Preparation and Characterization of Triglycine-Containing 3D-Printed PBAT/PLA Specimens

This study explores a novel additive0.2 wt % monodisperzed H-Gly-Gly-Gly-OH (triglycine)to poly-(1,4-butylene adipate-<i>co</i>-1,4-butylene terephthalate)/polylactide (PBAT/PLA) blend. The triglycine-containing PBAT/PLA was extruded into uniform filaments with a diameter of 1.74 ± 0.02 mm by using a single-screw extruder, which was subsequently employed to fabricate specimens via material extrusion (MEX) technology at nozzle temperatures (<i>T</i>) of 155 and 190 °C. In the present study, the fabrication of triglycine-containing specimens was investigated with a focus on elucidating their thermal behavior and mechanical properties. The influence of print temperature on these properties was also evaluated to establish correlations between processing conditions and material performance. Results indicated that all specimens could be printed smoothly at 155 and 190 °C, regardless of triglycine presence. The addition of triglycine did not significantly affect the melting temperature of the specimens, but it did reduce the difference in glass transition temperature between PLA and PBAT. SEM analysis did not display any significant differences between the specimens across all nozzle temperatures. Specimens without triglycine displayed consistent mechanical properties across temperatures, achieving a high tensile modulus (<i>E</i>) of 261.5 MPa for specimens printed at <i>T</i> = 190 °C. Conversely, triglycine-containing specimens printed at the same temperature exhibited a significantly lower tensile modulus (<i>E</i> = 159.5 MPa). However, the triglycine inclusion enhanced the ultimate tensile strength at lower print temperatures, with values of 15.03 ± 0.11 MPa for specimens printed at <i>T</i> = 155 °C compared to 10.16 ± 1.65 MPa for specimens printed at <i>T</i> = 190 °C.