Biodegradable PGA/PBAT Blends for 3D Printing: Material Performance and Periodic Minimal Surface Structures

Area of Science:

• Materials Science
• Polymer Science
• Additive Manufacturing

Background:

• Growing demand for sustainable alternatives to non-degradable plastics.
• Additive manufacturing (3D printing) offers a green, energy-efficient method for creating complex geometries.

Purpose of the Study:

• To develop biodegradable polyester feedstock for 3D printing using polyglycolic acid (PGA) and poly (butyleneadipate-co-terephthalate) (PBAT).
• To investigate the mechanical properties and printability of PGA/PBAT blends.
• To manufacture and evaluate complex structures, specifically Diamond-Triply Periodic Minimal Surfaces (D-TPMS), using fused deposition modeling (FDM).

Main Methods:

• Blending of PGA and PBAT in various formulations.
• Extrusion of optimized PGA/PBAT blends into 3D printing filaments.
• Fused Deposition Modeling (FDM) 3D printing of filaments and complex structures.
• Mechanical testing (tensile, flexural, impact, compressive) of printed and injection-molded samples.
• Computer Tomography (CT) for structural analysis.

Main Results:

• PGA/PBAT blends demonstrated tailored stiffness-toughness mechanical performance.
• PGA/PBAT (85/15) filaments exhibited good thermal stability and mechanical properties.
• FDM 3D-printed PGA/PBAT samples showed comparable tensile, flexural, and impact properties to injection-molded counterparts.
• Uniform and graded D-TPMS structures were successfully fabricated with excellent dimensional stability and quality.
• PGA/PBAT (85/15) D-TPMS structures exhibited superior load-carrying capacity and energy absorption compared to neat PGA.

Conclusions:

• Biodegradable PGA/PBAT blends can be effectively processed into 3D printing feedstock.
• The FDM technique is suitable for manufacturing complex structures with these biodegradable materials.
• PGA/PBAT materials demonstrate significant potential for applications requiring stiff, yet biodegradable, components with enhanced energy absorption capabilities.