Application of non-woven materials in automotive acoustic parts and automotive interiors

First, we introduce the application of non-woven materials in automotive acoustics. The non-woven material composed of random fibers contains countless narrow and connected pores. When the vibration of the air particles caused by sound waves propagates in the pores, friction and viscous resistance will be generated, so that the sound energy is converted into heat energy. absorb. Therefore, this type of material has excellent sound-absorbing properties, and many factors such as thickness, fiber diameter, fiber cross-section and production technology will affect this performance. Non-woven materials are mainly used for engine cover lining, instrument panel, roof liner, door inner liner, trunk cover and liner and other parts, which can improve the NVH performance of automobiles. Next, explain the three main forming processes of nonwoven materials: meltblown process, needle punch process and airlaid process. In the melt-blown process, polypropylene and polyester are used as raw materials, and polypropylene is melt-extruded and blow-melted into long fibers. After cooling, it is mixed with polyester short fibers to obtain finished products with high sound absorption coefficient, light weight and good thermal insulation. The air-laid process uses air flow to aggregate a variety of fibers on the web-laid curtain. This method can produce high-thickness materials, and can improve the material properties by adjusting the ratio of each component. The needle punching process is a physical processing method that uses repeated puncturing of the fiber web to reinforce the very fluffy fiber web into a cloth with certain properties, which has the characteristics of no pollution and recyclable scraps. Finally, for the frontiers in the field of nonwoven materials, we share the innovative solution of Dow Chemical Meltblown Polyethylene. Polyethylene is a common resin. It has the characteristics of low melting point, weather resistance, flexibility, and energy saving. It is a good candidate for meltblown materials. However, the polyethylene resins currently on the market cannot provide the high melt index required by the meltblown process, so it is difficult Produce the expected superfine fiber. The meltblown polyethylene resin ASPUNTM MB recently developed by Dow Chemical uses the innovative metallocene catalyst INSITETM process to create the industry's first high-melt index polyethylene resin with a viscosity of up to 18000CP. Compared with polypropylene meltblown materials, polyethylene meltblown materials have higher tensile strength and ductility, better durability, excellent processing characteristics, less odor, soft and comfortable hand feeling, and are a potential automotive interior material .