Green Synthesis of Poly(ethylene Glycol) Modified Multi-Walled Carbon Nanotubes and their Dispersibility

Poly (ethylene glycol) modified multi-walled carbon nanotubes were prepared by a green synthesis procedure, including oxidation, acyl chlorination and alcoholysis. All the liquid reagents were recycled by distillation or reduced pressure distillation, and complicated washing or purification was simplified. Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis were used to characterize the samples. The results indicated that PEG was grafted to the functionalized carbon nanotubes (f-CNTs) and the mass percentage of the grafted PEG was about 12%. After sonicating f-CNTs in ethanol, the dispersibility of f-CNTs in ethanol was about 0.46 mg/mL. The stability of f-CNTs in ethanol was also tested by left standing a 0.4 mg/mL f-CNT/ethanol solution, no precipitation was found after 10 days.