Superhydrophobic Melamine–Formaldehyde Sponge Functionalized by Coupling Agent–Isocyanate Siloxane as Efficient Absorbents for Oil and Organic Solvents

Sponge-like sorbent materials with superhydrophobic/oleophilic properties have drawn significant attention for effective clean-up of oil spills and complex water treatment. However, their cost-effective and high-selectivity adsorption remain a great challenge. Herein, a novel superhydrophobic melamine-formaldehyde (MF) sponge is treated with coupling agent-isocyanate siloxane 3-isocyanatopropyltriethoxysilane (ICPTES) via a urea cross-linking process, and then condensing with hydrophobic silane (dodecyltrimethoxysilane, DTMS) in alcohol solution. The as-prepared Si-MF-DTMS sponge (water contact angle as high as 155.4 degrees) demonstrates favorable chemical and thermal stability in harsh environment, high absorption capacity (74.9-161.4 g g(-1)) for organic liquids, and outstanding separation capability for emulsions. Meanwhile, excellent elasticity and durability allow the organics and oil to squeeze out of the sponge during recycling process easily. Moreover, modified sponge can continuously separate oil and organic pollutants from water by collection device. Thus, a facile, appropriate, and effective strategy used in this work to fabricate superhydrophobic advanced sorbent materials for oil-water separation application is based on surface modification strategy by a coupling agent, which shows enormous potential in oil-spill remediation and industrial chemistry pollution control.