炭黑/硅橡胶导电复合材料微观结构及其导电特性

Microstructure and conductive characteristics of carbon black/silicone rubber conductive composites

对炭黑/硅橡胶导电复合材料的微观结构及导电特性进行了研究。以液体硅橡胶为绝缘基体、纳米导电炭黑颗粒为填充材料制作的复合材料具有优良的导电特性,通过实验测试获得了不同炭黑含量下复合材料的电阻率,当炭黑质量分数>4%时,可获得较好的导电性。利用电子扫描系统对炭黑颗粒在硅橡胶基体中的微观结构分布进行了观察,观察发现纳米炭黑颗粒主要以"团聚体"及与之相连的"链条"结构两种形式存在,并不是均匀规则的。将"团聚体"与"链条"结构简化为可变形的"大颗粒",在此基础上建立了相应的导电模型。

The microstructure and conductive characteristics of carbon black/silicone rubber conductive compos-ites were studied.The composites based on insulating silicone rubber filled witch conductive nano carbon black particles had a conductive property.The resistivity of the composites under different carbon black content rela-tionship was obtained and when carbon black mass fraction was greater than 4%,the electrical conductivity were better.The carbon black particles which were not uniform rules appear as two kinds of structure-“aggre-gate”and “chain”which connects with “aggregate”according to SEM images.The “aggregate”and “chain”were simplified to “large particles”structures which can be deformed and the carriers transfer between the“large particles”through mutual contact and the tunneling effect;assumptions,the conductive model was to es-tablish.