Enhancing electrical, mechanical, and thermal properties of polybenzimidazole by 3D carbon nanotube@graphene oxide hybrid

In the present work, comparison of electrical conductivity, mechanical properties and thermal stability of graphene oxide (GO), multi-walled carbon nanotubes (MWCNTs) and GOMWCNT hybrid reinforced polybenzimidazole (PBI) nanocomposites prepared via one-pot in situ polymerization have been carried out. The influences of the nanofillers content and mass ratio of GOMWCNT hybrid on the tensile performances and dc conductivity of nanocomposite films were evaluated. In contrast to single-phase GO and MWCNTs, the incorporation of GOMWCNT (mass ratio of 1:1) hybrid into PBI matrix endows optimum dispersion of GO nanosheets and MWCNTs together with better synergistic enhancing effects on the resultant performances of nanocomposites. Both tensile strength and dc conductivity of the GOMWCNT/PBI (1:1) nanocomposites enhanced remarkably with addition of 0-5 Wt% GOMWCNT, followed by petty improvement at higher filler content. The highest dc conductivity of 2.43 x 10(-5) S/cm was achieved at 10 Wt% loading of GOMWCNT (1:1) in PBI. The dc conductivity was further enhanced to 1.06 x 10(-3) S/cm upon thermal annealing at 400 degrees C. The tensile strength showed 3-fold increase and the Young's modulus was enhanced by 12-fold with respect to the pure PBI. The reinforcing efficiency of GOMWCNT was predicted using the modified Halpin-Tsai modeling. This work provides a simple method to prepared GOMWCNT/PBI nanocomposite with high electrical conductivity and mechanical properties, which could be explored in potential applications in aerospace structure and aerospace electronics.