Preparation, controlled release, and anticorrosion behavior of benzotriazole-loaded modified halloysite nanotubes

摘要

Loading capacity and controlled release are two important features of smart corrosion inhibitor nanocontainers. In this presentation, we highlight recent findings of our group in modifying the surface of halloysite nanotubes (HNTs) and developing a tube end stopper to increase loading capacity and control benzotriazole (BTA) release. To increase BTA loading capacity, we employed a combination of two approaches: heat treatment and Zn 2+ cation preadsorption, a method previously published by our team.[1] Besides, to control the release of BTA, two types of tube end stoppers have been investigated, including a complex between zinc ion and BTA (Zn -BTA) and a complex between ferric ion and tannic acid (Fe -TA). The results showed that surface treatment and modification increased the BTA loading capacity of modified HNT to 15.5 wt.%, much higher than the 4.57 wt.% of the original HNT. Moreover, the BTA release process was also controlled by either the Zn -BTA or Fe -TA stoppers. Both stoppers exhibited slow BTA release rates from the nanocontainers in neutral environments and gradually increased as pH decreased. As a result, the smart corrosion inhibitor nanocontainer systems Zn -BTA@BTA/modified-HNT and Fe -TA@modified-HNT not only show excellent corrosion inhibition effects but also exhibit active corrosion inhibition properties when applied as additiv es in epoxy coatings on carbon steel, as demonstrated by electrochemical measurements and salt spray testing.