Effect of Chain Unsaturation on the Self-Association of Tri- and Tetraethylene Glycol Octyl Ethers Obtained by Butadiene Telomerization

Abstract

2,7-Octadienyl ethers of tri- and tetraethylene glycol (C(8:2)E(3) and C(8:2)E(4)) have been synthesized by the atom-economical butadiene telomerization of the corresponding poly(ethylene glycols). On one hand, this synthetic path is attractive because it is expeditious and environmentally benign, and on the other hand, it provides unconventional amphiphiles for which the lipophilic chains possess two double bonds. These two unsaturations increase the global hydrophilicity of the compound, which is also highlighted by the modelization of the compounds using the conductor-like screening model for real solvents (COSMO-RS). The behavior of C(8:2)E(3) and C(8:2)E(4) in binary amphiphile/water and ternary amphiphile/oil/water systems is therefore greatly modified compared to that of the conventional fully saturated homologues (C(8)E(3) and C(8)E(4)) that are easily obtained after hydrogenation. This results in a lowered efficiency of the unsaturated compounds for oil solubilization. The usual Winsor-type microemulsion systems are formed, and for the same oil, the DLS investigation of the microstructure of the Winsor I microemulsion does not highlight any difference in the self-association between the unsaturated and saturated compounds.

Nanometer-Size Polyoxometalate Anions Adsorb Strongly on Neutral Soft Surfaces

“…33 Figure 4 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 The self-assembly process between the POM and polar surfaces is not due to pure electrostatic attraction, as observed generally between two species of opposite charges. In other words no ion pair between the POM anion can form with the non-ionic surfactant head.…”

Extended Surfactants Including an Alkoxylated Central Part Intermediate Producing a Gradual Polarity Transition—A Review of the Properties Used in Applications Such as Enhanced Oil Recovery and Polar Oil Solubilization in Microemulsions

“…The results of research carried out in the first decade of the 21st century (Do et al, ) corroborated the polar oil EACN with different kinds of extended surfactants, for instance, of soya oil at EACN = 17.7 ± 0.5, in striking agreement with the originally reported value (Miñana‐Pérez et al, ) of EACN = 18 ± 1. This kind of result clearly indicates that an ester group decreases the EACN by about 10–12 units with respect to the total number of carbon atoms in a tail, a clear consequence of its polarity contribution to the oil (Engelskirchen et al, ; Lai et al, ; Lukowicz et al, , ; Ontiveros et al, ).…”

The Telomerization of 1,3‐Dienes – A Reaction Grows Up

“…A potential field of application for 2,7‐octadienyl‐substituted sugar derivatives is their use as non‐ionic surfactants based on a renewable feedstock . Studies have shown that unsaturated octadienyl chains significantly change the properties of surfactants obtained by this synthetic pathway and that the subsequent hydrogenation of these compounds is mandatory . In contrast, Suisse et al reported that saturated mono‐octyl ethers of glycerol build a separate phase rather than micelles, whereas octadienyl ethers (mono‐telomers, see Scheme ) display a critical micelle concentration and significant reduction of the surface tension …”