Surface and micelle properties of novel multi-dentate surfactants

Surface Activity of Ethoxylate Surfactants with Different Hydrophobic Architectures: The Effect of Layer Substructure on Surface Tension and Adsorption

“…In contrast with the earlier work by Eastoe et al, − , which focused on demonstrating that maximizing the number of CH 3 groups in branched-chain ionic surfactants is a good route for creating surfactants that have very low σ lim at the A–W interface, our results show that increasing the number of methyl groups in the ethoxylated surfactants brings with it the disadvantage of increasing the CMC. Thus, C 12 E 6 has one methyl group, C 4 C 8 E 6 has two methyl groups, and 3,5-di- t -C 4 ϕE 5 has six, yet all three have similar values of σ lim of about 30 mN m –1 .…”

Characterization and micellization of rhamnolipidic fractions and crude extracts produced by Pseudomonas aeruginosa mutant MIG-N146

“…Therefore, the larger pC 20 is, the more efficient the surfactant is [36,37]. As shown in Table 2, the highest value with pC 20 of 5.3 was obtained for RL-F2, followed by the crude extracts and RL-F1, which represented a sequence of a change in surface excess concentration.…”

Biscationic bicephalic (double-headed) amphiphiles with an aromatic spacer and a single hydrophobic tail

“…Structures in this class include alkyl malonates [19,20], alkyl tricarboxylates [21], rigid bridged polycyclic dicarboxylates [22], sugarderived neutral or anionic surfactants [23], α-sulfonated fatty acid esters [24][25][26], those with two or three trimethylammonium [27][28][29][30][31], or pyridinium [32][33][34] groups connected via ester linkers, and pH-sensitive [35] triamines [36,37] connected via amide linkers. Among the important findings of studies on these amphiphiles are the following: (1) they can form micelles in water; (2) micelles that form are small (based on SANS measurements) with lower aggregation numbers than for single-headed amphiphiles [27][28][29][31][32][33] as would be predicted based on geometrical considera- [30,31]; (4) cmc values are generally higher, and there is a decrease in the dependency of cmc versus chain length in a homologous series compared to single-headed amphiphiles, owing to an increase in hydrophilicity; (5) micellar size and shape is relatively insensitive to changes in temperature, concentration and added electrolyte [28,31]; (6) antibacterial activity increases with the number of headgroups for cationic amphiphiles due to multidentate interactions with an anionic bacterial cell surface [38]; and (7) amphiphiles with multiple amines are efficient phase-transfer agents for carrying sliver nanoparticles from an aqueous to an organic phase [37].…”