Fabrication of Degradable Bone-Like Substitutes Based on Poly-L-lactide and -tricalcium Phosphate

Composite bone-like substitutes composed of poly-L-lactide (PLLA) and -tricalcium phosphate (-TCP) (average particle size: 4.43 m) were fabricated and the properties were investigated. -TCP was prepared by wet chemical precipitation, followed by calcining at 800 degrees C. Composite films were obtained by completely mixing dissolved PLLA with granules of -TCP; the agglomerated -TCP powder granules were distributed homogeneously in the PLLA matrix. PLLA/-TCP composite materials were obtained by cold and hot pressing the composite film at a pressure of 130 MPa and temperature of 185 degrees C-195 degrees C. With increase of the amount of -TCP powder, the bending strength of the composites decreased while the bending modulus increased. The fracture mechanism of the composites was significantly influenced by the content of -TCP powder, from ductile fracture to brittle fracture as the -TCP powder content increased.