Ref.: MCoMeim05-001

A novel ternary composite of PAni/CNT/GNP in EVA matrix: A high-performance material for microwave absorption with low weight and high flexibility

Apresentador: Loan Filipi Calheiros Souto

Autores (Instituição): Calheiros Souto, L.F.(Universidade Federal do Rio de Janeiro); Soares, B.G.(Universidade Federal do Rio de Janeiro);

Resumo:
The advancement of microwave-absorbing materials is critical for applications that require electromagnetic interference shielding, stealth capabilities, and radar absorption. This paper describes the synthesis and characterization of a novel ternary composite integrating polyaniline (PAni), carbon nanotubes (CNTs), and graphene nanoplatelets (GNPs) within an ethylene-vinyl acetate (EVA) copolymer matrix. The composites were fabricated via in situ polymerization of aniline in the presence of a toluene dispersion of CNT/GNP hybrids and EVA. Employing a vector network analyzer, the microwave absorption properties were assessed across the 8.2-18 GHz frequency range. The study revealed that the incorporation of a mere 0.8 wt% CNT/GNP hybrid, at an optimal mass ratio, significantly augmented the conductivity by over four orders of magnitude in comparison to the EVA@PAni blend. Furthermore, the composite with a CNT/GNP ratio of 0.3:0.7 manifested the lowest reflection loss of -40.55 dB at 16.31 GHz. In contrast, the composites with CNT/GNP ratios of 0.0:1.0 and 0.7:0.3 demonstrated the widest effective absorption bandwidth (RL < -10 dB), covering nearly the entire Ku-band. Owing to their exceptional flexibility, reduced mass, and superior microwave absorption efficacy, these composites show considerable promise for microwave absorption applications.