Dendrimer like mesoporous silica nano container (DMSN) based smart self healing coating for corrosion protection performance

A new generation smart self-healing coating possessing both passive matrix functionality and rapid response to local changes in the environment is of great industrial importance. In the present work, a stimulus responsive smart self -healing anticorrosion coating was developed based on acrylic resin, incorporated with Dendrimer like Mesoporous Silica Nanoparticles (DMSN) loaded inside with 8-hydroxyquinoline inhibitor. FESEM and TEM analysis showed that the dendrimer like mesoporous silica (DMS) nanoparticles synthesized were of spherical and fibrous form with size less than 200 nm. The BET surface area, pore volume and average pore diameter of the nanoparticles were found to be 1322.4 m2 g−1, 1.39 cc/g and 4.2 nm respectively. The corrosion protection performance of the coatings was evaluated via Electrochemical Impedance Spectroscopy (EIS) in 3.5 % NaCl. The acrylic coating with dendrimer like silica nano containers showed improved and long-term corrosion protection than the coating without nano containers. The smart self-healing property of the coating was studied by Scanning Vibrating Electrode Technique (SVET). The SVET showed a smartness activity of DMSN by release of inhibitor triggered by corrosion phenomena in the defect area. Further, to reassert the smartness of the coating, impedance mapping of the surface was carried out at a fixed frequency.