Fabrication and Properties of Thermoplastic Polyurethane/Silver Parts via Fused Deposition Modeling for Electromagnetic Interference Shielding and Wearable Sensors

With the rapid development of high technology, there is an urgent requirement for multifunctional and flexible intelligent devices. Herein, the segregated thermoplastic polyurethane/silver (TPU/Ag) composite with continuous silver structure were fabricated by a jealous combination of fused deposition modeling (FDM) and selective microwave sintering (SMS). The SMS process significantly improves the mechanical performance of the parts, mainly attributed to the enhanced interfacial bonding strength between heated filaments. Benefiting from the high flexibility and continuous segregated Ag structure of the printed parts, the TPU/Ag composites with 2.34 mm of thickness can achieve an excellent electromagnetic interference shielding effectiveness (EMI SE) of average ≈78.3 dB in X‐band (8.2–12.4 GHz). In addition, the elastic characteristic of the printed parts enabling a prominent stretchable sensitivity under repeated tensile mode. The sensors exhibit high‐sensitive performance (GF = 1900.6 at strain of 9%) and can monitor subtle human activity. The facile and green strategy proposed in this study is highly favorable for the fabrication of functional 3D printed parts with enhanced mechanical strength for the applications of portable electronic devices and wearable smart sensors.