A Flexible Electric–Magnetic Bilayer Composite Film for Absorption-dominant Electromagnetic Interference Shielding
발표자
조고은 (한국생산기술연구원)
연구책임자
김봉기 (건국대학교)
홍성우 (한국생산기술연구원/한국과학기술연구원)
초록
내용
The increasing demand for high-frequency 5G electronics necessitates flexible electromagnetic interference (EMI) shielding materials that exhibit high absorption and durability. In this study, we developed a bilayer composite film combining a thermoplastic polyurethane (TPU)/Carbonyl Iron Powder (CIP) absorption layer with a carbon nanotubes (CNTs)/PBTTT conductive layer. This structure integrates magnetic and dielectric losses with controlled conductivity to achieve absorption-dominant shielding. The film exhibited a high absorption shielding effectiveness (SEA) of 55 dB with a low reflection shielding effectiveness (SER) of 3 dB. It maintained over 95% of its total shielding effectiveness (SET) and reflectance below 0.5 after 10,000 folding cycles, confirming excellent folding reliability. A thermal stability test at 150 °C for 1 h demonstrated over 90% SET retention. These results highlight the potential of this bilayer system for next-generation EMI shielding in 5G-related devices.