Development and Optimization of the Extrusion of Potato Peel–Based Biocomposite Films

Abstract

ABSTRACTSide streams from the agricultural and food industries are considered an interesting alternative source for the production of packaging materials due to their composition. However, their use often involves complex and energy‐intensive extraction of individual components. Therefore, this study investigated the application of entire potato peels, without prior extraction, to produce extruded films. Potato peels (PP) and biobased polybutylene succinate adipate (BioPBS) at 1:0, 3:2, 1:1 and 2:3 ratios were used to produce pellets and films in a two‐stage extrusion process. The influence of PP concentration, the addition of maleic anhydride and tartaric acid as compatibilizers and the addition of carnauba wax on the film properties were characterized in terms of morphological, mechanical, physicochemical and thermal properties. Films with a high PP content (50%–100%) showed weak mechanical properties. However, increasing the BioPBS content to PP/PBS 2:3 resulted in a significant increase in tensile strength and elongation at break to 6.20 MPa and 38.09%, respectively, and significantly reduced the water vapour permeability of the film to 5.5 × 10−6 gm/m2 d Pa. The use of 1% maleic anhydride had no significant effect on tensile strength (6.23 MPa), but further increased the elasticity to 65.48%, with no additional effect on barrier properties. The addition of 0.5% tartaric acid showed a similar elongation at break (56.23%) while significantly increasing the tensile strength to 6.56 MPa. The incorporation of 5% carnauba wax increased the surface hydrophobicity of the films from 69.5° to 99.7°, but at the expense of a decrease in mechanical properties.