碳化硅改性三元乙丙橡胶复合材料的非线性电阻特性

Nonlinear resistance characteristics of silicon carbide modified ethylene propylene diene monomer composites

采用纳米碳化硅(SiC)或SiC晶须改性的三元乙丙橡胶制备复合材料,研究了SiC用量对复合材料体积电阻率的影响,分析了非线性电阻产生的机理。结果表明,在低场强区(电场强度小于10 kV/mm),复合材料的电阻率随着SiC用量的增加缓慢下降;在高场强区(大于20 kV/mm),复合材料的电阻率随着SiC用量的增加快速下降;SiC用量增大时,SiC粒子间的距离减小,非线性效果增强;采用大长径比的SiC晶须作为改性材料可以降低非线性电阻的临界电场强度。

Ethylene propylene diene monomer was modified by nano silicon carbide(SiC)and SiC whisker,the influence of SiC content on bulk resistivity was studied,and the mechanism of nonlinear resistance was analyzed.Results showed that resistivity of the composites decreased slowly with increasing of SiC content in the low field strength region(electric field intensity less than 10 kV/mm)and decreased rapidly in high field strength region(electric field intensity more than 20 kV/mm).The nonlinear effect was enhanced by decreasing the distance between SiC particles with the increase of SiC content and the critical electric field intensity of nonlinear resistance could be reduced by using SiC whisker with high aspect ratio as modified material.