摘要
采用微纳叠层共挤方法研究了不同含量的多壁碳纳米管(MWCNTs)对聚丙烯/多壁碳纳米管(PP/MWCNTs)介电复合材料微观形貌、结晶行为以及介电性能的影响。结果表明:由于微纳叠层共挤过程中共混物熔体流经倍增器,受到多次分流、剪切作用,使MWCNTs能够在基体PP中分散得更加均匀;MWCNTs在PP基体中起到明显的异相成核作用,MWCNTs含量为2%(质量分数)时,复合材料结晶度较纯PP提高了20%;同时,MWCNTs的加入使PP/MWCNTs复合材料的介电常数大幅提升,介电损耗变化不大。
The effects of different contents of MWCNTs on the microstructure,crystallization behavior and dielectric properties of polypropylene/MWCNTs(PP/MWCNTs)dielectric composites were studied by micro-nanostack co-extrusion method.The results showed that MWCNTs can be dispersed more uniformly in PP matrix due to the multiple shunting and shearing of blends in the process of micro-nano-stacks co-extrusion.MWCNTs played significant role as heterogeneous nucleation in PP matrix.When the content of MWCNTs was 2 wt%,the crystallinity of composite was increased 20%than that of pure PP.In the same time,the addition of MWCNTs increased the dielectric constant of PP/MWCNTs but the dielectric loss did not change significantly.
引文
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