Attempts to control depletion in the surfactant-assisted stabilization of single-walled carbon nanotubes

Effect of sodium dodecylsulfate monomers and micelles on the stability of aqueous dispersions of titanium dioxide pigment nanoparticles against agglomeration and sedimentation

“…Such results are consistent with literature reports on the effect of micelles at high concentrations on the stability of dispersions of polymer microspheres [26][27][28]. Even though the existence of depletion forces has been known to cause such flocculation, the concentration ranges where they would produce a major destabilization effect have not been fully understood.…”

“…Both groups used static light scattering for measuring agglomeration rates, and reported Fuchs-Smoluchowski stability ratios W. Tardani et al. showed that single-walled carbon nanotubes were destabilized when the volume fraction of micellar aggregates (SDS micelles or SDS/TX100 mixed micelles) reached a certain threshold [28].…”

Dispersability of Carbon Nanotubes in Biopolymer-Based Fluids

“…To our knowledge, no experimental studies have reported on depletion in CNT/polymer mixtures. However, evidence arising from surfactant/SWCNT systems gave convincing evidence in favor of depletion [47]. Threshold shifts to lower concentrations are in inverse proportion to the particle hydrodynamic volume, and sensitive to ionic strength.…”

“…Even though the adsorbent is preferentially located on the particles' surfaces, some is still present in the bulk. The latter gives rise to an unbalanced osmotic effect, when its volume fraction in such a medium reaches a critical value [47]. Polymers and/or micelles are responsible for unbalanced osmotic effects, which become relevant at concentrations close to the critical threshold.…”

“…More detailed information is given in the original papers, to which the reader is referred. See, in particular [13,31,47,56,58,59,65,66].…”