POLYPYRROLE-BASED TEXTILE SENSORS FOR PERSONAL PROTECTION

In this study, we demonstrated the potential of flexible PPy thin-film coated textiles as material for manufacturing sensors suitable for integration into garments to produce functional e-textiles. We presented a simple synthesis that generates thin PPy layers on PA66 fabric. The high flexibility of the sensing element allows for its integration into garments. The sensor elements are multifunctional and can indicate temperature and be used as gas sensors for the detection of corrosive gases such as HCl or NH₃. In the presence of 20–100 ppm gaseous HCl, a proportional reduction in resistance of the sensing element is observed, while 100–400 ppm NH₃ causes a concentration-dependent increase in resistance. The direction of the resistance change in the sensor element allows for distinguishing between gaseous HCl and NH₃. The change in resistance also allows a quantification of the respective gas concentration. When the PPy sensor element is covered by an impermeable thin layer, the sensor indicates temperature only. By combining HCl and NH₃ gas-sensitive PPy sensor elements with a fully covered PPy sensor, the combination of devices allows for indicating both corrosive gases and temperature. The results of the temperature sensor can be used for temperature correction of the gas sensor signal. The sensors are of high interest to be integrated into personal protection cloth for workers in various industries to be alerted in case of danger. The simple and cheap manufacturing process of the sensor elements will allow for their design as disposable devices that can be replaced easily after an alert. Future work will address an improvement of the adhesion of the PPy layer, e.g., by activation of the PA66 fabric surface by complexation, in situ polymer grafting, and plasma treatment to enhance stability against wash ageing and mechanical abrasion. The aspect of functional ageing of the coated fabrics and the durable contacting of the sensor will also be addressed in future studies.

Publication:

Gleissner C, Mayer P, Bechtold T, Pham T (2024) Multifunctional Polypyrrole-Based Textile Sensors for Integration into Personal Protection Equipment. Sensors 24:1387. https://doi.org/10.3390/s24051387