Highly Conductive, Stretchable Polymer

Stanford researchers have developed a highly conductive, stretchable polymer that is durable enough for wearable electronics. To improve flexibility they doped poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)with ionic liquid plasticizer. The plasticizer provides a fiber-like morphology, improves connectivity and conductively via the doping anions. The transparent doped PEDOT:PSS is stretchable to twice its initial length, and maintains conductivity on the order of 10² to 10³ S/cm. The water based dispersion can be directly printed onto substrates, making it an excellent electrode or interconnect for wearable electronic devices.

Figure 1 Photographs illustrating the minimal change in LED brightness as the device is stretched under twisting and poked with a sharp object, respectively.

Stage of Research
Researchers continue to test different ionic liquids and processing methods to optimize properties.