ZnPA@ZIF-8 nanoparticles: Synthesis, sustained release properties and anticorrosion performance

Abstract

Zeolitic imidazolate framework-8 (ZIF-8) has attracted extensive attention in many different fields because of its advantages such as small size, ordered channels, adjustable structure, large specific surface area and simple synthesis. In this paper, zinc phytate (ZnPA) as single metal source and 2-methylimidazole (2-MI) as ligand were creatively used to synthesize ZnPA@ZIF-8 nanoparticles by a one-step process. ZnPA and 2-MI are both green and environmentally friendly corrosion inhibitors. In addition, Zn2+ in ZnPA can coordinate with 2-MI to produce ZIF-8, leading to anchor and encapsulate of ZnPA on ZIF-8. Thus, the design of ZnPA@ZIF-8 nanoparticles is of significance for anticorrosion of metal. Furthermore, the introduce of ZnPA@ZIF-8 nanoparticles into waterborne polyacrylate (WPA) was reported for the first time and an in depth study of anticorrosion performance and mechanism of WPA/ZnPA@ZIF-8 composite coating were conducted. The results showed that ZnPA@ZIF-8 nanoparticles were triumphantly fabricated. Moreover, ZnPA@ZIF-8 nanoparticles could be dissolved and successfully released the ZnPA under the stimulation of salt solution. WPA/ZnPA@ZIF-8 composite coating exhibited prominent corrosion resistance, compared with WPA coating, WPA/ZnPA composite coating and WPA/ZIF-8 composite coating. The impedance modulus at 10−2 Hz of WPA/ZnPA@ZIF-8 composite coating was 106.05 Ω∙cm2, which was increased by 2.97 orders of magnitude than pure WPA coating. The above results demonstrated the application potential of ZnPA@ZIF-8 nanoparticles in metal anticorrosion.