Multifunctional conductive polymers with -C=N- conjugated system and functional groups were prepared by polycondensation of carbamide at high temperature under elevated pressure. The corresponding molecular structures of these polycondensation of carbamide products (PCA) were proposed according to the analysis of elemental analysis, FT-IR spectra, UV-Visible absorption spectra and X-ray photoelectron spectroscopy. The morphology of the obtained products can be tuned by controlling the synthesis conditions such as temperature, pressure and catalyst used in the synthesis process. X-ray diffraction (XRD) patterns confirmed the existence of relatively ordered crystal structures for these polymers. Corrosion protection performance of as-prepared coatings with PCAs was investigated based on NaCl solution immersion test. The results indicated that PCA-2 nano-particles can improve the protection performance for metals by increasing the adhesion strength of the epoxy coatings and acting as crosslinldng points to form a dense film. (C) 2016 Elsevier B.V. All rights reserved.