Synthesis of UV-curable disulfide functionalized polysiloxane for stretchable gold electrodes with microcrack

Stretchable electrodes prepared by conductive layer and elastomer were widely applied in sensors, flexible electronic devices and health detections. The microcracks in conductive layer strained synergistically with the elastomer, achieving linearly changing of conductivity with stretch. However, the interactions between the metal conductive layers and the substrates need to be enhanced for synergistical strain. In addition, the preparation of stretchable electrode with both high gauge factor (GF) and high stretchable conductivity is still a challenge. The study reported the synthesis of lipoic acid functionalized polysiloxane elastomer (LFPSE), which adhered gold nanoparticles to prepare stretchable electrodes. Elastomer were cured through thiol-ene click polymerization and stretchable electrode was prepared through evaporating gold nanoparticles on LFPSE in vacuum. S-Au bond was characterized by Raman spectroscopy and XRD. Tensile conductivity was performed through microcrack propagation of Au. The conductivity of the LFPSE stretchable electrode increased linearly with a maximum strain of 112.7%, and the GF was 127.89. Finally, LFPSE stretchable electrode was applied to detect muscle movement. The study of UV curable polysiloxane elastomer based on thiol-ene with S-Au interaction provided a potential application in wearable flexible electronic devices and stretchable electrodes.