Effect of carboxymethyl cellulose and montmorillonite addition on the physicochemical and thermal properties of basil seed mucilage-based biodegradable film

The aim of this study was optimization and improvement of the physic-chemical characteristics films based on basil seed mucilage (BSM) and carboxymethyl cellulose (CMC) (100, 162.5 and 225% w/w the mucilage) using montmorillonite (MMT) (0 and 8% w/w the mucilage) by casting method. The produced films properties were evaluated for thickness, moisture content, density, mechanical properties, Fourier Transform Infrared Spectrometer (FTIR), and thermogravimetric analysis (TGA). Results indicated that thickness and density of the films were not significantly influenced by CMC and MMT addition (p>0.05), but the moisture content of nanocomposites decreased with increasing CMC content (p<0.05). Presence of CMC and MMT in the film matrix caused to enhancement of ultimate tensile strength (UTS) and elongation at break (EB) in nanocomposites; the maximum of UTS and EB with the values of 27.9 MPa and 41%, respectively, were obtained for the nanocomposite made by 225% CMC and 8% MMT. FTIR spectra revealed no new compounds resultant from the chemical interactions, and only some shifts were observed for some peaks, and also slightly weakening or intensifying in several peaks. TGA plots showed that incorporation of CMC and MMT led to improvement of thermal properties. In conclusion, simultaneous loading of nanoclay and CMC generated the improved nanocomposites, and the treatment loaded with both MMT and the maximum level of CMC (T7) is advised as the best film for employing in the food packaging.