Abstract:

In order to solve the contradiction between the filtration efficiency and the filtration resistance of the air filter membrane, the polypropylene composite electret fiber membrane under different process conditions were prepared by melt differential electrospinning combined with electret technology, and the morphology characteristics, charging capacity and filtration performance thereof were characterized. The results show that with the increase of tourmaline content, the fiber membrane tends to be gray from white, and the color of fiber membrane is gradually deepened. The same kind of electric charges repel each other, enduing the fiber woth open and loose structure, appearing slightl projection in the fiber morphology to effectively reduce filtration resistance. The added tourmaline effectively improves the charging capacity and filtration performance of the fiber. When the tourmaline content is 2%, the comprehensive effect is the best, and the charge storage stability is good. The filtration efficiency of particle size amaller than 0.3 μm is 99.23%, and the filtration resistance is 8.6 Pa.

Key words: polypropylene fiber membrane, electrospinning, electret, melt differential, charge capacity,  filtration performance