Effect of Almond Skin Waste and Glycidyl Methacrylate on Mechanical and Color Properties of Poly(ε-caprolactone)/Poly(lactic acid) Blends

• Published in: Polymers Vol. 15; no. 4; p. 1045
• Main Authors: Valdés, Arantzazu, Dominici, Franco, Fortunati, Elena, Kenny, Jose María, Jiménez, Alfonso, Garrigós, María Carmen
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20.02.2023; MDPI
• Subjects: 3-D printers; Acids; Agricultural wastes; almond skin residues; Biocompatibility; Biodegradability; Biodegradable materials; Biomedical materials; Blending; By products; color properties; Compatibilizers; Composite materials; Elongation; Environmental impact; Food packaging; Food packaging industry; Formulations; glycidyl methacrylate; Heat resistance; Impact strength; Mechanical properties; Mixtures; Nanoparticles; Outdoor air quality; PCL/PLA blends; Polycaprolactone; Polylactic acid; Polymerization; Polymers; Prunus amygdalus; Skin; Tensile strength; Waste treatment; Yield strength; Spain; PCL/PLA blends; color properties; Prunus amygdalus; glycidyl methacrylate; mechanical properties; almond skin residues
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/polym15041045

Blending Poly(lactic acid) (PLA) and Poly(ε-caprolactone) (PCL) is a promising strategy to enhance the properties of biodegradable materials. However, these compounds are thermodynamically immiscible and, consequently, compatibilization is required during polymer blending. Reinforced biocomposites can be obtained by adding agricultural wastes generated by industries which are forced to consider waste treatment methods to prevent environmental concerns. Novel PCL/PLA blends were proposed based on the addition of 10 wt.% almond shell (AS) waste combined with 3 wt.% glycidyl methacrylate (GMA) as a compatibilizer. Different PCL-, PLA-, and PCL/PLA-based blends at different percentages (75:25, 50:50, 25:75, 15:85) added with GMA and AS were obtained. The color results highlighted the lower transparency and brownish tone of the studied formulations after the addition of AS. The addition of PCL provided a positive effect on PLA's ductility due to its intrinsically higher flexibility. The combination of GMA and AS improved the mechanical properties of PCL, PLA, and 50:50 controls by reducing yield strength, yield strength at break, and elongation at break values. The 75:25_GMA_AS formulation showed a homogeneous visual appearance, low transparency, and desirable mechanical properties for rigid food packaging applications, reducing the final material cost through the revalorization of AS.