(338m) The Impact of Small Molecular Dopants on a PANI-Pampsa Polymer Complex System

The utilization of wearable strain sensors has been advancing in modern life owing to their potential to detect, respond, and interpret mechanical deformations from corresponding electrical signals, that are measured in electrical resistance units. Polymeric piezoresistive sensors, which possess significant flexibility and wearable characteristics, have found widespread application in areas such as biosensing, human-motion tracking and recognition, e-skin, and human-machine interaction. Traditional strain sensors, based on metallic and semiconducting material exhibit low sensitivity and inadequate resistance response upon straining endow the need for developing compliant, elastic, stretchable, and self-healable sensors. In this work, the polymer complex is composed of a templating poly(2-acrylamido-2-methyl-1-propanesulfonic acid), polyaniline, and a small molecule dopant, originally phytic acid. By substituting the small molecule dopant with other small molecule acids, the impact the various dopants have on the strain sensor’s conductivity, mechanical properties, and piezoresistive sensitivity can be studied. In general, small molecule dopants that enhance conductivity tend to reduce the stretchability and mechanical stability of the strain sensor, as the more acidic dopants can protonate and promote ion transportation within the sensor. It has been shown that the functional groups with increased hydrogen bonding tend to increase mechanical properties. By increasing our understanding of the impact these various dopants have on the properties of the strain sensor, the sensor can be tailored to specific applications, allowing for increased sensitivity when needed or increased stretchability when required. This will allow for the development of novel materials as we seek to manufacture better stretchable electronics.