کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
820989 | 906735 | 2011 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Morphological changes of carbon nanotubes in polyethylene matrices under oscillatory tests as determined by dielectrical measurements Morphological changes of carbon nanotubes in polyethylene matrices under oscillatory tests as determined by dielectrical measurements](/preview/png/820989.png)
By combining a high sensitive dielectric sensor into a parallel plate rheometer, the time evolution of the dielectric properties of polyethylene/carbon nanotube composites was measured in the molten state under oscillatory shear. Composites with single- (SWCNT) or multiwall (MWCNT) carbon nanotubes initially decrease its conductivity proportional to the oscillatory shear-strain applied. After this initial drop, some composites increase the conductivity under these non-quiescent conditions reflecting a possible shear-induced agglomeration process. The latter based on the complex permittivity spectrum showing a shortening in the CNT–CNT distances in these composites after shear. At concentrations below the electrical percolation threshold, the presence of both SWCNTs and MWCNTs reduces the DC conductivity of the molten matrices. This result shows that carbon nanotubes can act as a scavenger for impurities or additives present in commercial polyethylenes.
Journal: Composites Science and Technology - Volume 71, Issue 10, 7 July 2011, Pages 1361–1366