Fabrication and research of superhydrophobic paper for oil-water separation

In this work, we developed a facile and effective strategy to fabricate superhydrophobic paper based on micro-nano structure by the synergistic effect of nanoparticles and microporous made by breath figure method, which realized the in-situ self-assembly and integration of amphiphilic copolymer of Poly(St-co-HEMA), nano silica particles (SiO2) and polydimethylsiloxane (PDMS). Furthermore, the chemical composition of copolymer, surface morphology and wettability were well characterized by FTIR, 1HNMR, GPC, SEM and water contact angle measurements, respectively. The molar ratio of St to HEMA reached 15:1 and the concentrations of SiO2 achieved 15 mg/ml were identified to be the most effective system, which possessed outstanding water repellency with a CA of 165° and a SA of 2° and good self-cleaning ability. Besides, the as-prepared paper maintained the repellency to water under extreme conditions, including low-high temperature, strong acidic or alkaline solutions, ultrasonic treatment and cyclic sandpaper abrasion. Importantly, the superhydrophobicity paper could be utilized as effective functional nanomaterials for the separation of water-oil mixture with efficiency above 90% and repeatable for at least 20 times.