二硫化钼/多壁碳纳米管/天然橡胶复合材料制备及吸波性能研究

Preparation and absorbing properties of molybdenum disulfide/multi-walled carbon nanotubes/natural rubber composites

采用机械共混法,以天然橡胶(NR)为基体、多壁碳纳米管(MWCNTs)和二硫化钼(MoS2)为填料,制备了MWCNTs/NR、MoS2/NR和MWCNTs/MoS2/NR 3种复合材料,通过扫描电镜、高阻计、矢量网络分析仪和橡胶拉伸试验机分别对复合材料形貌、电导率、电磁参数和力学性能进行表征。结果表明,(1) 填料在MWCNTs/MoS2/NR复合材料中的分散最好;(2) MWCNTs的加入,使得复合材料的电导率增大;(3) 随厚度的增加,复合材料反射峰值对应的频率逐渐向低频方向移动。MWCNTs/MoS2/NR复合材料的吸波性能最佳,反射损耗为-29.59 dB,分别是MWCNTs/NR、MoS2/NR的6.9和17.0倍,有效吸收频宽为3.12 GHz;(4) MWCNTs/MoS2/NR的拉伸强度最高,与填料在基体中的分散好有关。MWCNTs与MoS2在NR中相互促进分散,形成多重损耗机制,优化了复合材料的吸波、导电、力学等多项性能。

Microwave absorbing Materials based on multi-walled carbon nanotubes/molybdenum disulfide/natural rubber (MWCNTs/MoS2/NR) were prepared by mechanical blending. The morphology, electromagnetic parameters and mechanical properties of the composites were investigated by scanning electron microscopy (SEM) and vector network analyzer (VAN) and other instruments. It was found that incorporating of MWCNTs improved the conductivities of the composites, which were 11 orders of magnitude higher than that of pure NR. The reflection loss (RL) of MWCNTs/MoS2/NR composite is up to 29.59 dB which is 6.9 times that of MWCNTs/NR and 17 times that of MoS2/NR, and the effective absorption bandwidth is 3.12 GHz. With the thickness of the sample increasing, the optimized frequency moved toward the lower frequency. Due to the weak interaction between fillers and matrix, the elongation at break of the composites is obviously reduced, the stress at definite elongation improved at different levels, and the tensile strength was not changed much. MWCNTs and MoS2 mutually promoted dispersion in NR, forming multiple loss mechanisms, thus optimizing multiple properties such as microwave absorption capacity.