Among the various requirements that high voltage direct current (HVDC) insulation materials need to satisfy, sufficiently low electrical conductivity is one of the most important. The leading commercial HVDC insulation material is currently an exceptionally clean cross-linked low-density polyethylene (XLPE). Previous studies have reported that the DC-conductivity of low-density polyethylene (LDPE) can be markedly reduced either by including a fraction of high-density polyethylene (HDPE) or by adding a small amount of a well dispersed, semiconducting nanofiller such as Al₂O₃ coated with a silane. This study demonstrates that by combining these two strategies a synergistic effect can be achieved, resulting in an insulation material with an ultra-low electrical conductivity. The addition of both HDPE and C₈–Al₂O₃ nanoparticles to LDPE resulted in ultra-insulating nanocomposites with a conductivity around 500 times lower than of the neat LDPE at an electric field of 32 kV/mm and 60–90 °C. The new nanocomposite is thus a promising material regarding the electrical conductivity and it can be further optimized since the polyethylene blend and the nanoparticles can be improved independently.

在高压直流（HVDC）绝缘材料需要满足的各种要求中，足够低的电导率是最重要的条件之一。目前，领先的商用HVDC绝缘材料是非常清洁的交联低密度聚乙烯（XLPE）。先前的研究报道，通过添加一部分高密度聚乙烯（HDPE）或添加少量分散良好的半导体纳米填料，可以显着降低低密度聚乙烯（LDPE）的直流电导率。₂ ö ₃涂有硅烷。这项研究表明，通过结合这两种策略，可以实现协同效应，从而获得具有超低电导率的绝缘材料。在LDPE中同时添加HDPE和C ₈ -Al ₂ O ₃纳米颗粒会导致超绝缘纳米复合材料，在32 kV / mm和60-90°C的电场下，其电导率比纯LDPE低约500倍。因此，新的纳米复合材料在电导率方面是一种很有前途的材料，并且由于可以单独改善聚乙烯共混物和纳米颗粒，因此可以进一步优化。