STRUCTURE-PROPERTIES RELATIONSHIP IN BIODEGRADABLE NANOCOMPOSITE FILMS BY CAST EXTRUSION

Polylactide (PLA) in one of the most important biodegradable polymers, derived from renewable resources and it can often be an alternative for synthetic plastic materials due its interesting physical properties. However, its toughness, thermal stability, and gas barrier properties are not satisfactory. The field of packaging is one for which the application of polylactide material is highly attractive, and improvements in mechanical and gas barrier properties could allow such polymer to be employed as innovative solution to satisfy the demanding requirements that a modern-day package must fulfill, such as protection, mechanical resistance and biocompatibility. Therefore, it is important to properly modify the PLA in order to improve its properties without losing its biodegradability. In recent studies [1, 3] it was investigated the possibility to modulate the PLA’s properties by filling it with selected additives or by functionalizing the polymer with nanosilicates. This work focuses on the possibility of improving performance properties of polylactide films for packaging applications by melt mixing silicate nanoparticles within PLA matrix. Nanocomposites at various silicate loadings were produced by cast-film extrusion. Oxygen barrier and mechanical properties of the produced films were investigated and correlated to the correspondent nanostructure, fundamental in investigating their potential as packaging films.