Sustainable and High-Performance Polylactide/Polycarbonate Blends with Enhanced Toughness and Thermal Stability via Stereocomplexation and Phase Continuity

High Resolution Image Download MS PowerPoint Slide Durable polylactide (PLA)-based materials are highly pursued for replacing conventional petroleum-based plastics. However, developing a tough and heat-resistant PLA blend remains a significant challenge. Herein, a series of high-performance PLA-based blends were prepared through melt blending of bio-based polycarbonate (PC), poly( d -lactic acid) (PDLA), and a compatibilizer (BPM). Phase morphology, crystallization behavior, mechanical properties, and thermal resistance were systematically analyzed. A novel dual heat-resistant network was constructed, comprising a continuous PC phase and PDLA/PLA stereocomplexation. In this network, the stereocomplexation creates a 3D network restricting the amorphous PLA chain mobility, while the PC phase acts as a heat-resistant framework, collectively enhancing thermal stability. Moreover, the addition of BPM enhances the toughness and interfacial adhesion between PC and PLA phases, resulting in substantial improvements in mechanical properties. The optimized blend achieved a heat deflection temperature of 106.5 °C, an impact strength of 7.5 kJ/m 2, and an elongation at break of 113.6%.