Unveiling the Potential of Borassus flabellifer’s Leaves Derived ZnO Nanoparticles in Augmenting the Attributes of PLA-Surface Modified Nanocellulose Bio-composite

The utilization of synthetic plastics has resulted in environmental and human health concerns. Consequently, there is a growing focus on developing eco-friendly alternatives like polylactic acid (PLA). Nonetheless, its drawbacks include slow crystallization, vulnerability to UV radiation, and absence of antibacterial properties. One potential strategy involves integrating nano-cellulose (NC) and metal oxide nanoparticles into PLA to enhance its antibacterial features and mechanical robustness. The NC was extracted from the leaves of Borassus flabellifer and further treated with lactic acid to obtain surface-modified NC (SMNC). Besides, the Zinc oxide nanoparticles (ZnO NPs) were green-synthesized using the B. flabellifer leaves extract and further characterized through various analytical techniques such as SEM, XRD, and FTIR. The optimized bio-composite ratio was 89.5 mg of PLA, 3.5% (w% of PLA) of SMNC, and 7% (wt% of PLA) of ZnO NPs based on the appearance, water contact angle (WCA), and antimicrobial activities of the bio-composite film. The PLA-SMNC-ZnO NPs film was further characterized and compared with PLA and PLA-SMNC films for its structural, mechanical, and thermal properties. The PLA-SMNC- ZnO NPs film exhibited an improved tensile strength of 13.9 MPa and Young’s modulus of 0.00689 GPa than PLA and PLA-SMNC. Also, the thermal stability of PLA-SMNC-ZnO NPs film was 320 °C from TGA. Additionally, PLA-SMNC- ZnO NPs film exhibited reduced water absorption and improved resistance to UV radiation. In conclusion, these findings validate the potential of the ZnO NPs derived from B. flabellifer’s leaves in improving the versatility of PLA. Graphical Abstract