Multi-layered sound absorption structure composed of nonwoven fabrics and polyethylene membranes

This work has focused on the improvement of the sound absorption properties of multilayered structure. Nonwoven fabrics with three different thickness were used to fabricate multilayered absorber. Polyethylene membrane was then incorporated into the multilayered structure with different combinations. The acoustic measurement indicated that polyethylene membrane can improve the sound absorption properties when the thickness of nonwoven fabric is 1.01 mm and 2.38 mm respectively. However, the incorporation of polyethylene membrane will decrease the sound absorption coefficients when the thickness of nonwoven fabric is 3.41 mm. This study has indicated that the thickness of nonwoven fabric and the layer stacking sequence should be focused on consideration to prepare multilayered sound absorber.