Biodegradable Starch-Based Nanocomposite Films with Exceptional Water and Oxygen Barrier Properties

Starch, a naturally abundant and biodegradable material, holds great potential for sustainable applications but this potential is often limited by its inherent mechanical weakness and permeability to moisture and gases. In this study, we attempted to overcome those limitations by using MXene nanoplatelets to significantly enhance these properties. By incorporating 10 wt % MXene into starch films, we achieved considerable improvements in mechanical properties, with the Young's modulus and tensile strength increasing to 1923 MPa (from 456 MPa) and 19 MPa (from 10 MPa), respectively. Furthermore, the modified films exhibited a dramatic reduction in water vapor permeability by 92.9% and oxygen permeability by 74.0%, by creating a more efficient barrier that could extend the usability of starch-based materials in various industries such as in packaging materials. Notably, the films retained their biodegradability, decomposing after 6 weeks in soil, underscoring their environmental friendliness. Our findings clearly demonstrate the feasibility of enhancing biopolymer functionalities while maintaining the biodegrability and eco-friendliness of starch, by using MXene nanoplatelets.