One-step preparation of inhibitor-loaded nanocontainers and their application in self-healing coatings
Zhengyu Jin, Zilong Zhao, Tong Zhao, Hongwei Liu, Hongwei Liu, Hongfang Liu, Hongfang Liu
Abstract
In this work, a novel graphene oxide (GO)/SiO2-based nanocontainer loaded benzotriazole (BTA) was synthesized by a one-step method. The self-healing epoxy resin coating with high corrosion resistance based on GO-SiO2-benzotriazole (GS-BTA) nanocontainers was prepared. Electrochemical impedance spectroscopy (EIS) and wire beam electrode impedance scanning (WBE-EIS) measurements were used to evaluate the long-term anticorrosion and self-healing properties of coatings, respectively. Results indicate that the long-term corrosion resistance of GS-BTA coating is largely improved compared with the pure epoxy coating from EIS results. And the impedance of GS-BTA coating changes little after 48 d of testing. The impedance value at 0.01 Hz for pure EP coating has a fast decrease with time, and the value is 7.7 × 106 Ω cm2 on the 48th day. The impedance values of GS-BTA/EP coating change little with time, and the value increases by three orders of magnitude on the 48th day compared with the EP coating. The impedance distributions of WBE suggest that the GS-BTA coating has a good self-healing ability in the artificial scratch area. The self-healing ability derives from the release of BTA and its adsorption at anodic corrosion sites.