Good and Bad Elastomers for Stretchable Gold Nanowire Composites

Soft and stretchable electronic materials for wearables and implants can have a demanding set of requirements, including biocompatibility, specific mechanical and electromechanical properties, long-term stability, and good electrode performance. To meet these requirements, we have over the years developed stretchable gold nanowire-based conductors for a variety of applications, such as implantable electrode arrays, organic thermoelectric generators, and organic supercapacitors and batteries. Different types of elastomers can be advantageous for certain applications based on their properties and processing. However, when using different elastomers together with gold nanowires we have noticed huge differences in electromechanical performance of the composites, despite similarities in Young’s modulus of the elastomers. Here I present our investigation into the causes of these major variations by comparing the performance, properties, and behavior of 5 different elastomer systems of similar modulus in combination with gold nanowires. The findings have implications when choosing elastomers for stretchable electronic composites and provide support for the interpretation of variations in electromechanical performance.<br/>http://www.liu.se/soft-electronics