Endowing versatility and superamphiphobicity to composite coating via a bioinspired strategy

The strong adhesion by crude oil and the deposition of wax in petrochemical pipeline systems are notorious problems, which seriously threaten the safety and economic production of the petroleum industry. Superamphiphobic coatings that repel water/oil offer exciting opportunities to solve these problems, but there are formidable challenges in developing elaborate structures facilely. Herein, a springtail-inspired and multifunctional superamphiphobic coating (OCA = 152.1 +/- 0.4 degrees, OSA = 8.2 +/- 0.8 degrees) was prepared by a straightforward spraying technique. To emulate the cuticular characteristics of the springtail, the micro-/nano-hierarchical fillers prepared by loading silica nanoparticles on the surface of hollow glass microspheres and then chemical modification (F-HGM@SiO2) and the fluorinated nano-silica (F-SiO2) were simultaneously introduced into polyvinylidene fluoride (PVDF) to construct a micro-/nano-/nano-hierarchical structure on the PVDF/F-HGM@SiO2/ F-SiO2 surface. Hence, a durable air layer was formed due to the suitable rough structure in conjunction with low-surface-energy groups, which endows the coating with outstanding crude-oil-repellency. Moreover, based on the self-designed test device, the coating showed an excellent anti-waxing deposition ratio (R = 82.76 %). Significantly, on the basis of the morphologies, wettability, and anti-waxing performance of the coatings, the main liquid-wettability, and anti-waxing mechanisms were illustrated, which revealed the inseparable relationship between them. The durability of the coating was investigated through mechanical/chemical damage tests (the OCA and OSA were kept above 140 degrees and below 30 degrees, respectively). Therefore, this bioinspired superamphiphobic coating is expected to open up new avenues for the design and fabrication of anti-waxing coating, which present enormous application value in oily/corrosive environments.

Automated summary

The strong adhesion by crude oil and the deposition of wax in petrochemical pipeline systems are serious problems. A superamphiphobic coating inspired by the springtail was prepared and showed excellent crude-oil-repellency. The coating also exhibited a high anti-waxing deposition ratio. The study provides insights into the liquid-wettability and anti-waxing mechanisms, and the coating has potential applications in oily/corrosive environments.