Cyclo‐olefin copolymer (COC) composites containing different amounts of nickel (Ni) and/or nickel‐coated carbon (NiC) hybrid fillers were prepared, and their morphological, rheological, mechanical, dielectric, and X‐band microwave absorption properties were examined. Rheological percolation thresholds for Ni and NiC fillers were determined to be in the range of 45 to 60 and 60 to 75 phr, respectively. Both fillers caused no significant increase in melt viscosity at low shear rates. The minimum filler concentrations to obtain acceptable reflection loss (RL) values (RL < −10 dB) were determined as 60 and 45 phr for the Ni and NiC series of samples, respectively. The minimum RL value (RL_min) and the broadest absorption bandwidth were determined as −52.5 dB and 8.2 to 12.5 GHz, respectively, for the composite sample containing 75 phr of Ni, whereas a similar performance could be obtained by the sample containing 45 phr of NiC. Considerable enhancement in the RL_min value could not be provided by the use of hybrid NiC fillers; however, the absorption bandwidth was enlarged, and the minimum sample thicknesses to obtain an acceptable absorption bandwidth were reduced significantly.

中文翻译：

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镍和镀镍的碳填充环烯烃共聚物复合材料的流变，机械和X波段微波吸收特性

制备了包含不同量的镍（Ni）和/或镀镍碳（NiC）杂化填料的环烯烃共聚物（COC）复合材料，并检查了它们的形态，流变，机械，介电和X波段微波吸收性能。Ni和NiC填料的流变渗透阈值分别确定为45至60 phr和60至75 phr。两种填料在低剪切速率下均不会引起熔体粘度的显着增加。对于Ni和NiC系列样品，获得可接受的反射损耗（RL）值（RL <-10 dB）的最小填料浓度分别确定为60和45 phr。最小RL值（RL _min）和最宽的吸收带宽分别确定为含75 phr镍的复合样品的-52.5 dB和8.2至12.5 GHz，而含45 phr NiC的样品可以获得类似的性能。通过使用混合NiC填料无法显着提高RL _min值；但是，吸收带宽增大了，获得可接受吸收带宽的最小样品厚度也大大降低了。