Effect of Nickel Doping on the Cure Kinetics of Epoxy/Fe3O4 Nanocomposites

Abstract

This short communication aims to evaluate the cure kinetics of epoxy/NixFe3−xO4 nanocomposites. Differential scanning calorimetry (DSC) provided support for cure kinetics analysis based on the variation of activation energy (Eα) as a function of the extent of crosslinking reaction, α. The average values of Eα calculated based on Kissinger and Friedman methods were 59.22 and 57.35 kJ/mol for the neat epoxy, 43.37 and 48.74 kJ/mol for the epoxy/Fe3O4, and eventually 50.48 and 49.19 kJ/mol for the epoxy/NixFe3−xO4 nanocomposites. The partial replacement of Fe2+ ion sites in the Fe3O4 crystal lattice by the Ni2+ ions changed to some content the cure kinetic profile because of the fact that a lower level of energy was needed for curing by incorporation of NixFe3−xO4 into the epoxy matrix. The rate of reaction calculated theoretically adequately fitted with experimental profiles obtained in DSC experiments.

Cure Kinetics of Samarium-Doped Fe3O4/Epoxy Nanocomposites

“…A more accurate Malek method was applied to determine the cross-linking reaction model through the shape and maximum points of y(α) and z(α) Malek master plots (Equations ( 6) and ( 7)) [59]. As can be observed in Figure 10 and Table 2, α m = Max (y(α)) is lower than α p = Max (z(α)) and αp ∞ (the conversion at the maximum point of DSC curves) is smaller than 0.632, which revealed that the two-parameter autocatalytic model could be used for both EP and EP/Sm-Fe 3 O 4 nanocomposite [60,61].…”

“…(Equations ( 6) and ( 7)) [59]. As can be observed in Figure 10 and Table 2, αm = Max (y(α)) is lower than αp = Max (z(α)) and αp ∞ (the conversion at the maximum point of DSC curves) is smaller than 0.632, which revealed that the two-parameter autocatalytic model could be used for both EP and EP/Sm-Fe3O4 nanocomposite [60,61].…”

Nonisothermal cure behavior and kinetics of cerium‐doped Fe3O4/epoxy nanocomposites

“…[ [25][26][27] Zn-Fe 3 O 4 Zn doping OH and Zn 2+ Zn 2+ cations play the role of Lewis acid and facilitate the oxirane ring opening. They selectively catalyze the autocatalytic reaction.…”