Yang Zenghui, Wu Haihua, Zhang Renjing, Deng Kaixin, Li Yan, Liu Zhi, Zhong Qiang, Kang Yi
Hubei Engineering Research Center for Graphite Additive Manufacturing Technology and Equipment, China Three Gorges University, Yichang 443002, China.
Polymers (Basel). 2022 Jun 22;14(13):2538. doi: 10.3390/polym14132538.
Wave-absorbing materials are developing in the direction of "light weight, wide frequency band, thin layer and high strength", and it is difficult to achieve the synergy between wave-absorbing performance and mechanical properties when graphene absorbent is compounded with a single resin matrix. In this paper, based on the preparation of a new composite absorbing wire with a graphene (GR)/spherical graphite (SG) double absorbent and polylactic acid (PLA)/thermoplastic polyurethane (TPU) double matrix, we proposed a new method to prepare samples for testing the electromagnetic parameters and tensile strength by fused deposition modeling (FDM). Furthermore, the effect of SG/GR ratio on the microwave absorbing properties and mechanical properties of PLA/TPU composites was specifically studied. It was found that when the ratio of SG/GR was small (0:5, 1:4), the dielectric loss (interfacial polarization loss, dipole polarization loss, conductivity loss) and attenuation ability of the composites were stronger, and the impedance matching was better. When the SG/GR ratio was large (5:0, 4:1), the composites had high strength and toughness. When the ratio of SG/GR was moderate (2:3, 3:2), it could retain the absorbing and mechanical properties of the absorbing materials. On the one hand, the SG and PLA/TPU matrix formed an "island structure", which improves the dispersion of GR; on the other hand, the GR and PLA/TPU matrix formed a "core-shell structure", which promotes polarization and multiple scattering.
吸波材料正朝着“轻质、宽频带、薄层和高强度”的方向发展，当石墨烯吸收剂与单一树脂基体复合时，吸波性能与机械性能难以实现协同。本文基于制备一种具有石墨烯（GR）/球形石墨（SG）双吸收剂和聚乳酸（PLA）/热塑性聚氨酯（TPU）双基体的新型复合吸收丝，提出了一种通过熔融沉积建模（FDM）制备用于测试电磁参数和拉伸强度的样品的新方法。此外，具体研究了SG/GR比例对PLA/TPU复合材料微波吸收性能和机械性能的影响。研究发现，当SG/GR比例较小时（0:5、1:4），复合材料的介电损耗（界面极化损耗、偶极极化损耗、电导率损耗）和衰减能力较强，阻抗匹配较好。当SG/GR比例较大时（5:0、4:1），复合材料具有高强度和韧性。当SG/GR比例适中时（2:3、3:2），它可以保留吸波材料的吸收性能和机械性能。一方面，SG与PLA/TPU基体形成“海岛结构”，提高了GR的分散性；另一方面，GR与PLA/TPU基体形成“核壳结构”，促进了极化和多重散射。
