Processing and characterization of epoxy nanocomposites with MWCNT'S/CNF's using thinky and 3-roll shear mixing techniques

Abstract

In this work, thinky mixing method was used to disperse multi-walled carbon nanotubes (MWCNT's) and carbon nanofibers (CNF's) in SC-1 epoxy either in isolation or in combination with 3-roll shear mixing. To achieve better dispersion, MWCNT mixing with SC-1 resin directly or pre-mixed with a solvent and then mixed with SC-1 resin after evaporating the solvent. Dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), flexural tests, electrical conductivity tests and micrographic analysis were performed on neat, 0.2 and 0.4wt% MWCNT/CNF infused SC-1 epoxy to observe the loading effect on thermo-mechanical properties of composites. DMA results indicated improvement on storage modulus and glass transition temperature, Tg, while flexural results exhibited enhanced flexural strength and modulus with up to 0.4wt% MWCNT/CNF infused epoxy resin over neat. TGA results revealed improved residue content but almost constant decomposition temperature for nanophased resin compared to neat. However, these enhancements were observed only up to 0.2 wt. % loading after which the properties were seen to either reduce or not significantly improve. These results indicate that the methods used for dispersion is suitable for low weight percent loading only.