Functionalization effect on physico‐mechanical properties of multi‐walled carbon nanotubes/epoxy composites

Abstract

AbstractFunctionalization of multi‐walled carbon nanotubes (MWCNTs) influences physico‐mechanical properties of MWCNT/epoxy composites. Samples based on epoxy resin (EP) and different weight percentage of MWCNTs (functionalized and non‐functionalized) were prepared. Epoxy/carbon nanotubes were prepared by different mixing methods (ultrasounds and a combination of ultrasounds and mechanical mixing) and better dispersion of carbon nanotubes (CNTs) was observed in the case of combination of these processes. CNTs modified with different functional groups were investigated. It was found that modified nanotubes form bigger agglomerates than unmodified ones. Surfactants were used to lower the surface tension of the liquid, which enabled easier spreading and reducing the interfacial tension. Some surfactants facilitate homogeneous dispersion of nanotubes in the resin through the reduction of resin viscosity.Flammability of epoxy/MWCNTs composites was measured by cone calorimeter. The properties of epoxy/nanotubes composites strongly depend on homogeneous and uniform distribution of CNTs in the epoxy matrix. The microstructure of selected samples with the best CNTs homogeneity in the epoxy matrix was observed using atomic force microscope (AFM) and transmission electron microscope (TEM) techniques. The effect of mixing methods and parameters, as well as the amount and functionalization of CNTs, on mechanical properties (such as hardness, bending strength, tensile strength, and impact resistance) was evaluated. Copyright © 2010 John Wiley & Sons, Ltd.