Properties of poly(butylene adipate-co-terephthalate)/thermoplastic starch filled with treated and untreated sugarcane bagasse fiber

Sugarcane bagasse, comprising fibrous rind and spongy pith, is frequently employed as a reinforcing agent in both concrete and plastic composites. In thin plastic films, sugarcane bagasse is typically utilized as finely ground particles within the composite film. The integration of this agricultural byproduct into biodegradable plastic films could potentially lower production expenses and promote the film's biodegradability. This study presents the development of poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS) (90/10) formulations incorporating varying loadings of sugarcane bagasse fibers. The impact of alkaline and silane surface treatments on tensile strength, thermal properties, and water barrier properties was investigated. Upon the inclusion of sugarcane bagasse (5%, 10%, 15%, and 20%), a decrease in tensile strength from 23.47 to 8.41 MPa and elongation at break from 1135% to 55.83% was observed. Conversely, the Young's modulus increased from 47.12 to 188.50 MPa following the addition of 20% sugarcane bagasse in the PBAT/TPS matrix. Modest enhancements in tensile properties, thermal characteristics, and water barrier properties were noted after treating the bagasse fibers with alkaline and silane. Scanning Electron Microscope (SEM) analysis revealed that silane-treated sugarcane bagasse exhibited increased surface roughness due to the removal of lignin and hemicellulose, facilitating better adhesion between the fibers and the PBAT/TPS matrix.