The ptfe washable filter membrane prepared by one-way or two-way stretching method has a spider web-like microporous structure on the surface. The three-dimensional structure has very complex changes such as network connectivity, hole nesting, and channel bending. Therefore, it has excellent surface filtration function. Nano-masks produced using this material have the characteristics of high barrier efficiency, long service life, lightness and breathability, and are a new direction for the development of masks in the future.
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