4D-printed PLA-PETG polymer blends: comprehensive analysis of thermal, mechanical, and shape memory performances

This article investigates the thermal, mechanical, and shape memory performances of 3D-printed polylactic acid (PLA), polyethylene terephthalate glycol (PETG), and their blends for potential applications in 4D printing. Differential Scanning Calorimetry reveals distinct glass transition temperatures for PLA-PETG blends, confirming their immiscibility. The integration of PETG alters the crystalline structure of PLA, shifting its behavior from brittle to ductile. This confirms PETG's function as an effective plasticizer. The tensile strength and Young's modulus are influenced by material composition and printing orientation. The results show that 75% PLA and 25% PETG blend demonstrated enhanced mechanical properties compared to other polymer blends. Shape memory experiments demonstrate exceptional fixity and recovery rates, reaching 100%, with the 75% PLA blend exhibiting outstanding performance across 15 cycles. These findings, coupled with insights into the impact of programming temperature, offer valuable perspectives for designing 4D-printed structures with shape memory attributes, unlocking innovative applications across diverse fields.