Improved dielectric properties of poly(arylene ether nitrile) with sulfonated poly(arylene ether nitrile) modified CaCu3Ti4O12

Abstract High‐dielectric and low‐loss materials hold potential for various electronic devices. A prevalent approach to producing high‐dielectric and low‐loss dielectrics is incorporating inorganic ceramic materials with high dielectric constants into a polymeric matrix. However, doping of inorganic ceramic materials results in agglomeration of the inorganic materials and poor interfacial compatibility between the matrix and the dopant, thus limiting their range of application. In this study, sulfonated poly(arylene ether nitrile) (SPEN) functionalized copper calcium titanate (CCTO) (SPEN@CCTO) was synthesized by modifying hydroxylated CCTO with SPEN and then introduced into the PEN matrix offering SPEN@CCTO/PEN. The successful encapsulation of SPEN at CCTO was confirmed through FT‐IR, XRD, and XPS. SEM observation revealed that SPEN@CCTO nanomaterials not only prevented agglomeration of CCTO but also significantly improved interfacial adhesion between the matrix and filler, highlighting the importance of SPEN@CCTO in enhancing the mechanical properties of resulting nanocomposites. Electrostatic permittivity of SPEN@CCTO/PEN and CCTO/PEN composite dielectric materials were evaluated in the frequency range spanning 10 Hz to 1 MHz. In comparison with CCTO/PEN composite dielectric materials, SPEN@CCTO/PEN composites show superior dielectric characteristics, characterized by higher dielectric constants and lower losses in dielectric. The SPEN@CCTO/PEN film's dielectric constant at 10 Hz and electric breakdown strength with 15 wt% SPEN@CCTO were found to be 5.9 and 178.8 kV/mm, respectively. Thereby, the energy storage density of SPEN@CCTO/PEN composite film was calculated to be 0.83 J/cm 3 . In addition, the excellent mechanical properties of SPEN@CCTO/PEN ensured it as promising flexible dielectric materials in the future.