In situ fabrication of MWCNTs reinforce dielectric performances of polyarylene ether nitrile nanocomposite

In this report, the dielectric properties of polyarylene ether nitrile (PEN)/multi-walled carbon nanotubes (MWCNTs) polymer composites were reinforced via in situ fabrication protocol for MWCNTs. The silanized MWCNTs were surface grafted with phenolphthalin (PPL), which is also one monomer involved in PEN synthesis. This is the premise for PPL can initiate cross-link behavior with the complex PEN and we called it as reactive MWCNTs. Therefore, the composite of PEN and reactive MWCNTs was readily fabricated by solution-casting method and the performance of this unique system was characterized by a range of different techniques. Fourier transform infrared spectroscopy confirmed that the MWCNTs have been bonded with PPL and silane functionalization agent. Based on the observation of scanning electron microscope, it was noted that the forming of reactive MWCNTs could improve the dispersion interfacial compatibility of PEN/MWCNTs nanocomposites. Consequently, the dielectric properties were improved, as lower dielectric loss and higher dielectric constant simultaneously obtained using reactive MWCNTs filler. Moreover, the results of thermal and mechanical performance tests provided additional evidences that the reactive MWCNTs synthesized via in situ fabrication can better reinforce PEN nanocomposites.