Improvement of Resistance to Electrical Tree in LDPE by Mixed Addition of Nano-Particles and Azobenzoic Compound

为了提高LDPE在交流电压下的抗电树枝化性能，将偶氮苯甲酸类化合物和纳米Al_2O_3粒子混合加入LDPE中制备了聚合物纳米复合材料。实验结果表明，混合添加提高了树的起始电压。混合加成的增加比例取决于偶氮苯化合物的种类。当复合物与Al_2O_3的质量分数分别为2.0%和3.0%时，复合物的增重率最高，达300%。混合添加物对控制树木的发育也是有效的，特别是在其孵化期。混合添加剂的潜伏期比不添加任何添加剂的标本长2000倍。然而，控制效果显着依赖于化合物的浓度和施加电压的大小。

The Polymer nano-composite was prepared by mixed addition of azobenzoic compound and Al_2O_3 nano-particle into LDPE to improve the electrical treeing resistance under ac voltage application. The experimental results showed that tree initiation voltage was increased by the mixed addition. The increasing ratio for the mixed addition depends on the kind of azobenzoic compound. The highest increasing ratio of 300% was obtained in the mixed addition of the compound and Al_2O_3 at the concentrations of 2.0 wt% and 3.0 wt%, respectively. The mixed addition was also effective for control of tree development especially in its incubation. The incubation period of the mixed addition was2000times longer than that for the specimen without any additive. However, the control effect depended significantly on the concentration of the compound and magnitude of applied voltage.