The effect of isocyanate on the properties of poly(butylene adipate‐co‐terephthalate)/Kenaf fiber composites

Abstract Poly(butylene‐adipate‐co‐terephthalate) (PBAT)/Kenaf fiber composites was prepared by the melt processing technique with various compositions to investigate the general properties. While the Young's modulus of the composite was profoundly improved, the tensile strength and elongation at break exhibited a significant diminished with the incorporation of kenaf fibers due to the poor interfacial adhesion between PBAT and Kenaf fibers. The Halpin‐Tsai model was applied, and the similar behavior of Young's modulus for the composite as compared to experimental results was calculated. The micro‐voids and cavitation were clearly confirmed by morphological observation. Reactive compatibilization with HDI improved the compatibility between PBAT and Kenaf fibers, and the mechanical performance was significantly enhanced due to improved interfacial adhesion. The PBAT/Kenaf composites with a reactive compatibilization showed considerable improvement of storage modulus, G′ in terminal region as well. The stable thermal stability could be also beneficial for thermal processing technique. The addition of Kenaf fiber resulted in a liquid‐like behavior decreasing elasticity of the PBAT/Kenaf composites. The HDI had a profound effect on increasing elasticity with solid‐like behavior resulting in enhancing the G′ and η* of the PBAT/Kenaf fiber composites due to the improved interfacial adhesion as confirmed from the morphological observation. Highlights Kenaf fiber has a great effect on improvement of the modulus for PBAT/Kenaf composites The optimized PBAT/Kenaf composite composition is 96/4 wt% ratio for the composite HDI is found to be a good compatibilizer for PBAT and Kenaf fiber Reactive compatibilization enhances the interfacial adhesion between PBAT and Kenaf fiber The compatibilized PBAT/Kenaf composites have the better mechanical performance