Biodegradable PGA/PBAT Blends for 3D Printing: Material Performance and Periodic Minimal Surface Structures
Zihui Zhang, Fengtai He, Bo Wang, Yiping Zhao, Zhiyong Wei, Hao Zhang, Lin Sang
Abstract
Biodegradable polymers have been rapidly developed for alleviating excessive consumption of non-degradable plastics. Additive manufacturing is also a green energy-efficiency and environment-protection technique to fabricate complicated structures. Herein, biodegradable polyesters, polyglycolic acid (PGA) and poly (butyleneadipate-co-terephthalate) (PBAT) were blended and developed into feedstock for 3D printing. Under a set of formulations, PGA/PBAT blends exhibited a tailored stiffness-toughness mechanical performance. Then, PGA/PBAT (85/15 in weight ratio) with good thermal stability and mechanical property were extruded into filaments with a uniform wire diameter. Mechanical testing clearly indicated that FDM 3D-printed exhibited comparable tensile, flexural and impact properties with injection-molded samples of PGA/PBAT (85/15). Furthermore, uniform and graded Diamond-Triply Periodic Minimal Surfaces (D-TPMS) structures were designed and successfully manufactured via the fused deposition modeling (FDM) technique. Computer tomography (CT) was employed to confirm the internal three-dimensional structures. The compressive test results showed that PGA/PBAT (85/15) D-surface structures bear better load-carrying capacity than that of neat PGA, giving an advantage of energy absorption. Additionally, typical industrial parts were manufactured with excellent dimension-stability, no-wrapping and fine quality. Collectively, biodegradable PGA/PBAT material with good printability has great potentials in application requiring stiffer structures.