Summary: | The demand of high-performance filter media for the face masks is urgent nowadays due to the severe air pollution. Herein, a highly breathable and thermal comfort membrane that combines the asymmetrically superwettable skin layer with the nanofibrous membrane has been fabricated via successive electrospinning and electrospraying technologies. Thanks to high porosity, interconnected pore structure, and across-thickness wettability gradient, the composite membrane with a low basis weight of 3.0 g m−2 exhibits a good air permeability of 278 mm s−1, a comparable water vapor permeability difference of 3.61 kg m−2 d−1, a high filtration efficiency of 99.3%, a low pressure drop of 64 Pa, and a favorable quality factor of 0.1089 Pa−1, which are better than those of the commercial polypropylene. Moreover, the multilayer-structured membrane displays a modest infrared transmittance of 92.1% that can keep the human face cool and comfort. This composite fibrous medium is expected to protect humans from PM2.5 and keep them comfortable even in a hygrothermal environment.
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