Study on preparation and properties of polyimide /MWNTs triple hybrid films

In this paper, polyimide/multi-walled carbon nanotubes(PI/MWNTs) triple hybrid films were fabricated through thermal imine process of pure polyamic acid and polyamic acid hybrid solution. Polyamic acid (PAA) hybrid solution was synthesized via in situ polymerization with 4, 4-diamino diphenyl ether (ODA) and pyromellitic acid dianhydride (PDMA) as monomers in DMAc solvent with MWNTs modified by mixed acid treatment under ultrasonic. The dispersibility of MWNTs in solvent was characterized before and after functionalization; the morphology of the PI/MWNTs hybrid films were investigated by SEM; the tensile strength and elongation at break of triple hybrid films were tested. The results showed that the dispersibility of modified MWNTs in DMAc had been obviously improved and the mechanical properties of the triple hybrid films were also improved.