Extension of shelf-life of mangoes using PLA-cardanol-amine functionalized graphene active films

Multifunctional PLA films were fabricated through the solution casting method by incorporating cardanol oil (CA) and amine-functionalized graphene (AFG). The effect of the CA, and AFG on the structural, mechanical, thermal, thermo-mechanical and antioxidant properties of PLA films were investigated. FTIR analysis of PLA-CA films showed distinct peak positions at 1590 cm^-1 corresponding to the aromatic C=C aromatic bond of CA, showing that CA is compatible with the PLA. The XRD analysis reveals that CA reduced the intensity of the PLA peak at 16.8° and the AFG enhanced the sharp intensity of the same peak. The surface morphology of CA and AFG inclusion films showed the uniform dispersion of fillers into the PLA matrix. The tensile properties of CA inclusion film showed increased elongation by 153 %, and AFG enhanced the tensile strength by 35 % compared to neat PLA. The thermal properties, such as DSC and TGA curves, showed that the CA and AFG influenced the T_g and T_m values of the fabricated PLA films. The antioxidant activity of PLA films was significantly enhanced by 28 and 12 times for CA and AFG inclusion films, respectively and showed moderate antimicrobial activity against Salmonella typhi (MTCC-733) bacteria. The developed PLA active films enhanced the shelf-life of mangoes by 15 days.