Emulsion-templated, polymerization-free, ultralight sponges for oil spills reclamation

We report the fabrication of monolithic, macroporous, hydrophobic polymer sponges from a water-in-oil (w/o) high internal phase emulsion (HIPE) without using polymerization process. They were formed from sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SSEBS) and tetra-functional poly(amidoamine) (PAMAM) dendrimers via ionic interaction within a W/O HIPE. The sponges obtained possessed typical emulsion-templated interconnected macroporous structures, with void size ranging from 1 to 20 μm and a density of 0.08–0.1 g mL–1. The sponges were hydrophobic, with a water contact angle of around 128.1°, enabling highly selective absorption of oil from oil-water mixture with an absorption capacity from 15.4 to 25.8 g g–1 for organic solvents and oils. The sponges were recyclable and their absorption capacity was preserved at around 85% after being reused for 30 times. The high selectivity, absorption capacity and reusability enabled these sponges to be an excellent candidate in the reclamation of oils from wastewater and oil leakage.