1. Epoxy/PANI–CSA nanocomposite coating which has been synthesized
through one-pot procedure can effectively protect
steel rebars during long term immersion in chloride-laden environment.
Also, based on electrochemical measurements, selfcompacting
concrete (SCC) is more appropriate in order to
reduce the corrosion rate of the reinforcements.
2. The open circuit potential of NC-EP and SCC-EP samples become
nearly stable after 150 days from immersion. The measured values
are ca. 260 and 300 mV/SCE for NC-EP and SCC-EP samples,
respectively. According to ASTM C876-09 standard, there
is a possibility lower than 10% for occurrence of corrosion. Also,
the main reason of an intense decrement in corrosion potential
of bare and epoxy-coated rebars is considered to be electrolyte
penetration into concrete and then epoxy matrix.
3. Long term impedance measurements up to 1 year reveal that
the rebars coated with epoxy/PANI–CSA nanocomposite present
good corrosion resistance in chloride-laden concrete environment.
Presence of a protective passive layer on the steel surface
is proved by analyzing quantitatively the EIS results.
4. Formation of expansive corrosion products on steel rebar surface
severely decreases the ultimate bond strength between
rebar and concrete after 1 year immersion. Good corrosion
resistance of NC-EP and SCC-EP samples gives rise to a remarkable
decrease in reduction ratio of bond strength in comparison
with other samples after long term exposure to 3.5% NaCl
solution.