Effect of Alkali Treatment and Particle Size on Sound Absorption Coefficient of Particleboards Made from Oil Palm Frond

This study uses an experimental approach to illustrate the significance of particle size and alkali-treated on the sound absorption coefficient of oil palm frond (OPF) particleboard. Two variables were investigated: Particle size and one hour of NaOH treatment of oil palm frond. The particleboard was manufactured based on OPF material with 10% urea-formaldehyde as the binder and 1% NHCl4 as the hardener. The mixing of OPF with UF was pressed under hot-pressing of 9 tons at 140°C for 5 minutes to obtain OPF particleboard. 100 mm and 29 mm diameter of OPF particleboard were fabricated with three different particle sizes in the constant density of 0.4 g/cm³ and thickness of 10mm. Three particle sizes were fine, medium, and coarse particle sizes with a diameter of 0.2-0.6, 1-2, 2.4-4.8 mm, respectively. The SAC was determined using a two-microphone impedance tube following ASTM E 1050 at frequencies 50 to 6400 Hz. The single rate number, noise reduction coefficient (NRC), the mean of arithmetical values for the SAC at four-octave bands frequency (250, 500, 1000, and 2000), was determined. The data from experimental and calculation were obtained and investigated.