Carbon Nanotube Dispersions
Carbon nanotubes have unique characteristics, but to express them, they must be dispersed individually. To take full advantage of the exceptional characteristics of single-walled carbon nanotubes, the tubes must be untangled as completely as possible. SWNTs like other nanoparticles show very high forces of attraction so that a powerful and effective technique is necessary for reliable deagglomeration and dispersion. While common mixing techniques do not provide the intensity necessary to untangle SWNTs without damaging them, there is evidence that high power ultrasound destroys and disperses SWCNTs. The cavitational shear forces generated by ultrasound are powerful enough to overcome the bonding forces, while the intensity of the ultrasound can be precisely adjusted to avoid damage from SWCNTs. Carbon nanotubes have insolubility in organic solvents and water. There are very few studies on the structure of dispersions (emulsions), although they are numerous in type and used around the world in countless applications.