Concentration-dependent anti-/pro-oxidant activity of natural phenolic compounds in bio-polyesters

In this work, the potential of several naturally occurring phenolic compounds, such as Ferulic Acid (FA), Vanillic Acid (VA), Vitamin E (VE) and Quercetin (Q), as stabilizers against the photo-oxidative degradation of Polylactic acid (PLA) has been assessed. Specifically, PLA-based films containing different amounts of considered stabilizers have been formulated and their photo-stability under UVB exposure has been evaluated. The preliminary characterization of the formulated films shows that all used stabilizers exert plasticizing action, as probed by rheological analysis, due to their low molecular weight. Moreover, no significant modification of the PIA crystallinity has been noticed in presence of used natural compounds.