Analytical and Experimental Characterization of theMechanical Behavior of β-TCP/PLLA Compositesunder Tensile and Flexural Loading

摘要

Bioactive ceramics, β-tricalcium phosphate (β-TCP), particles reinforcedbioabsorbable plastics, poly-L lactide (PLLA), composites have been expected toapply to the fracture fixations which have more biocompatibility than monolithicPLLA． In this study， β-TCP/PLLA composites containing three different β-TCPcontents (4.8, 9.5, 14.3wt%) were prepared by injection molding. The results ofbending test indicate that the bending strength of composites decreased and thebending modulus of those increased with increasing β-TCP contents. The effect ofβ-TCP content on the tensile strength and modulus also show the same tendency ofthat on bending properties. Nevertheless, the tensile strength is half of bendingstrength. The results of fracture surface observation showed that initial fracture of thecomposites was caused by debondings between β-TCP agglomeration and PLLA. Inaddition, predictions of tensile stress-strain curves based on damage mechanics werein good agreement with the experimental results. The analytical results for flexuralstress-strain curves were calculated considering the movement of neutral plane．