Abstract
A novel freeze-gel casting/polymer sponge technique has been introduced to fabricate porous hydroxyapatite scaffolds with controlled “designer” pore structures and improved compressive strength for bone tissue engineering applications. Tertiary-butyl alcohol (TBA) was used as a solvent in this work. The merits of each production process, freeze casting, gel casting, and polymer sponge route were characterized by the sintered microstructure and mechanical strength. A reticulated structure with large pore size of 180–360 μm, which formed on burn-out of polyurethane foam, consisted of the strut with highly interconnected, unidirectional, long pore channels (~4.5 μm in dia.) by evaporation of frozen TBA produced in freeze casting together with the dense inner walls with a few, isolated fine pores (<2 μm) by gel casting. The sintered porosity and pore size generally behaved in an opposite manner to the solid loading, i.e., a high solid loading gave low porosity and small pore size, and a thickening of the strut cross section, thus leading to higher compressive strengths.
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Acknowledgements
This work was supported by the Korea Research Foundation Grant funded by the Korean Government (KRF-2008-313-D00459). Also, this study (Dr. Yang) was financially supported by Pusan National University in the program, Post-Doc. 2009.
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Yang, T.Y., Lee, J.M., Yoon, S.Y. et al. Hydroxyapatite scaffolds processed using a TBA-based freeze-gel casting/polymer sponge technique. J Mater Sci: Mater Med 21, 1495–1502 (2010). https://doi.org/10.1007/s10856-010-4000-1
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DOI: https://doi.org/10.1007/s10856-010-4000-1