流道特征尺寸对PP/MWCNTs电磁屏蔽效能的影响研究

Influence of Flow Channel Feature Size on Electromagnetic Shielding Effectiveness of PP/MWCNTs Composites

流道特征尺寸低于400μm的受限加工环境下,成型的制品在微观结构存在高度取向,有利于提高电磁屏蔽效能。以聚丙烯/多壁碳纳米管(PP/MWCNTs)为例,探究不同流道特征尺寸下PP/MWCNTs的微观形态,力学性能和电磁屏蔽效能。结果表明:当流道特征尺寸降低至100μm,剪切层比例高达81.22%。通过取向量化分析,流道特征尺寸从400μm降至100μm时,Herman参数(f)从0.103增至0.381。流道特征尺寸降低有助于提高电磁屏蔽效能,从18.09 dB增至20.94 dB。

In the restricted processing environment with channel characteristic size less than 400 μm, the formed products are highly oriented in the microstructure, which is conducive to the improvement of electromagnetic shielding effectiveness. Taking polypropylene/multi-walled carbon nanotubes(PP/MWCNTs) as an example, the microstructure,mechanical properties and electromagnetic shielding effectiveness of PP/MWCNTs under different channel characteristic sizes were studied. The results show that when the channel characteristic size is reduced to 100 μm, the proportion of shear layer is as high as 81.22%. Through orientation quantitative analysis, the Herman parameters(f) are increased from 0.103to 0.381 when the channel characteristic sizes are decreased from 400 μm to 100 μm. The reduction of channel characteristic size helps to improve electromagnetic shielding effectiveness, increasing from 18.09 dB to 20.94 d B.