Fabrication and characterization of antimicrobial starch‐based nanocomposite films and modeling the process parameters via the RSM

The main aim of this study is the design and fabrication of degradable nanocomposite films composed of starch/gelatin (S/G)/SiO₂ suitable for food packaging applications. Response surface methodology (RSM) was applied to design the fabrication process and to investigate the effect of S/G weight ratio and SiO₂ weight percent (wt.%) on the mechanical and barrier properties of the prepared samples. The results revealed that tensile strength and modulus were increased with increasing S/G wt. ratio and introducing SiO₂ into the polymer matrix, while elongation at break and water vapor permeability (VWP) decreased. The process optimization was done and various properties of the optimized films such as morphological properties, thermal properties, VWP, degradability, and antibacterial properties were investigated. It was found that the thermal stability of the optimized sample as well as its barrier property against water vapor were improved dramatically as SiO₂ presented into the matrix due to proper dispersion and interaction of nanoparticles with the polymer matrix as also confirmed via scanning electron microscopy images. Furthermore, SiO₂ has brought significant antibacterial properties for the S/G matrix that is a notable feature for food packaging films. Overall, the results of the current study confirm the S/G/SiO₂ compounding could be proper candidate for fabrication of antibacterial degradable food packaging films. POLYM. COMPOS., 39:E584–E591, 2018. © 2018 Society of Plastics Engineers