Fabrication and characterization of soluble soybean polysaccharide and nanorod-rich ZnO bionanocomposite

• We Developed a novel bionanocomposite for packaging based on SSPS.
• ZnO nanorod (ZnO-nr) improved heat sealability and barrier properties of SSPS films.
• SSPS/ZnO-nr have excellent antimicrobial activity against Gram-positive bacteria.
• SSPS with low concentration of ZnO-nr had 0% UV transmittance.

In this study, a novel bionanocomposite film was prepared by the casting method. Different concentrations [i.e., 0%, 1%, 2%, and 4% (w/w)] of nanorod-rich ZnO (ZnO-nr) were incorporated into soluble soybean polysaccharide (SSPS). The mechanical, thermophysical, antimicrobial, and barrier properties of the resultant bionanocomposite films were evaluated. Incorporation of 4% ZnO-nr into the SSPS matrix reduced water vapor permeability from 8.19 × 10−11 to 5.25 × 10−11 (g m−1 s−1 Pa−1) and oxygen permeability from 223 to 127 (cm3 μm m−2 day−1 atm−1). The elongation at break and heat seal strength of the films increased by over 20%. The moisture content, glass transition temperature, and tensile strength of the SSPS films significantly decreased by ZnO-nr incorporation. SSPS/ZnO-nr (4%) films showed 0% UV transmittance and were able to absorb over 70% of the near-infrared spectrum. The SSPS/ZnO-nr films exhibited excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus. In summary, ZnO-nr is an excellent potential filler for SSPS-based films used as packaging materials.