Quantifying the Aggregation Factor in Carbon Nanotube Dispersions by Absorption Spectroscopy
Figure 3
Absorbance of the NMP dispersions and the IPA dispersions versus the as-prepared concentration at (a) 1030 nm, and (b) 660 nm, . The dispersions (200 mL each) were sonicated for 20 minutes (energy input of 0.08 KJ/mL) and the spectra for NMP and IPA were measured immediately after sonication. The absorbance of the dispersions in IPA was remeasured 90 minutes after sonication. (c) The molecular extinction coefficient, , was calculated from the slope of the linear fit (dashed line) to the measurements with the dispersions in NMP using the absorbance values less than 1 a.u.
