Reconciling the ease of processing with the final performance of materials is an important challenge in technology, esp. for medical devices. Thermoplastic polyurethanes can be processed by various solution casting techniques including electrospinning and electro-3D-writing. In our invention, we introduce the innovative concept of self-reinforcement of these polymers, which enable a facile processing into various shapes, e.g., artificial blood vessels; Excellent mechanical properties are attained through post-processing, just by storing the constructs under physiological conditions.