Naoji Matsuhisa1, Daishi Inoue2, Peter Zalar1,3†, Hanbit Jin1, Yorishige Matsuba1,3, Akira Itoh1,3,Tomoyuki Yokota1,3, Daisuke Hashizume2 and Takao Someya1,2,3,4*
Printable elastic conductors promise large-area stretchable sensor/actuator networks for healthcare, wearables and robotics.
Elastomers with metal nanoparticles are one of the best approaches to achieve high performance, but large-area utilization is limited by diculties in their processability. Here we report a printable elastic conductor containing Ag nanoparticles that are formed in situ, solely by mixing micrometre-sized Ag flakes, fluorine rubbers, and surfactant. Our printable elastic composites
exhibit conductivity higher than 4,000 S cm−1 (highest value: 6,168 S cm−1) at 0% strain, and 935 S cm−1 when stretched up to 400%. Ag nanoparticle formation is influenced by the surfactant, heating processes, and elastomer molecular weight, resulting in a drastic improvement of conductivity. Fully printed sensor networks for stretchable robots are demonstrated,
sensing pressure and temperature accurately, even when stretched over 250%.