A superhydrophobic and flame-retardant cotton fabric fabricated by an eco-friendly assembling method

A novel eco-friendly and durable superhydrophobic and flame-retardant cotton fabric with fluorine-free, halogen-free was prepared via step-by-step dip-coating and spraying technology. At first, common cotton fabric was impregnated in the flame-retardant ethoxysilane-terminated phosphate polyurethane. Afterwards, methanol mixture containing silica nanoparticles, methyl triethoxysilane, and dihydroxy-terminated polydimethylsiloxane was sprayed on the surface of the cotton fabric. Finally, a flame-retardant cotton fabric with micro-nano rough surface and low surface energy was formed. The resulting superhydrophobic and flame-retardant cotton fabric exhibited superamphiphobicity with the contact angle and sliding angle of 160° and 6°, respectively, while flame retardancy with limited oxygen index of 28.1%. and flame self-extinguishing. Furthermore, this superhydrophobic and flame-retardant cotton fabric showed robust superhydrophobicity and flame-retardancy after undergoing 1000 cycles of abrasion, 60 min of ultrasonic washing and 50 standard machine washing cycles, in sequence, indicating its potential as a multifunctional protective textile fabric. Additionally, the method proposed in this study can effectively solve durability and environmental problems currently faced by the coated fabric with superhydrophobicity and flame-retardancy.