Interfacial Polarization And Electrical Properties Of Aligned Carbon Nanotubes/Polymer Nanocomposites: The Influence Of Molecular Polarity

Dielectric elastomers(DE) become a research hot point due to high energy density, high electromechanical coupling efficiency, large actuation and so on. For producing DEs with high permittivity (ε’), carbon based filler are often used in filler-polymer matrix composite system. The interfacial polarization is the dominant mechanism to enhance permittivity in composites system, however, interfacial polarization is influenced by factors such as temperature, interface compatible, diameter of fillers,dispersion of fillers, surface polarity of fillers will influence influence the interfacial polarization. For enhancing properties of DE, researchers made a lot investigation to optimise the filler-matrix interface, the most frequently used method is filler organized includes:encapsulation, graft and modification. However, a lot attention was paid to domains of fillers, while there is hardly any investigation about how matrix can affect the interface and electrical properties. Therefore, this research prepared three CNTB/HNBR composites with different matrix molecular polarity to investigate the influence of matrix molecular polarity on interfacial polarization in micro-scale and electrical properties in macro-scale, besides, conclusion of this research can provide guidance for optimising properties of DE.Innovative results of this study are as follows:1. Preparing three composites with different matrix molecular polarity. SEM, TEM and RPA analysis proved that the CNTB disentangle and dispersed in HNBR in the form of single nanotube which is in nanoscale. Besides, filler network structures in HNBR with different acrylonitrile content(ACN%) are similarity, which eliminates the influence of filler dispersion on interfacial polarization and electrical properties.2. We measured Dc/Ac conductivity, dielelctric constant, dielectric loss and impedance of CNTB/HNBR composites, the analysis results shows that composites with higher matrix molecular polarity have higher conductivity, lower percolation threshold value, higher ε’ and ε" and lower impedance.3. We fitted the impedance data into an equivalent circle by using Zview2 software, the fitted results semiquantitative exhibits the interfacial polarization of three composites with different matrix respectively. The analysis results shows that higher matrix molecular polarity lead to more intensity interfacial polarization in micro-scale which further lead to electrical properties in macro-scale.