Synthesis of ferrocenyl hyper-branched polyethylene for non-covalent dispersion of multi-walled carbon nanotubes and fabrication of flexible carbon nanotubes-based conductive films

Abstract

Ferrocenyl hyper-branched polyethylene (HBPE-g-PFcEMA) was synthesized by chain-walking polymerization followed by atom transfer radical polymerization, and then characterized by ¹H NMR and GPC. HBPE-g-PFcEMA was subsequently employed to disperse multi-walled carbon nanotubes (MWCNTs) in CHCl₃. It was found that the MWCNTs were efficiently dispersed by HBPE-g-PFcEMA at a concentration of 150.4 mg L⁻¹. The dispersibility of the MWCNTs in the presence of HBPE-g-PFcEMA was evaluated by TEM and SEM. The π–π stacking interactions between the MWCNTs and HBPE-g-PFcEMA were confirmed by UV-vis spectroscopy. Fabrication of the flexible conductive film by spin-coating the MWCNTs/HBPE-g-PFcEMA dispersion on a PET substrate was explored. The resultant conductive film showed good conductivity (conductivity = 943.4 S cm⁻¹). Furthermore, its good conductivity was retained even after being twisted or bent. Thus, the conductive film might find its potential application in flexible electronics.