Aplicação da fibra amazônica (Croton lanjouwensis) na produção e caracterização de biocompósitos de PBAT

Abstract

Lignocellulosic fiber-reinforced polymer biocomposites have received increasing attention due to their potential as sustainable materials. Among these reinforcements, Amazonian fibers stand out for their broad availability and competitive structural properties. This study investigated the performance of poly(butylene adipate-co-terephthalate) (PBAT) biocomposites reinforced with pau-caboclo (Croton lanjouwensis) fibers, aiming to relate the characteristics of the fiber to the structural and mechanical properties of the final material. Composites containing 5, 10, 15 and 20 wt% fiber were processed by extrusion and injection molding and characterized by FTIR, XRD, SEM and mechanical testing. The fiber exhibited a semicrystalline structure (Ic = 57.5%), an average diameter of 40.5 μm and a rough morphology that favored mechanical anchoring, although interfacial adhesion remained partial. At the 20% fiber content, a 105% increase in elastic modulus and a 12.3% increase in Shore D hardness were observed, indicating higher stiffness. Tensile strength showed only a slight reduction of 5.5%, whereas elongation at break decreased substantially (82.3%). The results demonstrate that incorporating Croton lanjouwensis produces stiffer biocomposites without significantly compromising mechanical strength. Thus, the study confirms the potential of the species as a natural reinforcement and contributes to the development of biodegradable materials aligned with the Amazonian bioeconomy.