Electroactive polyurea bearing oligoaniline pendants: Electrochromic and anticorrosive properties

- A novel polyurea bearing oligoaniline pendants has been designed and synthesized.
- The obtained electroactive polyurea exhibits excellent electrochromic performance.
- The electroactive polyurea shows exciting anticorrosion behaviors for CRS.

In this study, a novel polyurea with oligoaniline pendants was prepared in a single step from readily accessible monomer. Fourier-transform infrared spectra (FTIR), nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) were employed to characterize the molecular structure of the obtained electroactive polyurea (EPU). Its spectroscopic properties and thermal stability were also detected and evaluated. The electrochemical activity of EPU was explored by cyclic voltammetry in 0.5 M H2SO4 confirming a surface controlled process. The spectrochronoamperometry was applied to investigate the electrochromic performance of EPU/ITO electrode, which exhibited good electrochromic properties with high contrast value, moderate switching times, acceptable coloration efficiency and excellent stability. Furthermore, corrosive protection of the EPU coatings on the cold rolled steel (CRS) in 5 wt% NaCl solution were studied by tafel plots analysis and electrochemical impedance spectroscopy. The results indicated that the synthesized EPU is a good candidate for inhibiting the corrosion of CRS in brine medium.