Montmorillonite nanoclay reinforced carboxymethyl cellulose/stearic acid modified TiO₂ nanocomposites for food packaging applications

In this study, TiO₂-based nanocomposites (NCs) were developed for food packaging applications. Three types of CMC-based NCs were fabricated using different proportions of montmorillonite (MMT), TiO₂ and stearic acid modified TiO₂ (SA-TiO₂). The successful synthesis of NC films was confirmed using FTIR, PXRD, and TGA. The morphology and internal structure of the NCs were studied using SEM and TEM, respectively. Stearic acid modification of TiO₂ was evident by FTIR analysis. CMC as the biopolymer creates an intercalated structure, thus making it nearly a semi-crystalline material. Higher thermal stability was observed in the produced films when CMC is incorporated with SA-TiO₂ and MMT. Also, incorporation of MMT and SA-TiO₂ enhanced tensile strength by three folds in comparison to parent CMC (p < 0.05). In addition, results showed that SA-TiO₂ significantly decreased the water vapor permeability (WVP) at freezing condition and swelling capacity by 44.9% and 33.7%, respectively (p < 0.05). Therefore, the synthesized NC films can be identified as a potential candidate for biodegradable food packaging applications.