Robust superhydrophobic resin sponges modified by polydimethylsiloxanes/epoxy-based copolymer for high-efficiency oil/water separation

Abstract The development of recyclable, durable and widely adaptable porous hydrophobic materials is of vital importance for the effective separation of leaking oil-water mixtures. Herein, we functionally modified melamine formaldehyde resin sponge (MFRS) with PMMA, PDMS-PMMA and PDMS-PGMA via a facile solution-immersion process. Compared with PMMA-coated MFRS, the improvement of the water contact angle (WCA) and oil-water mixture separation efficiency of PDMS-PMMA/MFRS were sufficient enough to verify that the introduction of PDMS block enhanced the hydrophobic performances of the material. Moreover, the importance of the GMA block in PDMS-PGMA/MFRS was confirmed by the excellent performance of the material in oil-water separation recycling experiments, with 91.5% separation efficiency after 8 runs. The fabricated PDMS-PMMA/MFRS with improved WCA (155°) and oil-water mixture separation efficiency (99.1%), demonstrated superhydrophobic property, which is attributed to the introduction of hydrophobic block PDMS and coating-induced surface geometric folds. Besides, the acid-resistance and widely adaptable (efficient separation of various oil-water mixtures) performances of PDMS-PGMA/MFRS were experimentally confirmed. The freely available manufacturing raw materials and facile functionalization process of PDMS-PMMA/MFRS offers possibilities for its adoption in the efficient cleanup of oil spills.