Abstract
Bioactive ceramics/poly-L-lactic acid (PLLA) composites have been expected as a material for the bone fracture fixations which have more biocompatibility than monolithic PLLA. In this study, monolithic PLLA and β-tricalcium phosphate (P-TCP)/PLLA composites containing three differentβ-TCP contents (5, 10, 15 wt%) were prepared by injection molding and tested to clarify the effect of hydrolysis and strain rates on the mechanical properties. These composites were immersed in phosphate buffered solution, and then molecular weight measurement and compressive tests at the strain rates ranging from 10"3 to 10"1 /s were performed. Molecular weight of 15 wt% composites were decreased from 154 000 to 91 000. In the results of compressive tests, P-TCP/PLLA composites showed that their Young's modulus have no dependence on the strain rate and their compressive strength increased with increasing strain rates After 24 weeks immersion, compressive strength of composites was decreased.
