Mechanical and viscoelastic study of functionalized MWCNTs/epoxy/Kevlar composites

Nanomaterials‐strengthened diglycidyl ether of bisphenol A (DGEBA) epoxy resin and aramid fiber composites were investigated for 0.16 wt% and 0.32 wt% of industrial and COOH‐functionalized multiwalled carbon nanotubes (MWCNTs). Epoxy/Kevlar fiber/MWCNT hybrid composites were prepared using a vacuum resin‐infusion molding method (VRIM) based on 0.68 aramid fiber mass fractions. The effects of MWCNTs on the viscoelastic, mechanical, and thermal properties of composites were investigated. The chemical structure of composites was studied using Fourier‐transform infrared spectroscopy. Samples with COOH‐functionalized nanotubes showed a strong impact on thermogravimetric analysis, in contrast to composites having the equivalent amount of industrial grade MWCNTs. The outcomes show that addition of MWCNTs to epoxy has a substantial influence on viscoelastic properties. The viscoelastic and thermal analyses show that storage modulus escalates with the addition of functionalized MWCNTs. Micrographs of MWCNTs‐enriched epoxy and Kevlar/epoxy samples revealed the uniform distribution of COOH‐functionalized MWCNTs in epoxy (as compared to industrial grade MWCNTs), resulting in increased interfacial strength between fiber/matrix. POLYM. COMPOS., 39:E2064–E2073, 2018. © 2017 Society of Plastics Engineers