Highly flexible and ultra-thin carbon-fabric/Ag/waterborne polyurethane film for ultra-efficient EMI shielding. (5th January 2020)

• Record Type: Journal Article
• Authors: Xing, Di; Lu, Longsheng; Xie, Yingxi; Tang, Yong; Teh, Kwok Siong
• Is Part Of: Materials & design. Volume 185(2020)
• Publication Date: 2020-01-05
• Subjects: EMI shielding -- Electroless Ag deposition -- Nonwoven film -- Ultra-thin -- Flexible; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2019.108227
• Languages: English
• ISSNs: 0264-1275

Abstract

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 ( SSE t up to 5808.7 dB cm 2 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. Graphical abstract: Image 1 Highlights: A lightweight, ultra-thin and flexible carbon-fabric/Ag/waterborne polyurethane film with efficient EMI shielding property was prepared. The EMI shielding performance of this film improved by 37.5% through an enhanced- pressing process due to a denser Ag particle structure. This film with 100-min Ag-deposition and enhanced-pressing shows a conductivity of 11986.8 S/cm and an EMI-SE of 102.9 dB at 0.183 mm thickness. The shielding mechanism of this film has been fully discussed, which is actually dominated by reflection. The EMI-SE dropped by 1.87% after ultrasonic treatment, bending test and thermal reliability test demonstrating outstanding reliability.