Rapid prototyping of polyurethane for the creation of vascular systems

A precise control over the internal architecture was essential for manufacture of complex organs. To create vascular systems that mimic human livers, we designed and fabricated complex 3D objects with an intrinsic network of interconnected channels. A new elastomeric polyurethane, mainly based on polycaprolactone and poly( ethylene glycol) with excellent biocompatibility and tunable biodegradation properties, was used to fabricate these vascular systems using a low temperature deposition system based on the layer-by-layer manufacturing principle. A specific model was selected via computer aided design ( CAD), solid free form fabrication processes are conducted under computer direction. Two example object patterns were produced by precision controlled dispensing of a biodegradable polyurethane into 3D multi-micro-tunnels with multi-micro-pores at a low temperature (-28 degrees C). The design and fabrication strategies used to create physical objects directly from CAD models represent a promising route for the establishment of complex organ vascular systems.