A super soft thermoplastic biodegradable elastomer with high elasticity for arterial regeneration.

Elastomers with innovative performance will provide new opportunities for solving problems in soft tissue repair, such as arterial regeneration. Herein, we present a thermoplastic biodegradable elastomer (PPS) that differs from the rigid, low-elastic traditional ones. It shows super softness (0.41 ± 0.052 MPa), high stretchability (3239 ± 357 %), and viscoelasticity similar to natural soft tissues. In addition, it also has good processability and appropriate degradability, estimated at 4-8 months for complete degradation in vivo. This excellent overall performance makes it a great support material for soft tissue repair and a powerful modifying agent for improving existing materials. For example, introducing it into poly(l-lactide) scaffolds through thermally induced phase separation can create a unique microporous structure with interconnected large pores (diameter >10 μm), demonstrating high efficiency in inducing cell infiltration. Blending it with poly(ε-caprolactone) through electrospinning can produce a composite fibrous film with significantly improved comprehensive performance, displaying artery-matched mechanical properties. Building on the above, we constructed a tri-layer tissue-engineered vascular graft for arterial regeneration, exhibiting promising remodeling outcomes in rabbits.