One-step preparation of durable pH-responsive polyurethane foam for oil/water separation

The smart responsive materials have become one of the hottest areas of research in oil/water separation field and there are various studies on preparation technologies. However, most of the materials reported were prepared by coating or coupling to attach functional polymer to substrates, which generally had unstable physical and chemical properties and were difficult to be applied in harsh environments. In this work, we fabricated a smart and durable oil/water separation material by one-step foaming method to graft pH-responsive copolymer onto a polyurethane foam (PUF) substrate. The foam exhibited reversible wettability under different pH environments, had excellent oil adsorption capacity (24.78–64.27g/g) and high oil/water separation efficiency (above 98%). Besides, the foam also showed stable performance and excellent recyclability in a series of durability experiments, including mechanical abrasion, light radiation and chemical immersion. The foam with simple preparation process and excellent stability will have promising application prospects in the field of oil/water separation.