A Waterborne Epoxy Composite Coating with Smart Corrosion Resistance Based on 2-Phenylbenzimidazole-5-sulfonic Acid/Layered Double Hydroxide Composite

Abstract

In this study, ZnAl-layered double hydroxide (ZnAl-LDH) was functionalized with 2-Phenylbenzimidazole-5-sulfonic acid (PBSA) to prepare ZnAl-PBSA-LDH using a simple one-step method. The electrochemical impedance spectroscopy (EIS) result of the solution phase demonstrated excellent corrosion inhibition performance of ZnAl-PBSA-LDH. Subsequently, 0.6 wt.% ZnAl-PBSA-LDH with shielding effects and active inhibition was incorporated into the water-based epoxy (WEP) for preparing the high-performance anti-corrosion coating (6-ZPL/WEP). The EIS test illustrated that the 6-ZPL/WEP coating maintained a high low-frequency impedance modulus (|Z0.01 Hz|) after 30 days of immersion, which is nearly two orders of magnitude higher compared to that of the blank coating. These results demonstrated that ZnAl-PBSA-LDH could efficiently improve the corrosion resistance of the WEP coating. Therefore, this study introduces new insights into the use of layered double hydroxides (LDHs) in the domain of anti-corrosion.

Self-Oriented Functionalized MXene with Excellent Antioxidant Properties for Enhancing Anticorrosion Properties of Waterborne Epoxy Resin

“…As depicted in Figure a, the WEC displayed a smooth cross section with several deep holes (red circle). These holes serve as pathways for corrosive media to permeate the WEC, which leads to the corrosion of protected metal . In Figure b, the cross section of MX/WEC appeared rougher with shallower holes compared with those of WEC (Figure b).…”

“…These holes serve as pathways for corrosive media to permeate the WEC, which leads to the corrosion of protected metal. 34 In Figure 5b, the cross section of MX/WEC appeared rougher with shallower holes compared with those of WEC (Figure 5b). However, the presence of uneven jagged cracks in MX/WEC suggested poor compatibility between MXene and WEC.…”

Anti-corrosion applications of 2D transition metal based layered materials

“…Therefore, LDHs have great application prospects in conversion coatings or as nanofillers for polymer coatings. 125…”

MXene‐CeO2@PDA Synergistically Enhanced Anticorrosion of Waterborne Epoxy Coating

“…[4,5] However, micropores/microcracks easily emerge in WEP coating due to water evaporation during the curing process, allowing the penetration and diffusion of corrosive media within the coating and resulting in the degeneration of corrosion resistance. [6,7] It was reported that the incorporation of two-dimensional nanosheet fillers (such as BN, [7] GO, [8,9] LDH, [10] etc.) could effectively reduce/avoid micropores/microcracks of the filler/WEP composite coatings and enhance the corrosion resistance.…”