聚丙烯/膨胀石墨/碳纳米管复合材料电性能、微观结构及其流变学研究

Study on Electrical,Morphology and Rheological Properties of PP/Expanded Graphite/Carbon Nanotubes Composites

研究了以膨胀石墨(EG)和多壁碳纳米管(MWNT)共同填充聚丙烯(PP)体系的电性能、微观结构及其流变行为。结果表明,EG和MWNT的协同导电作用显著降低了复合材料的体积电阻率和逾渗阀值,当MWNT用量为5 phr、EG为10 phr时,与PP/EG(15 phr)材料相比,复合材料的体积电阻率降低了1 600倍,通过其低频区流变行为的研究,表明EG同MWNT协同形成了更完善的三维网络结构,扫描电镜(SEM)分析表明,MWNT在复合体系中起到桥连作用,连接基体与EG,以及EG片层与片层,因此获得了更好的导电特性。

Expanded graphite （EG） and multi-walled carbon nanotubes （MWNT） were used as co-carbon fillers in PP based composites.The effect of co-carbon fillers on the electrical,rheological and morphology of polypropylene （PP） based composites was investigated in this paper.The experimental results showed the electrical resistivity and threshold value of seepage were decreased by the effect of EG and MWNT.When the composite containing 10 phr EG and 5 phr MWNT,the electrical resistivity was decreased by 1 600 times than that of the PP/EG composite with contained 15 phr EG alone.This indicated that EG formed the 3-D bulk conductive network.SEM showed the MWNT were intercalated between the EG layers or bridged between adjacent EG flakes and matrix,resulting in an additional conductive pathway,which were further confirmed by rheological and morphology study of the composites.