Study On Preparation And Performances Of Meltblown Non-Woven Fabric And The Characterization Of Specialized Polypropylene

The environment pollution of the earth is getting more and more serious, and the air pollution is receiving increasing attention. Particles generated by cars and industries in the air do serious harm to people's health. Therefore, the development of high efficiency filter to prevent the human body from those hazards in the air is becoming increasingly urgent. Melt-blown non-woven fabrics are widely used in the field of air filtration in recently years because of its characteristics of ultra-fine fiber, large specific surface area, high porosity, high-performance of deep filtration, low air resistance, and easy to produce. So high performance meltblown nonwoven filter supply falls short of demand.The die swell of melt at the spinet caused serious fibers folding phenomenon which could greatly decrease the efficiency of the nonwoven by enlarge the average diameter of the fiber and mesh size of the nonwoven. In order to improve the equipment of the meltblown line, the die swell behavior of PP specialized for prepare meltblown nonwoven has been studied in this paper. As a result, the die swell behavior of PP is depended on comprehensive effects of various factors. Such methods as using high-MFI PP, improving the process temperature and enlarging the length/diameter ratio can be taken to diminish the die swell behavior of PP and decrease the folding and diameter of the fibers.The M-PP meltblown nonwoven takes advantages of soft handle and high strength. However, the PP obtained by degradation is not fit for specialized material for fabricate nonwoven because of the unstable quality. The dynamic viscoelasticity of both kinds of PP specialized for fabricate nonwoven have been compared, and the differences of both kinds of PP behaviors at the frequency and temperature change have been analyzed. The results could play directive function in material choosing.The studies of preparing melt-blown non-woven fabric have shown that the performance of the fabric is closely related to a variety of technological factors such as the air temperature, air pressure, die temperature and DCD. Those factors influence the performance of non-woven by affect the fiber diameter and density.