Effect of inorganic additives on solutions of nonionic surfactants VII. Suspension stability

Comparing the Surface Chemical Properties and the Effect of Salts on the Cloud Point of a Conventional Nonionic Surfactant, Octoxynol 9 (Triton X-100), and of Its Oligomer, Tyloxapol (Triton WR-1339)

“…The ⌬ values of the anions and cations of individual salts are also additive algebraically. The assignment of ⌬ values to individual ions is made at comparable values of an empirical concentration parameter W called molal strength (23,24), defined as W ϭ ⌺mz, [8] where z is the valence of the ions that constitute the salt. Thus, W ϭ 2.0 corresponds to 1.0 m NaNO 3 and to 0.50 m Na 2 SO 4 or Mg(NO 3 ) 2 .…”

“…The practical importance of the CP lies in the fact that suspensions (8), emulsions (9), and ointments and foams (10) stabilized with nonionic surfactants become unstable when heated in the vicinity of the CP, e.g., during manufacturing, steam sterilization, or some end uses. On the other hand, the rate of solubilization by nonionic surfactant solutions increases near their CP (11).…”

Foam Silica Films Synthesized by Calcium Chloride-Assisted Emulsification

“…After addition of salt (at a concentration of 15 g·L –1 ), the measured surface tension does not seem to change, nor does the contact angle. Many studies are relative to the salt influence on the behavior of PEG or block copolymers. − PEG tends to form complexes with salts and these complexes are considered to consist of cations trapped within the PEO helices. Salts decrease the cloud point of PEG polymers and promote their phase separation process. − Considering the concentration of the salt and polymer used in this study (ratio PEO/Ca 1.25 for F-127 and 1.6 for PEG-400), salt could be bound to the polymer and participate in the phase separation process.…”

“…Many studies are relative to the salt influence on the behavior of PEG or block copolymers. − PEG tends to form complexes with salts and these complexes are considered to consist of cations trapped within the PEO helices. Salts decrease the cloud point of PEG polymers and promote their phase separation process. − Considering the concentration of the salt and polymer used in this study (ratio PEO/Ca 1.25 for F-127 and 1.6 for PEG-400), salt could be bound to the polymer and participate in the phase separation process. However, this interaction is probably not decisive in the formation of the emulsion since the use of a cationic surfactant instead of a poly­(ethylene oxide)-containing polymer also leads to similar foam morphologies.…”

Electrostatically controlled isolation of debundled single-walled carbon nanotubes from nanoplatelet dispersant

“…Bigger cations seem to cause the precipitation of both SWCNT and ZrP faster than smaller cations (K + > Na + , Ca 2+ > Mg 2+ ), possibly because that they exhibit faster loading rate in ion exchange process with ZrP nanoplatelets 52,53 and stronger dehydration effect that affect the solubility and stability of nonionic surfactants. 54,55 ii. Dependence on ion valence.…”