多壁碳纳米管/聚苯乙烯-聚氯乙烯复合材料的导电特性

用溶液共混法制得了MWNTs/PS-PVC复合材料, 进行了电导率的测试分析。通过对载流子浓度、迁移率的测量以及电导活化能的计算等分析研究了影响MWNTs/PS-PVC复合材料电导率的因素和导电机制。结果表明: 当PS与PVC的质量比为1:1时, MWNTs/PS-PVC复合材料的导电阈值最低; 当MWNTs的质量分数为1.5%, PS在PS-PVC基体中的质量分数为50%时, MWNTs/PS-PVC复合材料的电导率比MWNTs/PVC单一聚合物复合材料的提高了4个数量级。在导电网络的形成过程中, MWNTs/PS-PVC复合材料中形成的与无机化合物超晶格结构类似的n-i-p-i结构, 降低了MWNTs/PS-PVC复合材料的电导活化能, 增加了载流子浓度, 使MWNTs/PS-PVC复合材料电导率显著提高。

Electrical property of MWNTs/PS PVC composites

The multiwalled carbon nanotubes/polystyrene-polyvinyl chloride (MWNTs/PS-PVC) composites were prepared by solution blending, and the electrical property of composites was studied. Through the measurement of concentration of carriers, the mobility and the calculated conductivity activation energy, the influence factors on the composite material conductivity and the electrical conductivity mechanism of MWNTs/PS-PVC composites were analyzed. The results show that when the mass ratio of PS/PVC is 1:1, the sample is found which exhibits the lowest electrical percolation threshold in all the composites. MWNTs/PS-PVC composites with 1.5% mass fraction of MWNTs, the electrical property of the samples changes with the content of PS, the electrical conductivity of the samples containing 50% PS in PS-PVC is improved by 4 orders of magnitude compared with that of MWNTs/PVC composites. During the formation of conductive network, the n-i-p-i alternating structural units in the composite are similar to the super lattice structure of the inorganic compound, reducing the conductivity activation energy and increasing the carrier concentration, which causes the electrical conductivity of MWNTs/PS-PVC composites to improve significantly.