Fig. 6. Swelling and degradation behavior of 3D-printed materials.

Representative microscopy images of a printed PTMPTCX scaffold immersed in 5 M NaOH over 15 min, demonstrating surface-erosion behavior of the denoted strut (red circle) immediately upon immersion in the solution (a), at 5 min (b), 10 min (c), and 15 min (d). Representative curves of uniaxial testing of polycarbonate-derived material films immersed in 5 M hydrolytic degradation solution at 37 °C, with samples deformed 50 µm at 1 Hz until failure (e) and corresponding static gravimetric degradation analysis at the same conditions (f), along with in vitro strut erosion measurements from microscopic analysis of printed scaffolds immersed in 5 M NaOH at 37 °C (g). Post-implantation assessment of sample swelling (h) and gel fraction (i) were used to assess the extent and type of degradation of the samples after removal from tissue at discrete timepoints, with accompanying measurements of strut diameters from printed scaffolds ex vivo (j). Scale bar = 200 µm. Data are presented as mean values with error bars = standard deviation (n = 6).