Microstructural Design to Improve Shape Memory Behavior of 3D-printed, Poly(L-lactide-co-Glycolide-co-ε-Caprolactone) Scaffolds

Abstract

Biodegradable shape-memory polymers (BSMPs) offer significant potential in biomedical engineering by complex fabrication methods requiring radiation treatment or chemical additives to achieve effective shape-memory behavior. In this study, we present a simple and additive-free strategy to engineer BSMPs with enhanced mechanical and shape-memory performance by tailoring their chain microstructure through controlled two-step ring-opening polymerization. Specifically, poly(L-lactide-co-glycolide-co-ε-caprolactone) (PLGC) terpolymers were synthesized via a two-step approach, exhibiting a block-like architecture compared to one-step synthesis, leading to significantly improved Young’s modulus from 72 to 201 MPa and a more optimal transition temperature (comfortably in the window between room and body temperatures). 3D-printed porous scaffolds fabricated from the two-step P[CL-b-(LGC)] demonstrated superior shape-memory recovery (>90%), essential for effective bone tissue regeneration. These findings highlight the importance of optimizing synthetic strategies to tailor the microstructure to impart control over the properties of PLGC terpolymers, enabling the facile, scalable production of high-performance BSMPs. This approach provides a promising platform for the next generation of 3D biomedical scaffolds for regenerative medical applications.