TCP/PLA複合材料の力学的特性に及ぼす延伸の影響

抄録

Poly(lactic acid) (PLA) attracts much attention as a material of bone fixation device which is used for fracture treatment. However, the material has drawbacks, such as lower elastic modulus and no osteoconductivity. On the other hand, the bioactive ceramics has higher stiffness and osteoconductivity. In this study, PLA and β-tricalcium phosphate (β-TCP) which is one of bioactive ceramics were compound. And, β-TCP/PLA composite was drawn to improve the strength. The purpose of this study is to clarify effect of drawing on mechanical properties of β-TCP/PLA composites. PLA and β-TCP/PLA composites were tensile tested under drawing temperature. As a result, β-TCP/PLA composites deformed to deformation ratio of about 2.5 under drawing temperature of 70 °C. The drawing conditions were determined from this result to drawing temperature of 70 °C and drawing ratio of 1.5. The mechanical properties of drawn PLA and β-TCP/PLA composites were measured by tensile test under room temperature. As a result, the tensile strength of PLA and β-TCP/PLA composites increased respectively from 59.3 MPa and 40.1 MPa to 64.8 MPa and 59.9 MPa by tensile drawing. On the other hand, there were no significant differences in elastic modulus due to drawing. Therefore, the increase in tensile strength of β-TCP/PLA composites was larger than that of PLA. And, the tensile strength of β-TCP/PLA composites reached the same strength as that of PLA by drawing at drawing condition in this study.