Structure-Property Relationships in PBAT Biocomposites Reinforced with Kenaf Bast and Core Fibres

The incorporation of natural fibres in biodegradable polymer composites presents a sustainable method for enhancing material performance. This study examined the impact of incorporating kenaf bast fibre (KF) and kenaf core (KC) on the mechanical and thermal properties of poly(butylene adipate-co-terephthalate) (PBAT) composites. Increasing the KF and KC content resulted in enhanced stiffness and hardness of the composites; however, this also led to a reduction in their tensile strength and deformability. However, the composites demonstrated a greater elastic modulus compared to unfilled PBAT. Differential scanning calorimetry indicated that the incorporation of KF and KC affected the glass transition temperature (Tg), crystallisation temperature (Tc), and melting temperature (Tm) of PBAT. SEM analysis indicated moderate interfacial adhesion, characterised by localised fibre pull-out and debonding, which suggests partial stress transfer. Overall, PBAT/KF composites exhibited enhanced mechanical and thermal performance relative to PBAT/KC composites, especially regarding stiffness. These findings underscore the potential of kenaf bast fiber-reinforced PBAT for use in lightweight engineering components and sustainable packaging applications that necessitate improved stiffness. It is recommended that additional research be conducted on water resistance, barrier properties, biodegradability, migration, and biocompatibility to support advanced applications.