Sound Absorption Properties of Oil Palm Fibre–Polylactic Acid-Based Micro-Perforated Panels with Compatibilizer

Micro-Perforated Panels (MPP) are widely recognized for their effectiveness in passive noise control, relying on submillimetre perforations to achieve sound absorption without traditional fibrous fillers.The shift towards sustainable materials has prompted the exploration of bio-composites incorporating natural fibres for acoustic applications.Oil palm fibre (OPF), a by-product of agricultural waste, offers a renewable and biodegradable reinforcement when integrated with polylactic acid (PLA) to form Bio-Composite MPPs (BC-MPP).This study aims to investigate the acoustic and mechanical performance of BC-MPP fabricated from OPF/PLA composites with a compatibilizer.A systematic approach encompassing material fabrication, tensile testing, Scanning Electron Microscopy (SEM), and Sound Absorption Coefficient (SAC) analysis was adopted to assess the influence of fibre content and air gap variation.BC-MPP achieved a maximum SAC of 1.00 at 1530 Hz with 30% OPF and a 10 mm air gap.With increasing air gaps (20 mm and 30 mm), SAC values of 0.99 were recorded at 970 Hz and 800 Hz, respectively.Mechanical analysis showed a reduction in tensile strength at higher OPF contents, attributed to fibre pull-out and interfacial voids.This study presents an eco-friendly acoustic solution using agrowaste-derived composites.Future work will explore fibre surface treatment and hybrid reinforcement strategies to optimize both acoustic and mechanical performance.