Mechanical behavior of hydroxyapatite-poly(lactic acid) hybrid porous scaffold

Although autologous bone is currently used for repairing bone defects, this method is highly invasive and poses a heavy burden on patients. Thus, the use of artificial bones has been expected. Among the artificial bone materials, bioactive hydroxyapatite (HA) has been attracting much attention. In this research, in order to overcome the problem such as low initial strength of artificial bone after implantation, poly(lactic acid) (PLA) was coated on HA unidirectional porous body prepared by freeze-casting method. In order to investigate the PLA coating method that most effectively improves the mechanical properties, the coating state of PLA was observed and the compression test was performed. As a result of the compression test of the HA-PLA composite porous body, Young's modulus and compressive strength were improved by 79% and 184% respectively at maximum. Furthermore, acoustic emission (AE) measurement was conducted to investigate the fracture behavior during the compression test, classifying the main fracture of HA and HA-PLA porous body as shear fracture.