Effects of single-walled carbon nanotube incorporation on the cure reaction of epoxy resin and its detection by Raman spectroscopy

The effects of the incorporation of single-walled carbon nanotubes (SWNTs) on the cure reaction of a diglycidyl ether of bisphenol A-based (DGEBA) epoxy resin is investigated by thermal analysis and Raman spectroscopy. The results of the investigation show that SWNTs act as a strong catalyst. A shift of the exothermic reaction peak to lower temperatures is in fact observed in the presence of SWNTs. Moreover, these effects are already noticeable at the lowest SWNT content investigated (5%) with slightly further effects at higher concentrations, suggesting a saturation of the catalysing action at the higher concentrations studied (10%). The thermal stability of cured DGEBA and DGEBA/SWNT composites was examined by thermogravimetry, showing a faster thermal degradation for DGEBA-SWNT composites. Raman spectroscopy was successfully applied to demonstrate that the changes observed in the cure reaction of the composites lead to a different residual strain on the SWNT bundles, following a different intercalation of the epoxy matrix. (C) 2002 Elsevier Science B.V. All rights reserved.