Effects of Kenaf Fiber Strand Treatment by Sodium Hydroxide On Sound Absorption

Abstract

ABSTRACT Natural fiber capability as an acoustic panel is subjected to physical properties of the fiber. Chemical treatment was implemented in this study to improve kenaf fiber performances and utilized as a sound absorption material. This research aims to use sodium hydroxide (NaOH) treatment from 1% to 8% concentrations on kenaf fiber. Physical changes on the kenaf fiber strands due to NaOH treatment were observed using Scanning Electron Microscope (SEM). The subsequent effects on sound absorption were measured using Impedance Tube to determine the sound absorption coefficient (SAC) and noise reduction coefficient (NRC) values. Findings show that the diameter of kenaf fiber gradually decreased with the increment of the NaOH concentration. The eliminations of the hemicellulose and lignin layer of the strands causing the decreased of the strand diameter which was proven by FTIR analysis. Results from SAC shows that treated Kenaf fiber using 6%, 7%, and 8% of NaOH obtained higher SAC at high frequency range (>2500 Hz). Those samples obtained 0.67 coefficients for their NRC value. This research concludes the sound absorption capabilities of kenaf absorber was better using thinner strands and the 6% NaOH concentration was the optimum concentration to treat kenaf fiber for sound absorber.