中文摘要：

为了研究具有优异热、力学性能的聚合物/层状硅酸盐（PLS）纳米复合物的介电性能,采用熔融插层法制备了低密度聚乙烯/蒙脱土（LDPE/O-MMT）纳米复合材料,试验研究了它的击穿性能和耐局部放电性能,并对击穿场强进行了威布尔（Weibull）分析。对比试验表明：加入相容剂的纳米复合材料的击穿强度明显高于纯聚乙烯,尤其是在试验温度为60～90℃的范围内,前者的击穿场强为后者的1.35～1.70倍;在相同测试条件下,纳米复合材料的放电量和放电次数都小于纯聚乙烯。通过对比试验研究证明：纳米蒙脱土改性聚乙烯具有更高的介电强度和更好的耐局放性能。

英文摘要：

The dielectric properties of nanometric dielectrics have attracted much attention since John Lewis published the article, the title is ＂Nanometric Dielectrics＂, on IEEE transactions on dielectric and electrical insulation in 1994. However, the majority of works reported in the literature were involved in comparing the dielectric properties of polymer/inorganic nano-particles composites those of with polymer/inorganic micro-particles composites, and investigation on dielectric properties of polymer layered silicate （PLS） nano-composites, which exhibit excellent thermal and mechanical properties, were rarely found to be reported. In the present paper, the polyethylene/montmoril- lonite nano-composites are prepared by melting intercalation process. The characteristics of electrical breakdown and partial discharge （PD） of the nano-composites are investigated. The Weibull statistical analysis of electrical breakdown strength is performed. The test results indicate that electrical breakdown strength of LDPE/O-MMT is obviously higher than that of LDPE, up to 1.35-1.70 times at the test temperature of 60-90 ℃, especially. The PD tests display that both the amplitude and number of PD are smaller than pure PE under the same test condition. It can be confirmed that polyethylene improved by nano-montmorillonite is provided with much higher dielectric strength and better partial discharge resistance property than those of pure PE.