碳纳米管/丁苯橡胶复合材料的电学性能

采用喷雾干燥法可制备不同配比的碳纳米管（Carbon nanotubes，CNTs）/粉末丁苯橡胶复合材料，观察CNTs在橡胶基体中的分散情况，检测复合材料的导电性能及介电性能，并进行了简要的理论分析。结果表明:CNTs在橡胶基体中获得了充分均匀的分散，有利于CNTs改性补强作用的发挥。与纯胶样品及填充炭黑（Carbon black，CB）样品相比， 填充CNTs样品在8~18GHz下具有较高的介电常数及低介电损耗。随着CNTs加入量的增加，CNTs/粉末丁苯橡胶复合材料的电导率逐渐升高，当CNTs加入量为60phr（per hundred rubber）时，与纯胶样品及添加60phr CB样品相比，电导率提高近10个数量级；复合材料内部导电同时存在隧道导电机制和渗逾导电机制。采用喷雾干燥法制备的CNTs/粉末丁苯橡胶复合材料，将是一种综合性能良好的新型纳米复合材料，有望在抗静电橡胶、电磁屏蔽及介电材料等领域获得应用。 

Electrical properties of carbon nanotubes/styrene-butadiene rubber composites

The carbon nanotubes (CNTs)/styrene-butadiene rubber (SBR) powder composites filled with different contents of CNTs were prepared by the  spray drying method. The dispersion of CNTs in the matrix was investigated. Electrical and dielectric properties of the composites were tested and the corresponding theoretical analysis was discussed. The results show that CNTs are well dispersed in the matrix，which is beneficial for the reinforcement and modification of CNTs on the rubber matrix. Compared with the pure SBR and composites filled with CB，the composites filled with CNTs present a higher dielectric constant and lower dielectric loss under frequencies of 8~18GHz. The electrical conductivity of the composites filled with CNTs is gradually improved with the augment of filled CNTs. Compared with that of pure SBR and composites filled with 60 phr CB，the electrical conductivity of the composites filled with 60 phr CNTs is enhanced by about 10 orders of the magnitudes. There exist contemporary tunnel and percolation conductive mechanism in the CNTs/SBR composites. Powder SBR composites modified with CNTs could be a new type of nanocomposites with excellent comprehensive properties and will be potentially applied in the fields of antistatic rubber，electromagnetic shield, dielectric materials and so on.