Development of carbon nanotube reinforced hydroxyapatite bioceramics

Abstract

This paper reports development of a production method to create a composite material that is biocompatible, which will have high mechanical strength and resilience, and be able to withstand exposure to the physiological environment. The chemical precipitation conditions necessary for the production of single phase synthetic hydroxyapatite (HAp) have been determined. Neutron and X-Ray diffraction have been used extensively to follow the effects of drying and heat treatments on the process and to confirm that the final material is single phase. The neutron diffraction data has enabled the positions of the hydroxide bonds to be determined. Subsequent development of a technique to produce a HAp + carbon nanotube composite material is also reported. A method has been determined to remove the soot impurity from the nanotubes with minimal degradation of the nanotube. Neutron diffraction patterns collected before and after sintering show that the nanotubes have remained in the structure while most of the remaining soot has burnt off. Small angle neutron scattering, in conjunction with transmission electron microscopy, also shows preservation of the carbon nanotubes. Mechanical property testing is in progress and results will be reported. © The Authors