Development of biocomposite for food packaging application using poly vinyl alcohol nutmeg short fiber: Load bearing, antimicrobial, dielectric and hydrophobicity

This work investigates the development and comparison of alkali-treated and silane-treated nutmeg short fiber-reinforced PVA films, with a focus on their mechanical, dielectric, and antimicrobial properties. The silane-treated film (TNS3), reinforced with 10 vol% nutmeg short fibers, demonstrated superior mechanical properties, including a tensile strength of 137 MPa, 84% elongation at break and a 4.9 J impact strength. These improvements are attributes to the enhanced interfacial bonding between the fibers and PVA matrix, which facilitates better stress distribution and resistance to deformation. The TNS3 film also exhibited favourable dielectric characteristics, with a dielectric constant of 6.3 and a low loss factor of 0.04, reflecting the optimized fiber-matrix interaction that minimizes energy loss, making it suitable for electronic and insulation applications. Additionally, a higher water contact angle of 73° suggests improved hydrophobicity due to the silane treatment, which enhances the film’s moisture resistance and stability in humid conditions. In contrast, the alkali-treated films showed improved antimicrobial properties, likely due to the removal of certain fiber components such as lignin and hemicelluloses, which exposes more reactive sites, boosting antibacterial and antifungal activity. These properties make the silane treated composites suitable for high strength packaging, moisture resistant coatings and dielectric/insulation applications due to their superior mechanical, hydrophobic and electrical properties. Whereas, the alkali-treated composites are ideal for antimicrobial food packaging, medical textiles and hygienic applications owing to their enhanced antibacterial activity and adequate mechanical performance.