LDPE／CPE／炭黑三相复合导电体系的电学性能

The Electrical Properties of LDPE/ CPE/ Carbon Black Electrical Conductive Composites

研究了ＬＤＰＥ／ＣＰＥ／炭黑三相复合导电体系的导电性能和电流－电压特性。实验结果表明复合体系具有明显的导电渗滤效应，在共混比ＬＤＰＥ／ＣＰＥ＞５０／５０时，导电性能随ＣＰＥ含量增加而显著提高，这主要是由于炭黑粒子在ＬＤＰＥ和ＣＰＥ两组分中的分布不均匀性所致。复合体系的电流－电压特性在低电压下呈欧姆特征，在电压高于一定值后呈现非欧姆特征。非线性欧姆行为主要是由于炭黑粒子之间间隙电阻的负温度系数效应（ＮＴＣ）所致。随着炭黑和ＣＰＥ含量的增加，复合体系的非线性欧姆行为减弱。

In this Paper, the electrical conductivity and current-voltage (I-U) characteristics of LDPE / CPE / CB electrical conductive composites were studied. It shows that the composites possess notable Percolation effect. Above the blend ratio of LDPE / CPE =50 / 50, the electrical conductivity of composites is remarkably improved as CPE content increases, which is main caused by the heterogeneous distribution of carbon black particles in the two incompatible polymer components, i.e. LDPE and CPE.The I-U characteristics of composites can be divided into two regions, ohmic and nonohmic, according to the test voltage. The non-linear ohmic characteristic of I-U of composites, caused by the negative temperature coefficient (NTC) effect of resistance of gap between carbon black particles, decreases as carbon black and CPE contents increase.