Disposable face masks (single use face masks) are produced from polymers such as polypropylene, polyurethane, polyacrylonitrile, polystyrene, polycarbonate, polyethylene, or polyester. They consist of three layers; an inner layer (soft fibers), middle layer (melt-blown filter), and an outer layer (nonwoven fibers, which are water-resistant and usually colored). The melt-blown filter is the main filtering layer of the mask produced by the conventional fabrication of micro- and nanofibers, where melted polymer is extruded through tiny nozzles, with high speed blowing gas
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