Electric field induced alignment of multiwalled carbon nanotubes in polymers and multiscale composites

Carbon fiber reinforced polymers (CFRPs) have a highly anisotropic electrical resistivity, which limits their use in electrical applications. In this contribution, an electric field was used to align multiwalled carbon nanotubes (MWCNTs) to create preferential conductive pathways within a nanocomposite and a multiscale composite in order to reduce their resistivity. Investigation on epoxy containing MWCNTs have shown that an electric field of 40 V mm⁻¹ or higher applied for 2 h can lead to a reduction of the resistivity parallel to the field up to four orders of magnitude with only 0·01 wt-% loading. In the case of CFRPs reinforced with 0·01 and 0·1 wt-% of MWCNTs, we observed reductions of the through the thickness resistivity of 36 and 99% respectively, when an electric field of 60 V mm⁻¹ was applied for 2 h during the fabrication of the samples.

碳纤维增强聚合物（Carbon fiber reinforced polymers, CFRPs）具有高度各向异性的电阻率，这限制了其在电气领域的应用。本研究采用电场对齐多壁碳纳米管（Multiwalled Carbon Nanotubes, MWCNTs），在纳米复合材料及多尺度复合材料中构建优先导电通路，以降低其电阻率。针对掺杂MWCNTs的环氧树脂体系的研究表明，施加40 V·mm⁻¹及以上的电场并持续2小时，可使平行于电场方向的电阻率降低至多四个数量级，且MWCNTs的负载量仅为0.01 wt.%。在采用0.01 wt.%与0.1 wt.% MWCNTs增强的CFRPs体系中，我们观察到：在样品制备过程中施加60 V·mm⁻¹的电场并持续2小时后，其厚度方向电阻率分别降低了36%与99%。