Aminophenoxyphthalonitrile modified MWCNTs/polyarylene ether nitriles composite films with excellent mechanical, thermal, dielectric properties

Abstract

In this work, multi-walled carbon nanotubes (MWCNTs) were firstly surface modified with 3-aminophenoxyphthalonitrile (3-APN) via solvent-thermal method. Subsequently, modified MWCNTs were used to fabricate polyarylene ether nitrile (PEN) based composites through solution-casting technique. From the scanning electron microscope observation of 3-APN@MWCNTs/PEN composite films, 3-APN@MWCNTs had uniform dispersion and good interface compatibility with the PEN matrix. The composites were possessed and improved mechanical properties, such as the tensile strength of the composite with 4 wt% filler increased from 90 to about 110 MPa. The tensile modulus increased from 2300 to about 2750 MPa when the filler loading reached 5 wt%. Besides, the 3-APN@MWCNTs/PEN composite films exhibited excellent thermal stability, the glass transition temperature was about 228 °C and the initial decomposition temperature was beyond 484 °C. Furthermore, the dielectric constant of the composite film increased to 32.2 (50 Hz) and the corresponding dielectric loss was 0.9 with 5 wt% 3-APN@MWCNTs loading. Finally, the dynamic rheological tests were employed to investigate the molecular interaction between 3-APN@MWCNTs and PEN polymer chains.