Numerical Study on Parameters Affecting the Structure of the Scaffolds Prepared by Freeze-Drying Method

Freeze-drying is one of the mostly used methods for preparing scaffolds and is very sensitive to the material and operational parameters such as nucleation temperature, thermal properties of the mold, cooling rate, set freezing point and slurry height. In the present study, a finite element method (FEM) based code was developed to investigate the effects of such parameters and to eventually predict the microstructure of the scaffold. Similar molds and cooling condition used in various experimental studies were exactly simulated and the result showed that there was a pore size distribution pattern, uttering scaffold morphology completely in accordance with experimental results. The achieved pattern demonstrated how different thermal condition tailored scaffold microstructure. Besides, it was shown that nucleation temperature (T_n) was an effective parameters controlling the final structure of the scaffold. This framework can be used to optimize scaffold structure or any ice templating method.