Development of Natural Fiber Nonwovens for Application as Car Interiors for Noise Control

Abstract

As natural fibers are noise-absorbing materials, renewable and biodegradable nonwovens have been developed using natural fibers such as banana, bamboo, and jute fibers for the automotive interiors to reduce noise, which currently contain traditional materials such as glass and other manufactured fibers and foams that are difficult to recycle. Three types of nonwovens were developed using needlepunching technique by blending bamboo, banana, and jute fibers with polypropylene staple fibers in the ratio of 50 : 50. Sound absorption coefficient was tested by impedance tube method (ASTM E 1050). Comparison of physical properties such as areal density, thickness, stiffness, tensile strength, elongation, structural properties, and comfort properties such as air permeability and thermal conductivity were performed for all samples. It is observed that the bamboo/polypropylene nonwoven with its compact structure showed, higher tensile strength, higher stiffness, lower elongation, lower thermal conductivity, lower air permeability, and good absorption coefficient than others and it is suitable for the automotive interior noise control. At 800 Hz, the absorption coefficient of bamboo/polypropylene and jute/ polypropylene is equivalent to the target level but it is lower by 22% in banana/ polypropylene. But at higher frequencies (1600 Hz), there is a reduction from the target level in all the nonwovens, which could be improved by increasing the thickness of the nonwovens.

Sound absorption properties of bilayered nonwoven composites

“…Rayon activated small pore sized carbon layers combined with a nonwoven layer of cotton, polypropylene and rami fiber mixture, revealed better sound absorption rates [24]. Banana, bamboo and jute fibers mixed with polypropylene, yielded improved sound absorption properties [25]. Composites prepared by mixing short ramie fiber reinforced poly(Llactic acid) composites and flame retardant ammonium polyphosphate and plasticizer poly(butylene adipate-coterephthalate) added ramie fabric/poly(L-lactic acid) composites provided better sound absorption properties [26].…”

Effects of different parameters on acoustic properties of activated carbon fiber felts

“…The occurrence of synthetic fibers expands the field of research as they are exceptional in sound absorption, corrosion-resistance, and are recyclable, of which polypropylene fibers (Alonso et al, 1992;Chen & Jiang, 2007) and polyester fibers (Garai & Pompoli, 2005;Kino & Ueno, 2008b;Tascan & Vaughn, 2008) are the most typical. Fiber composites involve composites of various fibers (Huda & Yang, 2008;Lou, Lin, & Su, 2005;Thilagavathi et al, 2010;Zou, Huda, & Yang, 2010) and composites synthesized by fibers and resin matrix (Jiang et al, 2012;Mueller & Krobjilowski, 2003) which helps to improve acoustic properties and gives full play to multifunctions.…”

Study on Sound Absorption Performance and Transmission Behavior of Perpendicular-laid Nonwovens

“…Nonwovens have very high porosity, high specific surface area, economical price, light weight, good elasticity and a great flexibility in air permeability, they can be presented in a large number of kinds of fiber assemblies, above characteristics decide that nonwovens have been widely applied in thermal insulation and sound absorption field [1].…”