Carelo Jean C, Soares Bluma G, Schmitz Debora P, Henriques Ruan R, Silva Adriana A, Barra Guilherme M O, Barthem Vitoria M T S, Livi Sebastien
Centro de Tecnologia, COPPE-PEMM, Universidade Federal do Rio de Janeiro, Bl. F, Rio de Janeiro 21941-598, Brazil.
Centro de Tecnologia, Instituto de Macromoléculas, Universidade Federal do Rio de Janeiro, Bl. J, Rio de Janeiro 21941-598, Brazil.
Molecules. 2025 Feb 20;30(5):985. doi: 10.3390/molecules30050985.
Magnetic ionic liquid (MIL) based on alkyl phosphonium cation was used as a curing agent for developing epoxy nanocomposites (ENCs) modified with a graphene nanoplatelet (GNP)/carbon nanotube (CNT) hybrid filler. The materials were prepared by a solvent-free procedure involving ball-milling technology. ENCs containing as low as 3 phr of filler (GNP/CNT = 2.5:0.5 phr) exhibited electrical conductivity with approximately six orders of magnitude greater than the system loaded with GNP = 2.5 phr. Moreover, the use of MIL (10 phr) resulted in ENCs with higher conductivity compared with the same system cured using conventional aliphatic amine. The filler dispersion within the epoxy matrix was confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electromagnetic interference shielding effectiveness (EMI SE), evaluated in the X- and Ku-band frequency range, revealed a great contribution of the absorption mechanism for the ENC containing the hybrid filler and cured with MIL. Moreover, the best microwave-absorbing response was achieved with the ENC containing GNP/CNT = 2.5/0.5 phr, and cured with ML, which a minimum RL of -23.61 dB and an effective absorption bandwidth of 5.18 GHz were observed for thickness of 1.5 mm. In summary, this system is a promising material for both civilian and military applications due to its simple and scalable nanocomposite preparation method, the lightweight nature of the composites resulting from the low filler content, the commercial availability and cost-effectiveness of GNP, and its high electromagnetic wave attenuation across a broad frequency range.
基于烷基鏻阳离子的磁性离子液体（MIL）被用作固化剂，用于开发用石墨烯纳米片（GNP）/碳纳米管（CNT）混合填料改性的环氧纳米复合材料（ENC）。这些材料通过涉及球磨技术的无溶剂工艺制备。含有低至3 phr填料（GNP/CNT = 2.5:0.5 phr）的ENC表现出的电导率比负载2.5 phr GNP的体系高出约六个数量级。此外，与使用传统脂肪胺固化的相同体系相比，使用MIL（10 phr）得到的ENC具有更高的电导率。通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）确认了填料在环氧基质中的分散情况。在X波段和Ku波段频率范围内评估的电磁干扰屏蔽效能（EMI SE）表明，对于含有混合填料并用MIL固化的ENC，吸收机制起了很大作用。此外，含有GNP/CNT = 2.5/0.5 phr并用ML固化的ENC实现了最佳的微波吸收响应，对于1.5 mm的厚度，观察到最小反射损耗（RL）为-23.61 dB，有效吸收带宽为5.18 GHz。总之，由于其简单且可扩展的纳米复合材料制备方法、低填料含量导致复合材料的轻质特性、GNP的商业可用性和成本效益以及其在宽频率范围内的高电磁波衰减，该体系对于民用和军事应用都是一种有前景的材料。
