abstract
This study evaluates the incorporation of mango leaf extract (MLE) into poly(butylene succinate) (PBS) polymer plasticized with epoxidized linseed oil (ELO) using melt-mixing blending (MMB) and supercritical solvent impregnation (SSI). PBS films were prepared with different ELO concentrations, and a comparative evaluation of the two MLE incorporation techniques (MMB and SSI) was performed in terms of mechanical, physical, optical, chromatic, morphological, and antioxidant properties. The results showed notable differences in films crystallinity (28.03–51.43%) and crystal size (8.47–4.08 nm) depending on the methods used for MLE incorporation, while mechanical properties remained largely unchanged. Scanning electron micrographs revealed surface differences, with a higher accumulation of compounds in films loaded via MMB. Optical and chromatic analyses indicated method-dependent color variations, with films loaded via MMB exhibiting more intense green–yellow tones and SSI-loaded films showing lighter green hues. Both methods increased film opacity and reduced transparency, except for the films plasticized with 5 and 10% of ELO and loaded via SSI, which displayed a distinct optical response. For the antioxidant capacity, films loaded via MMB showed higher oxidation inhibition percentage (OI) (6.31–10.68%OI/mg polymer) compared to SSI-loaded films (3.62–7.89%OI/mg polymer). In the food application study, using freshly cut apples, no significant differences in pH or weight loss were observed; however, fruits packaged with SSI-loaded films exhibited a lower browning index, indicating improved preservation performance. Therefore, the MLE-loaded PBS films loaded by SSI show a better performance for application as eco-friendly active packaging materials.
authors
Ludisbel León-Marcos, Antonio Montes, Diego Valor, Ignacio García-Casas, Carmen S.R. Freire, Carla Vilela, Clara Pereyra
our authors
Carla Vilela
Assistant Professor
Carmen Sofia da Rocha Freire Barros
Coordinating Researcheracknowledgements
This work was also developed within the scope of the project CICECO – Aveiro Institute of Materials, UID/50011/2025 (DOI 10.54499/UID/50011/2025) & LA/P/0006/2020 (DOI 10.54499/LA/P/0006/2020), financed by national funds through the FCT/MCTES (PIDDAC).