The Effect of Multiwalled Carbon Nano Tubes on Cure Kinetics of Epoxy Resin

The effects of incorporation of multiwall carbon nano tubes (MWNTs) on the cure reaction of a diglycidyl ether of bisphenol-A (DGEBA) and triethylene tetramine (TETA) as a curing agent have been studied with an isothermal differential scanning calorimetry (DSC) technique. Kinetic analysis was performed with the phenomenological model of Kamal and Sourour. Isothermal kinetic parameters were determined and the results show that the kinetically controlled parts of reaction could be expressed well with Kamal and Sourour model while end of curing reaction is diffusionally controlled. Activation energies and kinetic parameters are determined by fitting experimental data for MWNTs/epoxy Nano composites, the initial reaction rate increases and the time required for the maximum rate decreases with increase in MWNTs contents, because of the acceleration effect of MWNTs. The initial rates of MWNTS/Epoxy Nano composites were found to be comparatively higher than that of neat Epoxy at all curing temperatures, whereas the time required to the maximum reaction rate of the Nano composites decreased with increasing MWNTs content, suggesting that MWNTs have an acceleration effect on the Epoxy cure reaction. Compared with the neat DGEBA/TETA Epoxy, the MWNTs/Epoxy Nano composites exhibited lower activation energies for k1, and E1 and decreased with increasing MWNTs. E2 for The MWNTs/Epoxy Nano composites remained the same as that of the neat Epoxy. The further reaction kinetic analysis indicates that the Kamal model can well fit the reaction rate at the kinetic controlled stage which is about 60 % conversion and rest of the reaction is diffusion ally controlled