Highly aligned nonwoven vapor grown carbon fibre based polyurethane fibrous membrane for direction-dependent microwave shielding
Abstract Highly aligned nonwoven vapor grown carbon fibre (VGCF) based polyurethane (PU) fibrous membrane (VGCF@PUFM) was fabricated by rotation spinning based on DMF-H 2 O exchange for directional microwave shielding. This VGCF@PUFM showed obviously different electrical conductivity and mechanical strength in parallel and perpendicular directions. Variational microwave shielding effectiveness (SE) could be observed by changing the rotation angles of VGCF@PUFM with vibrational direction of electromagnetic (EM) wave. There was the shielding difference more than 10 dB (above 20 dB in 0°, below 8 dB in 90°). Greater shielding effectiveness could be expected by enhancing the anisotropy of electrical conductivity of the VGCF@PUFM. In addition, oriented alignment of VGCF in fibre is promising for further improvement of the electrical conductivity in fibre direction.