A durable superhydrophobic porous polymer coated sponge for efficient separation of immiscible oil/water mixtures and oil-in-water emulsions.

Oil spills and organic solvents leakages have led to serious environmental problems, which calls for the emerging materials for the separation of oil/organic solvents from water effectively. Herein, a superhydrophobic/superoleophilic, SHMP-1@Sponge, with water contact angle (WCA) of 156° and oil contact angle of 0°, was fabricated by dip coating polymer SHMP-1 powder onto the skeleton of 3D melamine sponge. The SHMP-1@Sponge featured large specific surface area (556 m/g) as well as high chemical and mechanical durability. SHMP-1@Sponge can absorb up to 40-105 times of its own weight of light and heavy oils/organic solvents in seconds, and it can be recycled for 25 times by squeezing. Moreover, the separation efficiency of immiscible oil/water mixtures and oil-in-water emulsions by SHMP-1@Sponge are > 99.5％. SHMP-1@Sponge shows tremendous absorption capacity for chloroform-in-water emulsions (1460 mg/g) compared with nitrobenzene-in-water (1290 mg/g) and diesel-in-water emulsions (980 mg/g), which is the strongest superhydrophobic absorbent for surfactant-stabilized oil-in-water emulsions reported to date. The durable SHMP-1@Sponge fabricated by loading superhydrophobic polymer with large surface area onto 3D sponge makes it a promising material for oil/water separation in realistic aquatic environments.