Decoration of reduced graphene oxide with dandelion-like TiO2 and their dielectric properties in poly(arylene ether nitriles) composites

Novel dandelion-like titanium oxide (TiO₂) decorated reduced graphene oxide (rGO@TiO₂) hybrids were obtained by a one-step solvent-thermal reduction of GO and tetrabutyl titanate simultaneously. The hybrids were used as a novel filler for high performance poly(arylene ether nitriles) (PEN) composites. The thermal stability and morphological properties of the PEN composites were, respectively, investigated by the thermo gravimetric analysis and scanning electron microscope, aiming at examining the effect of surface decoration on the dispersion of rGO@TiO₂ in PEN matrix. The results indicated that the rGO@TiO₂ present better dispersion in the PEN matrix. Meanwhile, the derived composite films exhibited high thermal stability with initial decomposition temperatures (T _id ) in the range of 477–487 °C. DSC curves showed that the glass transition temperatures were in the range of 219–227 °C. Moreover, all of the composite films also showed excellent flexibility and mechanical properties. The tensile modulus and strength were increased about 4 and 6 % with 5 wt% rGO@TiO₂ loading, respectively. More importantly, for 30 wt% rGO@TiO₂ reinforced PEN composite film, the dielectric permittivity dramatically increased from 3.8 to 81 at 1 kHz.