Lately I performed a series of analysis on a novel hybrid silane/epoxy coatings in a NaCl 3.5% solution and found "unusual behaviour" (or at least for me that I'm a beginner). After 44 days I can see an "usual" behaviour but before of that I find negative capacitance at high frequencies.

The instrument was checked and it seems to have no problem (it performs "normal" on other coatings). The thickness of the layer is 100 micron. The coatings works very good (no exfoliation, no sign of damage) I will be very glad to hear your ideas on the topic.