The porosity of ptfe nanomembranes can reach 80%~90%, with high porosity and stable microporous structure. PTFE microporous membrane has a fiber interlaced microporous structure, which is stable and effectively intercepts dust particles through biaxial stretching process and high-temperature heat setting treatment. The membrane pore size is small and uniform. PTFE microporous membranes have strong hydrophobicity, low surface energy, and good non adhesion ability, effectively removing dust accumulation on the surface. Washing or blowing back can restore performance and extend service life. The filtration efficiency can reach 99.999995% with low resistance value, which has high filtration efficiency and can meet the requirements of ultra-high efficiency air filter filtration efficiency level. Compared with other filtration materials, PTFE microporous membrane has better filtration performance.