High-Durability Cellulose-Based Composite Paper with Superior Electromagnetic Interference Shielding

Highly efficient electromagnetic interference (EMI) shielding materials are critical for portable hardware and flexible electronics, where mechanical durability often poses challenges. Here, the excellent wear resistance and flexibility of thermoplastic polyurethane are utilized to provide a "protective layer" for EMI equipment. A carbon nanotube/cellulose/thermoplastic polyurethane (CNT/paper/TPU) composite paper with a three-layer structure was prepared using a coating method. Strong hydrogen bonds between CNTs, cellulose, and TPU ensured robust integration. The composite, with a thickness of 0.54 mm and conductivity of 1040 S/m, achieved exceptional EMI shielding effectiveness of 69.0 dB. It demonstrated durability against water, solvents, bending, and friction while maintaining shielding performance. Furthermore, its excellent mechanical properties and fatigue resistance significantly enhance equipment lifespan. Therefore, it is expected that this work will open a simple strategy for developing materials with excellent durable EMI shielding properties.