Surface‐Engineered Liquid Metal Particles for Printing Stretchable Conductive Composites with Enhanced Stability Under Different Strain Rates

• DOI: 10.1002/admt.202301324
• Publication Date: 2023-09-18T05:09:59Z
• Authors: Ren‐Mian Chin; Youngshang Han; Mohammad H. Malak...
• Keywords: Stretchable electronics; Flexible Electronics; Liquid metal

Abstract Integrating liquid metal (LM) particles into compliant polymers presents an innovative approach for developing intelligent and adaptable systems in stretchable electronics, wearable devices, soft robotics, other emerging technologies. However, the inherent electrically insulative nature of these solid‐liquid composites, compounded by gallium oxide shell surrounding LM droplets, poses a significant challenge establishing conductive pathways, especially small droplet sizes ultrasoft elastomers. Here, interface modification that addresses this bottleneck enables synthesis highly printable composites with microparticles (<2 µm) is presented. Polyvinylpyrrolidone (PVP) used to functionalize inclusions, weakening particle‐matrix interface, facilitating formation percolating network under tensile strain. Optimized parameters result printed traces excellent electrical conductivity (0.2 Ω cm −1 ), ultra‐high elongation at break (>900% strain), minimal resistance change (≈131%). Furthermore, comprehensive study electromechanical response conductors various strain rates reveals their exceptional stability dynamic loading conditions, surpassing performance composed sprayed metal. Finally, potential application multifunctional materials circuitry, addressing demand high stretchability demonstrated.