Ternary blends of thermoplastic starch (TPS) with poly(lactic acid) (PLA) and poly(butylene succinate-co-adipate) (PBSA): Design and processing.

This article investigates a ternary blend of thermoplastic starch (TPS), polylactic acid (PLA), and polybutylene succinate-co-adipate (PBSA) for producing compostable films and semi-rigid containers via extrusion and thermoforming. The study demonstrates that incorporating 25 wt% TPS into a PLA/PBSA (4:9 ratio) matrix yields films with good mechanical strength, adequate stiffness, fair oxygen barrier properties, and a high disintegration rate under ambient composting conditions. However, thermoformed containers made from this blend exhibit limited thermal resistance, performing well up to 80°C but deforming upon contact with hot liquids at 100°C, likely due to the low melting point of PBSA. The research highlights enhanced crystallinity after reprocessing, contributing to mechanical performance and compostability, while noting sensitivity to moisture and certain chemicals linked to TPS content. These findings suggest potential applications in sustainable food packaging, balancing biodegradability with functional requirements.