Preparation of highly interconnected porous poly(epsilon-caprolactone)/poly(lactic acid) scaffolds via supercritical foaming

Highly interconnected porous polymer scaffolds were prepared by gas foaming. Poly(epsilon-caprolactone)/poly(lactic acid) blends were melt mixed and batch foamed using CO2 as a physical blowing agent. The effects of the foaming temperature, pressure, and CO2 saturation time on the foam morphology were related to the mechanical properties of the scaffolds. The cell size in cross section of scaffolds decreased and became more homogeneous until CO2 saturation time reached 1.5hours. With an increase in temperature, the cell size increased markedly and the cell size uniformity decreased gradually, whereas the reverse happened when the foaming pressure was increased. Meanwhile, many open cells can also be detected on the surface of scaffolds. High porosity and an open-cell content of greater than 90% were obtained. The compressive strength of scaffolds was regulated by controlling the foam architecture. The information gathered in this study may provide a theoretical basis for research into porous tissue engineering scaffolds.