Carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVOH) composite films incorporated with glycerol and citric acid were examined for development of biodegradable films with improved water resistance properties. Addition of citric acid at 30% effectively reduced water solubility of the film. To prepare functional active packaging films for storage of perishable products, the role of activated carbon (AC) at different percentages was also investigated. Various physical, mechanical, thermal, and functional properties of these films were then characterized. The study found that the inclusion of AC at 0.25, 0.5, and 0.75% did not affect the tensile strength (TS), elongation at break, and thermal properties, resulting in stronger films. Fourier transform infrared analysis suggested intermolecular interactions within the polymer matrix after incorporation of citric acid and activated carbon. The antimicrobial activity test revealed no inhibition zone; however, there was no noticeable increase or spread of bacteria during the testing period.
James et al. (Thu,) studied this question.