exhibits the excellent self-cleaning property. This coating can apply for any size and shape of the filter papers and has tremendous industrial applications.