Magnetically-responsive starch nanocomposites for potential recovery of plastic waste: Characterization of starch/clay/Fe3O4/TiO2 film

Abstract

This study addresses the environmental and economic challenges of plastic waste recycling by developing magnetically recyclable starch-based bionanocomposites (SCFT). The hypothesis that intercalating Fe₃O₄ and TiO₂ nanoparticles within a layered clay matrix (CFT) would maintain magnetism while reducing dark coloration was tested. Structural analysis confirmed SCFT formation, with uniform dispersion at low CFT content and aggregation at higher concentrations. Increased CFT content reduced moisture absorption, water solubility, and contact angle, but did not significantly alter mechanical properties and water vapor permeability. The composites retained a dark color, indicating the intercalation strategy was insufficient to overcome this limitation. However, SCFT films exhibited effective magnetic separation and UV-blocking capability. Therefore, while clay intercalation does not mitigate the dark coloration of the magnetic particles, it yields a functional, magnetically recoverable packaging material with UV-blocking properties.