Elastomers with tunable degradation as small diameter blood vessel substitutes for peripheral artery disease

Cardiovascular diseases are responsible of a huge number of severe disability cases and deaths worldwide. Among these, Peripheral Arterial Diseases (PAD) represent a major clinical challenge, especially when they affect the lower limbs, often leading to critical limb ischemia (CLI), impaired mobility, and increased risk of amputation. Strong research in this field has been extensively carried out, in particular for the associated complications, such as the occlusion of small diameter (< 6 mm) vessels. This PhD research focused on the synthesis, characterization, and processing of innovative polymeric materials for the fabrication of small-diameter (d < 6 mm) vascular grafts aimed at treating PAD. Two distinct families of polyesters, aliphatic (based on poly(butylene trans-1,4-ciclohexanedicarboxylate) (PBCE)) and aromatic (based on poly(butylene 2,5-furandicarboxylate) (PBF) and poly(butylene isophthalate) (PBI)), were designed and synthesized through targeted copolymerization strategies to tailor their physical, chemical, and biological properties. The aliphatic copolymers incorporated Pripol 1009 to modulate flexibility, degradability, and surface properties. These materials showed thermoplastic elastomeric behavior, tunable degradation rates, and excellent hemocompatibility. Electrospun scaffolds supported endothelial cell adhesion and maintained stability over time, with mechanical performance, especially for PBCE-based blends, comparable to that of the saphenous vein. Parallel efforts have been directed to aromatic PBF/PBI systems, chosen for their inherent thermal and chemical stability. Copolymerization effectively enhanced toughness without compromising long-term integrity. These materials also showed low cytotoxicity, reduced protein adsorption, and promising hemocompatibility. Electrospun scaffolds preserved endothelial cell viability and expression of VE-cadherin, while mechanical tests on tubular scaffolds confirmed their suitability for vascular applications. Overall, both material systems show strong potential for vascular tissue engineering: PBCE-based copolymers for short-term regenerative purposes, and PBF/PBI-based systems for long-term vascular grafts.