Mechanical properties and degradation properties in vitro of carbon fiber reinforced hydroxyapatite/polylactide composite

A novel composite of carbon fiber (CF) reinforced hydroxyapatite (HA)/ploylactide (PLA) degradable biomaterial was developed by solvent blending. The mechanical properties and degradation properties in vitro of the composite were researched. The CF/HA/PLA composites have excellent mechanical properties. As the hydroxyapatite mass fraction increases, there are respectively peak values with flexural strength and flexural modulus, including maximums of flexural strength of 430MPa and flexural modulus of 26GPa. After degradating in vitro for 3 months, the flexural strength and flexural modulus fall 30% and 36% respectively. The SEM photos indicate that the degradation begins from the interfaces of the composite, after degradating, there are gaps at the interfaces, and the water uptake increases to 5%, but the mass loss is only 1.6%. The pH values of the PBS drop less than 0.1, which can do some favors to the recoveries of the fracture. The results show that the mechanical properties of the composite can meet the requirements of internal fracture fixation.