Green fabrication of flame retardant and superhydrophobic materials with application in oil-water separation

Flame-retardant materials with superwettability have received broad attention and research in the field of oil-water separation in recent years. However, it remains big challenging to fabricate flame-retardant and superwettable materials in terms of the complexity and environmental performance. Herein, a non-fluorinated coating containing flame retardants phytic acid/3-aminopropyltriethoxysilane and silica micron-particle/hexadecyltrimethoxysilane was developed. The performance of the coated samples is evaluated by thermogravimetric analysis, limiting oxygen index (LOI), cone calorimetry, and, water contact angle tests. The percentage of residue at 800 degrees C for coated samples (cotton fabric, absorbent cotton, filter paper, cottonwood, packing cardboard) was reduced by 47.6%, 42.2%, 45.5%, 53.2%, and 50.8%, respectively. However, their control samples reduced by 87.4%, 84.6%, 88.4%, 77.2%, and 72.2%, respectively, under the same conditions. The percentage of residue at 800 degrees C for coated samples is much higher than that of the pristine samples. The coated cotton fabric showed excellent flame retardant and superhydrophobic properties. Specifically, the coated cotton fabrics exhibited self-extinguishing properties in the flame burning tests, and the LOI increased significantly from 17.7% to 50.8%. Furthermore, the peak heat release rate and the total heat release values of the coated cotton fabric were significantly declined by 83.4% and 83.6% compared to untreated cotton fabrics, respectively. Additionally, due to its super-hydrophobic surface, the coated cotton fabric exhibited super-strong self-cleaning ability and waterproof performance. The coated cotton fabrics also showed good organic solvent/oil and water separation capabilities while reducing the risk of fire.