Ring-Opening Polymerization of Fused Salt-Templated non-Eutectic and Eutectic Mixtures for Biodegradable Macroporous Scaffolds

Abstract

The low-temperature and organocatalyzed ring-opening polymerization (ROP) of eutectic and non-eutectic mixtures of L-lactide (LLA) and ε-caprolactone (CL) was conducted under solventless conditions using lactates as sustainable initiators. This approach successfully yielded biodegradable three-dimensional (3D) macroporous scaffolds via a fused salt-templated process. To gain insight into the eutectic formation in LLA-CL mixtures, density functional theory (DFT) modeling was performed. Additionally, structural characterization through NMR, X-ray diffraction, and DSC confirmed the successful ROP, and formation of semicrystalline scaffolds via a fused-salt templating process. Mechanical testing revealed that scaffold strength and elasticity could be tuned by adjusting molecular weight and crystallinity of the polyesters. Hydrolytic degradation studies showed gradual weight loss, consistent with scaffold composition. Furthermore, cytotoxicity evaluations demonstrated that the scaffolds exhibit suitable biocompatibility, making them promising candidates for tissue engineering purposes.