Aromatic Copolyesters Based on Poly(butylene furanoate) and Poly(butylene isophthalate) for Small-Diameter Vascular Applications

Fabrication of small-diameter vascular grafts remains a major clinical challenge due to thrombosis and poor long-term patency of existing synthetic materials. In this study, a family of aromatic homo- and copolyesters based on poly(butylene 2,5-furanoate) (PBF) and poly(butylene isophthalate) (PBI) was processed into electrospun scaffolds for vascular tissue engineering. The electrospinning process enabled the fabrication of defect-free flat and tubular scaffolds with tunable fiber morphology and alignment closely resembling native vascular architecture. Thermal analysis confirmed the preservation of the polymers' intrinsic semicrystalline structure and stability, with PBI and PBI-rich copolymers showing enhanced thermal resistance. Mechanical testing revealed elastic modulus, burst pressure, and strain at failure values comparable to those of the saphenous vein, indicating their suitability for vascular replacement. From the biological point of view, PBF scaffolds promoted endothelial cell adhesion and proliferation, favoring endothelialization, while PBI-rich materials reduced platelet adhesion and maintained normal coagulation parameters, highlighting their favorable intrinsic hemocompatibility. Overall, these aromatic polyesters combine mechanical robustness, endothelial compatibility, and antithrombotic behavior, demonstrating strong potential as next-generation biobased materials for small-diameter vascular grafts.