Acoustic performance of pineapple leaf fibres bonded with natural rubber latex as a sound absorber

Abstract

This paper investigates the sound absorption properties of pineapple leaf fibre (PALF) bonded with natural latex. Three mixtures with 90%, 80% and 70% PALF bonded with latex of 10%, 20%, and 30%, respectively were selected for the fabrication of the sound absorber boards with a thickness of 20 mm. A board sample with 100% PALF content was also fabricated as a control sample. All sample boards were prepared by pressing using a hot press. All sound absorbers boards samples were evaluated in terms of density, porosity, Sound absorption coefficient (SAC), and noise reduction coefficient (NRC). It was found that the higher the content of PALF, the density of the specimen decreases while the porosity increases slowly. It was determined that all the specimens studied had a density of less than 300kg/m3 which is within the permissible range as a sound insulation material. All PALF specimens bonded with latex showed good SAC at a frequency of 1250 Hz (over 0.5). It was found that 90%PALF:10% latex has an NRC above 0.5, exceeding the synthetic sound absorbers available on the market and the natural sound absorbers previously studied. This sound absorption is due to the latex binder which also acts as a sound dampener and the reduction of porosity which results in a reduction of porosity and causes an increase in the number of sound waves reflected by the composite, which increases the SAC. Therefore, latex-bonded PALF has excellent sound absorption performance, with a high potential to be used as a sound absorber.