EPOXY COMPOSITES WITH CARBON NANOTUBES

Abstract

In the work viscosity, curing process of epoxy resins, electrical conductivity and mechanical strength of epoxy composites with carbon nanotubes were investigated. As a component was used Epidian 6 epoxy resin cured with 1-buthylimidazole by anionic polymerization. Compositions with nanofillers were prepared by sonification of multiwall carbon nanotubes (BAYTUBES 150 P and BAYTUBES 150 HP) in epoxy resin without any solvent. The morphology of prepared nanocomposites was examined by using SEM. Scanning electron microscopy confirms good dispersion of CNTs, but the presence of agglomerates is also identified. Viscosity of compositions with two kind of carbon nanotubes was established by means of ARES rheometer. Curing process with ARES rheometer and DSC was investigated. Bending strengths and electrical conductivity were performed on composites made of an epoxy resin loaded with 0.1, 0.2, 0.5, 1 and 2 wt.% both types of MWNTs. The incorporation of MWCNT to epoxy resin results in a sharp insulator-to- conductor transition with a percolation threshold (φc) as low as 0.5 wt.% for Baytubes 150 HP and 1.0 wt.% for Baytubes 150 P. An electrical conductivity of 10 -4 S/cm was achieved for 0.5 wt. % of MWCNT 150 HP. The low percolation threshold for each MWCNTs and relatively high electrical conductivity are attributed to the high aspect ratio, large surface area and uniform dispersion of the carbon nanotubes in epoxy matrix.