Preparation and filtration properties of electrospun poly(vinylidene fluoride)-polyacrylonitrile/melt-blow polypropylene nonwoven composite filtration materials

The high filtration efficiency and low flow resistance of air filtration materials were successfully prepared by composing electrospinning poly(vinylidene fluoride) (PVDF)-polyacrylonitrile (PAN) nanofibers with polypropylene(PP) melt-blown nonwoven. The influence of the PVDF to PAN mass ratio on the solution properties, morphology, specific surface area and filtration properties were investigated. The results show that when the PVDF to PAN mass ratio is 3:5, the solution has excellent spinnability and the well-distributed nanofibers with mean diameter of 0.59 μm can be formed. BET test result shows that it goes for nearly double the specific surface area when PVDF to PAN mass ratio decreases from 2:1 to 3:5. Besides, the filtration efficient and resistance determined by TSI 8130 filter were tested. Results reveal that electrospinning PVDF-PAN nanofibers can significantly improve the filtration performance of polypropylene melt-blown nonwovens, the filtration efficiency of PVDF-PAN/melt-blown PP nonwoven reaches to 99.95%, significantly higher than that of melt-blown nonwoven with 65%, the filtration resistance is 77 mm H₂O (1 mm H₂O=9.8 Pa), the filter quality factor reaches 0.0987, which is more higher than 0.0168 of melt-blow nonwoven. The filtration properties significantly enhance by composing electrosping PVDF-PAN nanofiber with melt-blow nonwoven.