Flexibility Enhancement of Poly(lactide-co-glycolide) for Fused Deposition Modeling Technology

Abstract

Poly(lactide-co-glycolide) (PLGA) is one of the most widely used bioplastics in bioengineering and has been actively applied to fused deposition modeling (FDM)-based 3D printing. However, the brittleness of PLGA remains a major obstacle to its application in FDM systems, because these systems can only process flexible materials. Here, we developed a new technique to enhance the flexibility of PLGA. A polymer drawing process involving bidirectional extension was applied to induce molecular alignment, which affects the flexibility of the material. Filamentous forms of PLGA with various draw ratios were prepared and their material properties were investigated in detail. The results showed that PLGA flexibility was markedly increased at the draw ratio of 3, which was identified as the brittle-to-ductile transition point. The elongation at break of the drawn PLGA at this draw ratio was approximately 14 times greater than that of the raw material. Printability tests showed that various complex 3D structures could be fabricated with the drawn PLGA using a FDM system. In addition, the drawn PLGA showed no cytotoxicity in culturing. The technique developed here shows potential for the preparation of long and flexible PLGA filaments for use in FDM technology with biological applicability.