Abstract:

In order to prepare filter with low resistance performance under the same filtration effficiency, the combined melt-electrospinning and hot-pressing device was used to prepare fiber packing density gradient composite filters with polypeopylene (PP) sa raw material. Firstly, the filtration efficiency of the composite filters perpared under defferent rolling-up speeds was studied. It is found that the filtration efficiency of composite fileters decreases with the increase of the rolling-up speed. Secondly, three rolling-up speeds were selected to prepare three fiber nets with the same thickness, and their packing densities were calculated. Finally, the fiber nets with different packing densities were combined with PP spun bonded nonwoven to pripare gradient filters. The results show that the obtained composite filters with gradient have low resistance under the same filtration efficiency.  In addition, the filtration efficiency of particles with a particle size greater than or equal to 2.0 μm is 87.0 %, the filtration resistance is 8.0 Pa,and the air permeability is 187.0 mm/s.

Key words: melt-electrospinning, polypropylene, fiber packing density, gradient filter material, filtration property