Chiang Mai Journal of Science

Composite plates consisting of woven carbon fiber mats, epoxy resin, and conductive fillers, either pristine multi-walled carbon nanotubes (MWCNTs) or chemical modified MWCNTs, were prepared by hand-lay-up and compression molding processes. The MWCNTs were purified by acetone treatment and then non-covalently functionalized by 2-aminoethanol in the presence of sodium hydroxide. The characterization of chemical modified MWCNTs was carried out by using transmission electron microscopy (TEM), Raman spectrometry, and thermogravimetric analysis (TGA). Amounts of conductive fillers from 0.5-2.0 wt% were included in the epoxy matrix to improve the properties of the composites in the through thickness direction. Base-functionalized purified MWCNTs had a better distribution in the resin than did pristine MWCNTs. Results demonstrate that the dispersion of MWCNTs determined the properties of the composite plates. The optimum composite contained 1.5 wt% of base-functionalized purified MWCNTs in epoxy and had a bulk electrical conductivity of 93 S cm^-1, a tensile strength of 0.65 GPa, a flexural strength of 0.70 GPa, a coefficient of thermal expansion (CTE) of 43.65 x 10^{-6 o}C^-1, a water contact angle of 88.6^o, a corrosion current density of 0.43 µA cm^-2, and a density of 1.592 g cm^-3.