Polyvinyl alcohol-based sustainable packaging films incorporating glycerol monostearate: Fabrication, characterization, and intermolecular interactions analysis

Polyvinyl alcohol (PVA) is a promising biodegradable polymer for sustainable packaging. However, its strong hydrophilicity limits practical applications. This study reports the fabrication of PVA films modified with glycerol monostearate (GMS) to address this limitation. Films containing 5%, 10%, and 15% GMS were systematically characterized by rheology, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The analyses revealed strong molecular entanglement and high compatibility between GMS and PVA, which significantly enhanced film hydrophobicity. At 15% GMS loading, the films exhibited improved water and gas barrier properties, with a water contact angle (CA) of 127.18°, a water absorption capacity (WAC) of 6.35 g/g, a water vapor transmission rate (WVTR) of 8.82 g/m 2 /d, and an oxygen transmission rate (OTR) of 58.14 (cm 3 ×cm×cm 2 ×s×Pa) -1 . Moreover, the incorporation of GMS enhanced ultraviolet (UV)-shielding performance (average UV transmittance: 75.66%) and increased tensile strength to 75.84 MPa. Molecular dynamics (MD) simulations corroborated these findings, revealing stable intermolecular hydrogen bonding that reinforced the film network. Collectively, these results underscore PVA-GMS films as high-performance, eco-friendly packaging materials with superior water resistance, barrier functionality, and mechanical strength. The hydrophilic regions of glycerol monostearate (GMS) form intermolecular hydrogen bonds with polyvinyl alcohol (PVA), while its hydrophobic regions migrate to the film's surface, effectively enhancing its water resistance. • Hydrogen bonding and molecular entanglement between PVA and GMS increased hydrophobicity. • MD simulations verified the hydrogen bonding and van der Waals forces of PVA and GMS. • The modified PVA films had promising potential in food packaging applications.