Multifunctional Ultrastretchable Printed Soft Electronic Devices for Wearable Applications

Multifunctionality is a major development trend in flexible stretchable wearable electronics, requiring integration of electrical conductivity, sensing performance, and heating management on a portable electronic device. Herein, the silver fractal dendrites (Ag FDs) conductive ink is formulated and deposited into the polystyrene-block-polyisoprene-block-polystyrene (SIS) thin films by a simple and cost-effective transfer-printing method for preparing the patterned multifunctional wearable electronics (MWEs). The MWEs based on Ag FDs ink-38 wt% exhibit high electrical conductivity (4.86 x 10(5) S m(-1)), excellent sensing property (highly stretchability of 500% with a maximum gauge factor (GF) of 659.5), low-voltage driving Joule heating performance (heated to 52.3 degrees C at 1 V), and good mechanical stability. As strain sensors, the MWEs have been successfully used to monitor the bending motion of the six major joints in the human body. As Joule heaters, the MWEs have been successfully used for thermochromism and hyperthermia. The developed MWEs prepared by a simple and low-cost transfer-printing possess highly promising application for next-generation multifunctional and smart wearable electronics.