The e ectiveness of carbon nanotubes (CNT) deagglomeration by rapid expansion of
supercritical suspensions (RESS) in nitrogen and carbon dioxide fluids was studied in this work.
Two di erent mechanisms of deagglomeration were proposed for these two fluids at various
temperature and pressure conditions. Ultrasound attenuation spectroscopy was applied as an express
method of determining median diameter and aspect ratio of CNTs. At least twofold reduction of
the diameter was shown for CNT bundles processed by RESS technique. Aspect ratio of processed
CNTs, calculated from acoustic attenuation spectra, increased to 340. These results were in a good
agreement with atomic force microscopy data.
