Multifunctional Melamine Formaldehyde Composite Foam for High-Temperature Insulation, Flame Retardancy, and Oil–Water Separation

Melamine formaldehyde (MF) foams, although widely used in heat insulation and as flame retardants due to their unique combination of low thermal conductivity and high flame retardancy, are prone to rapid collapse, which is extremely dangerous. Herein, we report a hydrophobic composite foam with a hierarchical structure. This foam was prepared through in situ incorporation of palygorskite and sodium alginate (Pal-SA) composite aerogels into the MF foam via the ambient pressure drying method and then through methyltrimethoxysilane (MTMS) chemical vapor deposition. The composite foam exhibited high-temperature thermal stability, excellent flame retardancy, and low smoke emission (2.5 m2/m2), which is ∼17 times lower than that of the pure MF. The foam prepared in the present work has excellent application prospects in offshore oil-spill treatment, high-temperature insulation, and flame retardancy. Moreover, the results of this work may provide guidance for developing low-smoke flame-retardant materials.