The electrical response of carbon nanotube-based thin film sensors subjected to mechanical and environmental effects

Fiber-reinforced polymer composites are a popular alternative to traditional metal alloys. However, their internally occurring damage modes call for strategies to monitor these structures. Multi-walled carbon nanotube-based polyelectrolyte thin films were manufactured using a layer-by-layer deposition methodology. The thin films were applied directly to the surface of glass fiber-reinforced polymer composites, with the purpose of structural monitoring. This work focuses on characterizing the sensitivity of the electrical properties of the film using time- and frequency-domain methods under applied quasi-static and dynamic mechanical loading. In addition, environmental effects such as those of temperature and humidity are varied to characterize the sensitivity of the electrical properties to these phenomena.