Solvent-Based Recycling of EVOH and Silica Nanoparticle Incorporation for High-Performance Packaging Nanocomposite...

Multilayer packaging films offer excellent functional performance, but their complex architecture hinders recyclability and creates a major challenge for sustainable packaging applications. Among their constituent layers, EVOH is a high-value barrier polymer that is critical for achieving superior gas barrier properties, yet its effective upcycling remains difficult. In this work, we evaluate the feasibility of upcycling dissolution-recycled EVOH into blown films by incorporating 0.1-0.5 wt % SiO₂ nanoparticles. Comprehensive thermal, mechanical, morphological, rheological, and barrier characterization identified 0.1 wt % SiO₂ as the optimum loading, where well-dispersed nanoparticles promoted strong polymer-filler interactions and increased crystallinity, as supported by FTIR, XRD, and XPS. In this composition, the films showed improvement in stiffness, strength, and toughness, along with improved thermal stability and much better barrier performance, which reduced the effectiveness of reinforcement by limiting polymer-filler contact. These results demonstrate the feasibility of converting dissolution-recycled EVOH into high-performance nanocomposite blown films, while emphasizing that filler loading must be optimized to achieve consistent reinforcement in solvent-reprocessed EVOH blown films.