Boosting phosphorus–nitrogen–silicon synergism through introducing graphene nanobrick wall structure for fabricating multifunctional cotton fabric by spray assisted layer-by-layer assembly

Efficient construction of quaternary composite coating on cotton fabric was presented by spraying aqueous solutions of graphene oxide, 3-aminopropyl triethoxysilane, sodium alginate and ammonium polyphosphate for providing the flame retardant, antimicrobial and antistatic properties. The thermal degradation of cotton was monitored by thermogravimetric analysis and the result showed the introduction of graphene oxide (GO) as a nanobrick wall structure can greatly boost the phosphorus–nitrogen–silicon synergism. The flame retardance performance was evaluated by vertical burning test and microscale combustion calorimetry, which indicated that the assembly coating eliminated the afterglow during combustion and decreased the pHRR value. Particularly, (GO1)₁₀ cotton fabric has a significant self-extinguished effect with a pHRR value of about 3.2% of uncoated cotton, and moreover, can effectively inhibit the growth of E. coli and S. aureus. Furthermore, it also keeps highly reliable flame retardant and antistatic ability during the washing test. This simple and green approach provides new insights into the fabrication of cotton fabrics with multifunction including flame-retardant, antimicrobial and antistatic properties in a large scale.