Oil-resistant, anticorrosive and electrostatic-dissipating polyurea coating derived from fluorinated multiple amine

Abstract

As critical components of national energy infrastructure, crude oil storage tanks are prone to corrosion, and pose significant risks of ignition from static electricity. Herein, to enhance oil resistance and corrosion protection, fluorinated multiple amine was synthesized from ethyl heptafluorobutyrate and tetraethylenepentamine and then incorporated into polyurea coating. The hydrophobic and oleophobic characteristics of fluorocarbon chains and the enhanced crosslinking density contributed by multifunctional amines were both beneficial to improve the oil resistance and anticorrosion ability of polyurea coating. When the mass frction of fluorinated multiple amine reached 3 %, the polyurea coating exhibited exceptional corrosion resistance and oil resistance, achieving |Z|_0.1Hz = 5.5 × 10⁸ Ω·cm² after immersion in 5 wt% NaCl solution for 30 d. After the exposure of the coating to neutral salt spray for 3000 h, there was only minimal corrosion on the substrate. In addition, the coating showed no blistering, and no obvious rust on the substrate after immersion in gasoline for 3000 h at 62 °C. Due to the incorporation of conductive mica powders, the surface resistivity of the polyurea coating reduced to below 10¹¹ Ω, thereby fulfilling the requirements of electrostatic dissipation. The oil-resistant, corrosion-resistant and electrostatic-dissipating polyurea coating developed in this work exhibits considerable application potential in the field of crude oil storage facilities protection.