Pyris 1 tga

First, we checked the structure and chemical composition of the stent material. We used TGA and TGA-GCMS to determine the chemical composition and SEM analysis to assess the material structure.
During TGA, we heated the samples to 600°C at a rate of 10°C/min. The samples were measured in an open platinum crucible in a synthetic air atmosphere (20 ml/min). The samples were measured in an air atmosphere to determine polydioxanone’s thermal stability in this atmosphere. TGA was performed on a Pyris 1 TGA (PerkinElmer, USA).
During TGA-GCMS, we heated the sample to 300°C at a rate of 10°C/min. The samples were measured in an open platinum crucible in a nitrogen atmosphere (20 ml/min; Linde N2 4.6). In TGA-GCMS, a nitrogen atmosphere must be used to protect the mass spectrometer’s heated wolfram filament from oxygen. The TGA-GCMS was performed on a Pyris 1 TGA, GC Clarus 680, and MS Clarus SQ 8T (all PerkinElmer, USA).
We inspected the filament material’s homogeneity, looking at the internal structure using SEM investigation. The samples were prepared by mechanically rupturing the filaments by simply cracking them with tweezers, mounting them on the SEM stub using carbon adhesive tape, and directly (without an additional coating to prevent charging) visualizing them using field-emission SEM (FE-SEM JEOL JSM 7500F, Japan) and the in-lens secondary electron detector.

A thermogravimetric analyzer (TGA 1-Pyris, PerkinElmer, Inc., Waltham, MA, USA) was used to determine the thermal degradation of the polymers at the temperature employed in HME and 3D printing techniques. The samples were loaded in aluminum pans and heated from 50 to 500 °C at a rate of 20 °C/min. Ultra-purified nitrogen was used as a purge gas at a flow rate of 25 mL/min. The data were collected and analyzed using the PerkinElmer Pyris™ software (Waltham, MA, USA), and the percent mass loss was calculated.