Fabrication, morphology and cure behavior of triethylenetetramine-grafted multiwalled carbon nanotube/epoxy nanocomposites

Abstract

Multiwalled carbon nanotubes (MWCNTs) were first treated by a 3:1 (v/v) mixture of concentrated H2SO4/HNO3, and then triethylenetetramine (TETA) grafting was carried out. X-Ray photoelectron spectroscopy and Raman spectroscopy analyses proved the effectiveness of this kind of chemical functionalization method. The TETA thin layer was formed on the MWCNT surface, which contributes to good dispersion of MWCNTs in epoxy matrix. Cure behaviors of MWCNT/epoxy systems were studied with non-isothermal differential scanning calorimetry. MWCNTs have the retarding effect on the cure reaction owing to their steric hindrance, while TETA functional groups on the MWCNT surface can accelerate the primary amine- epoxide reaction and weaken the inhibition effect on the process of cure. A qualitative analysis of the degree of vitrification in different epoxy systems was performed. The activation energy of the cure reactions was obtained by the Flynn-Wall-Ozawa method. © 2009 The Society of Polymer Science, Japan.