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 CA of 165 degrees and a SA of 2 degrees and good self-cleaning ability. Besides, the as-prepared paper maintained the repel-lency 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 lized as effective functional nanomaterials for the separation of water-oil mixture with efficiency above 90% repeatable for at least 20 times.

Automated summary

In this study, a facile and effective strategy was developed to fabricate superhydrophobic paper using micro nano structure and the breath figure method. Amphiphilic copolymer of Poly(St-co-HEMA), nano silica particles (SiO2), and polydimethylsiloxane (PDMS) were in-situ self-assembled and integrated. The most effective system had a St to HEMA molar ratio of 15:1 and a SiO2 concentration of 15 mg/ml, exhibiting outstanding water repellency with a contact angle of 165 degrees and a wetting angle of 2 degrees. The prepared paper maintained its water repellency under extreme conditions and could be used for efficient water-oil mixture separation with a repeatable efficiency above 90% for at least 20 times.