The stability of suspensions of multiwalled carbon nanotubes in organic solvents in the presence of triton X-165

The stability of suspensions of multiwalled carbon nanotubes in isopropanol, toluene, and p-xylene has been studied. Suspensions of multiwalled carbon nanotubes in isopropanol (unlike those in toluene and p-xylene) display high aggregation stability, which is explained by the formation of repulsive solvation layers as a result of interactions between the polar solvent and nanotube surface. The addition of a nonionic surfactant, Triton X-165, noticeably increases aggregate sizes and accelerates sedimentation processes in nanotube suspensions in isopropanol, while, in toluene and p-xylene, the aggregate sizes decrease and the nanotube suspensions are stabilized.