Efficient and thin microwave absorption materials fabricated by polyzwitterion wrapped carbon nanotube

Abstract

Carbon nanotube (CNT) has a strong microwave (MW) attenuated ability due to its high ability of dielectric loss. However, the impedance mismatch of pure CNT-based absorber makes MW is earlier reflection than absorption. Herein, it is reported that the polyzwitterion wrapped CNT (PZ@CNT) with core–shell structure is prepared through in-situ polymerization of 1-vinyl-3-imidazole-propane sulfonate. Because the high polarity polyzwitterion shell layer in the polyzwitterion-wrapped CNTs (PZ@CNTs) optimizes the impendence match of CNT between airs and attenuates the energy of the microwave through the zwitterionic dipole and interfacial polarization loss. PZ@CNTs based MW absorbers composited with paraffin exhibit a minimum reflection loss (RLmin) of −44.5 dB with 1.9 mm thickness at 10.7 GHz and an effective absorption band of 4.2 GHz at a small thickness of 1.3 mm exceeding many of previously reported the wrapped CNTs with a single polymer. This work paves a new way to improve the microwave absorbing performance of Carbon nanotube.