Investigation of curing kinetics of sodium carboxymethyl cellulose/epoxy resin system by differential scanning calorimetry

Sodium carboxymethyl cellulose (CMC) have been used to disperse carbon nanotubes (CNTs) and have potential applications to make the CNTs/epoxy or CNTs/epoxy/carbon fiber composites. In this paper, the curing kinetics of epoxy resins with and without CMC and cured with 4,4′-diamino diphenyl methane (DDM) hardener was studied by non-isothermal differential scanning calorimetry (DSC). A two-parameter (m, n) autocatalytic model was used to describe the cure kinetics of the epoxy resins. The kinetic parameters were calculated with the Málek method and least square regression (LSR) method, respectively. The curves by Málek method and LSR method both show a good agreement with the experimental data for Epoxy/DDM and CMC/epoxy/DDM systems. The results, based on the two methods, showed that the activation energy was no obvious difference with the addition of CMC, which indicated that the CMC have no effect on the curing reaction without changing the kinetic model.

Comparison of experimental values (symbols) and calculated values (lines). (a) E51/DDM and (b) CMC/E51/DDM.Figure optionsDownload as PowerPoint slideHighlights
► CMC have potential applications in fabrication of CNTs/epoxy composites.
► The influence of CMC on the epoxy resin curing process was investigated.
► CMC can facilitate the curing reaction of epoxy resin.
► Cure reaction could be successfully described with the autocatalytic model.