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The Electric Impedance Spectroscopy (EIS) was used to evaluate resistivity, capacitance and relaxation processes of a cured epoxy system with different molar composition of 1,4-butanediol diglycidyl ether (EP), succinic anhydride (SA) and triethylamine (TEA) as initiator. The measurements were done over range frequencies between 10 −1 and 10 5 Hz. The systematic change of the molar fraction composition affected the resistivity and capacitance changes indicating gelation critical compositions according to the Flory’s aggregation theory. The complex electric functions, dielectric constant e • , electric modulus M • , impedance Z • , admittance Y • and the loss factor tan δ were utilized in order to investigate the relaxation processes. Relaxation peaks were observed for different molar fraction composition only in the imaginary impedance, the electric modulus and the tan δ as frequency functions. The relaxation frequencies obtained by Z ″, M ″ and tan δ evaluation are distinct and have been discussed in terms of resin components molar fraction dependence. |
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