Synergistically enhanced mechanical, combustion and acoustic properties of biopolymer composite foams reinforcement by kenaf fibre

This research aims to study the impact of kenaf fibre loadings (20–50 wt%) on the physical, impact, thermal stability and acoustic properties of solid and 3 phr azodicarbonamide (ADC)-foamed polylactic acid (PLA) composites prepared by melt-mixing method. A notable reduction in the bio-composites' density was observed by foaming with ADC. The prepared composites exhibited the highest impact strength of 1.8–2.1 kJm−2 at 30 wt% of kenaf fibre. Moisture absorptions of composites showed an increment trend up to 9–13 %. The energy content measured from combustion testing showed positive effect with respect of kenaf fibre loading and ADC presence. For acoustical absorption, the foamed composites showed a better absorption of about 20 % at 250–1000 Hz and 244 % at 2000–5000 Hz compared to the solid composites containing 30 wt% fibre. This result shows that foamed composite is suitable to be used as a noise level reducer.