Dispersion control and characterization in multiwalled carbon nanotube and phenylethynyl-terminated imide composites

The inherent multifunctional properties of carbon nanotubes provide an opportunity to create novel composites, but their dispersion into a polymer matrix is challenging due to nanotube dimensions, interparticle forces, and poor interaction with the polymer. In this study, we used melt mixing to disperse multiwalled carbon nanotubes (MWNTs) in a polyimide resin under various process conditions to understand the efficacy of the process and the energy required to achieve dispersion and distribution. Through controlled variation of process conditions, we achieved various degrees of nanotube dispersion and distribution. The different dispersion and distribution states were observed by microscopy and correlated with the magnitude of the changes seen in the glass transition temperature and viscosity when compared to the neat resin. The results of these studies will be used to assess the compatibility of nanocomposite resins with composite fabrication methods and predict appropriate processing conditions for producing multiscale composites.