특수한 기능을 가지는 나노 구조가 올라간 신축성 멤브레인 제작

Abstract

Due to the explosive development and industrialization of medical technology, mankind has recently faced many problems. In developed countries, mankind can lead an affluent life, but as the average life expectancy increases, interest in health is gradually increasing. On the other hand, regions such as Africa and South America face increasing global warming, chronic viruses, and water scarcity. Various technologies have been studied, but most of them are studies to maximize performance, not actual use, and stability and effectiveness are insufficient to connect with actual applications. However, with the recent increase in research on stretchable materials, research on the manufacture of materials and structures is being actively conducted, and in some cases, it is more stable and durable than previous studies. New functionality and high efficiency can also be achieved by using stretchable materials. In particular, strain sensors used in wearable devices have different tensile ranges and sensitivity depending on their use, and many studies on this are far from commercialization, maximizing sensitivity or tensile range. In the first part of this paper, we report strain sensors with a wide tensile range and high sensitivity. This sensor was designed through surface crack structure analysis using polyurethane (PU), a stretchable material, and platinum (Pt), a conductive material. The built sensors can reliably measure signals at low and high tension of 5% or less and 50% or more, and the resistance signal has a signal delay time of 10 ms or less even if 50% is applied, and also has excellent linearity of R2 = 0.9814. Using the manufactured sensor, it was used to track the 3D joystick position in a wide tensile range and measure the end tension of the vitreoretinal force that requires high sensitivity. Membrane distillation (MD) is a technology that attracts attention to solve water shortages, which is an important issue in the world. In the second part of the paper, we report a membrane with a special superhydrophobic layer on the stretchable material, attempting to solve problems in the existing RO using MD. The membrane was manufactured through a simple manufacturing process, including electrospinning and electrospraying, and the membrane was naturally porous. In addition, a special structure in which microsphere and nanowire were combined was created by intentionally adding a high humidity environment during the electrospraying process, which was used for direct contact membrane distillation (DCMD). The thickness of the superhydrophobic layer optimized in accordance with each electrospray time was found, and at this time, diffusive flux achieved a maximum of 47 L/m2h for 10 hours of operation. This is a high value even compared to RO, and the applied MD system was verified through simulation. In addition, we theoretically and experimentally demonstrate that performance is maintained up to 55% compared to RO, which is less than 10% efficient at 10 wt% in high-salt seawater. This has great advantages in high concentration seawater desalination as well as conventional low-concentration seawater desalination in MD operation and will contribute greatly to future commercialization.