Carbon nanotubes obtained along variations in chemical vapor deposition process for improvement in mechanical properties of an epoxy composite

Carbon nanotubes were produced via chemical vapor deposition using ferrocene as catalyst, benzene as carbon source and argon as carrier gas. Samples were synthesized at 800, 850 and 900 °C, carrier gas flow of 50, 80 and 110 ml/min and reaction time of 1 h. The morphology and average microstructure were analyzed by scanning electron microscopy and X-ray powder diffraction. The Scherrer's equations were used to estimate the average number of walls in the carbon nanotubes. It was observed that the flow of carrier gas modifies the number of the tube walls as follows: for 50 ml/min (40-42 walls), for 80 ml/min (33-39 walls) and for 110 ml/min (30-34 walls). Additionally, was analyzed the effect on the micro-hardness as a result of the incorporation of carbon nanotubes into an epoxy resin. Mechanical tests showed an increase up to 30% in the microhardness with the incorporation of 3 wt% of nanotubes.