高剪切分散对多壁碳纳米管/VARTM用环氧树脂导电性能的影响

采用高剪切工艺促进了多壁碳纳米管(MWNTs)在环氧树脂(EP)中的分散,借助真空辅助树脂传递模塑技术(VARTM)制备出MWNTs/EP复合材料试样,并研究在制备过程中采用不同高剪切工艺参数对复合材料导电性能的影响.结果表明,在一定范围内,随着高剪切时间或转速的增加,复合材料的导电性能呈现先升高后降低的趋势.在高剪切处理时间30min和转速22 000r/min时分别达到了高剪切时间和转速的最佳分散阈值,当MWNTs的添加量仅为1.5%时,EP的表面电阻率可以降低约5个数量级,但继续增加高剪切的时间或转速,复合材料的导电性能均出现劣化.同时运用扫描电镜(SEM)表征了多壁碳纳米管在环氧树脂中的分散情况.

Influence of High Shear Dispersion on Conductive Properties of MultiWall Carbon Nanotubes/VARTM Epoxy Resin Composites

The dispersion of multi-wall carbon nanotubes (MWNTs) in epoxy resin was facilitated with the assistance of high shear dispersing emulsifier. The MWNTs/EP composites was manufactured using vacuum assisted resin transfer molding (VARTM) technology,and the conductive properties affected by the speed and time were studied. The results showed that the conductive properties of the composite increased at first and then decreased with the increasing high shear dispersing time or speed. A threshold was captured when the high shear dispersing was 30 min and speed was 22 000 r/min. The addition of 1.5% MWNTs (wt. %) can decrease the surface resistance of epoxy resin within 5 orders of magnitude. The effect of dispersion of MWNTs in EP was also verified by scanning electron microscopy (SEM).