Centrifugally spun superhydrophobic fibrous membranes with core-sheath structure assisted by hyper branched polymer and via click chemistry for high efficiency oil–water separation

Superhydrophobic fibrous membranes have been widely investigated to treat oily wastewater originated from oil spills and industrial organic pollutants. However, the applications of these membranes are usually limited by complex preparation process, high modification cost, and poor durability. In this research, we developed a cost-saving approach to construct the fiber with core-sheath structure by using centrifugal spinning, which was based on the viscosity difference of Polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), hyperbranched unsaturated polyester (HBPU). Subsequently, the hydrophobic long chain was attended on fiber surface through the mercaptan click reaction induced by ultraviolet light, which were assisted by the plenty of double bonds supplied by HBPU. Due to the coarse structure and low surface energy of the treated fibers, the fibrous membranes exhibited super hydrophobic properties for the water contact angle high as 156°. The separation capacity for water-in-oil emulsions were up to 7562.24 L·m−2·h−1 for the flux and separation efficiency were up to 99.27 %. Additionally, the flux and separation efficiency exhibited no significant changes over 50 cycles. Therefore, we provided a unique and straightforward technique for producing superhydrophobic separation fibrous membranes.