가혹한 조건하에서 윤활유가 함침된 양극 산화 알루미늄 (AAO-LIS)의 지속적인 미끄럼 특성에 관한 연구

Abstract

The wettability of surfaces plays a crucial role in determining their applications, and slippery surfaces have been utilized in various fields. Especially, lubricant-infused surface (LIS), which is fabricated by infusing lubricants into the surface structure, has been extensively researched over the past decade. One significant challenge faced by LIS is the tendency to lose its infused lubricant over time when exposed to harsh conditions, resulting in a subsequent decline in its slippery properties. Therefore, there is a strong need to improve the lubrication durability. In this study, two strategies are employed to improve the lubrication durability against centrifugal forces and high-speed shear flows. One strategy is using re-entrant shaped nanocavities, and the other is modifying the surface through the grafting of PDMS brush. For Anodic aluminum oxide (AAO) is employed to fabricate the re-entrant shaped nanocavities, and the lubrication durability is improved when the cavities possess a smaller diameter. Furthermore, the shape of these nanocavities significantly improves durability compared to nanocavities with a constant diameter. The grafting of PDMS brush is essential for enhancing the durability, and an increase in the length of the PDMS brush results in a corresponding improvement in the durability. The fabricated AAO-based LIS (AAO-LIS) exhibits remarkable durability of slipperiness, maintaining it for 50 min under a high-speed water flow of 12 m/s. However, LISs that do not have the nanostructure or re-entrant configuration lose their slipperiness within 10 min under the same conditions. Also, the AAO- LIS maintains its superior slipperiness more than a few days when exposed to seawater. Furthermore, the AAO-LIS maintains a certain drag reduction performance even after losing its superior slipperiness, demonstrating its strong potential for practical applications across various industrial fields