Unlocking the Potential of Polylactic Acid: Exploring Its Thermal and Mechanical Properties for Vitrimerization via Double Reactive Extrusion and Transesterification

ABSTRACT Polylactic acid (PLA) is a biosourced thermoplastic polymer widely used in various fields such as biomedical, packaging, and prototyping. Enhancing PLA thermal and mechanical properties has been a research focus, by transforming it into a vitrimer, a new polymer class. This study demonstrated the effectiveness of a dual reactive extrusion process followed by vacuum compression molding to improve a thermoplastic's properties with vitrimer tendency, using PLA as the main component, diglycidyl ether bisphenol A (DGEBA) as an additive, and zinc acetate as a catalyst. Several characterizations were carried out to assess the thermal, morphological, and mechanical properties of the developed PLA mixtures. Moreover, a kinetic study using three iterative isoconversional integral models (iterative Kissinger–Akahira–Sunose (it‐KAS), iterative Flynn–Wall–Ozawa (it‐FWO), and Trache–Abdelaziz–Siwani) was employed to analyze the effects of the catalyst and DGEBA on the cross‐linking reaction kinetics after the process employed in this work. Results demonstrated the presence of a cross‐linked structure in addition to a promising polymer behavior characterized by enhancements in toughness, ductility, and cross‐linking density by 290%, 127.5%, and 80.5%, respectively. Finally, the optimal composition exhibited almost 96% self‐healing of its surface, demonstrating significant potential for advanced material applications.