Adsorption and aggregation of 2-hydroxyl-propanediyl-α,ω-bis(dimethyldodecyl ammonium bromide) in aqueous solution: Effect of intermolecular hydrogen-bonding

Wormlike micelles formed by mixed cationic and anionic gemini surfactants in aqueous solution

“…Two cationic gemini surfactants, 2-hydroxyl-propanediyl-a,xbis(dimethyldodecylammonium bromide) and propanediyl-a,xbis(dimethyldodecylammonium bromide), referred to as 12-3(OH)-12 and 12-3-12, respectively, and an anionic gemini surfactant, O,O 0 -bis(sodium 2-dodecylcarboxylate)-p-benzenediol, referred to as C 12 /C 12 , were synthesized in our laboratory and reported elsewhere [29,34]. All the products were confirmed by 1 H NMR and elemental analysis as shown in Supporting materials.…”

“…In our previous work, the hydrogen-bonding interactions between 12-3(OH)-12 molecules have been verified to occur in both the disperse state of surfactant molecules in dilution and the aggregates in concentrated solution. In the dilute solution, dynamic surface tension and differential conductivity measurements gave out clear information for the formation of oligo-aggregate ions of 12-3(OH)-12 in solution prior to their adsorption and aggregation [29]. The phenomena were in sharp contrast with that of unsubstituted 12-3-12 and strongly suggested the hydrogen-bonding interactions between 12-3(OH)-12 molecules.…”

“…Even though the intermolecular hydrogen bonds have partly existed in the aggregates of 12-3(OH)-12 alone [29,39], its viscosity is only 0.8 Pa s at 80 mmol L À1 (Fig. 2).…”

“…On the basis of 12-3-12 and 12-4-12, the bis(quaternary ammonium halide) gemini surfactants with a hydroxyl-substituted spacer were synthesized and their properties were investigated in several groups [24][25][26][27][28]. In the very recent work [29], we found that in the system of 2-hydroxyl-propanediyl-a,x-bis(dimethyldodecylammonium bromide) that was referred to as 12-3(OH)-12 (Scheme 1), the hydrogen bonds can be formed between the hydroxyl-substituted spacers of the gemini molecules. Intermolecular hydrogen-bonding interaction is a kind of directive force.…”

“…As a supplementary and effective contribution besides a generally hydrophobic effect between the alkyl 0021-9797/$ -see front matter Ó 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.jcis.2010.12.065 tails, intermolecular hydrogen bonding has been verified to greatly promote the growth of 12-3(OH)-12 micelles [29]. In fact, in some other amphiphile systems, the significance of hydrogen-bonding interactions was also emphasized in the construction of supramolecular self-assemblies such as gel [30] or lamellar phases [31].…”