Effects of sintering temperature on physical and compositional properties of α-tricalcium phosphate foam

Effects of sintering temperature on the physical and compositional properties of α-TCP foam fabricated using the polyurethane foam method were examined. When a polyurethane foam coated with α-TCP slurry was sintered at 1,400-1,550°C, α-TCP foam having basically the same fully interconnected porous structure was produced although shrinkage occurred with increasing sintering temperature. On porosity of the α-TCP foam, a higher foam porosity of 95% was obtained when sintered at 1,400°C as compared to the 90% porosity obtained at a higher sintering temperature of 1,550°C. Further, at 1,500°C or higher temperature, frame became dense with disappearance of micropores. On compressive strength, it increased from approximately 50 to 250 kPa when sintering temperature was increased from 1,400 to 1,550°C. Nonetheless, no compositional changes were observed even when the α-TCP foam was cooled in the furnace without quenching process. In light of the results obtained, it was concluded that α-TCP foam fabricated using the polyurethane method was useful as a bone substitute and/or scaffolding material for tissue engineering. Besides, α-TCP foam could be useful as a precursor for the fabrication of other calcium phosphate foams.