Morphological and acoustical characterization of UV-irradiated foam composites from cooking oil and wood flake

Abstract Polymer foam composites for sound absorption with eco-friendly attributes have gained significant attention in sustainable materials research. This study investigates the impact of ultraviolet (UV) irradiation on the morphological, mechanical, and acoustical properties of bio-epoxy (BE) and synthetic epoxy (SE) foam composites, incorporating wood flakes as fillers at varying loadings (0–20 wt%). BE, derived from waste cooking oil, demonstrated superior resilience to UV exposure compared to SE, maintaining better pore structure, mechanical stability, and sound absorption performance. The results show that after 6000 h of UV exposure, BE composites retained 12–18% higher sound absorption coefficient (α = 0.62–0.78) than SE composites (α = 0.50–0.66) at 3000 Hz after 6000 h of UV exposure, demonstrating superior UV resilience. At 6000 Hz, SE outperformed BE (α = 0.45 vs. 0.35) as a result of structural degradation in BE at higher frequencies, attributed to the natural stabilizing properties of bio-based additives. This study proves that BE foam composites offer improved durability and acoustic performance under prolonged UV exposure, positioning them as promising materials for sustainable acoustics applications.