Robust waterborne superhydrophobic PAI/PTFE/GO@TP anion-release coating with anti-corrosion and anti-scaling performance

Abstract

In oil well field production, fluids cause mechanical damage and chemical corrosion, increasing the demands on the adaptability and durability of superhydrophobic materials. For this purpose, a superhydrophobic/superoleophilic polyamideimide (PAI)/polytetrafluoroethylene (PTFE)/graphene oxide@tourmaline powder (GO@TP) anion-release coating was successfully developed using a combination of hydrothermal synthesis and spraying technology. The crosslinked network formed by the PAI and PTFE endowed the coating with exceptional mechanical durability and adhesion, maintaining a water contact angle of 151.5 ± 1.8° after enduring 800 wear cycles under 125 kPa of pressure. The homogeneous lamellar micro/-nanostructure provided a stable air barrier that shields the coating surface from contact with corrosive substances, ultimately enhancing its anti-corrosion performance. Following a 30-day soaking period, the coating demonstrated an impressive impedance modulus at low frequency, |Z|_0.01 Hz value of 10¹¹ Ω cm². The slow release of hydroxyl anions from the tourmaline powder electrically neutralized, cations in water to form soluble salts, preventing the nucleation of the scale. The oil layer on the PAI/PTFE/GO@TP coating surface synergistically reduced water scale adhesion, resulting in only 0.23 mg/cm² of scaling after 7 days. Moreover, the internal migration and surface arrangement of functional groups significantly improved the chemical stability and weather resistance of the coating. This study presented a feasible approach to expand the functional application of superhydrophobic coatings for anti-scaling and anti-corrosion.