Investigation of conductive printed thermoplastic polyurethane nanofibers to detect the clogging of air filters

Recently, air pollution attracted many worries because of its high number of deaths per year. To solve the problem, the industries are trying to fabricate the giant air filtration system for public areas. However, the clogging of air filters should be detected in real-time to change or clean them. E-textile is a very fascinating field, which is often used in medical, safety, military and clogging detection applications. These components are integrated into soft textile materials according to their usage requirements. One of the most attractive textile structures is the nanofibers due to their advantageous properties such as porosity, lightweight, and high surface area. To have conductive nanofiber-based membrane sensors, two in situ electrical conductivity principles using conductive particles and surface conductivity, such as immersion and printing methods are recommended. In this research, the thermoplastic polyurethane (TPU) nanofibers' membranes are produced using an electrospinning system and the carbon ink was printed on the surface of nanofibers to apply in textile sensors applications. SEM images showed the uniform structure of the nanofibers and the porosity of the system even after printing. The electromechanical properties of printed membranes demonstrated the change of electrical resistance under stretch. Conclusively, these conductive membranes could be employed as strain sensors to detect the small changes in the output airflow indicated the possible clogging of air filters.