Abstract：As the third generation insulating materials, polymer nanocomposites exhibit superior electrical performance. The breakdown is one of the key properties in polymer nanocomposites. Many researches have reported that the breakdown characteristics of nanocomposites are superior to the neat polymer and its micro-composites. This paper summarizes the breakdown performance of the first generation polymer nanocomposites, including the bulk breakdown and the surface flashover. The mechanisms of breakdown improvements in nanocomposites are also discussed. Based on the domestic and overseas research status as well as the relative research work in our group, the influencing mechanisms of free volume and charge transport on the breakdown in nanocomposites were proposed. The relationships between trap and breakdown strength or surface flashover voltage are elaborated. After that, it is pointed out that incorporating of nanofillers can tailor the bulk and surface charge transport parameters, and hence improve the bulk breakdown and the surface flashover performances. Finally, further development of the second generation nanocomposites in future was briefly introduced.
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2017, Vol. 32 
