中文摘要：

为了探讨纳米蒙脱土对聚乙烯击穿性能和电导特性的影响，采用威布尔（Weibull）统计的方法分析了电介质的击穿场强，利用电导温度谱图分析了不同试样电导的温度特性，用扫描电镜（SEM）和原子力显微镜（AFM）对复合材料的微结构进行了表征。研究了插层温度和电老化对聚乙烯复合材料击穿性能的影响及其电导的温度特性，以及电介质电击穿后结构的变化。结果表明，用蒙脱土对聚乙烯进行改性能明显提高其击穿性能和改善电导特性：与纯聚乙烯相比，聚乙烯／蒙脱土复合材料试样具有明显的极性电介质的损耗特征，而且复合材料试样的绝缘电阻率在50-60℃的温度范围内明显高于低密度聚乙烯（LDPE）的值；而耐电老化性能也有所提高：在电老化66h后，其击穿场强是纯聚乙烯的1．10倍；并且蒙脱土与聚乙烯形成的强的相互作用区像“交联点”等，能明显减少复合材料的电场破坏。可见，纳米蒙脱土的加入有望提高聚乙烯的长期介电强度和耐温等级。

英文摘要：

To investigate the dielectric properties of polymer layered silicate （PLS） nanocomposites, which exhibit excellent thermal and mechanical properties, we prepared the polyethylene/montmorillonite nano-composites by the melting intercalation process, analyzed the electrical breakdown strength by the Weibull statistical analysis, and determined the morphology of the nano-composites by means of scanning electronic microscope （SEM） and atomic force microscope （AFM）. Moreover, we focused on the characteristics of electrical breakdown and electrical conductivity of the nano-composites. The test results indicate that electrical breakdown strength and insulation resistance of LDPE/O-MMT is obviously higher than that of LDPE, after 66 hours electrical aging, electrical breakdown strength of LDPE/O-MMT/C is 1. 10 times that of LDPE. ＂ interaction zones＂ may form in LDPE and MMT such as erosslinking points and it can reduce the electric field damage of nanocomposites. It can be confirmed that polyethylene improved by nano-montmorillonite is provided with much higher dielectric strength and better heat resistance property than those of pure PE.