Study on the wetting characteristics and mechanisms of aviation gasoline on surfaces with different structural properties

The surface properties of materials inside aircraft engines are diverse, and the interaction mechanism between them and multi-component aviation gasoline is not yet clear. This study focused on the silicone rubber material used for aircraft pipeline connections. Through methods such as screen printing, laser etching, and low surface tension liquid spraying, surfaces with different structural characteristics such as hydrophobic, superhydrophobic, and superamphiphobic were successfully prepared. Research on 100LL aviation gasoline (surface tension ∼22 mN/m, complex chemical composition) showed that although the silicone rubber surface presented superamphiphobicity (contact angle with hexadecane >150°, rolling angle <10°), the surface with micron-sized pits (pit center width ∼25 µm, length ∼0.4 mm) still showed rapid spreading and wetting of 100LL aviation gasoline (contact angle CA ≈ 0°). The significant capillary effect shortened the wetting diffusion time to <1 s and sharply reduced the evaporation loss time to <7 s. In contrast, spraying a superamphiphobic coating on a flat substrate could effectively weaken the capillary effect, significantly delay the wetting of 100LL aviation gasoline (CA ≈ 67°), and greatly extend its evaporation time to >428 s. This result highlights the key role of micro-nano structure design of material surfaces in the wetting and evaporation kinetics of 100LL aviation gasoline. At the end of the article, based on the experimental content of this study, the intrinsic mechanism of the experimental phenomena was deeply analyzed from the perspectives of surface structure, liquid tension, and microscopic molecular interactions. This research provides an important theoretical basis for optimizing the application performance of aviation gasoline and developing new anti-fuel-wetting surfaces.