Poly(lactic acid)-Based Films with Functionalized Mesoporous Silica from Rice Husk for Sustainable Food Packaging

The current investigation endeavors to address the inadequate ductility and suboptimal gas barrier properties of poly(lactic acid) (PLA) by producing composites of PLA with functionalized mesoporous silica (PLA/0.6SPA-MPS-ACN) through the solution casting method. MCM-41 (MPS) mesoporous silica is synthesized from rice husk (RH) via the sol-gel method and modified with a biosurfactant, sucrose palmitate (SPA), and again functionalized with anthocyanin (ACN). This study investigates how nanofiller weight percentages affect PLA's structural, morphological, thermomechanical, and barrier characteristics. BET analysis reveals a decrease in pore volume and surface area subsequent to the modification of MPS with SPA and ACN. The morphological analysis provides evidence of the uniform dispersion of filler within the PLA matrix at a loading of up to 5 wt %. The structural characteristics, thermal stability, and crystallization properties of PLA/0.6SPA-MPS-ACN composites are examined by using FTIR, XRD, TGA, and DSC analysis, respectively. All composite films have lower UV-visible light transmission than PLA. Mechanical investigations show that PLA/0.6SPA-MPS-ACN (5 wt %) films significantly improve tensile strength, yield stress, and tensile modulus values by similar to 55, similar to 88, and similar to 89%, respectively. The OTR data show that adding 0.6SPA-MPS-ACN (5 wt %) to the PLA matrix reduced the O-2 transmission rate by similar to 52%. The Nielsen model fitted PLA composite diffusion data with a lower 0.6SPA-MPS-ACN loading.