Highly flexible and ultra-thin carbon-fabric/Ag/waterborne polyurethane film for ultra-efficient EMI shielding

Abstract

We report in this work an ultra-thin and flexible carbon-fabric/Ag/waterborne polyurethane film (named CEF-NF/Ag/WPU film) that exhibits ultra-efficient EMI shielding property using electroless Ag plating combined with the enhanced-pressing process. The optimal CEF-NF/Ag/WPU film (0.183 mm) displays an ultra-high electrical conductivity of 11986.8 S/cm and a superior EMI-SE of 102.9 dB, which demonstrates the Ag deposition can effectively improve the electrical and EMI shielding performance. Compared with the film without an enhanced-pressing, the EMI-SE of a CEF-NF/Ag/WPU film with an enhanced-pressing showed an increase of about 37.5%. The porous structure deposited with Ag particles coating endows this composite film with remarkable EMI-SE at a thin thickness and lightweight (SSEt up to 5808.7 dB cm2 g−1) which outperforms most works. At last, this CEF-NF/Ag/WPU film performs outstanding reliability after ultrasound treatment, bending test and thermal reliability test. In summary, this film has great potential in the fields of wearable devices and flexible materials. Keywords: EMI shielding, Electroless Ag deposition, Nonwoven film, Ultra-thin, Flexible