Natural Fiber Based Lightweight Sound Absorber Materials 2007-01-2197

A variety of synthetic and natural fibers are commonly used in the construction of sound absorbers for automotive applications. Sound absorbers incorporating these fibers are produced by a variety of manufacturing processes. These manufacturing processes generally utilize synthetic or natural fibers that have a starting length of 25mm or greater. The final sound absorber may also incorporate very long yarns, filaments or pieces of partially opened textiles referred to as shoddy. Largely absent from commercial automotive sound absorbers are high levels of short natural fibers, whose length is generally less than 3mm. The focus of this work was to evaluate the sound absorption performance of materials comprised primarily of short natural fibers. The data showed that sound absorbers utilizing a majority of short natural fibers could provide equivalent sound absorption at a lower weight than traditional structures using longer fibers.