Enhancement of the Potato Starch Film Properties from the Incorporation of Itaconic Acid for Sustainable Packaging Applications

Although starch-based films are already being marketed as sustainable alternatives to some commercial plastics, their properties still restrain the widespread use of these materials. To enhance starch (S) film properties, itaconic acid (IA) was employed for the first time at unusual concentrations (5–50 g of IA/100 g of S) and by different forms of incorporation, as a pure additive (no polymerization—N.P.) or by IA polymerization, including pre-polymerization (PreP) and in-situ polymerization (I.S.) during film preparation step. Varying the concentration, it was observed that the addition of higher IA contents increased film crystallinity and decreased water vapor permeability (WVP). The film with 5 g of IA/100 g of S showed an increase in elongation at break (EB) from 18.7 to 45.1%, with no significant changes in tensile strength (TS). Different IA incorporation methods did not affect TS or EB but substantially influenced the barrier properties, and for the PreP technique, WVP was reduced from 2.5 × 10 –10 (control) to 1.7 × 10 –10 g m −1 s −1 Pa −1 . These results suggest that S/IA films can be considered as promising sustainable alternatives to food packaging materials with improved performances. Graphical Abstract