SYNTHESIS AND PROPERTIES OF MWCNT-HAP COMPOSITES VIA SOL-GEL TECHNIQUE

In the present study, bioceramic composites based hydroxyapatite (HAp) reinforced with carbon nanotubes (CNTs) was synthesized via sol-gel technique. The dried gels were individually heated at a rate of ۵°C/min up to ۶۰۰°C for ۲ h in a muffle furnace in order to obtain HAp-MWCNTs mixed powder. Composites were characterized by XRD, FT-IR, SEM, TEM/SAED/EDX and Raman spectroscopy techniques. Results showed the synthesis of HAp particles in the MWCNTs sol which was prepared in advance, leads to an excellent dispersion of MWCNTs in HAp matrix. Apparent average size of crystallites increased by increasing the percentage of MWCNTs. The average crystallite size of samples (at ۶۰۰°C), estimated by Scherrer’s equation was found to be ~۵۰-۶۰ nm and was confirmed by TEM. MWCNTs kept their cylindrical graphitic structure in composites and pinned and fastened HAp by the formation of hooks and bridges.

Keywords:

Ceramic-Matrix composites , Nanostructures , CNT , sol-gel , SEM , TEM.