Journal of Materials Science

, Volume 54, Issue 6, pp 5112–5126 | Cite as

Fabrication of highly interconnected porous poly(ɛ-caprolactone) scaffolds with supercritical CO2 foaming and polymer leaching

  • Kangkang Zhang
  • Yuqi Wang
  • Jing JiangEmail author
  • Xiaofeng Wang
  • Jianhua Hou
  • Shuhao Sun
  • Qian LiEmail author


Highly interconnected porous poly(ɛ-caprolactone) (PCL) scaffolds combined with supercritical carbon dioxide (CO2) foaming and a polymer leaching process were fabricated by blending PCL with water-soluble poly(ethyleneoxide) (PEO) as a sacrificial material. The effects of foaming conditions and the phase morphology of blend on foaming behavior and pore morphology were investigated. Rheological results and phase morphology indicated that the PCL and PEO were immiscible. For both spherical droplets and co-continuous phase morphologies of PCL/PEO blend, batch foaming experimental results indicated that increasing CO2 saturation time and foaming pressure led to significant decreases in pore size, but increasing temperature led to opposite results. The incorporation of PEO not only facilitated the foaming of PCL by increasing its viscosity, but it also improved the porosity and interconnectivity of the post-leached PCL scaffolds. The porosity improved by up to 93.5%, and the open pore content increased by up to 90.9% for the PCL50 blend (50% PCL by weight). The leaching process had more contribution on the open pore content for PCL/PEO porous scaffolds with co-continuous phase morphologies than for the spherical droplet structures due to different cell-opening mechanisms. The results gathered in this study may provide a theoretical basis and data to support research into porous scaffolds for tissue engineering.



The authors acknowledge China Postdoctoral Science Foundation (contract Grant Number 2017M612415), the International Technological Cooperation Project (contract Grant Number 2015DFA30550) and Key scientific research project plan of Henan high education institutions (contract Grant Number 18A430030) for their financial support of this project. The project was also sponsored by Scientific and technological research project of Henan Province (contract Grant Nos. 182102210188, 172102210489).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

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Supplementary material 1 (DOCX 1754 kb)


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Mechanics and Engineering ScienceZhengzhou UniversityZhengzhouChina
  2. 2.School of Mechanical EngineeringZhengzhou UniversityZhengzhouChina
  3. 3.National Center For International Joint Research of Micro-Nano Molding TechnologyZhengzhou UniversityZhengzhouChina

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