Controlled preparation of porous poly (ether-ester) scaffolds

Ladder-like and well-interconnected porous scaffolds were fabricated from poly (ether-ester) poly (butylene terephthalate)-co-poly (cyclohexylene dimethyl terephthalate)-b-poly (ethylene glycol)) (PTCG)-dioxane (DO) systems by means of a combination of freeze-drying and thermally induced phase separation (TIPS) technique. The effect of experimental parameters on scaffold morphology was also investigated. The results show the pore size and porosity of scaffolds decrease with the increasing of polymer concentration, and the size of pore on the top surfaces towards air is larger than that on the bottom surfaces towards glass because of different coarsening process. The pore size reaches a maximum at 0°C with the decrease of quenching temperature because of the interaction between thermodynamic driving force and resistance to demixing rise during the process of phase separation. The addition of H₂O into DO, which lead to the increase of demixing temperature, might facilitate the pore size to expand. The results suggest that the morphology of PTCG scaffolds could be adjusted to some extent by varying experimental parameters.