Stretchable and Printable Conductive Polymer Composites for Electromagnetic Interference (EMI) Shielding Meshes

Abstract

Stretchable electromagnetic interference (EMI) shielding materials are now urgently required owing to recent advancements and wide applications of flexible electronic devices, which produced severe electromagnetic wave pollution, disturbing normal function of electronic devices and causing harmful responses on human body. However, recent studies on flexible EMI shielding materials failed on achieving high shielding effectiveness, large stretchability and excellent transparency. Herein, patterned EMI shielding meshes were fabricated by screen printing the thermoplastic polyurethane/silver micro-flakes (TPU/Ag) paste on a thin and flexible TPU substrate. The conductive composites were printed into various mesh patterns including square mesh shape, circle mesh shape, serpentine shape, etc. The EMI shielding meshes exhibit high stretchability of 80% before electrical insulation, high shielding effectiveness (SE) value of 45 dB for the square mesh shape. Therefore, the mesh patterned conductive composites with excellent EMI shielding performance, high flexibility and large stretchability are highly promising for applications in flexible and stretchable electronics.