Leucoemeraldine-polyaniline/PVP composite humidity sensor

Over the years, the smart fabric technology has gained large popularity among researchers for its numerous possible applications. An example would be integrated gas sensors, which could provide real-time information of the environment, among other benefits. While metal oxides are heavily researched on for their sensitivities to different gases, they may not be the ideal material to embed onto fabric due to their rigid structure and poor conformability. On the other hand, polymer composites are more flexible and stretchable however, while being less conductive, thus making them less sensitive to gases. In this project, electrospun Leucoemeraldine Base Polyaniline (LEB-PANI) in Polyvinylpyrrolidone (PVP) matrix was used to study its response to Nitrogen Dioxide with 60% relative humidity. The electrospinning parameters, which includes the concentration, potential difference between the collector and needle, as well as flow rate of deposition, were first optimised by studying the morphology of the nanofibers. Once optimised, the LEB-PANI/PVP nanofibers were stored in a gas chamber and exposed to different humidity levels and its response was recorded. Lastly, it is exposed to humidity of 40% to 60%, and NO2 gas concentration of 50ppm to 250ppm in a gas chamber to study its sensitivity. Results showed that LEB-PANI/PVP has good initial response to NO2 gas but poor recovery when the NO2 was flushed out. This flexible polymer composite gas sensor is more conformable as compared to metal oxides, thus a more compatible partner for smart fabric as a gas sensor.Bachelor of Engineering (Mechanical Engineering