Effects of simulated body fluid on the mechanical properties of polycarbonate polyurethane produced via material jetting

A possible tissue substitute material, namely a thermoplastic polycarbonate polyurethane with two different hard-to-soft segment ratios, was produced via material jetting. Since application temperature and media can significantly alter the properties of polymeric materials, it is necessary to understand the impact of both. Therefore, tensile and high-cycle fatigue tests were performed without media as well as immersed in a simulated body fluid. The absorption of phosphate-buffered saline (PBS) led to a decrease in stiffness and tensile strength with a simultaneous increase in elongation at break. For the material with less hard segments, an elevated temperature resulted in a similar effect. More hard segments increase tensile strength and elongation at break. Furthermore, the fatigue behaviour deteriorates significantly with increasing fluid uptake. The fatigue strength of fully saturated specimens decreased by about 20% compared to untreated specimens. An absorption of approx. 20% of the PBS absorption maximum already showed a similar decrease.