A snadwich-like flame retardant nanocoating for supersensitive fire-warning

Huali Xie, Xuejun Lai*, Hongqiang Li,  Jiefeng Gao, Xingrong Zeng*, Xiaoyi Huang, Shifeng Zhang

Abstract:  In this study, we proposed an ingenious strategy to fabricate supersensitive fire-warning coatings for large-area combustible materials, which is a challenging yet urgent necessity. A novel sandwich-like flame retardant nanocoating based on graphene oxide (GO), silver nanowire (AgNW), and fluoride polyvinyl butyral (FPVB) was fabricated via spray-coating. Owing to the quick thermal reduction of the GO nanosheet and the vertical micron-sized conductive path in the sandwich-like structure, the prepared nanocoating exhibited the most sensitive fire-warning response reported thus far (0.83 s), even on large-area substrates. Meanwhile, the nanocoating endowed the combustible substrates with outstanding flame retardancy. The limiting oxygen index of the coated polypropylene and wood were as high as 31.5% and 42.0%, respectively, and the samples exhibited the self-extinguishing property in the horizontal and vertical burning tests. Besides, owing to the superhydrophobicity of the top layer, the nanocoating exhibited exceptional self-cleaning performance and water resistance. Thus, this work provides a new and efficient method to significantly enhance the fire safety of flammable materials, exhibiting practical applications in transportation, housing, and electric appliances.

论文链接：https://doi.org/10.1016/j.cej.2019.122929