Abstract

In this study, coated pre-oxidized fiber felt composites were prepared using the PU2540 polyurethane as a matrix and adopting a coating technology on the pre-oxidized fiber felt. Firstly, influences of wave-absorbing functional particles on the dielectric properties and shielding effectiveness of single-layer coated pre-oxidized fiber felt composites were analyzed and compared. Secondly, influences of the graphene content on the dielectric properties and shielding effectiveness of graphene coated pre-oxidized fiber felt composites were discussed. Results showed that values of the real and imaginary parts and loss tangent value of the dielectric constant for graphene coated pre-oxidized fiber felt composites were all larger than those of graphite coated pre-oxidized fiber felt composites, that is, the former had a stronger polarization ability, dissipation ability and attenuation ability to electromagnetic waves than the latter. However, the shielding effectiveness of the latter was larger than that of the former, that is, the shielding ability of graphite coated pre-oxidized fiber felt composites was better than that of graphene coated pre-oxidized fiber felt composites. When the graphene content was 15% of the mass of the polyurethane, the value of the imaginary part and loss tangent value of the dielectric constant for graphene coated pre-oxidized fiber felt composites were both the largest, and the dissipation ability and attenuation ability to electromagnetic waves were both the strongest.

摘要

本研究以PU2540聚氨酯为基体，在预氧化纤维毡上采用涂层技术制备了涂层预氧化纤维毡复合材料。首先，分析比较了吸波功能颗粒对单层包覆预氧化纤维毡复合材料介电性能和屏蔽效能的影响。其次，讨论了石墨烯含量对石墨烯包覆预氧化纤维毡复合材料介电性能和屏蔽效能的影响。结果表明，石墨烯包覆预氧化纤维毡复合材料的介电常数实部和虚部值及损耗角正切值均大于石墨包覆预氧化纤维毡复合材料，即前者具有更强的介电常数。极化能力，对电磁波的耗散能力和衰减能力不如后者。但后者的屏蔽效能大于前者，即石墨包覆预氧化纤维毡复合材料的屏蔽能力优于石墨烯包覆预氧化纤维毡复合材料。当石墨烯含量为聚氨酯质量的15%时，石墨烯包覆预氧化纤维毡复合材料介电常数的虚部值和损耗角正切值均最大，其耗散能力和衰减能力均达到电磁波都是最强的。石墨涂层预氧化纤维毡复合材料的屏蔽能力优于石墨烯涂层预氧化纤维毡复合材料。当石墨烯含量为聚氨酯质量的15%时，石墨烯包覆预氧化纤维毡复合材料介电常数的虚部值和损耗角正切值均最大，其耗散能力和衰减能力均达到电磁波都是最强的。石墨涂层预氧化纤维毡复合材料的屏蔽能力优于石墨烯涂层预氧化纤维毡复合材料。当石墨烯含量为聚氨酯质量的15%时，石墨烯包覆预氧化纤维毡复合材料介电常数的虚部值和损耗角正切值均最大，其耗散能力和衰减能力均达到电磁波都是最强的。