Water-Soluble PVA-Based Composite Films for Environmental-Friendly and Sustainable Packaging.

This study develops a new type of poly(vinyl alcohol) (PVA) composite film by incorporating hydrophilic fumed silica and microfibrillated cellulose (MFC) as reinforcing agents through a low-cost synthesis method. The addition of these materials significantly enhanced the film's mechanical properties and hydrophobicity. A three-dimensional network structure formed by hydrogen bonding interactions between PVA, MFC, and silica led to notable improvements in tensile strength (71.1%) and Young's modulus (146%) in the optimal formulation with 5% MFC and 3% hydrophilic fumed silica. Additionally, the composite films exhibited a maximum water contact angle of 90.3°, indicating a significant reduction in the hydrophilicity and the development of a more hydrophobic surface. X-ray diffraction analysis confirmed that the incorporation of MFC and fumed silica enhanced the crystallinity of the PVA films, improving their structural stability. This work demonstrates the synergistic effect of MFC and hydrophilic fumed silica in PVA composite films, offering a promising solution for the development of sustainable packaging materials with improved mechanical and hydrophobic properties.