Investigation of optical properties and glass transition temperature of nano-epoxy matrix

In this research work, nanocomposites were synthesized by addition of fractions (0.0, 0.02, 0.04 and 0.06) of multi-wall carbon nanotubes (MWCNTs) to epoxy resin to investigate the optical properties and glass transition temperature. Optical measurement shows that epoxy matrix films have high absorption at the different MWCNTs fractions (0.0, 0.02, 0.04 and 0.06). The optical energy gaps for allowed direct transition were evaluated and found to decrease with increasing film fractions, precisely, from 2.85 to 1.32 eV when fractions increased from 0.0 to 0.06 of the matrix weights that indicated strong shifts at 435–935 nm with increasing fraction. The values of the absorption coefficient and extinction coefficient increased with fractions of MWCNTs while the refractive index and the real part of dielectric constant decreased with the fractions of MWCNTs. Also, the glass transition temperature was investigated and was found to increase with increasing fraction of carbon nanotube in the matrix.