Artichoke Bracts and Stems Residues as Active Filler for Poly(Butylene Succinate-Co-Adipate) (PBSA) Composites: From Agro-Waste to a New Sustainable Material

Abstract

In the context of a growing bioeconomy and the drive for sustainable materials, new biocomposites were formulated by incorporating poly(butylene succinate-co-adipate) (PBSA) with residues from artichoke harvesting, specifically bracts and stems, which were shredded to an appropriate size. The chemical composition, thermal stability, and biochemical properties of the two fillers were first determined. Both fillers were found to contain lignocellulosic compounds, such as cellulose and hemicellulose, and to be rich in secondary components, such as polyphenols, with known antioxidant activity. A maximum filler amount of 20 wt% was employed in the composite preparation by melt compounding. The resulting composites were evaluated for their mechanical properties, water interaction, photo-oxidative stability, antibacterial activity against two target strains, Escherichia coli and Staphylococcus aureus, and fragmentation in soil. The results demonstrated that incorporating 10 wt% of either filler (bracts or stems) provided the most favorable balance of properties, yielding adequate mechanical properties, enhanced photo-oxidative resistance, strong antibacterial activity, and fast fragmentation in soil.