Chemical Degradation of Epoxy-Polyamide Primer by Electrochemical Impedance Spectroscopy

Table 2

Equivalent circuit parameters of EPZ primer-coated steel in 5% NaCl.

Exposure duration (^*hour/days)	𝑅po (10^7, ohms)	𝑅𝑡 (10^6, ohms)	𝐶𝑐 (10^-9, Faraday)	𝐶dl (10^-7, Faraday)	𝑅𝑡/𝑅po	𝑇𝑚/𝑇𝑓
^*1	5.6	5.26	8.50	1.096	0.094	1.21
1	2.65	3.12	8.00	1.855	0.118	2.73
5	2.14	1.92	7.10	3.016	0.089	3.81
10	0.05	0.63	7.50	9.176	1.260	144.53
15	0.204	1.35	7.60	4.289	0.662	36.19
25	0.152	0.098	7.93	98.27	0.064	80.25
30	0.082	0.062	9.00	936.90	0.076	830.00
55	0.027	0.038	35.02	542.34	0.141	219.25
80	0.0033	0.023	40.12	257.30	0.697	455.23
100	0.0003	0.0058	43.00	996.50	1.933	4446.15