Organic Additives and Electrolytes as Cloud Point Modifiers in Octylphenol Ethoxylate Solutions

Abstract

Cloud point measurements of nonionic surfactant Triton X-100, an octylphenol ethoxylate, were carried out in the absence and presence of various organic additives such as n-alkanols (methanol, ethanol, propanol and butanol), glycols (ethylene glycol, diethylene glycol and triethylene glycol), glycol ethers (ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and ethylene glycol monobutyl ether (EGMBE)) and electrolytes (LiCl, KCl, NaF, NaCl, NaBr, NaI, MgCl 2 and AlCl 3 ). The combined effect of these organic additives and electrolytes on cloud point (CP) measurement was also investigated. The effect of nature of cation, anion and valency of cation on CP is also reported. Among the n-alkanols and glycol ethers as additives, n-butanol and EGMBE were found to decrease the CP while all other additives increase the cloud point. The addition of electrolytes (LiCl, NaCl and KCl) to the solution of Triton X-100 (TX-100) decreases the CP but the rate of decrease in CP with concentration does not follow the lyotropic series of effect. Sodium halides (except NaI) also decrease the CP and the rate of decrease follows the lyotropic series of effect even in the presence of organic additives. NaI is a water structure breaker, hence it increases the cloud point. Further, cations of increasing valency lessen the depression in CP of TX-100 with the rate of decrease in CP following the order Na + [ Mg 2+ [ Al 3+ even in the presence of organic additives.

Influence of the Mixed Propoxy/Ethoxy Spacer Arrangement Order and of the Ionic Head Group Nature on the Adsorption and Aggregation of Extended Surfactants

“…it is independent of the arrangement of the EO and PO groups in the polyalkoxide chain. However, a slight cloud point decrease was observed as expected [30] as salinity was increased. The sequential arrangement intermediate was found to be very slightly more hydrophilic at zero salinity with a cloud point at 27°C versus 25.5°C for the homogeneous arrangement one, which is a difference at the limit of significance, and even less when salt is added.…”

Phase Separation of Triblock Polymers and Tritons in the Presence of Biomolecules

“…Decreases in the CPs for these systems follow the order: Ser > Pro > Gly > Thre > Val. The results can be explained by considering two factors which mainly control the cloud point variation, namely solvation capacity and the hydrophobicity of micelles in the aqueous environment [29,30]. Decreases in the CP of TBP and tritons can be related to decreased solvation capacity of the micelles in the presence of amino acids.…”

Investigations on microstructural changes in pH responsive mixed micelles of Triton X-100 and bile salt

“…Effects of salts [27], acids [28], hydrotropes [29] and other additives on TX-100 solutions have also been examined. The widespread applications of TX-100 in various fields and biologically compatible features prompted us to select TX-100 micellar system as a model to further understand effect of various stimuli on mixed aqueous solutions with bile salts.…”