T. Liu, G. Xu, J. Zhang, H. Zhang and J. Pang,Dispersion of carbon nanotubes by the branched block copolymer Tetronic 1107 in an alcohol–water solution,Colloid Polym. Sci.,2013,291(3), 691-698.
The dispersion of carbon nanotubes (CNTs) by the branched block copolymer Tetronic 1107 was investigated in mixed solvents consisting of water and one of the following alcohols: ethanol, n-propanol, ethylene glycol (EG), or glycerol (GLY). The maximum concentration of dispersed CNTs (Climit) and the optimum T1107 concentration ( Copt)to disperse the maximum amount of CNTs in different solvents were obtained from UV–vis–NIR absorbance spectra. The addition of ethanol or n-propanol to water dramatically increases the Climit. The value of Copt follows the order: n-propanol–water > ethanol–water > EG–water ≈ GLY–water mixtures. ID/IG was used to characterize the defect density of CNTs dispersed in the mixed solvents, which was investigated by Raman spectroscopy. The ID/IG values in n-propanol–water and ethanol–water mixtures are higher than those in EG–water and GLY–water mixtures. High-resolution transmission electron microscopy is used to confirm a favorable dispersion in the presence of different alcohols.