Recovery of Rose Flower Waste to Formulate Eco-Friendly Biopolymer Packaging Films.

Considering the circular principles of materials and investigating the possibility to use waste materials before their final disposal, in this work, dry rose flower (DRF) and rose flower waste (RFW), after oil extraction, have been considered as suitable materials for the formulation of biopolymer packaging films. Both DRF and RFW particles have been characterized by spectroscopy analysis, and their radical scavenger ability has been investigated. Moreover, DRF and RFW particles have been added by melt mixing to PolyLactic Acid (PLA), and formulated PLA-based films have been studied through rheology analysis, mechanical test, differential scanning calorimetry, and microscopy observations. Finally, the influence of both DRF and RFW particles on the photo-oxidation behavior of PLA has been evaluated by subjecting thin films to UVB exposure, and the progress of degradation has been monitored following the accumulations of oxygen-containing groups in time. Obtained results suggest that both DRF and RFW have a beneficial effect on the photo-oxidation behavior of PLA, and they can slow down PLA degradation upon UVB exposure. Therefore, PLA-based composite materials could be considered a good candidate for applications as packaging films.