Lyophilic properties of surfactant-rich phases of polyethoxylated alkylphenols formed at cloud point temperature

Solution behavior of mixed systems based on novel amphiphilic cyclophanes and Triton X100: Aggregation, cloud point phenomenon and cloud point extraction of lanthanide ions

“…7 indicate the increase of CP temperature with the lengthening of the polyoxyethylene chains (C9E8 < C9E12 < C9E16) and with the growth of C9Em concentration. This regularity is rather awaited and is in good agreement with the literature data [10][11][12][13][14]. According to literature [10,11] the CP temperature of conventional non-ionic surfactants should decrease with increasing of alkyl carbon chains.…”

“…This phenomenon is attributed to a dehydration of the polyoxyethylene chains at a definite temperature, which is called CP temperature. The latter value characterizes the key property of non-ionic micellar solutions, closely connected with the surfactant structure [10][11][12][13][14]. The effect of the mixed aggregation on CP phenomenon is also highlighted in the literature [11,15,16].…”

Determination of Allura red in food samples after cloud point extraction using mixed micelles

“…The effectiveness of the cloud point extractions is due to its high selectivity and the possibility of obtaining high coefficients of absolute preconcentration while analysing small sample volumes. Besides, the cloud point extraction with non-ionic surfactants insures the low-cost, simple and accurate analytic procedures (Doroschuk, Lelyushok, Rakhilchuk, & Kulichenko, 2006). This type of extraction by the cloud point method was initially described by Watanabe and Tanaka for the preconcentration of Zn(II) using 1-(2-pyridylazo)napthol (PAN) as a ligand and PONPE as an extractant.…”

Synthesis and aggregation properties of new biodegradable amphiphilic derivatives of p-tert-butylphenol for green separation of Gd(III) ions

“…The latter phase transition is followed by a phase separation, which makes solutions turbid and thus is called the cloud point (CP) phenomenon [13,14]. These phase transitions are greatly affected by concentration and external conditions, such as temperature, pH and ground salts [13][14][15][16][17][18]. The structure of surfactant molecules has great impact in a triggering event of the phase transitions.…”

“…The clustering and further CP phenomenon is mainly induced by a temperature rise for nonionic surfactants [13][14][15], while a counterion effect is of particular impact in both the micellization and the clustering of micelles for ionic ones [16][17][18]. A plenty of works are aimed at revealing the correlation of the phase transitions in solutions of nonionic and ionic surfactants with both nature and size of their hydrophilic moieties [15,18,19]. It is worth noting that phase transitions in aqueous solutions of surfactants and their binding with metal ions are of great significance from both fundamental and practical points of view.…”