Improved anti-corrosion and self-healing performance of epoxy coatings reinforced by chitosan encapsulated mesoporous silica nanocontainers

In this work, corrosion inhibitor of 1H-Benzotriazole (BTA) was loaded into hollow mesoporous silica nanocontainers (HMSNs-BTA). Then, chitosan (CS) was coated on the surface of the HMSNs (HMSNs-BTA@CS) to realize pH-controlled release of BTA. The prepared HMSN-BTA@CS was used to enhance the corrosion resistance of epoxy coating. The results show that the pH-controlled release of BTA endows the coating with self-healing ability. After 60 days immersion in salt solution, the low-frequency impedance modulus of HMSNs-BTA@CS reinforced epoxy coating still reaches 3.74 × 108 Ω cm2. This is caused by the healing effect of BTA and the good dispersion of the nanofillers in epoxy coating.