Abstract

Poly(lactic acid) (PLA) is the most widely used bio-based and biodegradable polymer in the food packaging sector, due to its market availability, competitive cost and ease of processing. However, PLA has some limitations in terms of its mechanical, thermal and barrier properties, which can be improved by adding inorganic particles to the polymer matrix to obtain hybrid organic-inorganic composites with improved properties. Among all the inorganic particles, Halloysite Nanotubes (HTH) and Diatomaceous Earth (DT) are of special interest because their hollow structure offers the possibility of incorporating active agents inside them to be released in a sustained way to the food, extending their shelf life. In the present work, rosemary (Rosmarinus Officinalis) essential oil was encapsulated in the cavities of NTH and TD, the active particles were incorporated into a PLA polymeric matrix and processed by extrusion followed by cast-film process to simulate industrial conditions. The presence of NTH and TD improved the Young's modulus of PLA, while rosemary oil acted plasticising the system increasing the elongation at break allowing flexible films to be obtained. The obtained materials showed antioxidant capacity, demonstrating the potential to produce biodegradable active materials of interest in the food packaging sector.