Penetration Performance of Melt-Blown Polypropylene Electret Nonwoven Web against DEHS Aerosols

Abstract

High filtration efficiency of melt-blown polypropylene nonwoven web used as air filter extremely depends on its elelctret characteristics. In this paper, penetration performance of DEHS(diethyl hexyl sebacate) aerosol while flowing through melt-blown polypropylene electret nonwoven web is studied by the method of aerosol penetration measurement as a function of particle size, and the contribution of mechanical and electrostatic mechanism to its capture ability is proposed. The stability of filtration performance after exposure to DEHS for a period of time is measured and the impact of DEHS and other challenge aerosols with different chemical properties on filtration performance is compared. The results show that the higher filtration efficiency of melt-blown polypropylene electret nonwoven web mainly depends on its high electret charge. Aerosol penetration drops off with the increase of aerosol particle size and decreases in the order of basic weight sequence of 20, 40 and 60 g/m2. The most penetration particle size (MPPS) appears at 0.08 m in diameter. The electret charge of the web was cleared away during the course of exposure to challenge aerosol after 5 minutes. The electriferous property of aerosol particle also influences the filtration performance of polypropylene electret nonwoven web. The electret web displays the best filtration performance for ionized aerosol.