Commercial polydimethylsiloxane modified melamine sponge for highly efficient oil-water separation

• NH2-PDMS-modified melamine sponges exhibit high hydrophobicity and exceptional oil absorption capacity, ranging from 46 to 155 times their own mass. • The modified sponges achieve oil-water separation efficiencies exceeding 98.2%, demonstrating outstanding performance for oily wastewater treatment. • The material retains its separation efficiency without obvious degradation after 10 cycles, indicating robust reusability and stability. • The molecular mass of PDMS on the sponge surface significantly tunes material properties, offering a strategy to optimize oil-water separation performance.