Preparation, mechanical properties and in vitro degradation of hydroxyapatite/poly-racemic lactic acid composite

A hydroxyapatite/poly-D, L (racemic) lactic acid (HA/PDLLA) composite was prepared by recombination of liquid-phase adsorption. The mechanical properties of the composite were determined, and the degradation of the composite was investigated via simulation in vitro. Results illustrate that the mechanical properties of the composite are improved with a bending strength of 146.2 MPa, a bend modulus of 2.5 GPa, due to the addition of 10% mass fraction of HA particles into the composite. Compared with pure PDLLA material, the bending strength is increased 9.4 MPa, the bending modulus is increased 0.2 GPa, and the decline of the tensile strength of the composite is not obvious. The mass loss of the 90% PDLLA/10% HA composite was less than 1% during the initial 6 weeks, and the final mass loss was 5.4% at the 12th week. The mass loss of the composite was smaller than that of pure PDLLA material by about 2%-3% in the mid-later period of degradation.